Full text of DOI:10.1046/j.1365-2044.2003.03415_23.x

Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
Correspondence
Research for research’s sake?
the efficiency of mask ventilation was two, which is after all what they use to
improved by administration of muscle calculate sample size. What is then
If Ruskin had been a scientist he would relaxants, would they have suggested tested statistically is the change in
surely have approved of the study that this may be a useful technique in VTe ⁄ VTi, which is different again.
undertaken by Goodwin et al. (Anaes- the group of patients that really interests
With such eminent persons putting
thesia 2003; 58: 60–3) to investigate the us, namely those who are difficult to their names to it, one of whom is on the
effects of neuromuscular blockade on mask ventilate?
editorial board of Anaesthesia, one can’t
mask ventilation of the lungs. Other
studies he may have enjoyed include:
This is another example of a study that help being rather perplexed by it all.
fails to address the question of genuine
N. Hutchinson
•
•
The effect of tourniquet application on interest because of the numbers or ethics
the efficiency of aspiration of blood involved. In common with many pub-
King’s College Hospital,
London SE5 9RS, UK
from a peripheral venous cannula.
The effect of increasing Fi
oxygen saturation in patients with clearly stating that their study was
lished studies, the authors allude to just
E-mail: nevil.hutchinson@which.net
O
on such a question in their final paragraph,
2
an oxygen saturation of 96% or above. unable, and was never designed, to A reply
In each case one is left wondering answer such a question, and that other, Thank you for an opportunity to reply
where lies the important clinical ques- larger studies might shed more light.
to Dr Hutchinson’s comments on our
tion to be answered.
Their suggestion that future studies study. Perhaps if Hutchinson had read
The question Goodwin et al. set out might actually focus on the group of our Introduction, he might have been
to try and answer is whether or not patients Ô… in whom mask ventilation is less perplexed as to our reasons for
there is any value in withholding neu- more likely to be difficultÕ teases the conducting the study. For his benefit,
romuscular blocking drugs following reader by rubbing in the fact that their we are grateful for the opportunity to
induction until an attempt is made to study was of no use in addressing this, repeat our reasons.
ventilate the lungs. The experiment the crux of the issue. Furthermore, it is
Our study arose from the observation
they designed was never going to unlikely that any Ethics Committee that trainees commonly give neuromus-
answer this question, because the reason would allow people to administer cular blocking drugs only after ÔtestingÕ
people do it is to detect the ÔcanÕt neuromuscular blocking agents to this the patient’s airway with a few ÔpuffsÕ
ventilate’ patients before it is too late. interesting group of patients.
Such patients are very rare, and certainly
not studied by the investigators.
from the reservoir bag via a facemask.
Although their study is of little We wished to know whether this
clinical interest, it does throw up a practice is justified or to be avoided.
So what were they up to? If they had few methodological points worth com- We did not know whether a previous
shown that administration of neuro- menting on. The setting of alpha and study [1] suggesting that full neuromus-
muscular blockade to ASA 1 or 2 beta errors at these levels seems un- cular blockade improves mask ventila-
patients with no known or obvious avoidable. We are told that the standard tion was correct, or whether the
airway problem reduced the efficiency deviation of the tidal volume had been alternative suggestions of other work
of mask ventilation, what useful clinical discovered previously to be 125 ml. It is [2], that neuromuscular blockade might
conclusion would they have drawn? not clear if this is expired (VTe) or worsen mask ventilation, were correct.
That we must stop doing it, or be inspired (VTi) tidal volume, or whether Hutchinson claims in his letter that he
careful if we do? If they had shown that they mean the difference between the would already have known the answer
All correspondence should be addressed to Professor M. Harmer, Editor of Anaesthesia, Department of Anaesthetics, University of
Wales College of Medicine, Heath Park, Cardiff CF14 4XN UK.
Letters (two copies) must be typewritten on one side of the paper only and double spaced with wide margins. In addition, please
include your letter as a Word for Windows or .rtf document on disk or alternatively submit as an e-mail attachment addressed to
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advice about references and other matters contained in the Notice to Contributors to Anaesthesia printed at the back of the January
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Correspondence presented in any other style or format may be the subject of considerable delay and may be returned to the author for
revision.
Ó 2003 Blackwell Publishing Ltd
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Anaesthesia, 2003, 58, pages 1023–1045
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.
(
but declines to state what this ÔobviousÕ question we addressed, a more con-
The clinical exposure of current
answer is). We were more ignorant than structive approach for him would be to trainees is now very different from that
Hutchinson and it is because of our design and conduct the follow-up study of existing consultants trained in the
ignorance (or in more correct scientific we suggested in the conclusion of our Ôpre-Calman ⁄ New DealÕ era. Gone are
parlance ÔequipoiseÕ) that we conducted paper.
the endless nights and weekends work-
ing on-call, during which exposure to
various paediatric emergencies could be
anticipated, particularly if duty respon-
sibilities involved simultaneous anaes-
thesia and ICU cover. Greater
centralisation of paediatric intensive
care to Lead Centres means that in
many acute trusts, the care of sick
children is now increasingly limited to
a relatively brief time interval prior to
the arrival of a retrieval team. The
opportunities for trainees to learn from
unplanned contact with sick children
have therefore diminished significantly.
Had these changes been accompanied
by modifications in training pro-
grammes to ensure that all anaesthesia
trainees gained clinical experience in a
Lead Centre paediatric intensive care
unit (PICU), then their adverse effects
might be minimised. Regrettably, how-
ever, it appears that the secondment of
trainees to PICUs appears to be at best
patchy, and in some regions such train-
ing is only facilitated for aspiring pae-
diatric anaesthetists or intensivists. A
further disincentive is that time spent in
paediatric intensive care may not even
be ÔrecognisedÕ for the mandatory per-
iod of training in critical care.
the study. Had we found that neuro-
J. J. Pandit
muscular blockade worsens mask venti-
lation, we would have concluded that
we must all be even more cautious
about neuromuscular blockade in pati-
ents who might be difficult to ventilate
by mask, and that the trainees’ practice
was justified. Had we found that neu-
romuscular blockade improves mask
ventilation, our conclusion would be
that trainees’ practice was not justified
because they were ÔtestingÕ the airway
when ventilation was at its most diffi-
cult. Thus (unlike Hutchinson) we
were entirely impartial in our approach
to the results of this study.
Hutchinson also criticises the way
we conducted our power calculation.
Much has been written about the
limitations of power calculations [3–6]
and an extensive response to his points
is beyond the scope of this letter. The
power of a study is the probability that
the study has to detect as statistically
significant a real difference of a given
magnitude [3]. If a study shows a
ÔnegativeÕ (i.e. non-significant) result,
then this might mean one or more of
the following. First, that there is a real
difference but the study had insufficient
power (i.e. was not large enough) to
detect this. Second, that the real differ-
ence is much smaller than was provi-
sionally predicted from the power
calculation. Third, that there is no real
difference. In most studies, we are not
interested in very small differences
John Radcliffe Hospital,
Oxford OX3 9DU, UK
E-mail: jaideep.pandit@physiol.ox.ac.uk
S. Yentis
Chelsea & Westminster Hospital,
London SW10 9NH, UK
E-mail: s.yentis@ic.ac.uk
References
1
2
Abrams JT, Horrow JC, Bennett JA,
Van Riper D, Storella RJ. Upper
airway closure. A primary source of
difficult ventilation with sufentanil
induction of anesthesia. Anesthesia and
Analgesia 1996; 83: 629–32.
Odeh M, Schnall R, Gavriely N,
Oliven A. Effect of upper airway mus-
cle contraction on supraglottic resist-
ance and stability. Respiration Physiology
1
993; 92: 139–50.
3
4
Yentis SM. The struggle for power in
anaesthetic studies. Anaesthesia 1996;
5
1: 413–14.
Baccheti P. Peer review of statistics in
medical research: the other problem.
British Medical Journal 2002; 324:
1
271–3.
5
6
Horrobin DF. Rationale for requiring
power calculations is needed. British
Medical Journal 2002; 325: 491–2.
Altman DG, Moher D, Schulz KF.
Reporting power calculations is
Given that the majority of future
district general hospital (DGH) consult-
ants for any region are likely to be
products of the School of Anaesthesia
based in the regional tertiary centre, any
failure to invest in their training carries
important future implications for the
local care of critically ill children. This
raises important questions about the
logic of training in anaesthesia.
important. British Medical Journal 2002;
3
25: 492.
(
however real or statistically significant Paediatric intensive care
they might be), so the power analysis is training
at best a rough guide to the study size
likely to detect only a relevant differ- Tomlinson summarises the problems Although training in paediatric anaes-
ence [5, 6]. This is what our study was surrounding the initial care of critically thesia teaches core skills in airway
designed to do. Power analysis is not, ill children in non-specialised hospitals management, assisted ventilation, phar-
nor intended to be, a Ôstatistical straight- (Tomlinson. Anaesthesia 2003; 58: 309). macology and fluid management, this
jacketÕ, which prevents all further intel- However, although the suggestions he does not necessarily confer confidence
ligent thought or necessary sensible makes to enhance the abilities of trusts in the management of potentially unsta-
modifications of study design. The to provide the required high standards ble critically ill children, particularly if
ultimate measure of ÔpowerÕ of the study of care are sensible, we believe that a training has been limited to the mini-
is the confidence interval of the actual lack of Ôjoined-up thinkingÕ in the mum of 3 months in predominantly
result obtained [4]. training of new consultant anaesthetists elective patients. Paradoxically, signifi-
We would suggest that if Hutchinson may continue to undermine attempts to cant amounts of time are still allocated
is truly interested in the scientific achieve these standards.
to training in elective and emergency
1
024
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Anaesthesia, 2003, 58, pages 1023–1045
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cardiac and neurosurgical procedures, Table 1 Most frequently used herbal medica- those herbal medicines with CNS activ-
tion.
yet most consultant anaesthetists work-
ing in non-specialist centres are very
unlikely to provide anaesthesia for car-
diopulmonary bypass surgery or for a
craniotomy. By contrast, however,
there is a high likelihood that these
same consultants will be involved with
the care of children either for elective
ity, such as valerian, Saint John’s wort
and kava, to reduce the likelihood of
% patients withdrawal reactions. Clearly, to ensure
% total
patients using using
potentially unnecessary cancellations of
surgery are avoided and safe anaesthesia
administered, the earlier that patients
taking herbal medicines can be identi-
fied the better. This is a challenge for all
departments of surgery and anaesthesia
as well as general practitioners.
Medication
(Sheffield)
(Slough)
Echinacea
Garlic
Ginseng
1.44
4.60
1.15
0.87
3.47
0.70
1.58
1.25
1.10
0.40
0.99
procedures or for emergencies. As the Gingko
Primrose
long-term outcome for critically ill
Saint John’s wort 1.15
children (if managed well) is consider-
ably better than for adult patients with
cardiovascular disease or neurological
trauma, why is there so little emphasis
on training in paediatric intensive care?
Perhaps it is time to re-examine the
priorities for training in anaesthesia. In
order to give the future generation the
best chance of survival, we must ensure
that consultants have the opportunity
first to acquire the necessary skills, as
well as developing strategies to maintain
them.
More studies extending the work of
Ang-lee et al. to include more common
herbs ingested in the UK are necessary to
arrive at a consensus about the need and
timescale for discontinuation of these
substances in the peri-operative period.
I would echo Dr McKenzie’s call for a
survey of current anaesthetic practice.
the prevalences reported in a larger
survey by Skinner & Rangasami in
Slough [2] and the Ôtop sixÕ most fre-
quently consumed substances are the
same, with three patients in our survey
taking kelp, ginger and aloe vera, and
lesser numbers taking valerian, prickly
ash and a plethora of other medications.
They are still considerably less than the
figures from the USA reported by Kaye
et al. from Texas [3] and Tsen et al. from
Harvard [4]. All of the medicines dis-
G. M. Lynch
Barnsley District General
Hospital,Barnsley, UK
E-mail: glynch@doctors.org.uk
B. Taylor
References
P. Donnison
cussed by Hodges & Lam, as well as some 1 Hodges PJ, Kam PC. The perioperative
Queen Alexandra Hospital,
Portsmouth PO6 3LY, UK
E-mail: bruce.taylor@porthosp.nhs.uk
M. Marsh
of those on Dr McKenzie’s list, appear. It
is likely, however, that considerable local
variation even within the UK exists.
I agree with Dr McKenzie’s opin-
ion that discontinuation of all herbal
remedies 2–3 weeks before surgery, as
implications of herbal medicines.
Anaesthesia 2002; 57: 889–99.
2 Skinner CM, Rangasami J. Periopera-
tive use of herbal medicines: a patient
survey. British Journal of Anaesthesia
2002; 89: 792–5.
Southampton General Hospital,
Southampton, UK
recommended in ASA publications, and 3 Kaye AD, Clarke RC, Sabar R et al.
Herbal medicines in the
United Kingdom
articles by Hodges & Kam and Leak
[1, 5], is probably unnecessary in some
cases, and might lead to unwanted
Herbal medicines: current trends in
anaesthesiology practice-a hospital
survey. Journal of Clinical Anaesthesia
2000; 12: 468–71.
I read with interest the recent corres- withdrawal effects. However, I feel that
pondence concerning the use of herbal continuation of, for example, valerian 4 Tsen LC, Segal S, Potheir M, Bader
medications in the pre-operative popu- through the peri-operative period, as
lation (McKenzie. Anaesthesia 2003; 58: he suggests, might prove unworkable in
597) and wish to add some information practice for anything other than day-
from a survey carried out at our hospital. case surgery.
Dr McKenzie makes the point that a Ang-lee et al. [6] in Chicago, con-
list of commonly sold licensed herbal centrating on the eight most commonly
AM. Alternative medicine use in
presurgical patients. Anesthesiology
2000; 93: 148–51.
