Full text of DOI:10.1046/j.1365-2044.2000.01766-9.x

Anaesthesia, 2000, 55, pages 1127±1143
...............................................................................................................................................................................................................................................
.
Correspondence
A case for co-ordinated
investigation and reporting of
hypersensitivity-type drug
reactions in the UK
scene, allowing rapid decision making (1994±1996) is virtually identical to
as to the nature of the reaction those in 53 consecutive UK reactions
mechanism (anaphylactic, anaphylac- reported by NARCOS [6] in 1994
toid, other). This assay, first used as a (Table 1).
large-scale screening technique in Shef-
A recent enquiry caused us to look at
Despite the introduction of new drugs, field, is now used worldwide. Other the time lapse between anaesthetic
improved monitoring and increased assays such as that for the histamine induction and the onset of clinical
awareness, the incidence of life-threa- metabolite, methyl histamine, further manifestations. General reading suggests
tening anaphylactoid reactions to drugs `fine-tuned' the investigation [3].
that these are immediate, i.e. within a
used in anaesthesia and intensive therapy In the UK, the ready availability of few seconds of drug(s) administration,
is probably little changed from the such assays, coupled to the indication of although studies of the plasma histamine
observations of Macintosh in 1949 [1]. the Association of Anaesthetists Work- release curves in clinical trials [7] show
Prior to the virtual demise of the NHS ing Party Reports [4] of 1990 and 1995 histamine release peaking between 2
Supraregional Assay Services (SAS) that any large-scale hospital laboratory and 5 min. We wondered if time vari-
almost a decade ago, the majority of should be able to investigate anaphy- ation provided clues to mechanism: we
UK reactions were referred to the lactoid reactions, has slowly devalued were aware that dextran manifestations
Supraregional Protein Reference Unit NARCOS to a simple assay service. usually occur 10 min into infusion
(
PRU) based in Sheffield. Its anaesthetic The Unit still gathers the bulk of UK following 20±50 ml infused fluid and
service, initiated in 1975 and known as reactions, but the majority without any that such reactions are IgG antibody
NAARAS, was funded by a group of indication of the patient's problem, mediated. We selected two drugs for
leading pharmaceutical companies and reaction details or management. Much study ± succinylcholine, where reaction
provided a free referral system for anaes- valuable and `cheaply obtained' research is IgE mediated anaphylaxis, and propo-
thetists and others faced with such material is now being lost. Findings are fol, infrequently immune with cardio-
immediate reactions. Following the relegated to the local requirement, and vascular manifestations usually secondary
demise of SAS, the anaesthetic service the wider perspective of combined data to bronchospasm. The data extracted
still continued but was then funded by overlooked.
assay fees. It was then known as
It is still not possible to identify the data in more than 100 reports reduced
NARCOS, in which form it continues patient at risk except in vague general- the numbers to 15 (Table 2).
from 1990 reports are tabulated; missing
to date. Similar centralised services were ities of previous family history and
Although preliminary, this survey
and are available in France, co-ordinated allergy. The necessary use of multiple indicated that immediate bronchospasm
by Laxenaire and Moneret-Vautrin, and drugs for anaesthesia and surgery still (biased to propofol) is unlikely to be
in Australia, co-ordinated by Fisher and provides the bulk of anaphylactoid missed by the anaesthetist, but that the
Baldo. Active dialogue existed between response, and isolating these non-spe- classic IgE-mediated manifestations of
these centres, some research laboratories cific reactions from those of error and of hypotension may be delayed or possibly
(
e.g. Lorenz, Marburg, Salo, Turku) and specific drug response (anaphylaxis) is unobserved for at least 5 min. Five
the pharmaceutical industries. essential for the future care of the minutes on from induction the patient
The availability of a commercial assay, patient involved and a defence in the may be in the anaesthetic room being
plasma tryptase (Pharmacia), to provide increasing tide of litigation.
ventilated and observation of the reac-
simple accurate measures of mast cell The current broad distribution of tion may be delayed, with a disastrous
degranulation based on the work of these mechanisms in France (as reported outcome. Oddly, the distribution for
Schwartz et al. [2], transformed the by Laxenaire [5]) from 1648 patients succinylcholine here is mirrored by
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. Copy should be
prepared in the usual style and format of the Correspondence section. Authors must follow the advice about references and other
matters contained in the Notice to Contributors to Anaesthesia printed at the back of each issue. The degree and diplomas of each
author must be given in a covering letter personally signed by all the authors.