5 Leak JA. Herbal medicines: what do we
need to know? American Society of
Anesthetists Newsletter 2000: 64.
substances obtained by him from the ingested substances in the USA, sugges- 6 Ang-Iee MK, Moss J, Yuan C-S.
manufacturers differs from the list of ted a means of tackling this problem
medications chosen by Hodges & Kam based on an extensive literature search of
in their Australian-based review [1]. A Medline, Cochrane and other databases
survey of 346 elective patients carried and utilising knowledge from reviews
out over 3 months using a standard concerning the pharmacokinetics of
Herbal medicines and perioperative
care. Journal of the American Medical
Association 2001; 286: 208–16.
questionnaire administered by nursing their active ingredients. They suggest Anorexia nervosa and the
staff in routine pre-operative assessment discontinuing ephedra and kava more refeeding syndrome
clinics for a variety of surgical specialties than 24 h before, gingko more than
at the Royal Hallamshire Hospital, Shef- 36 h before, Saint John’s wort 5 days or In their review of the anaesthetic
field, showed that the commonest sub- more before and garlic more than a implications of anorexia nervosa,
stances taken were as shown in Table 1. week before elective surgery. It would Drs Seller and Ravalia emphasise that
These figures agree reasonably well with seem reasonable to taper the doses of patients with this illness can suffer a
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Anaesthesia, 2003, 58, pages 1023–1045
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.
wide range of problems resulting in 3 Solomon SM, Kirby DF. The refeeding home but fell asleep at the wheel,
multisystem abnormalities (Seller
syndrome: a review. Journal of Parenteral sustaining fractures of both lower limbs
Ravalia. Anaesthesia 2003; 58: 437–
&
and Enteral Nutrition 1990; 14: 90–7.
in the ensuing accident.
4
3). We agree that: Ôin extreme cases, 4 Haglin L. Hypophosphataemia in
Whilst these are extreme examples,
Murray & Dodds’ paper does raise an
important question, not only about an
the patient may have to be fed nutrients
via a nasogastric tube or parenterally in
anorexia nervosa. Postgraduate Medical
Journal 2001; 77: 305–11.
order to sustain lifeÕ. Such treatments 5 Birmingham CL, Alothman AF, Gold- anaesthetist’s ability to work safely after
have important implications, which we
think warrant mention.
Provision of nutrition to a severely
malnourished patient (reported as less
ner EM. Anorexia nervosa: refeeding
and hypophosphataemia. International
Journal of Eating Disorders 1996;
20: 211–13.
sleep disturbance but possibly also about
his ⁄ her ability to drive safely.
J. Laurenson
Wansbeck General Hospital,
Ashington NE63 9JJ, UK
E-mail: john.laurenson@
northumbria-healthcare.nhs.uk
than 70% of ideal body weight [1]) carries 6 Rosen GH, Boullata JI, O’Rangers EA,
the risk of the Ôrefeeding syndromeÕ.
One definition is: Ôsevere electrolyte and
fluid shifts associated with metabolic
abnormalities in malnourished patients
undergoing refeeding, whether orally,
enterally or parenterallyÕ [2]. Provision of
substrate, nutrients and calories can pro-
voke rapid transcellular shifts of elec-
trolytes. The importance of serum
hypophosphataemia resulting from
refeeding has been stressed [3] and has
recently been reviewed by Haglin [4]. In
patients with anorexia nervosa, refeeding
syndrome implicating hypophosphatae-
mia has been associated with heart failure
Enow NB, Shin B. Intravenous phos-
phate repletion regimen for critically ill
patients with moderate hypophos-
phatemia. Critical Care Medicine 1995;
23: 1204–10.
Reference
Davies P. Anaesthesia News 2002; 176:
–2.
1
1
Sleep disruption and
performance
Teaching airway skills
I read with interest the paper: ÔThe effect
of sleep disruption on performance of The recent paper (Kiyama et al. Anaes-
anaesthetists – A pilot studyÕ (Murray & thesia 2003; 58: 571–4) highlights some
Dodds. Anaesthesia 2003; 58: 520–5). of the variations in anaesthetic practice
The authors suggest that poor perform- and approach to difficult airway man-
ance in a driving simulation test after a agement between two countries.
disturbed night may indicate an increased However, we do not believe that the
risk of a fatigue-related error occurring authors have arrived at the appropriate
during the conduct of anaesthesia. It conclusions.
[
1, 5] and neuropsychiatric events [1].
As anaesthetists may well be involved
with these patients for critical care as
well as in the peri-operative setting, it is
wise to be aware of such important
iatrogenic complications.
A scheme for treatment of ÔmoderateÕ
serum hypophosphataemia in critical
occurs to me that impaired vigilance
during the driving simulation test may that the absence of a formal module is
also indicate an impaired ability to drive indicative that airway training is a per-
First, it would be wrong to conclude
safely after a disturbed night on call.
Many anaesthetists after a very busy
night on call want nothing more than to
drive home. However, although it may is built.Õ [1]. Therefore, should we not
be unwelcome news, this may not be consider the entire anaesthetic time as a
the safest course of action. Dr Polly 7-year module? The question also re-
Davies has previously highlighted this mains as to whether or not a module
citing the extreme case of Gary Hart [1]. always gives better training. Mason goes
On 28 February 2001, Mr Hart spent on to point out that Ôdifficult techniques
ipheral activity. Mason stated that Ôairway
management is the scaffolding upon
which the whole practice of anaesthesia
)
1
care patients (between 0.32 mmol.l
)1
and 0.65 mmol.l ), with due regard for
refeeding syndrome, is described by
Rosen et al. [6].
E. Whyte
P. Jefferson
D. R. Ball
Dumfries and Galloway Royal
Infirmary,
5
h in telephone conversation during cannot be mastered during short work-
the night with a friend before driving shopsÕ. Instead: ÔExpertise in airway
his Land Rover and trailer along the management can only be acquired
M62. It appears that at 6:20 a.m., gradually, over a long period of clinical
Mr Hart lost control of the vehicle, experienceÕ. The areas of anaesthesia that
perhaps having fallen asleep. The Land we have found to benefit from modular
Rover came to rest on the main East training are relatively peripheral to our
Coast railway line where it led to a everyday anaesthetic practice, but give
train crash, which caused the death of regular, predictable training opportunit-
Dumfries DG1 4AP, UK
E-mail: s.jamieson@dgri.scot.nhs.uk
References
1
Kohn MR, Golden NH, Shenker IR.
Cardiac arrest and delirium: presenta-
tions of the refeeding syndrome in
severely malnourished adolescents with 10 people and injuries to many others. ies. Good examples would be intensive
anorexia nervosa. Journal of Adolescent
Health 1998; 22: 239–43.
Doctors are not immune from the care, cardiac and chronic pain. Clearly,
perils of fatigue whilst driving. I am this is the very opposite to airway man-
aware of one trainee doctor who was agement training.
2
Crook MA, Hally V, Panteli JV. The
importance of the refeeding syndrome. awake for most of his weekend on call.
All would agree that, ultimately,
Nutrition 2001; 17: 632–7. After his duty was finished, he drove airway training has to be experiential
1
026
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Correspondence
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and, owing to the nature of the difficult
airway, haphazard and opportunistic.
Therefore, should we not be offering
advanced airway training earlier to give
more time for trainees to come across
these opportunities and consolidate
their experience during their anaesthetic
training?
Royal London Hospital,
London E1 1BB, UK
progressive respiratory compromise was
admitted to the intensive care unit
(ICU) for ventilatory support. As she
was likely to have a prolonged intensive
care course, an early tracheostomy was
scheduled following informed consent
from next-of-kin. This was performed
as a PDT in the operating theatre for
logistical reasons. Bronchoscopy was
not available at the time of surgery.
Whilst in the ICU, sedation had been
maintained with midazolam and mor-
phine infusions. However, following
transfer to the operating theatre, this
was replaced by sevoflurane 1% in
oxygen, delivered via a circle circuit.
Non-depolarising neuromuscular block-
ade was achieved with atracurium.
In order to eliminate possible compli-
cations such as tracheal tube (TT) cuff
puncture, tube transection by needle, or
accidental extubation during the proce-
dure, we removed the patient’s TT and
replaced it with a laryngeal mask and
continued ventilation with sevoflurane
in oxygen via the latter. We attached the
sampling tubing from an Ohmeda 5330
Agent Monitor to the side port of a luer-
lock three-way-tap, and placed this in
series between a syringe and an intro-
ducer needle (Fig. 1). We then deter-
mined the location of the optimal entry
point on the patient’s skin and inserted
the needle through the skin. With the
three-way tap initially turned ÔonÕ to the
agent monitor for several minutes to
confirm a zero recording, the tap was
turned ÔoffÕ to the monitor and the needle
was advanced with the syringe aspirating
in the usual manner. Tracheal puncture
was suggested by entry of air into the
syringe. After entering the trachea, we
turned the three-way tap ÔonÕ to the agent
monitor, and paused to observe the
monitor. After one breath, the monitor
detected sevoflurane and displayed
appropriate values and commencement
of trend line (Fig. 2). We then removed
the syringe and tap from the needle,
advanced the guidewire through the
needle into the trachea and continued
uneventfully with Griggs’ dilating for-
ceps technique.
E-mail: hallhouse@btinternet.com
References
1
2
Mason RA. Education and training in
airway management. British Journal of
Anaesthesia 1998; 81: 305–7.
Finally, unlike the authors, we firmly
believe that the techniques taught should
be based on local practice and personal
experience. It is vital for all anaesthetists
to have an individualised difficult airway
plan, but based on established guidelines
such as the ASA Practice Guidelines for
the Difficult Airway [2]. However, even
the ASA Task Force failed to find strong
scientific data to justify recommending
one alternative airway or intubation
technique over any other [2]. Levitan
et al. [3] point out that as the genuinely
difficult airway is such a rare occurrence,
Ôassessment of alternative techniques in a
randomised manner would be techni-
cally impractical and would require such
a large number of patients that it is not
feasible.Õ Furthermore, we believe that in
any such study, the personal experience
we alluded to, and preference of the
operator would be a confounding factor
for any conclusions reached. Rather than
determining whether such a wide range
of techniques could be taught, we need
to ensure that all anaesthetists receive
adequate training in one technique for
each step of an airway algorithm, e.g.
gum elastic bougie or intubating stylet. It
is surely better to be taught to use one of
these well, rather than both badly. This
would be consistent with the aim of
rationalising the contents of the difficult
intubation trolley. Not only is it not
feasible to stock equipment for every
single technique, but worse, a cluttered
trolley is confusing and distracting in the
airway crisis.
Anon. Practice Guidelines for Man-
agement of the Difficult Airway. An
Updated Report by the American
Society of Anesthesiologists Task Force
on Management of the Difficult Air-
way. Anesthesiology 2003; 98: 1269–77.
Levitan RM, Kush S, Hollander JE.
Devices for difficult airway management
in academic emergency departments:
results of a national survey. Annals of
Emergency Medicine 1999; 33: 694–8.
3
Confirming tracheal
cannulation during
percutaneous tracheostomy
without endoscopic guidance
Percutaneous dilatational tracheostomy
(PDT) continues to replace conven-
tional surgical tracheostomy as the pro-
cedure of choice in adult intubated
intensive care unit patients, a group
which accounts for approximately two-
thirds of all tracheostomies performed
[
1]. Endoscopic guidance has been
advocated to enhance safety, with many
of the complications previously associ-
ated with percutaneous tracheal cannu-
lation being avoidable by the use of
direct bronchoscopic visualisation [2].
However, use of a bronchoscope may
impair ventilation [3], and endoscopy
may not always be possible or indeed
available for a variety of logistical rea-
sons. Recently, ventilation via the
laryngeal mask airway during PDT has
been shown to be effective and safe in
selected patients, with elimination of
the various difficulties associated with
tracheal tubes [4, 5]. We describe a
simple, inexpensive technique to con-
firm tracheal cannulation during PDT
without endoscopy, when performed in
the operating theatre in a patient ven-
tilated via a laryngeal mask using anaes-
thetic agent monitoring as an indicator
of successful tracheal cannulation.
To conclude, we wish to express our
concern at the move towards the false
promise of the Ôdifficult airway moduleÕ
rather than emphasising the fundamen-
tal duty of all practising anaesthetists to
train others or to improve our own
airway skills at every opportunity
throughout our anaesthetic careers.
Endoscopic guidance for PDT would
certainly be regarded by many as the
Ôgold standardÕ technique, but a broncho-
scope may not always be available for a
C. Taylor
M. Lim
A 35-year-old female with a diag-
nosis of Guillain–Barr e´ syndrome and
H. Drewery
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Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
nique is easy to perform and does not
prolong PDT insertion by any signifi-
cant duration. We suggest that this
method be employed in all situations
where PDT insertion occurs in the
operating theatre without endoscopic
guidance, where agent monitoring is
available.
Furthermore, we would envisage that
certain other anaesthetic monitors (such
as the Datex AS-3) that employ a similar
side-stream gas sampling method for
routine detection of oxygen and carbon
dioxide (in addition to anaesthetic
vapour) may be able to detect increased
levels of these two gases in a similar
manner, if used with our PDT insertion
technique. This, in turn, raises the
possibility that a portable side-stream
multigas analyser might be employed at
the bedside in the ICU to confirm
successful tracheal cannulation and
thereby reduce the numbers of critically
ill patients transported to theatre for
PDT insertion. We plan to investigate
this additional aspect shortly.
Figure 1 Model of three-way tap ⁄ agent-monitoring device to confirm tracheal cannulation (a test
lung is ventilated with 1% sevoflurane in 100% oxygen).
D. Honan
D. Malkan
E. Tierney
Wexford General Hospital,
Wexford, Ireland
E-mail: honan@iol.ie
References
1
2
Zeitouni A, Kost K. Tracheostomy.
A retrospective review of 281 cases.
Journal of Otolaryngolgy 1994; 23: 61–6.
Kost K. Percutaneous tracheostomy:
comparison of Ciaglia and Griggs
techniques. Critical Care 2000; 4:
1
43–6.
3
Deblieux P, Wadell C, McClarity Z,
de Boisblanc BP. Facilitation of per-
cutaneous dilational tracheostomy by
use of a perforated endotracheal tube
exchanger. Chest 1995; 108: 572–4.