Correspondence presented in any other style or format may be the subject of considerable delay and may be returned to the author for
revision. If the letter comments on a published article in Anaesthesia, please send three copies; otherwise two copies of your letter will suffice.
q 2000 Blackwell Science Ltd
1127

Correspondence
Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
Table 1
analysis of samples from adverse drug New house officers' knowledge
reactors.
of resuscitation, fluid balance
and analgesia
Mechanism
France
UK
J. Watkins
Sheffield S10 3BJ,
UK
In August 1999, I conducted a postal
survey of 242 new house officers in the
first four weeks of their first house job.
Using clinical scenarios, I tested their
knowledge of resuscitation, fluid bal-
ance and analgesia. I received 63 replies
(response rate 26%), of which 53 were
useable. The results are summarised in
Table 3.
Anaphylactic
42%
37%
21%
32%
45%
23%
(
Immune)
Anaphylactoid
Non-immune)
Other
G. Wild
S. Bex
(
A. M. Ward
Northern General Hospital,
Sheffield S5 7YT,
UK
studies of Lorenz [7] infusing low
concentrations of histamine into volun-
teers. Our reactor profiles may thus
reflect both genetic variation in hista-
The majority of respondents (32/53)
had spent just one week on formal
attachment to anaesthesia at medical
school; 9/53 said they had spent no
time in the specialty. For resuscitation,
only 15/53 (28%) said that anaesthetists
had played a major role in teaching. For
fluid balance, the figure was 12/53
References
mine release and variations in receptor 1 Macintosh RR. Deaths under
uptake.
anaesthetics. British Journal of Anaesthesia
There is clearly much to be learned
1949; 21: 107±36.
from the careful study of well-docu- 2 Schwartz LB, Metcalfe DD, Miller JS,
mented cases. Sadly, our own records
deteriorate badly from 1993 for the
reasons outlined. We are aware of
the valuable work carried out by the
Committee on the Safety of Medicines
Earl H, Sullivan T. Tryptase levels as an
indicator of mast cell activation in
systemic anaphylaxis and mastocytosis.
New England Journal of Medicine 1987;
316: 1622±6.
(23%) and for analgesia, 21/53 (40%).
The brevity of a letter barely does
justice to the seriously deficient under-
standing shown by most respondents
(CSM). It has been stated that 3 Watkins J, Wild G. Improved diagnosis regarding these basic skills of peri-
NARCOS could dilute their input
records. This was never the case; the
argument against direct input of clinical
observation by the anaesthetist is that
cause and effect is not obvious without
of anaphylactoid reactions by
measurement of serum tryptase and
urinary methyl histamine. Annales
Francaises d'Anesthesie et de Reanimation
1993; 12: 169±72.
operative care. However, it demon-
strates many of the common avoidable
errors and omissions that vex those of us
occasionally called to `rescue' patients
on the ward.
laboratory analysis, as compared with 4 The Association of Anaesthetists of
The profile of the anaesthetist is
changing, as is the public's expectation
of doctors' competence; it is time we
pressed for greater involvement of
departments of anaesthesia in providing
structured undergraduate training pro-
grammes in peri-operative care.
reports for antibiotics, antidepressants
and other long-term `single' medica-
tions. The original Sheffield PRU
model is similar to that used in France
and Australia in terms of sample analysis
Great Britain and Ireland and the
British Society of Allergy and Clinical
Immunology. Suspected Anaphylactic
Reactions Associated with Anaesthesia,
revised edition. 1995.
and interpretation. However, France 5 Laxenaire MC. Epidemiologie des
relies on co-ordinated analysis from a
chain of centres across the country. This
is probably the way forward in the UK,
with a co-ordinating centre identified to
collate data from all units providing
reactions anaphylactoides
T. Meek
peranesthesiques. Quatrieme enquete
multicentrique. Annales Francaises
d'Anesthesie et de Reanimation 1999; 18:
796±809.