Figure 2 Monitor showing agent detection after entry into ÔtracheaÕ as in Fig. 1.
variety of reasons. In such situations, it whose PDT is performed in the oper-
is useful to have an option other than ating theatre), this simple technique
just blind PDT with simple aspiration of may help to overcome the hazards 4 Dosemeci L, Yilmaz M, Gurpinar F,
air. By being able to detect anaesthetic associated with PDT insertion where
agent in the aspirated air, this technique endoscopy is not possible for logistical
not only confirms entry to the trachea, reasons, or for reasons of difficulty in
but also excludes accidental entry to that ventilating the patient’s lungs with the
other source of gas in the neck, the bronchoscope in situ. Once the trachea
Ramazanoglu A. The use of the laryn-
geal mask airway as an alternative to the
endotracheal tube during percutaneous
dilatational tracheostomy. Intensive Care
Medicine 2002; 28: 63–7.
oesophagus.
has been cannulated by the needle, 5 Grundling M, Kuhn SO, Riedel T,
Whilst limited initially to patients anaesthetic agent may be detected via
who can be ventilated with a detectable the three-way-tap after a very short
anaesthetic agent (which, in practice, time (15–20 s), giving early confirma-
usually comprises that subset of patients tion of correct placement. The tech-
Feyerhard F, Wendt M. Application of
the laryngeal mask for elective percu-
taneous dilatation tracheotomy. Anaes-
thesiologie et Reanimation 1998; 23: 32–6.
1
028
Ó 2003 Blackwell Publishing Ltd

Anaesthesia, 2003, 58, pages 1023–1045
Correspondence
....................................................................................................................................................................................................................
.
Anaesthesia in an adolescent
with Ohtahara syndrome
planned necessity to reduce cerebral after surgery is interesting; this was
excitation on emergence from anaes- possibly a manifestation of the anticon-
thesia. Recovery from general anaes- vulsant effects of thiopental. Finally, as
We would like to present the anaes- thesia was uncomplicated and the with all patients with recurrent seizure
thetic management of an adolescent patient’s trachea was extubated when activity, the risk of neuroexcitation
with Ohtahara syndrome and acute he was fully awake to avoid the risks during an awake tracheal extubation
testicular torsion. Ohtahara syndrome of regurgitation and aspiration. The had to be balanced against the risk of
is an early-onset, epileptic encephalo- patient was admitted to a paediatric aspiration of gastric contents.
pathy, first reported in 1978 [1]. It high-dependency unit (HDU) for 24 h
H. Boyce
manifests itself by early infantile onset, postoperatively. This immediate post-
R. Satya-Krishna
intractable seizures, suppression bursts operative period progressed smoothly
Northampton General Hospital,
in awake or sleeping state electro- with no seizures or complications.
Northampton NN1 5BD, UK
encephalography (EEG), severe psycho-
motor retardation and poor prognosis.
The patient was subsequently
re-admitted to HDU following gener-
E-mail: morpheusinuk@ntlworld.com
A 15-year-old male presented to our alised tonic clonic convulsions on the
hospital with acute testicular torsion paediatric ward on the second post-
requiring orchidectomy. He was diag- operative day. A partially successful
nosed with Ohtahara syndrome after attempt was made to treat the convul-
generalised convulsions on day 1 after sions with lorazepam as per a previously
full-term normal delivery. Previously, agreed regimen. The patient was
attempts had been made to control his discharged the following day at his
fits using phenobarbitone, nitrazepam, father’s request as he was exhibiting
sodium valproate and thiopental, all of his normal pattern of seizure activity.
References
1
2
Vigevano F. Ohtahara syndrome. 1998
http://www.epilepsy.org/ctf/
ohtahara_syndrome.html.
Fragen RJ, Avram MJ. Barbiturates.
In: Miller RD, ed. Anesthesia, 4th edn.
New York: Churchill Livingstone
1
994, 236.
which were unsuccessful. On this
To the best of our knowledge, this is
admission, he was on long-term therapy the first case report of a general anaes- The nasal intubation aid (NIA)
with lamotrigine, vigabatrin, pyridox- thetic in a patient with Ohtahara syn-
ine, lioresal and diazepam. A potential drome. This syndrome presented We read with interest the review
full stomach, a recurrent coryzal illness difficulties with the anaesthetic through article: ÔNasotracheal intubation for
and fixed flexion deformity of the lower management of young age, mental head and neck surgeryÕ (Hall & Shutt.
limbs, as well as severe mental retarda- retardation, history of frequent and Anaesthesia 2003; 58: 249–56) and want
tion further complicated the case.
intractable seizures and the potential to remind you of the presentation of
Intravenous access was aided by top- effects of polypharmacy. A few inter- our Ônasal intubation aidÕ (NIA) – to our
ical anaesthesia achieved with ametop esting issues presented themselves mind a tool that should not fall into
cream and monitoring was applied as during the management of this case. oblivion.
per AAGBI guidelines. Pre-oxygen- Pre-operatively, a literature search of
As the authors pointed out, naso-
ation was difficult to perform, as the standard textbooks and an online search tracheal intubation can lead to certain
patient was uncooperative. General (Pubmed) using the keywords ÔOhtahara complications. About 20 years ago, we
anaesthesia was induced with a rapid syndromeÕ and Ôanaesthesia*Õ failed to published an article [1] describing a
sequence induction using thiopental provide any information about the device protecting the nasal passage.
)
1
(
7 mg.kg )
and
1 mg.kg ), and cricoid pressure was syndrome. A reference was located on a used in our department with respect-
succinylcholine anaesthetic management of Ohtahara For many years, this tool has been
)1
(
applied immediately after induction of Google search [1]. The anaesthetic plan able success. We examined this device
anaesthesia. The patient’s trachea was in- was finalised after discussion with the in a clinical trial that proved a signi-
tubated easily with a 7.5-mm ID cuffed consultant anaesthetist on call.
ficantly reduced incidence of false
During induction of anaesthesia, an passage, mucosal damage, erosion and
oral tracheal tube. Intra-operative opi-
)
1
)1
oid analgesia (fentanyl 1 lg.kg ) was additional dose of thiopental 2 mg.kg
supplemented with paracetamol and was required to produce adequate hyp-
bleeding.
Our NIA consists of a curved, flex-
diclofenac suppositories and local anaes- nosis. Minor neuroexcitatory side- ible and distal closed catheter of 25 cm
thetic to the wound site. Anaesthesia effects of thiopental during induction length and 0.4 cm diameter. At one end
was maintained with a mixture of [2] (nystagmus and fleeting twitches) is cellophane wrapping open on the
nitrous oxide, oxygen and sevoflurane. were observed. The lack of formal EEG other side to pick up the distal end of a
)
1
Atracurium (0.5 mg.kg ) was used during anaesthesia meant that we were cuffed tube. The wrapping helps to
with neuromuscular monitoring to aid unaware of any seizure activity during protect the cuff from damage and
intermittent positive pressure ventila- the general anaesthetic. There was a prevents false passage, carriage of nasal
tion in order to maintain normal oxy- normal response to neuromuscular flora into the trachea and abrasion of the
genation and end-tidal carbon dioxide blocking and opiate drugs. The lack of nasal mucosa, provided the chosen tube
levels. A pain-free recovery was a ÔnormalÕ seizure activity in the first 24 h is of an appropriate size (Fig. 3).
Ó 2003 Blackwell Publishing Ltd
1029

Correspondence
Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
Reference
syringe pump and manually to program
the correct syringe size.
Although in this case there was no
harm caused to the patient, we feel the
potential risks from this equipment
1
Doehn M, H o¨ rmann K, Bause HW,
Rockemann M. Introduction of an
insertion aid for nasal intubation.
An a¨ sthesie, Intensivtherapie und Notfall-
medizin 1985; 20: 289–91. [In German] failure are great. The Graseby 3000
range of syringe pumps are used in a
variety of situations, for example intra-
A potential hazard with Graseby
000 syringe pumps
venous opiate and intravenous insulin
infusions, where effectively doubling
the infusion rate, as in this case, could
be life threatening. In addition, if the
syringe pump was to recognise incor-
rectly a 50 ⁄ 60-ml syringe size as a 5-ml
syringe size, which would be the worst-
case scenario, then the actual infusion
rate could be as high as five times the set
rate because the linear scale on a 5-ml
BD Plastipak syringe is five times longer
than a 60-ml BD Plastipak syringe.
3
The Graseby 3000 series of syringe
pumps is designed to accept different
sizes of syringe, ranging from 5 ml to
5
0 ⁄ 60 ml. In addition, they can be
programmed to recognise syringe sizes
of varying brands, although this is usu-
ally a factory-preset function. The ability
of the pump to recognise the syringe size
is integral to the accurate rate of delivery
from the syringe. It is achieved by a lever
that springs down onto the side of the
syringe and detects its diameter. In the
We would therefore like to emphasise
the importance of checking for correct
syringe size recognition by the Graseby
Figure 3 The ÔNasal Intubation AidÕ in situ.
By gently pulling and pushing (see arrows), the
tube is guided through the nasal passage.
3
100, 3150, 3200 and 3300 PCA mod-
3
000 syringe pumps prior to use.
els, the detected syringe size is displayed
as a light-emitting diode (LED) on the
control panel. In the 3400 and 3500
models, the detected syringe size is
displayed in text on the display screen.
We would like to report an incident
D. A. C. Wilkinson
N. Mc C. Schofield
We found that trauma caused by nasal
intubation was significantly reduced –
an important gain. This was shown by
lower rates of aching near the nasal root,
blood-tinged mucous and impaired nasal
breathing. Rare situations such as cuff
damage, switching to the contralateral
nostril, mucosal dissection or impossible
nasal intubation did not occur when
using the NIA. Both conventional and
the intubation with NIA lead to typical
complications such as erosions and
bleeding. However, we found a signifi-
cantly reduced risk of these complica-
tions in the NIA. For example, the
frequency of bleeding was decreased
from 58% in the conventional intubated
tracheas to 11% when intubated with
the NIA. We assume that, in addition,
our tool is useful when there is abnormal
coagulation because of its trauma-redu-
cing qualities. Above all, it is safe, ready
and easy to use and of negligible cost in
comparison with its benefit.
The John Radcliffe,
Oxford OX3 9DU, UK
that occurred during an elective laparo- A reply
tomy in a 68-year-old patient under Thank you for the opportunity to reply
general anaesthesia with a thoracic epi- to Drs Wilkinson and Schofield’s letter.
dural infusion, sited at T10 ⁄ 11. The Graseby Medical Ltd agrees that check-
epidural infusion was bupivacaine 0.25% ing the syringe information displayed by
in a 60-ml BD Plastipak syringe, running the pump with that being used is
)1
at 6 ml.h from a Graseby 3100 with important in ensuring the safe delivery
factory settings to recognise BD Plastipak of the infusion. The very first warning
syringes. After about 90 min, it was in the current Instruction Manual for
noted that the Graseby syringe pump the Graseby 3100 states ÔWARNING:
had already delivered 20 ml, which was To avoid over- or under-infusion,
more than double the expected amount always verify that the brand and size of
of 9 ml. Immediately it was noted that the loaded syringe are the same as the
the Ô20-mlÕ LED was displayed rather brand and size displayed on the screen
than the Ô50 ⁄ 60-mlÕ LED, and the pump before starting the infusion. Failure to
was stopped and exchanged for another. do so may result in an inaccurate
The patient came to no harm.
delivery of medication, resulting in
The problem was caused by failure of patient injury or death.Õ This warning
the spring lever mechanism, causing the is repeated in section 2.3 of the manual,
pump to default to the 20-ml syringe where syringe loading is described. This
size selection, regardless of the position warning appears in the same format in
of the lever. The resulting infusion rate all the Instruction Manuals of Graseby
was therefore appropriate for a 20-ml syringe pumps. It is also emphasised in
BD Plastipak syringe at 6 ml.h , all training materials for these pumps.
which, in terms of linear scale, equates The authors correctly note that there
to about 13 ml.h from a 60-ml BD is no facility manually to override the
Plastipak syringe. It should be noted pump and enter the correct syringe size
that there is no facility to override the in the case of a pump not measuring the
We conclude by hoping that this
useful tool will no longer remain over-
looked and unmentioned.
)1
M. Doehn
E. Monaca
)1
Kliniken der Stadt Koln,
5
1109 Koln, Germany
E-mail: enrico@monaca.de
1
030
Ó 2003 Blackwell Publishing Ltd

Anaesthesia, 2003, 58, pages 1023–1045
Correspondence
....................................................................................................................................................................................................................
.
syringe barrel appropriately. Graseby Low acceptance by adult patients and 4 Lake APJ. Sevoflurane vs. isoflurane: a
clinical comparison in day surgery.
Medical would not support this facility parents at recruitment to the study (23%
as it actually increases the risk of further and 25%, respectively), together with
problems because the user would not problems related to mask induction, 5 Cholwill JM, Wright W, Hobbs GJ,
Anaesthesia 2002; 57: 621–2.
know the reason for the fault and the might have led to bias, but with the
implications of manually overriding the large numbers overall and PONV not
pump. Current Graseby syringe pumps, the primary outcome measure, this is
e.g. Omnifuse, would not exhibit this acceptable.
Curran J. Comparison of ondansetron
and cyclizine for prevention of nausea
and vomiting after day-case gynaeco-
logical laparoscopy. British Journal of
Anaesthesia 1999; 83: 611–14.
fault as we have upgraded the design of
The results of the study should come
the size sensing system such that the as no surprise, and a good demonstra- 6 Grimsehl K, Whiteside JB, Mackenzie
software is more intelligent and would tion that propofol is effective even
detect the mismatch between the size when the sole anti-emetic, with only
registered and the size requested, and 14–18.4% of adults and 6% of paediatric
the pump asks the user to confirm the patients experiencing PONV, which
N. Comparison of cyclizine and
ondansetron for prevention of nausea
and vomiting in laparoscopic day-case
gynaecological surgery. Anaesthesia
2002; 57: 61–5.
size and brand of the syringe.
supports previous work [2, 3]. Omission
Graseby Medical regrets the incident of propofol led to a significant increase
and apologises for the inconvenience in PONV but no resultant overnight in-
A reply
caused.
hospital stays, and the conclusion from
the study has to be that propofol should
be included in every day-surgery gen-
eral anaesthetic technique for both its
cost and clinical effectiveness.
We are not proponents of routine
sevoflurane use for day-surgery as
evinced by current evidence-based
practice [4] but consider that future
research might usefully be directed to
examine possible benefits arising from
inhalation induction and maintenance
of anaesthesia at low flow when com-
bined with an alternative cost-effective
anti-emetic such as cyclizine [5, 6].
We thank Drs Lake and Khater for their
interest in, and support of, our study.
We would like to respond to the issues
they have raised regarding handling of
risk factors for postoperative nausea and
vomiting (PONV) in our study.
There are many factors that affect the
incidence of PONV. The aim of the
CESA randomised controlled trial was
to maximise generalisability and thus to
inform practical decision making for
clinicians and funders. This requires
studying sufficient numbers of patients
using a design reflecting real-life anaes-
thesia practice. The large sample size
and meticulous randomisation, further
stratified by sex and by surgical speci-
alty, resulted in recognised confounding
factors being evenly distributed
between groups [1].
M. Stewart
Marketing Manager,
Graseby Medical Ltd,
Watford WD24 4LG, UK
E-mail: Malcolm.stewart@
graseby.co.uk
Clinical and economic choices
in anaesthesia for day surgery
Publications designed to enable practi-
tioners to make appropriate choices
regarding anaesthesia for day surgery
are welcome, and the recent article
A. P. J. Lake
(
2
Elliott et al. Anaesthesia 2003; 58: 412–
1) is a major contribution, which we
M. Khater
Ysbyty Glan Clwyd,
Rhyl LL18 5UJ, UK
E-mail: sue.pain@cd-tr.wales.nhs.uk
found interesting, though somewhat
difficult to fathom despite one of us
(
A.P.J.L.) having a qualification in
health economics. The importance of
avoiding postoperative nausea and vom-
iting (PONV) in association with day 1 Everett LL, Kallar SK. Postoperative
Our recruitment rates were 77% of
adults and 75% of parents approached,
which is a relatively high acceptance
and is unlikely to have led to serious
bias in the results. Two hundred and
References
surgery, both in terms of delayed
discharge and also adverse events at
home, is well recognised by all practi-
complications. In: White PF, ed.
Ambulatory, Anesthesia and Surgery.
London: WR Saunders, 1997, 487–95. twenty-six adults and 59 parents refused
tioners, and simple, cost-effective man- 2 Tramer M, Moore A, McQuay H.
to enter the study because of the risk
that they might be randomised to a
mask induction, suggesting that the
prospect of a sevoflurane induction
may be unacceptable to many patients.
Our study found low overall levels of
PONV, despite the lack of anti-emetics,
and little differences in overall costs to
the NHS between the anaesthetic reg-
imens investigated. This suggests that,
where there are no other clinical con-
siderations, patients’ preferences should
be considered when selecting an anaes-
thetic technique for day surgery.
oeuvres to achieve this must be
built into the anaesthetic technique
Propofol anaesthesia and postoperative
nausea and vomiting: quantitative
systematic review of randomised
controlled studies. British Journal of
Anaesthesia 1997; 78: 247–55.
and should include
a prophylactic
anti-emetic for high-risk cases [1]. The
objective of the study was to assess
relative value for money in terms of 3 Kim SI, Han TH, Kil HY, Lee JS,
both the NHS and the patient, and not
an examination of PONV as such. This
would explain the absence of risk factors
for PONV in the baseline data, and the
randomisation between anaesthetic
regimens stratified by hospital and sex
only allowing a range of techniques.
Kim SC. Prevention of postoperative
nausea and vomiting by continuous
infusion of subhypnotic propofol in
female patients receiving intravenous
patient-controlled analgesia. British
Journal of Anaesthesia 2000; 85:
898–900.
Ó 2003 Blackwell Publishing Ltd
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Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
R. Elliott
50 Hz stimulation showed 10 weak suggestive of a heterozygous phenotype,
twitches. Neostigmine 2.5 mg and which can lead to a normal or slightly
glycopyrronium 0.5 mg were adminis- prolonged response to the administra-
tered intravenously. TOF stimulation tion of succinylcholine or mivacurium.
revealed four twitches with fade in The pronounced decline in cholinest-
amplitude, and as the patient was now erase activity cannot be accounted for
able to breathe spontaneously and nod by a dilutional effect, suggesting an
in acknowledgement to our voices, her acquired cause for the prolonged neuro-
University of Manchester,
Manchester M13 9PL, UK
E-mail: rachel.elliott@man.ac.uk
Reference
1
Elliott RA, Payne K, Moore JK
et al. Which anaesthetic agents are
cost effective in day surgery?
Literature review, national survey of
practice and randomised controlled
trial. Health Technology Assessment
trachea was extubated.
muscular paralysis in addition to the
In recovery, it became apparent that, genetic predisposition. However, the
despite maintaining peripheral oxygen cause for the postoperative fall in
saturations of greater than 97%, sponta- dibucaine number is unclear.
neous ventilation was inadequate.
The half-life of plasma cholinesterase
2
002; 6: 1–264.
Therefore, her trachea was re-intubated is between 45 h and 16 days, depending
following propofol (50 mg) and she was on the method used to measure it [2].
re-established on positive pressure ven- Repeated use of drugs that utilise
Prolonged paralysis following
sequential mivacurium
administration
tilation with inhalational sedation.
cholinesterases for metabolism within
Because of the possibility of choli- this time frame should be avoided,
nesterase deficiency, one unit of fresh especially where there is evidence of
We wish to describe a case of acquired frozen plasma was administered intra- impaired hepatic synthesis. The admin-
cholinesterase deficiency causing pro- venously. Nearly 3 h after the end of istration of fresh frozen plasma or a
longed paralysis following sequential surgery, the patient was able to obey purified human form of cholinesterase
anaesthetics using mivacurium 2 days commands, lift her head off the pillow can be used to hasten recovery of
apart. The patient, who was not known and had bilateral grip strength in her neuromuscular function but the benefit
to have the heterozygous atypical hands of 3 ⁄ 5. Her trachea was therefore should be weighed against the risks of
phenotype, had previously undergone extubated, without event. Postoperative exposure to blood products [2].
an oesophagogastrectomy in 1988. She analysis of pre- and postoperative blood
was cachexic and weighed 50 kg. Her samples are shown in Table 2.
Mivacurium is a short-acting agent
that does not normally require reversal.
The patient’s condition gradually It is not uncommon for anaesthetists to
past medical history was otherwise
unremarkable. Routine pre-operative deteriorated over the next few days, use neostigmine to reverse mivacurium-
investigations were normal. Subsequent and she died peacefully 5 days after the induced blockade. The manufacturer’s
analysis of the pre-operative blood second procedure. A serum sample data sheet for Mivacron (GlaxoSmith-
sample revealed evidence of mild liver referred to the Cholinesterase Investi- Kline) does not, however, give specific
dysfunction (elevated alkaline phospha- gation Unit in Leeds confirmed this advice for the use of neostigmine to
tase and aspartate transaminase) and a patient’s phenotype to be heterozygous assist reversal of neuromuscular block-
low serum albumin concentration.
For the first procedure of upper variants (i.e. UA).
airway panendoscopy, general anaesthe-
Mivacurium is metabolised predom- esteratic portion of the cholinesterase
for the usual and atypical cholinesterase ade [3]. Neostigmine methylsulphate
transfers a carbamate group on to the
sia was induced with fentanyl (75 lg), inantly by enzymatic hydrolysis by enzyme and is a potent reversible
propofol (120 mg) and mivacurium plasma cholinesterases [1]. The activity inhibitor of plasma cholinesterase. Neo-
(
12 mg), and maintained with oxygen, of this enzyme can be reduced by stigmine may therefore cause a para-
air and isoflurane. The procedure lasted physiological, inherited or acquired doxical early but incomplete return of
0 min and revealed a large fungating causes (including malignancy, malnutri- neuromuscular function.
pharyngeal tumour. Spontaneous respir- tion and hepatic impairment, all of
Edrophonium is a less potent inhib-
4
ation was re-established prior to extu- which were present in this patient [2]). itor of plasma cholinesterase, reversibly
bation of the trachea and an uneventful The pre-operative results in this case are inhibiting acetylcholinesterase by bind-
recovery followed. Reversal of neuro-
muscular paralysis was not required.
ing to the anionic site and may be a more
logical agent to antagonise the action of
Two days later, a feeding gastrostomy Table 2 Patient’s cholinesterase results (nor- mivacurium. Antagonism with neostig-
mal range).
was required to be placed. Anaesthesia
was conducted in a similar manner. On
completion of the surgery after 45 min,
there was no evidence of a return of
mine in this case may have delayed the
return of neuromuscular function
Post-op. despite the presence of four twitches in
response to TOF stimulation.
Pre-op.
spontaneous respiration. Supramaximal Serum cholinesterase
61
61
13
17
In summary, we present a case of
prolonged neuromuscular paralysis due
to mivacurium of multifactorial origin.
Despite evidence of a pharmacogenetic
54–125 U.ml)
1
)
(
train-of-four (TOF) stimulation at 2 Hz
of the ulnar nerve revealed no twitch.
Post-tetanic twitch count in response to
Dibucaine number
76–82% inhibition)
(
1
032
Ó 2003 Blackwell Publishing Ltd

Anaesthesia, 2003, 58, pages 1023–1045
Correspondence
....................................................................................................................................................................................................................
.
predisposition to abnormal metabolism,
the acquired factors of malnutrition,
liver dysfunction and malignancy are
likely to have been more significant in
this case, particularly as the two proce-
dures were so close together.
Finally, Intavent (the company that
manufacture the Laryngeal Mask Air-
way) oppose any alteration in their
equipment and would not be liable if
any problem had occurred due to this
mistake. We have suggested that our
Sterile Services Department stop this
practice of adding tape to laryngeal
mask airways.
M. Williams
R. M. Young
Q. J. W. Milner
Queen Alexandra Hospital,
Portsmouth PO6 3LY, UK
E-mail: qjwm@globalnet.co.uk
C. Smith
R. Clark
Manchester Royal Infirmary
Manchester, UK
References
1
2
3
Basta SJ. Clinical pharmacology of
mivacurium chloride: a review. Journal
of Clinical Anesthesia 1992; 4: 153–63.
Davic L, Britten JJ, Morgan M. Cho-
linesterase – its significance in clinical
practice. Anaesthesia 1997; 52: 244–60.
Savarese JJ, Caldwell JE, Lien CA,
Miller RD. Pharmacology of muscle
relaxants and their antagonists. In:
Miller RD, ed. Anaesthesia, 5th edn.
Reference
1 The Association of Great Britain
and Ireland. Checklist for Anaesthetic
Apparatus. London: AAGBI, 1997.
Figure 4
Digital block improves pulse
oximetry signal in
vasoconstricted patients
same problem were identified before
Edinburgh: Churchill Livingston, 2000, anyone had tried to use them. The Pulse oximetry is a cornerstone of
4
55–72.
source of the problem was discovered to minimum peri-operative anaesthetic
be a new member of staff in the Sterile monitoring and has undoubtedly
Services Department who had not real- improved patient safety since its intro-
ised the clinical importance of the duction. It does, however, have a
Airway equipment failure
due to a new staff member
in Sterile Services
positioning of the tape.
number of well-recognised limitations,
This incident re-emphasises the including failure to detect a reading in
importance of checking all ancillary peripherally vasoconstricted patients.
All new laryngeal mask airways in our equipment, as described in the Associ- This occurs if the monitor is unable to
hospital are labelled with a strip of ation of Anaesthetists Equipment detect pulsatile blood flow, which is
coloured tape to identify the theatre Checklist [1]. Laryngeal masks should necessary to distinguish arterial blood
complex that it is from (it is a large be included in this. In addition, it flow from tissue, bone, capillary and
teaching hospital with eight separate demonstrates that all staff working with venous signals. Peripheral vasoconstric-
operating theatre sites). This coloured equipment need to have some know- tion often occurs in patients who are
tape is positioned at the proximal end of ledge of its clinical function to prevent critically unwell and in whom reliable
the laryngeal mask, just below the mistakes like this happening. There is pulse oximetry is highly desirable. The
standard 15-mm connector (Fig. 4, currently no obligation for Sterile Ser- use of probes placed on the ear, buccal
left). During a routine pre-operative vices staff to spend any of their training mucosa, or the nose, instead of a digit,
equipment check, a faulty laryngeal in theatre. In our trust, Sterile Services can sometimes overcome this problem.
mask was identified (Fig. 4, right). staff do spend a day observing in theatre.
In situations where these options fail,
The problematic laryngeal mask had its However, this is limited to surgery and I would propose performing a suitably
identification tape placed directly on the they do not get any specific training in placed digital block using plain 2%
1
5-mm connector rather than in the the clinical uses of anaesthetic equip- lidocaine. The vasodilatation this causes
correct position just below the 15-mm ment. There are currently no national will produce a reliable pulse oximetry
connector (Fig. 4, left). The small training programmes for Sterile Services signal within 10 min, in my experience.
increase in diameter caused by the tape Department staff but one is being Digital nerve blocks are extremely safe,
then made it impossible to connect the developed and there will be a pro- the major potential complications being
laryngeal mask to a standard catheter gramme set up by the end of this year infection or the inadvertent use of a
mount, rendering it useless. Fortu- that should, we hope, address some of solution containing a vasoconstrictor,
nately, this was discovered before the these training issues (Susan Meredith, although the danger of this when using
patient was anaesthetised. On investiga- Director of Education, The Institute of lidocaine has recently been questioned
tion of the other anaesthetic rooms, five Sterile Services Management, personal [1]. Potential benefits of having a pulse
more laryngeal mask airways with the communication).
oximetry reading need to be weighed
Ó 2003 Blackwell Publishing Ltd
1033

Correspondence
Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
against resorting to a more invasive the anaesthetic course, boluses of eph- diagnosed. The affected area turned
strategy.
edrine (total 27 mg) were given in order gangrenous. Four days later, the patient
to maintain stable haemodynamics. underwent amputation of his left thumb
Postoperatively, the patient became and index finger.