Royal Victoria Infirmary,
Newcastle-upon-Tyne NE1 4LP,
UK
6
7
Watkins J. Adverse reaction to
neuromuscular blockers: frequency,
investigation and epidemiology. Acta
Anaesthesiologica Scandinavica 1994; 38
(Suppl. 102): 6±10.
Pre-anaesthesia assessment
clinics. Beauty in the eye of the
beholder?
Table 2
Time of
onset
Suxameth-
onium
n ˆ 8
Propofol
n ˆ 7
Lorenz W, Doenicke A, Sch oÈ ning B,
It is with interest that I read the corre-
(
min)
Neugebauer E. The role of histamine in spondence [1±3] relating to my recent
adverse reactions to intravenous agents. letter about pre-anaesthetic assessment
In: Thornton JA, ed. Adverse Reactions clinics or PAACs [4]. It has obviously
to Anaesthetic Drugs; Monographs in
Anaesthesiology; 8: Amsterdam:
Elsevier/North Holland Biomedical
Press, 1981: 169±238.
Immediate (, 30 s)
1
3
1
1
2
1
5
1
0
0
1
stimulated a great deal of thought. Of
particular interest were the views of Dr
J. R. Davies and Dr D. B. Baines, which
I feel warrant further discussion.
1
2
5
±2
±3
1128
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Table 3 Summary of results from answers to questionnaire. (n ˆ number of respondents able to attempt scenario; f ˆ frequency of correct individual criteria.)
Scenario (style of answer in parentheses)
Summary of criteria assessed
n
Individual criteria assessed
f
1. Treatment of ventricular fibrillation (free text)
Adherence to major points of
current Advanced Life Support
guidelines
52
Assess rhythm
Check pulse
Defibrillate; 200 J x 2, thereafter 360 J31
Cardiopulmonary resuscitation;
24
17
31
1
min or 10 cycles
28
10
2
Adrenaline; 1 mg i.v. every 3 min
All five of the above
2
. Description of use of self-ventilating bag and
Inclusion of major elements of procedure
Fluid volume and electrolytes prescribed
51
52
Appropriate head position
Manoeuvre to open airway
Use of airway adjunct
Connect oxygen
Two-person manoeuvre
12
19
6
24
32
24
9
±
±
±
mask device during cardiopulmonary resuscitation
free text)
(
1:5 breath:compression ratio
Check for evidence of ventilation
Volume, range (median): 500±4500 (3000) ml.24 h
Sodium, range (median): 0 ± 450 (150) mmol.24 h
Potassium, range (median): 0 ± 120 (40) mmol.24 h
2
1
3. Prescription of first 24 h maintenance fluid
2
1
following hemicolectomy in otherwise healthy
2
1
6
4
0-year old male (blank fluid prescription chart)
. Simple postoperative oliguria following open
Identification of:
a. diagnosis
cholecystectomy in otherwise healthy 30-year old
female. Scenario strongly suggestive of
hypovolaemia (free text)
51
51
Correct
Incorrect
Tachycardia
Hypotension
49
b. correct supportive signs and symptoms
24
32
7
Low JVP
Dry mucous membranes
Decreased skin turgor
Decreased peripheral perfusion
Thirst
23
33
16
17
8
Sunken eyes
c. correct treatment themes within answer
51
Appropriate fluid challenge
Assess response
Repeat and reassess
Alert help if no improvement
Consider/exclude surgical cause
Prescriptions matching criteria
19
15
2
2
2
5
1
. Prescription of postoperative analgesia in fit
8-year old male, following internal fixation
Prescription containing regular non-
steroidal anti-inflammatory drug and/or
paracetamol with opiate bolus
available for breakthrough pain.