P. D. Erasmus
Royal Perth Hospital,
Perth, Australia
hypotensive in the neurosurgical inten-
The most common complication of
sive care unit. High infusion rates of radial artery catheterisation is thrombo-
dopamine and norepinephrine were sis. This, however, very rarely leads to
needed to maintain an adequate blood ischaemic injury of the hand. The
pressure. There were episodes of fast classic study on the safety of radial
atrial fibrillation. An echocardiogram of artery cannulation by Slogoff et al. [1]
the heart showed no intracardiac throm- prospectively examined the radial artery
bus. The left radial artery catheter was flow by Doppler after decannulation in
removed on the fifth postoperative day. 1699 patients. They found partial or
On the seventh postoperative day, her complete radial artery occlusion after
left index finger was noticed to have decannulation in more than 25% of the
turned purple in colour. A diagnosis of patients, but no ischaemic damage or
radial artery thrombosis was made. A disability of the hand occurred in any
conservative management approach was patient. Only 411 (24%) patients had
adopted as, owing to her intracranial the modified Allen’s test performed
pathology, anticoagulation was contra- before cannulation. Abnormal results
indicated and surgery deemed inappro- (greater than 15 s for the return of
priate. Over the following few weeks, perfusion) were found in 16 patients.
the distal phalanx of her left index finger None of the 16 had abnormal flow or
developed into a dry gangrene (Fig. 5), ischaemia on subsequent examination.
E-mail: perasmus@doctors.org.uk
Reference
1
Wilhelmi BJ, Blackwell SJ, Miller JH
et al. Do not use epinephrine in digital
blocks: myth or truth? Plastic and
Reconstruction Surgery 2001; 107: 393–7.
Gangrene of digits associated
with radial artery cannulation
Arterial cannulation is the most com-
mon method of invasive blood pressure
monitoring in the operating theatre and
the intensive care unit. It allows con-
tinuous direct blood pressure measure-
ment and blood sampling. The radial
artery is often chosen, as it is superficial,
allowing easy palpation with high suc-
cessful cannulation rates, is conveniently
accessible by the anaesthetist in most
situations and is not an end artery.
Several studies have demonstrated that
vascular insufficiency from radial artery
catheterisation is extremely rare, at least
in patients without peripheral vascular
disease. The risk of vascular insuffi-
ciency is, however, increased in patients
with peripheral vascular disease and in
those who have a haemodynamically
unstable postoperative course. Staff
need to be alert to such a complication.
We present two cases of digital gan-
grene necessitating amputation after the
radial artery had been cannulated in the
operating theatre. Both patients had
peripheral vascular disease and a very
unstable postoperative course requiring
high inotropic support.
necessitating amputation.
They concluded that there was a high
An 84-year-old man with a history of risk (more than 25%) of partial or
ischaemic heart disease requiring several complete occlusion of the radial artery
previous coronary angioplasty interven- after cannulation but there were no
tions was admitted with an intracerebral important clinical consequences of
haemorrhage. An emergent craniecto- thrombosis, and that the Allen’s test
my for clot evacuation was scheduled. was not useful in predicting ischaemic
In the operating theatre, an intra-arterial damage or abnormal flow after radial
catheter was inserted into his left radial artery cannulation.
artery. The surgery and anaesthesia
There have been reports on ischae-
went smoothly and lasted around 1 h. mic damage to the hand following radial
Postoperatively, in the intensive care artery cannulation. Such ischaemic
unit, he developed fast atrial fibrillation damage developed a few days after the
and septic shock, requiring a norepi- cannulation and all patients had exhib-
nephrine infusion. On the ninth post- ited the risk factors of postoperative
operative day, the intra-arterial catheter hypotension and peripheral vascular
was removed. Three days later, the disease. There have been sporadic
patient’s left thumb and index finger reports on the ischaemic complication
were noticed to have turned purple in of arterial cannulation. Arthurs [2] des-
colour, with reduced capillary return. cribed digital ischaemia on the seventh
Acute ischaemia affecting the thenar postoperative day in a 78-year-old man
eminence, thumb and index finger was with bilateral femoral aneurysms sched-
uled for a femoral artery bypass graft.
An 80-year-old woman with a past
medical history of atrial fibrillation and
evidence of inferior myocardial infarc-
tion on ECG was admitted after collap-
sing at home. A CT scan and angiogram
of her brain revealed a large subarach-
noid haemorrhage from a ruptured
cerebral aneurysm. An emergent cranio-
tomy for clot evacuation was scheduled.
In the operating theatre, an intra-arterial
catheter was inserted into her left radial
He had a modified Allen’s test per-
formed pre-operatively with normal
results, indicating a patent ulnar artery.
In the the operating theatre, his left
radial artery was cannulated without
difficulty. No hypotension occurred
during the procedure and the cannula
was left in situ for 4 h. On the seventh
postoperative day, after another general
anaesthesia that did not require direct
artery. The surgery lasted 4 h. During Figure 5
1
034
Ó 2003 Blackwell Publishing Ltd

Anaesthesia, 2003, 58, pages 1023–1045
Correspondence
....................................................................................................................................................................................................................
.
intra-arterial blood pressure monitoring, predicting the ischaemic complication
he became hypotensive with systolic following the radial artery cannulation.
sitating amputation after radial artery
cannulation. Canadian Journal of
Anaesthesia 1993; 40: 247–50.
blood pressure down to 75 mmHg in
Cardiac surgeons have developed
the ward. He then developed a blue renewed interest in the circulation of 4 Nunoo-Mensah J. An unexpected
discoloration and pain in his left thumb the hand because of the use of radial
and index finger. No treatment was artery grafts for coronary artery bypass.
given and the discoloration and pain There are many studies on different
resolved spontaneously over the next techniques for assessing hand circula-
complication after harvesting of the
radial artery for coronary artery bypass
grafting. Annals of Thoracic Surgery 1998;
66: 929–31.
2
weeks. He recovered with no func- tion, including the Allen’s test, Doppler 5 Bowdle TA. Complications of invasive
tional disability or symptoms in the left ultrasound, pulse oximetry, digit blood
hand. The radial pulse was, however, pressure and colour-flow Doppler. One
still not palpable when the patient was case report described acute ischaemia of
followed up 1 year postoperatively. the hand after coronary artery bypass
monitoring. Anesthesiology Clinics of
North America 2002; 20: 333–50.
This case report is interesting in that grafting with a radial artery conduit [4]. Remifentanil infusion
no ischaemic complication relating to The modified Allen’s test performed calculation made simple
radial artery cannulation was noted until pre-operatively was normal. The isch-
7
days after decannulation and it devel- aemia occurred 2 days after the opera- The use of remifentanil by infusion
oped following a period of hypotension tion at the time of onset of atrial should not be totally reliant on a flow
after the second operation. In this fibrillation. The ischaemia improved rate calculated by an infusion device.
patient, thrombosis in the cannulated after the patient had reverted into sinus Being able to calculate the flow rate
radial artery was likely to have devel- rhythm and a revascularisation opera- oneself allows verification of the dev-
oped after the first operation. The tion with a venous graft was subse- ice settings, or the use of a simple syr-
thrombosis did not cause any ischaemic quently performed.
inge driver. Like your correspondent
consequence until the patient devel- Invasive monitoring during anaesthe- (Chelliah. Anaesthesia 2003; 58: 104), I
oped hypotension. The normal Allen’s sia is relatively safe [5]. Radial artery have had an occasion on which the flow
test was not able to predict the throm- catheterisation has a very low rate of rate set to be delivered by the infusion
bosis or the subsequent ischaemia.
serious complications. Although throm- device (a Graseby 3500 syringe driver)
Mangar et al. [3] presented a case of bosis following radial artery catheterisa- did not correspond to the desired drug
ischaemic hand injury in a 35-year-old tion is common, it very rarely leads to infusion rate. In this case, the flow rate
patient scheduled for right femoral–tibial ischaemic complications. However, the was five times too fast. The infusion was
bypass under general anaesthesia, follow- ischaemic risk is enhanced in patients not commenced, as the mentally calcu-
ing an atraumatic placement of a left with peripheral vascular disease and lated flow rate did not match the pump
radial artery catheter. He had a compli- hypotension in the postoperative per- flow rate, which was five times too fast.
cated past medical history of insulin- iod. The two cases we reported had The cause remains unknown as the
dependent diabetes mellitus for 25 years, vascular pathology and were hypoten- printout retrieved from the pump
)1
end-stage renal disease, coronary artery sive, requiring inotropic support in the confirmed the infusion rate in lg.kg .
disease, silent myocardial infarction, per- postoperative period. It is therefore of min without reporting the rate in
)
1
)
1
ipheral vascular disease, hypertension paramount importance that the inten- ml.min . Even if the machine makes
and left hemispheric cerebrovascular sive care staff are aware of the risk and the correct calculation, it is dependent on
accident. The Allen’s test in him was keep a high level of vigilance in the correct information being entered,
equivocal: 12–15 s return of blood after vulnerable patients.
ulnar artery release with palmar blush
A. Y. C. Wong
from which to make the calculation, so
human error cannot be avoided.
My calculation method is very simple
indeed and thus reduces error.
return to baseline. He had an uneventful
A. M. O’Regan
general anaesthetic and accidentally
Queen Mary Hospital,
pulled out the radial artery catheter on
Hong Kong
the following morning. On the 10th day,
• Prepare remifentanil to a concentra-
)1
tion of 60 lg.ml (2 mg diluted to
33.3 ml).
E-mail: ayc_wong@hotmail.com
he complained of pain, coldness and
discoloration in his left hand. Anticoag-
ulation therapy was started. Unfortu- 1 Slogoff S, Keats AS, Arlund C. On the
References
• Divide the patient’s body weight in
kg by 10.
)
1
nately, 3 weeks later, he required hand
amputation. The authors agreed that
patients might develop ischaemic injury 2 Arthurs GJ. Case report: digital isch-
safety of radial artery cannulation.
• This gives the rate in ml.h
to
)1
)1
Anesthesiology 1983; 59: 42–7.
deliver 0.1 lg.kg .min .
Once this basic rate is established,
if adverse conditions are present for long
enough, e.g. hypotension, use of vaso-
pressors and multiple particulate emboli
arising from within the heart. Again, in 3 Mangar D, Laborde RS, Vu DN.
this case, Allen’s test was not useful in
aemia following radial artery cannula-
higher or lower rates can be calculated by
tion. Anaestheisa and Intensive Care 1978; simple multiplication or division of the
6: 54–5.
rate. For example, a patient weighing
72 kg requires an infusion rate of
)1
)1
)1
Delayed ischaemia of the hand neces-
7.2 ml.h to deliver 0.1 lg.kg .min ,
Ó 2003 Blackwell Publishing Ltd
1035

Correspondence
Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
)1
an infusion rate of 14.4 ml.h to deli- lorazepam. The patient’s behaviour
of Anaesthesia, 6th edn. London:
Edward Arnold, 1995, 601–20.
to deliver later, the patient was rescheduled for the 2 Ong BY, Pickering BG, Palahniuk RJ,
)1
)1
ver 0.2 lg.kg .min , or an infu- became normal after 8 h. Two days
)
1
sion rate of 3.6 ml.h
)1
)
1
0
.05 lg.kg .min .
I have used this method for well over premedication for obvious reason. Sur-
a year and apart from saving one gery was conducted under spinal anaes-
potential critical incident it allows the thesia uneventfully and lasted 80 min.
same operation and was not given any
Cumming M. Lorazepam and diazepam
as adjuncts to epidural anaesthesia for
caesarean section. Canadian Anaesthetic
Society Journal 1982; 29: 31–4.
calculating pumps to be available to The patient had an uneventful recovery. 3 Reves JG, Glass PSA, Lubarsky DA.
colleagues who require them.
Benzodiazepines are frequently used
for premedication because of their
hypnotic, sedative, anxiolytic and
amnesic properties. Confusion, bizarre
behaviour, amnesia, agitation and hal-
lucinations are reported in the elderly
Nonbarbiturate intravenous anesthetics.
In: Miller RD, ed. Anesthesia, 4th edn.
New York: Churchill Livingstone Inc.,
1994, 247–90.
P. J. A. Lesser
The Calderdale Royal Hospital,
Halifax HX3 0PW, UK
E-mail: piers.lesser@cht.nhs.uk
Solvents in pregnancy: an
emerging problem in obstetrics
and obstetric anaesthesia
after treatment with triazolam,
a
Pre-operative psychosis
following oral lorazepam
benzodiazepine [1]. Further, Ong et al.
reported delirium, hallucination, con-
fusion and agitation following intra-
venous administration of lorazepam
We report an unusual cause of acute
psychosis and violent agitation following
premedication with oral lorazepam. A
Although the use of Ômajor leagueÕ
recreational drugs, such as cocaine
and amphetamines, in pregnancy has
received significant attention over the
past two decades [1, 2], limited attention
has been given to the consequences of
maternal use of solvents, which are by
far the most easily obtainable substances
for illicit use. Additionally, although the
deleterious effects of cocaine or amphet-
amines on the mother and the fetus are
more pronounced and easier to detect,
the addiction to solvents is usually subtle
and more difficult to diagnose. As a
result, recreational solvents use may
continueundetected, significantlyeffect-
ing pregnancy outcome and obstetric
and anaesthetic management of these
patients [3].
The (limited) literature concerning
maternal and fetal implications of sol-
vents use in pregnancy is focused exclu-
sively on deleterious effects of chronic
drug ingestion [4–6]. To date, no reports
have addressed the management of
obstetric and anaesthetic emergencies
resulting from acute maternal solvents
intake; I herein present such a case.
A 30-year-old, 167-cm, 64-kg, grav-
ida 1, para 0, female with a history of
bipolar disorder at 32 weeks gestation
was admitted to the labour and delivery
(L & D) suite for an emergency (crash)
Caesarean section as a result of solvent-
related maternal respiratory depression
and fetal bradycardia. The patient had
been found lying in her house with
a plastic bag over her head sniffing
Ôhousehold chemicalsÕ from a soaked
rag. Although she had nearly suffocated
)
1
(
0.05 mg.kg ), in patients undergoing
Caesarean section under epidural anaes-
thesia [2]. However, in the present case,
the patient was elderly and received oral
lorazepam that caused an adverse event
that led to the postponement of surgery.
The condition was self-limiting as was
evident in the present case.
The pharmacokinetics of lorazepam is
little affected by age, gender and renal
disease [3], and hence is used frequently
as a premedicant for different procedures.
However, we suggest that following
administration of oral lorazepam, espe-
cially in the elderly, the patient should be
carefully watched for changes in beha-
viour during the pre-operative period. In
the event of acute psychosis following
lorazepam administration, the drug
should not be re-administered. To avoid
the recurrence of such an adverse event,
this same should be reported on the
anaesthesia record.
7
0-year-old, 68-kg male presented for
transurethral evaporation of prostate.
Past history revealed nothing significant
in relation to major systemic illness, drug
allergy or adverse effects, and psychoso-
matic disorder. Pre-operative investiga-
tion consisted of full blood count, and
blood chemistry for urea-nitrogen, cre-
atinine and liver enzymes, which were
found to be within normal limits. The
serum prostate-specific antigen titre
)
1
(
PSA) was 3.8 ng.ml . American uro-
logical association symptom index for
benign prostatic hypertrophy was
1
9 ⁄ 35. On pre-operative visit, the
patient was calm, cooperative and relat-
ively free from anxiety. The general
condition was good along with normal
higher mental function. The patient was
not on any medications pre-operatively.
The patient received oral lorazepam
2
mg 90 min before the scheduled
P. K. Sinha
operation. Seventy-five minutes after
oral lorazepam administration, the
patient started showing grossly dis-
organised and agitated behaviour and
became violently psychotic with irre-
levant commentary. This led to the
postponement of the surgical proce-
dure. After ruling out other possibilities
such as deranged renal function, elec-
trolyte imbalance and hypoglycaemia,
neurological consultation was sought,
Sree Chitra Tirunal Institute for
Medical Sciences & Technology,
Thiruvananthapuram, Kerala 695011,
India E-mail: pksinha@sctimst.ac.in
S. P. Ambesh
Sanjay Gandhi Postgraduate Institute of
Medical Sciences,
Lucknow, India
References
which revealed no abnormality. How- 1 Roizen MF, Lichtor JL. Preoperative
ever, psychiatric consultation revealed
that the patient’s bizarre behaviour was
most probably caused by the oral
assessment and premedication for
adults. In: Healy TE, Cohen PJ, eds.
Wylie and Churchill-Davidson’s a Practice
1
036
Ó 2003 Blackwell Publishing Ltd

Anaesthesia, 2003, 58, pages 1023–1045
Correspondence
....................................................................................................................................................................................................................
.
herself, she remained haemodynamic- ance, pulmonary hypertension, acute obstetric and obstetric anaesthesia emer-
ally stable. respiratory distress syndrome and liver gencies will increase.
The patient was taken to the oper- toxicity have all been reported in preg-
ating room, positioned on the operating nancy with documented exposure to
room table in the left-tilt position, anaes- solvents [3–5].
K. M. Kuczkowski
UCSD Medical Center,
San Diego, CA 92103–8770, USA
E-mail: kkuczkowski@ucsd.edu
thesia monitors were applied, and the
Toluene sniffing for recreational pur-
gravid abdomen was prepared for sur- poses in pregnancy has been associated
gery with iodine solution. The lungs with an increased incidence of intra-
were denitrogenated with 100% oxygen uterine fetal growth restriction, preterm
References
1
Andres RL. Social and illicit drug use in
pregnancy. In: Creasy RK, Resnik R,
eds. Maternal–Fetal Medicine. Philadel-
phia: W.B. Saunders Company, 1999,
145–64.
(
four vital capacity breaths). Rapid delivery and prenatal mortality [3–5].
sequence induction of general anaes- Although Hersh raised the possibility of
thesia was performed in a standard toluene embryopathy and fetal solvent
manner with intravenous etomidate syndrome, the evidence was inconclu-
)
1
0
.2 mg.kg followed by succinylcho- sive and the fetal solvent syndrome was
)
1
2 Kuczkowski KM. Drug abuse in preg-
nancy – anesthetic implications. Progress
in Anesthesiology 2001; 25: 355–72.
line 1.5 mg.kg while cricoid pressure never defined [6]. Toluene may aug-
was continuously applied, and the tra- ment the manifestations of fetal alcohol
chea was intubated. A 1150-g female syndrome in parturients abusing both
neonate (Apgar scores of 3 and 7 after 1 substances simultaneously.
3
4
5
Jones HE, Balster RL. Inhalant abuse in
pregnancy. Obstetric and Gynecology
Clinics of North America 1998; 25:
and 5 min, respectively) was delivered
Optimal obstetric and anaesthetic
via the Caesarean incision. Surgery was management of solvent-misusing partu-
promptly completed and the patient was rients requires a high level of suspicion
taken to the postanaesthesia care unit and early diagnosis. Altered perception
intubated. There were no postoperative of sensory stimuli, loss of coordination,
sequelae, she was extubated 50 min headache, nausea, vomiting and respir-
after the surgery end and her postpar- atory compromise may result from
tum course was uneventful. Postopera- vapour sniffing. Careful physical exam-
tively, the neonate was diagnosed with ination including determination of
growth restriction and the patient possible sensory or motor deficits is
admitted to regular (recreational) indicated prior to induction of labour
household solvents sniffing throughout analgesia or surgical anaesthesia for
1
53–67.
Wilkins-Haug L, Gabow PA. Toluene
abuse during pregnancy: obstetric
complications and perinatal outcomes.
Obstetric Gynecology 1991; 77: 504–9.
Cunningham SR, Dalzell GWN,
McGirr P et al. Myocardial infarction
and primary ventricular fibrillation after
glue sniffing. British Medical Journal
1
987; 294: 739–40.
6
Hersh JH. Toluene embryopathy: two
her pregnancy.
abdominal delivery [2]. Both regional
new cases. Journal of Medical Genetics
In the United States, nearly a million and general anaesthesia in the solvents-
people, of whom 70% are young adults, misusing parturient may be associated
misuse inhalants [2]. Inhalants include a with intrapartum and ⁄ or intra-opera-
1
989; 26: 333–7.
chemically diversified group of sub- tive complications. When regional Acute respiratory syndrome
stances such as organic solvents and anaesthesia is selected, combative beha- associated with extreme
volatile agents that affect the central viour and altered pain perception may Superpruf aerosol
nervous system. Toluene is a commonly be encountered. Cardiac arrhythmias
used industrial solvent and a major and labile blood pressures may be A 55-year-old male taxi driver was
component in many household paints encountered under general anaesthesia. referred to us for intensive care and
and cleaning agents. Solvents may be In acutely intoxicated parturients, respiratory support. The patient had
sniffed from soaked rags, bags or open administration of general anaesthesia presented at the referring hospital’s
containers, as well as ingested orally for for operative delivery may be necessary. A & E department with a history of
their narcotic effects.
By definition, substance misuse is being found, by his mother, confused
Solvent inhalation causes intense cen- described as Ôself-administration of var- and drowsy. According to the mother
tral nervous system stimulation and ious drugs that deviate from medically who lives with the patient, he had gone
disinhibition similar to alcohol inges- or socially accepted use, which if pro- to bed the previous night in good
tion. Toluene sniffing may lead to longed can lead to the development of health. He had no previous physical
autonomic cardiac dysfunction, ventric- physical and psychological dependenceÕ. illness or psychiatric illness, was taking
ular fibrillation and myocardial infarc- Psychological personality characteristics no medication, was a lifelong smoker
tion. Glue sniffing can cause a unique seem to predispose to, rather than and drank very little alcohol. He did not
distal and proximal tubular acidosis. result from, drug addiction. Because of have any pets and there was no history
Chronic exposure to toluene vapours the increasing prevalence of recre- of any recent travel.
has been reported to cause changes in ational drug use (including solvents)
On examination at the referring
the central nervous system such as among young women (including in hospital, he was found to be drowsy,
diffuse brain atrophy and cerebellar pregnancy), it is reasonable to expect confused, agitated and tachypnoeic and
degeneration. Increased airway resist- that the incidence of solvent-related did not tolerate an oxygen mask or a
Ó 2003 Blackwell Publishing Ltd
1037

Correspondence
Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
CPAP mask. His temperature was waterproof aerosol spray on his hat in a increased surveillance and vigilance of
6.4 °C, respiratory rate 38 breath. confined space. He either inhaled or similar products and incidents.
We searched the medical literature
3
min , pulse rate of 90 beat.min in ingested some of this agent, became sick,
)1
)1
sinus rhythm and a normal blood pres- vomited and lost consciousness to be for respiratory insufficiency and fluoro-
sure. Glasgow Coma Scale (GCS) was found by his mother some hours later. carbons, but were unable to trace any
13 ⁄ 15, there was no neck stiffness or The patient was resedated and a bron- previous reports of ARDS following
photophobia and he was moving all limbs choscopy done later showed a markedly exposure to these products.
equally with normal reflexes. Fundo- inflamedtracheobronchialtreeextending The patient developed progressive
scopy was not possible owing to his to the limits of vision, associated with impairment of gas exchange and was
agitated state. His heart sounds were areas of mucosal sloughing. referred to a tertiary centre for further
normal with no murmurs, and his JVP The family later brought in the can of care but unfortunately he died of
was not raised. Chest auscultation re- the spray that the patient had used, and respiratory failure and a post-mortem
vealed extensive bilateral crepitations the offending agent was identified. The examination was not performed.
and a chest radiograph showed bilateral product is marketed as EXTREME
M. S. Malik
pulmonary infiltrates in keeping with SUPERPRUF AEROSOL SPRAY,
B. Chappell
acute lung injury. Arterial blood gasses which is a blend of fluro copolymer in
)
1
Crawley Hospital,
on 100% oxygen at 16 l.min were as isoparaffinic hydrocarbons used as a
follows. Pa 8.5 kPa, PaCO 3.76 kPa waterproofing agent. We accordingly
and a pH of 7.39. Other blood results requested information from the manu-
Crawley RH11 7DH, UK
E-mail: sohailm29@hotmail.com
O
2
2
)
1
showed a raised urea of 12.2 mmol.l , facturers. On review of the product
6
)1
CRP 138, WCC 12.5 · 10 .l , normal safety data sheet, we found that the agent An evaluation of safety
electrolytes and blood glucose of can cause lung damage if swallowed and of storage practices of laryngeal
)
1
9
.8 mmol.l . The patient was given inhalation of the vapours in high con- mask airways and tracheal
ceftriaxone 4 g and of clarythromycine centration may also cause irritation of the tubes
g and these antibiotics were to be respiratory system. Symptoms of inhala-
continued. tion may manifest with headache, dizzi- In our hospital, the laryngeal mask
At this stage, the patient was not ness, lethargy, nausea and vomiting. airways were unpacked after sterilisation
tolerating CPAP and, with a deterior- We contacted the National Poisons and stored in drawers and cupboards.
1
ating gas exchange, a decision was made Information Service at the Guy’s and The tracheal tubes were removed from
to ventilate the patient. He was intu- St Thomas’s Hospital for any further their sterile packs before the start of the
bated and ventilated, sedated with information and guidance. They repor- operating lists in readiness for an emer-
propofol and fentanyl and a CT scan ted that they have recently become gency. KY-Jelly-soaked green swabs
of the head was performed, which aware of a number of reports of were used to lubricate the tracheal tubes
showed no abnormality. Owing to a poisoning after the use of waterproofing and laryngeal masks. We investigated
local shortage of ICU beds, the patient products. The information has come whether contamination of this airway
was transferred to the intensive care unit from poisons centres in Europe, partic- equipment was a possibility.
at Crawley Hospital.
ularly the Netherlands and Switzerland.
Tracheal tubes, laryngeal masks,
A lumbar puncture was performed, Clinical effects vary from mild symp- KY-Jelly-soaked swabs and drawers
which showed an elevated opening toms (coughing for several hours) to and cupboards where these were stored
pressure but was otherwise entirely severe pulmonary reactions with oede- were randomly sampled from four
normal. At this stage, the provisional ma. In most of these cases, people used operating theatres and were subjected
working diagnoses were viral encephal- the sprays indoor often in small rooms, to appropriate microbiological cultures
itis and aspiration leading to acute lung as was the case in our patient. The (Fig. 6).
injury (ALI ⁄ ARDS) and acyclovir and products involved contained fluorocar-
metronidazole were added to the cur- bon resins, butane and hydrocarbons.
Bacterial growth representing skin and
environmental flora was obtained from
rent treatment.
The next morning, he remained ven- nation of various fluorocarbon com- drawers, shelves and green swab, except
tilator-dependent with Fi of 0.55 and pounds that causes the pulmonary for one tracheal tube (Table 3, Fig. 7).
It seems likely that it is the combi- all the laryngeal masks, tracheal tubes,
O
2
Pa
O
of 10 kPa on 10 cm of PEEP. In problems, but the reason for this is
The manufacturers of laryngeal masks
2
line with our local sedation policy, unclear. It may be that because of the recommend that these should be steri-
sedation was stopped in order to assess finer aerosols, the fluorocarbons are lised after each use but there is no
neurological function. As the patient carried deeper into the pulmonary tract, advice about their storage. Tracheal
woke up, he tolerated the tracheal tube especially if exposure is prolonged. The tubes come in sterile sealed packs and
well and was able to communicate with treatment of pulmonary (ARDS) and it is recommended that these should be
the nursing and medical staff by writing. other problems is essentially supportive. unpacked just prior to use.
A big piece in the puzzle now fell into The current position of the National
The Association of Anaesthetists of
place. He gave a history of using a Poisons Centre is that they have Great Britain and Ireland in their recent
1
038
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....................................................................................................................................................................................................................
.
Figure 6 The airway equipment and the storage sites sampled.
booklet ÔInfection Control in Anaesthe- patients, of which four blood cultures within the United Kingdom. Removal
siaÕ [1] does not mention storage prac- were positive. of tracheal tubes from their packs in
tice after sterilisation of laryngeal masks. These studies suggest that airway readiness for use in emergency situa-
Similarly, the Royal College of Anaes- manipulation with laryngeal masks and tions, whilst understandable, resulted in
thetists does not provide any such tracheal tubes may lead to bacteria a large number of tracheal tubes poten-
guidance. However, both the Australia entering the bloodstream either from tially being exposed to room air and the
and New Zealand College of Anaes- the patient’s own flora or from the surfaces of anaesthetic machines. Our
thetists [2] and the Hong Kong College surface of the airway devices. There results show that our practice resulted in
of Anaesthetists [3] clearly recommend may be an increased risk of bacterial significant bacterial contamination. We
that laryngeal masks as well as tracheal transmission if the devices are used have changed our practice; laryngeal
tubes and nasal and oropharyngeal air- un-sterile. Insertion of contaminated masks are now sterilised and then packed
ways should be kept sterile until used.