±
43
53
3
of ankle fracture (blank drug prescription chart)
6. Are you happy to administer intravenous
Yes
No
18
35
morphine in a ward setting? (tick boxes)
Reasons indicated for answering `no' (nˆ35):
Risk of respiratory depression
Risk of nausea and vomiting
Don't know dose
No experience
Never been taught
Shouldn't be administered on ward
Job of more senior doctor
Unable to monitor patient on ward
13
8
12
28
19
2
1
5

Correspondence
Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
Dr Davies states that while PAACs Centre to that in which Dr Baines Hospital and School on the advance-
may be a valuable adjunct to anaesthetic works) involved a major input from ment of Academic Anaesthesia. Our
practice in the UK, the cost of such a Consultants who were far from `semi first paper covered the period from the
system may not comply with the cost- retired' and, in complete contrast to Dr introduction of chloroform to the
effective nature of the NHS. (A senti- Baines' experience, it allowed me to outbreak of the First World War and
ment shared by many of us in relation to give more in-depth explanations of pre- was presented at the History of Anaes-
a variety of treatments and practices medication, induction techniques and thesia (HAS) meeting in Cambridge in
within the NHS!) In his argument he potential postoperative analgesic options/ October 1999 [1]. It is perhaps unfor-
compares the pay structure of doctors in requirements. Indeed, compared with tunate that we do not seem to have a
Australia and the UK, citing increased previous experiences, it reduced the dental surgeon among the members of
payments for `out of hours work' as one `sausage factory' concept of getting the HAS.
reason for the possible use of daytime patients through the system. As an
The story is fascinating. Within days
clinics in place of evening `premeds'. anaesthetist now re-ensconced in the of James Y. Simpson's description of the
This is not entirely true as it makes UK, I therefore feel I can draw upon anaesthetic properties of chloroform,
the assumption that all hospital doctors my experience of the Australian peri- his friend and neighbour, Francis
in the Australian system are paid in such operative system in a positive fashion.
a fashion. Trainees (SHO and Specialist
Imlach, a distinguished dental surgeon,
Thus, given our polarised experi- gave chloroform to one of his appren-
Registrar equivalents) and self-employed ences of the PAAC, is it perhaps time tices for the removal of a tooth. Imlach
Consultants or VMOs (Visiting Medical for further appraisal of the effectiveness incidentally was the first dental surgeon
Officers) are paid higher rates for `out of and problems of `the peri-operative to be elected President of the Royal
hours' work; however, Staff Specialists system' rather than relying solely on College of Surgeons of Edinburgh. Sub-
(an approximate equivalent of full/maxi- anecdote from people such as Dr Baines sequently, he and his contemporary
mum part-time NHS Consultants) and and myself?
Clinical Fellows receive fixed salaries.
John Smith became accomplished anaes-
thetists, as well as distinguished dental
surgeons.
J. F. Cosgrove
Freeman Hospital,
The PAAC of which I have experience
was staffed by Clinical Fellows and Staff
Specialists, a situation similar to that
which may arise in the NHS if such
clinics became commonplace. In isola-
tion it therefore may not be cost-
effective in terms of salaries, although
Kerridge et al. [5] have demonstrated
the potential for overall cost-effectiveness
in the peri-operative process in terms of
reduced length of stay, decreased can-
cellations and reduced non-attendance.
Managers may yet see the funding of
medical staff for PAACs within the
In 1860, John Smith, with the
assistance of Francis Imlach and other
colleagues, set up the Edinburgh Dental
Dispensary, which with the passing of
the Dentists Act, 1878 [2], became the
Edinburgh Incorporated Dental Hospi-
tal and School. From its inception, the
discipline of anaesthesia was encour-
aged. During the first decade, two
chloroformists were appointed and a
system of training was introduced which
gradually became more formalised, first
with demonstrations and tutorials, fol-
Newcastle-upon-Tyne NE7 7DN,
UK
References
1
Hocking G, Shaikh L. Anaesthetic pre-
assessment clinics to identify patients at
risk. Anaesthesia 2000; 55: 812.