Stone et al. [4] have described tran- result in colonisation with new and laryngeal masks are opened just
sient bacteraemia after airway manipu- organisms. prior to use. The use of green swabs to
lation with clean laryngeal masks and We were unable to elucidate why the lubricate tubes and laryngeal mask
devices in the patient’s airway could individually. The packs of tracheal tubes
tracheal tubes. In this study, the bacteria practice in our department involved airways has also been abandoned. In
isolated represented patients’ resident removing laryngeal masks from their addition, we feel that there is a need for
flora. Brimacombe et al. [5] have also sterile packs for storage prior to use; clear guidelines on storage practices of
studied bacteraemia following insertion perhaps it was because there are no clear laryngeal masks and tracheal tubes in
of laryngeal mask airways in 100 fit recommendations in this area from the UK.
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Anaesthesia, 2003, 58, pages 1023–1045
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.
Table 3 The sites sampled and the bacterial growth obtained.
No.
Samples
Results
1
2
3
4
5
Laryngeal masks from 4 sites
Light to heavy growth of Bacillus, Staphylococcus epidermidis and Micrococci
Bacillus, Staphylococcus epidermidis and Streptococcus viridans
Light growth of Bacillus, Staphylococcus epidermidis
Light to moderate growth of Bacillus, Staphylococcus epidermidis and Micrococci
No growth
Tracheal tubes from 2 sites
Green swab KY Jelly from 1 site
Laryngeal mask drawers and shelves from 3 sites
Tracheal tube from 1 site
Figure 7 Broth bottles show turbidity due to bacterial growth from tracheal tubes, except the one marked by an arrow, and contact plate showing
bacterial colonies from a laryngeal mask.
K. Z. Khan
5 Brimacombe J, Shorney N, Swainston
R, Bapty G. The incidence of bacter-
aemia following laryngeal mask inser-
infection such as hepatitis A or B, or
HIV. Would I be prepared to inject
the remaining contents of any part of
M. West
R. J. Vickers
Queens Hospital,
Burton on Trent DE13 0RB, UK
E-mail: drkamran@wol.net.pk
tion. Anaesthesia and Intensive Care 1992; that equipment into another patient?
20: 484–6.
No, certainly not, no matter how
many lengths of tubing or one-way
valves were changed. I certainly would
not want it injected into me or a
member of my family. I do not have
evidence to confirm this prejudice, but
gut feelings do not come any stronger,
Re-use of equipment between
patients receiving total
References
1
2
3
4
AAGBI. Infection Control in Anaesthesia.
London: The Association of Anaes-
thetists of Great Britain and Ireland,
intravenous anaesthesia
I was astonished that Halkes & Snow and I would not do to a patient what I
found that only 46% of the consultants would not accept for myself. As it is
in their survey change all equipment for not generally possible to be sure that
total intravenous anaesthesia (TIVA) any patient is free from one of these
between cases (Halkes & Snow. Anaes- infections, the only acceptable practice
2
002.
Anon. Policy of Infection Control in
Anaesthesia.Sydney: Australia and
New Zealand College of Anaesthetists,
1
995, 28.
thesia 2003; 58: 582–7).
When prefilled,
is to treat all patients as if they were
electronically infected, and I suggest that Halkes &
Anon. The Guidelines on Infection Control
in Anaesthesia. Hong Kong: The Hong
Kong College of Anaesthetists, 1997,
tagged, propofol syringes were intro- Snow’s assertion that all of the infu-
duced some years ago, their expense sion equipment should be discarded
became a consideration. I decided to between cases is indisputable.
1
5.
Stone JM, Karalliedde LD, Carter ML,
Cumberland NS. Bacteraemia and
insertion of laryngeal mask airway.
Anaesthesia 1992; 47: 77.
base my own practice on what I would
I retired several years ago, and if I
do if I used TIVA equipment for a ever make another appearance in an
patient whom I knew to have an operating theatre it will be as a patient,
1
040
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....................................................................................................................................................................................................................
.
not as an anaesthetist; I hope no-one and has been demonstrated as an effect- guaranteed. Information from the
re-uses any TIVA equipment on me.
ive and safe method to facilitate para- regional poisons unit suggested that
thyroidectomy [1, 2]. However, we plasma levels are not known to be
report a case of a 60-year-old woman clinically useful.
R. L. Marshall
Glasgow G77 5RW, UK
E-mail: robinmarshall1939@
hotmail.com
who had an adverse neurological
event following the use of intravenous following morning in order to facilitate
methylene blue. a CT head scan, which was normal. On
This patient, scheduled for a para- the second postoperative morning, the
thyroidectomy, had symptomatic sedation was stopped and the patient
The patient was re-intubated the
Transient hearing loss
with labour epidural block
hypercalcaemia secondary to a parathy- extubated without incident. She remai-
roid adenoma, and a history of anxiety ned intensely blue-stained and had dark
I read with interest the case of auditory and depression. Her only medications blue urine for 3 days. Her corrected
dysfunction after epidural injection dur- were fluoxetine, coproxamol and calcium stayed within the normal range,
ing labour (Rajaesekaran et al. Anaesthe- beclamethasone nasal spray. She had and her haemoglobin dropped from a
)1
sia 2003; 58: 613–14). Transient hearing no known allergies and had undergone pre-operative value of 14.7 to 9.7 g.dl ,
loss after epidural injection has been one previous general anaesthetic for which was attributed to haemodilution.
reported previously [1, 2]. The mech- tonsillectomy with no adverse effects. There was no evidence of haemolysis.
anism of action is straightforward. The Pre-operatively, she was administered
a
Over the following 2 days her speech
methylene blue infusion of and neurological status returned to
lymphatic and subarachnoid spaces allo- 7.5 mg.kg . She vomited once during normal. After a normal MRI scan on
wing passage of tracer from one to the its administration and, on arrival in the the fourth day, she made a full recovery,
other [3]. Perilymph in the inner ear is anaesthetic room, looked very blue but and was discharged to the ward before
in continuity with cerebrospinal fluid so showed no abnormal behaviour. Sur- returning home.
cochlear canaliculus connects the peri-
)
1
that any pressure wave within the gery was carried out uneventfully under
Despite many years of apparent
subarachnoid space is conducted general anaesthesia during which all her innocuous use of intravenous methy-
directly through to affect the basement vital signs remained within the normal lene blue, it has definite toxic effects.
membrane [4]. The surprising fact is range. At the end of the procedure, the Nadler et al. [3] found that intravenous
that this phenomenon is not reported patient was extubated and transferred to methylene blue excited the individual,
more often.
the recovery room.
and by its rapid elimination into the
Shortly after arrival in recovery, she stomach and urine produced transitory
was noted to have rotational nystagmus gastrointestinal and urinary irritation.
and dilated pupils that were unreactive The most frequent toxic symptoms
to light. Thirty minutes later, she began observed were restlessness, paraesthesia,
to display rigid, jerky movements of all burning sensation and chest pain, all of
four limbs and remained very agitated which subsided in 24–48 h. A number
over the subsequent 2 h with a fluctu- of individuals also complained of dizzi-
ating Glasgow Coma Scale (GCS) of ness, headache and mental confusion, all
P. A. J. Hardy
Gloucestershire Royal Hospital,
Gloucester GL1 3NN, UK
E-mail: paulajhardy@lineone.net
References
1
2
3
4
Hardy PAJ. Hypoacousis following
extradural injection. British Journal of
Anaesthesia 1986; 58: 573.
7–10. She had increased tone in all of which completely resolved.
four limbs, bilateral up-going plantar The UK National Poisons Informa-
Hardy PAJ. Blocked ear after extradural
injection. British Journal of Anaesthesia
reflexes, was noted to be sweating tion Service (Cardiff Centre) recom-
profusely and flushed above the shoul- mend an intravenous dose not
)
1
1
987; 59: 667.
ders, yet remained haemodynamically exceeding 4 mg.kg of a 1% solution
stable. An arterial blood gas revealed a and list similar potential signs and symp-
respiratory acidosis with a PCO of toms of toxicity, namely nausea and
Warwick R, Williams PL, eds. Grays
Anatomy, 35th edn. London: Longman,
2
1
973, 1148–9.
6
0.1 mmHg, PCO 103 mmHg and an vomiting, abdominal pain, precordial
2
)1
Hardy PAJ. Influence of spinal punc-
ture and injection on V111 nerve
function. Journal of Laryngology and
Otology 1988; 102: 452.
ionised calcium level of 1.49 mmol.l . pain, headache, hypertension, profuse
It was decided to transfer her to the sweating, restlessness and confusion.
intensive care unit for closer observa- They also state that methylene blue itself
tion where she appeared to improve may cause methaemoglobinaemia (up to
initially, but became more agitated and 7%) when given in very large doses, but
aggressive overnight. The maximum that this amount of methaemoglobin
methaemoglobin level in arterial blood (MHb) is clinically insignificant.
Neurological sequelae
following methylene blue
injection for parathyroidectomy gases reached 0.7% on admission to the
Another authority reports that if
ICU. A methylene blue blood level methylene blue intravenous dosage
)1
Intra-operative staining of the parathy- obtained from blood taken 6 h postop- exceeds 7 mg.kg , the same adverse
roid glands with intravenously adminis- eratively was reported as very low but symptoms may result [4]. Yet staining
tered methylene blue is well described the validity of the result could not be abnormal parathyroid glands with
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Anaesthesia, 2003, 58, pages 1023–1045
....................................................................................................................................................................................................................
.
)
1
7
tered methylene blue is common prac- important to remember that no dye or port
.5 mg.kg of intravenously adminis- the most likely cause. In summary, it is anaesthetic emergencies. I herein re-
case of parturient who
a
a
tice among surgeons and we have been drug given to a patient either intra- presented with placental abruption
unable to find reports of toxicity in the operatively or postoperatively should be and fetal distress following acute
literature associated with this dose.
regarded as inconsequential, and indis- ÔcrackÕ cocaine intake and required
The picture presented could be criminate use of methylene blue in emergency Caesarean section, which
explained by the hypoxaemia caused by doses above those recommended may was conducted under uneventful sin-
methaemoglobinaemia. However, it is produce unpleasant results and may be gle-dose spinal anaesthesia.
unusual for MHb levels of less than 20% dangerous to the patient.
to be associated with hypoxic symptoms
S. J. Martindale
A 26-year-old, 167-cm, 66-kg, grav-
ida 1, para 0, otherwise healthy female
with a history of multiple-substance
misuse at 30 weeks gestation required
emergency Caesarean section as a result
of crack cocaine-induced placental ab-
ruption and fetal distress. She had no
known drug allergies and no prior
anaesthesia. The course of her preg-
nancy had been ÔuneventfulÕ; specific-
ally, there were no symptoms of
pregnancy-induced hypertension; how-
ever, she admitted to recreational mul-
tiple-substance intake including cocaine,
heroin and alcohol. Her admission
blood pressure was 145 ⁄ 95 mmHg,
such as confusion, and in individuals with
J. C. Stedeford
normal amounts of haemoglobin (Hb),
Bristol Royal Infirmary,
an MHb level of less than 20% usually
Bristol BS2 8BJ, UK
only causes cyanosis [5]. Our patient had
)
1
E-mail: sjmartindale@doctors.org.uk
E-mail: judithstedeford@hotmail.com
a pre-operative Hb of 14.7 g.dl and the
maximum MHb present at the height of
symptoms was only 0.7%. We are there-
fore led to conclude that the observed
decrease in Hb was not proportional to
the intensity of the symptoms, unless it
could be argued that the reversibility
of this reaction is almost immediate.
Indeed, the reconversion rate of MHb to
haemoglobin in normal individuals is
about 15% per hour, assuming no
ongoing MHb production [6].
References
1
2
3
Derom AF, Wallaert PC, Janzing HM,
Derom FE. Intraoperative identification
of parathyroid glands with methylene
blue infusion. American Journal of Surgery
1
993; 165: 380–2.
Devine RM, Van Heerden JA, Grant
CS, Muir JJ. The role of methylene
blue infusion in the management of
persistent or recurrent hyperpara-
thyroidism. Surgery 1983; 94: 916–18.
Nadler JE, Green H, Rosenbaum A.
Intravenous injection of methylene
blue in man with reference to its toxic
symptoms and effect on the electro-
cardiogram. American Journal of Medical
Science 1934; 188: 15–21.
)1
heart rate 95 beat.min and respiratory
)1
rate 20 breath.min . Fetal heart rate
)1
Furthermore, if this clinical picture
was brought about by acute hypoxae-
mia, we would have expected to see a
more marked effect on respiration and
circulation, whereas the primary effect
seemed to be a neurological one. We
are led to conclude that the harmful
effects of methylene blue may not be
associated primarily with methaemo-
globin, but rather attributed to the
direct action of the drug itself.
A further possible explanation might
be a neuroexcitatory response to prop-
ofol. There are a number of reported
cases of hypertonia, opisthotonus, jerky
movements and seizures occurring in
otherwise healthy individuals after an
anaesthetic involving intravenous prop-
ofol [7]. Whilst some of the features
seen in this case would be consistent
with an adverse response to propofol, it
would not explain the profuse sweating
and sense of apprehension seen in this
patient. Furthermore, the patient was
sedated with propofol on the intensive
was 130 beat.min and non-reactive,
with late and variable decelerations and
no response to maternal oxygen admin-
istration. The maternal physical exam-
ination conducted by the obstetrician
documented uterine tenderness, and the
reading of the external pressure-
sensitive tocodynamometer recorded
uterine hypertonicity. Obstetric ultra-
sound documented a single fetus in
cephalic presentation with intra-uterine
growth restriction without any gross
abnormalities. However, the presence
of a hypoechoic area representing ret-
roplacental bleeding (haematoma) caus-
ing separation of the placenta from
decidua basalis was discovered. Labor-
atory coagulation studies were normal.
The working diagnosis of acute placen-
tal abruption with fetal distress was
established and emergency Caesarean
delivery was indicated. Although the
patient was slightly agitated, she cooper-
ated with obstetric and anaesthetic rec-
ommendations. An intravenous fluid
preload with crystalloid solution (Lac-
4
5
Anon. AHFS Drug Information. AHFS,
2
002.
Wright RO, Lewander WJ, Woolf AD.
Methemoglobinemia: etiology, phar-
macology, and clinical management.
Annals of Emergency Medicine 1999; 34:
6
46–55.
6
7
Finch CA. Treatment of intracellular
methaemoglobinaemia. Buletin of New
England Medical Center 1947; 6: 241–5.
Islander G, Vinge E. Severe neuroex-
citataory symptoms after anaesthesia –
with focus on propofol anaesthesia. Acta
Anaesthesiologica Scandinavica 2000; 44:
1
44–9.
care unit for 24 h, during which time Caesarean section in a cocaine-
her symptoms improved. intoxicated parturient: regional tated Ringer’s solution) was initiated
Thus, although we cannot give con- vs. general anaesthesia?
clusive evidence that this patient’s
and the patient was taken to the oper-
ating room. A spinal block, with 12 mg
symptoms were wholly a result of the The illicit use of cocaine in pregnancy bupivacaine 0.75%, fentanyl 5 lg and
high dose of methylene blue, it remains has been associated with obstetric and morphine 0.2 mg at the L2–3 inter-
1
042
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....................................................................................................................................................................................................................
.
space, was induced with the patient in cocaine-intoxicated parturients. The
the sitting position. A T4 sensory level decision to perform spinal anaesthesia
was established and surgery began. A for Caesarean section in this case was
1
250-g female fetus with Apgar scores based on maternal and fetal haemody-
of 5 and 9 after 1 and 5 min, respect- namic stability, normal maternal
ively, was delivered via the Caesarean coagulation profile and a sufficient
incision. No maternal and neonatal degree of patient cooperation (despite
postoperative
complications
were intoxication) with the anaesthetic
reported. The diagnosis of eclampsia management. Against general anaes-
was ruled out by routine laboratory thesia was the fact that maternal
studies (liver and kidney function tests). mortality rate is many times higher
However, urine and serum toxicology in parturients who undergo abdominal
screening was positive for recent delivery under general anaesthesia as Figure 8
cocaine intake.
The prevalence of recreational drug regional anaesthesia [3].
compared with those who receive
When blood is taken from an arterial
line for analysis, it would be usual to:
attach a 5- or 10-ml syringe to with-
draw heparinised liquid and diluted
blood in the arterial line, remove the
syringe, withdraw blood using another
syringe for analysis and finally re-attach
the first syringe to return the diluted
blood to the body. This practice may
not be acceptable to some Witnesses
because, albeit for a short a period,
blood in the first syringe had lost
contact with the body.
We had occasion to anaesthetise a
baby scheduled for cardiac surgery
whose parents were Jehovah’s Witnes-
ses. We used a simple method to avoid
wasting blood from the first syringe. We
inserted two three-way stopcocks in an
arterial line, attached a 5-ml syringe to
the stopcock distal to the patient and
attached a sampling syringe to the
proximal stopcock (Fig. 8). Liquid in
the arterial line and diluted blood
were withdrawn into the 5-ml syringe,
abuse among young women (including
In conclusion, this case is important
in pregnancy) has increased markedly because it shows the significance of
over the past two decades [1] and individualising anaesthetic management
multiple substance misuse is common. in parturients presenting with diverse
ÔCrackÕ is an almost pure form of clinical manifestations of acute cocaine
cocaine. Pregnancy enhances the car- intake. For other patients with other
diovascular toxicity of cocaine. Acute maternal and ⁄ or fetal expressions of
cocaine intake has been associated acute cocaine intake, other anaesthetic
with obstetric emergencies such as choices might be more appropriate.
placental abruption and fetal distress.
K. M. Kuczkowski
In most cases of placental abruption,
University of California San Diego,
delivery is the treatment of choice.
San Diego, California, USA
The combination of hypertension,
E-mail: kkuczkowski@ucsd.edu
proteinuria and convulsions resulting
from acute cocaine intake may be
mistaken for eclampsia at presenta-
References
1
2
3
Kuczkowski KM. Cocaine abuse in
pregnancy – anesthetic implications.
International Journal of Obstetric Anesthesia
tion; consequently, laboratory studies
liver and kidney function tests) may
(
be the key differential between the
two disorders.
2
002; 11: 204–10.
Birnbach DJ. Anesthesia and maternal
substance abuse. In: Norris MC, ed.
Obstetric Anesthesia. Philadelphia, PA:
Lippincott 1999, 491–9.
The diverse clinical manifestations
of acute cocaine intake combined with
the physiological changes of pregnancy
and the pathophysiology of coexisting
pregnancy-specific disease might result
in life-threatening complications and
significantly impact on the practice of
obstetric anaesthesia. Both regional
and general anaesthesia in the co-
caine-misusing parturient may be asso-
ciated with serious complications [2].
Hawkins JL, Koonin LM, Palmer SK
et al. Anesthesia-related deaths during
obstetric delivery in the United States,
0
.3 ml of blood was withdrawn to the
sampling syringe and diluted blood in
the 5-ml syringe was then returned to
the patient. The operation proceeded
successfully and the baby was discharged
from the hospital without any adverse
effects.
1
2
979–1990. Anesthesiology 1997; 86:
77–84.
When regional anaesthesia is selected, A method of blood conservation
combative behaviour, altered pain per- in Jehovah’s witnesses
ception, cocaine-induced thrombo-
T. Asai
K. Shingu
cytopenia
and
ephedrine-resistant It is essential to make every effort to
Kansai Medical University,
Moriguchi City, Osaka, 570–8507,
Japan
hypotension may be encountered. minimise the loss of blood during
Cardiac arrhythmias, hypertension surgery, particularly in Jehovah’s Wit-
and myocardial ischaemia may be nesses. Although individuals’ beliefs
encountered under general anaesthesia. may differ, some Witnesses believe that
All inhaled anaesthetic agents may it is acceptable to withdraw blood from
produce cardiac arrhythmias and in- the body and return blood as long as it
creased systemic vascular resistance in remains in contact with the body.
E-mail: asait@takii.kmu.ac.jp
K. Fujise
Ishikiri Seiki Hospital,
Higashi-Osaka City, 579–8026,
Japan
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.
Labour-induced sickle cell crisis
in a previously asymptomatic
parturient with sickle cell
disease
continuous epidural infusion of ropiva- patients with sickle cell disease. Patients
)1
caine 0.1% and fentanyl 2 lg.l at a rate with sickle cell disease have an increased
)1
of 12 ml.h
was initiated. Shortly incidence of preterm labour, placental
thereafter, the patient reported complete abruption, placenta praevia and preg-
resolution of her symptoms. She nancy-induced hypertension. It has
Faron et al. described the first sickle cell remained haemodynamically stable and been suggested that sickle cell crises
crisis triggered by induction of labour in comfortable for the remainder of her are more frequent during pregnancy,
a previously asymptomatic primigravida labour. A 2350-g female infant was particularly at term, and that these crises
[
1]. I herein report a similar case (and delivered vaginally (Apgar scores of 8 are most likely due to changes in
the first triggered by the spontaneous and 10 after 1 and 5 min, respectively) clotting factors activities [4]. Effective
onset of labour) documenting the first 3 h after induction of CSEA. The management of labouring patients with
lifetime occurrence of a vaso-occlusive postpartum period was unremarkable.
sickle cell disease ⁄ crisis should include
Sickle cell disease is an autosomal prompt administration of labour anal-
recessive haematological disorder, gesia [5]. Finer et al. reported on a
crisis in a previously asymptomatic
parturient with sickle cell disease.
A 17-year-old, 169-cm, 66-kg, grav- which is caused by the single substitu- patient in active labour with superim-
ida 1, para 0 African American female tion of valine for glutamic acid in the posed sickle cell crisis and theorised that
with sickle cell disease and poor prenatal sixth position of the beta chain of the termination of her crisis may have
care (run away from home, unwanted haemoglobin [2]. When de-oxygen- been the result of improved blood flow
teenage pregnancy) was admitted to the ated, the affected haemoglobin mole- and decreased sludging through the
labour and delivery suite at 37.5 weeks cules polymerise, causing the sickled affected area due to decreased sympa-
gestation in the active phase of labour. shape deformation of the erythrocyte thetic tone from the local anaesthetics
She was agitated, cold and thirsty, and cellular membrane. The sickled erythro- used for her epidural labour analgesia
complained of severe abdominal, back cytes subsequently display diminished [5]. Because of rapid onset of analgesia,
and chest (rib) pain. Although her past ability to traverse the capillary of the CSEA (as proven in this report) may
medical history was significant for sickle the microcirculation, leading to be particularly suitable for labouring
cell disease (haemoglobin SS), the microvascular occlusion of blood flow, patients with symptoms of vaso-occlu-
patient denied any prior painful vaso- tissue hypoxia, end-organ ischaemia sive sickle cell crisis.
occlusive episodes. She was afebrile, had and ⁄ or infarction. In the United States,
In conclusion, I believe that maternal
no known drug allergies and no history sickle cell disease is most commonly peripartum stress (in this case homeless-
of prior anaesthesia. Her admission seen in the African American popula- ness, unwanted teenage pregnancy) in
blood pressure was 135 ⁄ 70 mmHg, tion, with the estimated prevalence of 1 addition to dehydration, hypothermia
)
1
heart rate 74 beat.min and respiratory in 700 African American individuals. In and transient repetitive hypoxia (due to
)
1
rate 22 breath.min . Pulse oximetry patients with sickle cell disease, sickling uterine contractions) all combined to
revealed an arterial blood oxygen sat- occurs at a Pa 2
uration of 95% on room air. Her chest 40 mmHg.
was clear to auscultation. Haemoglobin
O
of approximately play a causative role in triggering the
first lifetime sickle cell crisis in our
A sickle cell crisis typically becomes patient.
)
1
and haematocrit were 9.8 g.dl and evident with abdominal and ⁄ or chest
0.0%, respectively. A peripheral blood pain, fever, tachycardia and haematuria.
K. M. Kuczkowski
3
University of California San Diego,
San Diego, California, USA
E-mail: kkuczkowski@ucsd.edu
smear demonstrated significant sickling Hypoxia, hypothermia, acidosis, dehy-
of red blood cells and a working diag- dration, stress and ⁄ or intercurrent ill-
nosis of sickle cell crisis in a labouring ness are all known precipitants of
parturient was established. Fetal heart sickling, and should be avoided. Ade-
)1
References
rate was 145 beat.min and reactive.
quate hydration to maintain intravascu-
1
Faron G, Corbisier C, Tecco L, Vokaer
A. First sickle cell crisis triggered by
induction of labour in a primigravida.
European Journal of Obstetrics, Gynecology
and Reproductive Biology 2001; 94: 304–6.
Danzer BI, Birnbach DJ, Thys DM.
Anesthesia for the parturient with sickle
cell disease. Journal of Clinical Anesthesia
Oxygen via the facemask was admin- lar volume and ensure optimal tissue
istered, warm blankets were applied and perfusion (preventing systemic acidosis)
the patient was hydrated. When optim- is necessary. Hypothermia should be
ised, she consented to combined spinal avoided, because it produces sickling,
epidural analgesia (CSEA), which was probably as a result of vasoconstriction,
performed in a standard manner with an increased blood viscosity and stasis.
2
3
1
8-guage Tuohy–Schliff epidural needle Parturients with sickle cell crisis should
and a 25-guage Whitacre spinal needle. be well oxygenated, with close monit-
An intrathecal induction dose of labour oring of oxygen saturation [3].
1
996; 8: 598–602.
Tsen LC, Cherayil G. Sickle cell-
induced peripheral neuropathy follow-
ing spinal anesthesia for Cesarean
delivery. Anesthesiology 2001; 95:
analgesia included ropivacaine 2 mg and
The physiological changes of preg-
fentanyl 20 lg. A 20-guage multi-ori- nancy (anaemia, increased oxygen con-
fice epidural catheter was inserted 4 cm sumption, decreased activity and
into the epidural space and after negative hypercoaguable state) may exacerbate
catheter aspiration for CSF and blood, a the medical complications seen in
1
298–9.
1
044
Ó 2003 Blackwell Publishing Ltd

Anaesthesia, 2003, 58, pages 1023–1045
Correspondence
....................................................................................................................................................................................................................
.
4
Howard RJ, Tuck SM, Pearson TC.
Pregnancy in sickle cell disease in the
UK: results of a multicentre survey of
the effect of prophylactic blood trans-
fusion on maternal and fetal outcome.
visited the camp earlier this year. mostly unwilling troops to flush them
Photography is forbidden and cameras out. A carefully tended grave of one of
must be deposited at the Ranger’s hut the rebels lies alongside the path.
before starting the trek. There is a According to the ranger, he died during
command post, radio station (Radio surgery 2 days following a strafing
British Journal of Obstetrics and Gynae- Rebelde), a museum and, of greater attack. Was Che the surgeon or anaes-
cology 1995; 102: 947–51.
interest to me, a thatched field hospital. thetist? (could have been both). Did the
Here, I saw what was left of the patient die of cyclopropane shock? Fur-
anaesthetic machine. The head, moun- ther musings later that evening fuelled
5
Finer P, Blair J, Rowe P. Epidural
analgesia in the management of labor
pain and sickle cell crisis – a case report. ted on a stand, had rotameter knobs for by the heat, generously laced mojitos
Anesthesiology 1988; 68: 799–800.
oxygen, cyclopropane and nitrous and the live music of the original
oxide. It resembled that of the Connell Quintento Rebelde made me wonder
Stratosphere anaesthetic apparatus. (I had whether I had actually twiddled the
carefully studied ÔPhysics for the Anaes- knobs of an anaesthetic machine used by
thetistÕ for my Primary all those many Che, the campus icon of my years in
Was Che an anaesthetist?
Commandancia de la Plata, Fidel Cas- years ago.)
tro’s base of operations during the
Cuban revolution, lies at the end of a ified doctor. He was holed up here with
sweaty hike through misty forest that Fidel and 300 other rebels, when in
covers the hills of Sierra Maestre. I 1958, the dictator Batista sent 10 000
medical school in the early sixties.
Ernesto ÔCheÕ Guevara was a qual-
W. O. Roberts
Ysbyty Gwynedd,
Bangor LL57 2PW, UK
Ó 2003 Blackwell Publishing Ltd
1045