Davies JR. Pre-anaesthesia assessment
clinics. Anaesthesia 2000; 55: 812±13.
Baines DB. Pre-anaesthesia assessment
clinics. Anaesthesia 2000; 55: 813.
2
3
NHS as a worthwhile cost-effective 4 Cosgrove JF. Anaesthetic preassessment lowed later by a more academic lecture
and quality of care exercise!
Other points of interest with respect 5 Kerridge R, Lee A, Latchford E,
clinics. Anaesthesia 2000; 55: 405±6.
programme. Thereafter, various anaes-
thetic techniques were introduced and
developed, new apparatus was designed
to exploit physical principles, and phar-
macological and physiological responses
to PAACs were made by Dr Baines
giving balance' to my previous corre-
Beehan SJ, Hillman KM. The
perioperative system. A new approach
to managing elective surgery.
`
spondence [4]. He/she states that whilst
PAACs are cost-effective, their overall
benefit remains unproven, particularly
with respect to them `enhancing our
role' and `improving training'. I cer-
Anaesthesia and Intensive Care 1995; 23: began to be studied. Thus the Dental
591±6.
Hospital developed as a centre of anaes-
thetic teaching and research before the
University teaching hospital. The Royal
Infirmary had even appointed an anaes-
thetist. Accordingly, when William Guy
tainly accept that my views on Austra- Gone but not forgotten!
lian PAACs are based entirely on my
own experience as a foreign visitor and Your correspondents (Brett & Wraith. was appointed Dean in 1899, he had
have not been subject to any controls of Anaesthesia 2000; 55: 593) have little to little difficulty in persuading his collea-
a `double-blinded randomised nature'; fear; the contribution of Dentistry to gues that, in future, anaesthetics should
however, I find it regrettable that he/she the development of Anaesthesia has not only be administered in the hospital
feels that they have been `foisted on us been forgotten. As it happens, some two under the direction or in the presence
by the minority'. The system I encoun- years ago we began to explore the of a qualified medical practitioner. It
tered (albeit in a different Regional influence of the Edinburgh Dental should be added that virtually all the
1130
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Anaesthesia, 2000, 55, pages 1127±1143
Correspondence
.
...............................................................................................................................................................................................................................................
staff were doubly qualified, in medicine
as well as in dentistry; in addition, a
substantial number held higher qualifi-
cations in surgery.
It is surely significant that 50 years
later at the end of the forties when we
ourselves were in anaesthetic training
posts in Edinburgh, three of the con-
sultant anaesthetists responsible for our
training were also qualified in dentistry,
two of whom held simultaneous con-
sultant appointments as dental surgeons.
A. H. B. Masson
Honorary Archivist,
Royal College of Surgeons of
Edinburgh and formerly consultant
anaesthetist,
Royal Infirmary of Edinburgh,
Edinburgh EH12 5YT, UK
Figure 1
J. P. Payne
Emeritus Professor of Anaesthesia,
University of London,
London SW19 4AP, UK
silver Negus tube still in position (Figs 1 a size 6.0 armoured cuffed tracheal tube
and 2). This simple manoeuvre pro- without the patient coughing. Surgery
duced an excellent airway seal and proceeded uneventfully.
anaesthesia was induced with 100 mg of
A silver Negus tracheostomy tube
References
fentanyl and 150 mg of propofol. Prior cannot be connected to an anaesthetic
to the administration of muscle relaxants breathing circuit via the standard 15-
it was confirmed that the patient could mm connector. As the presence of the
easily be ventilated through the LMA tracheal stenosis would have precluded
used in this fashion. Muscle relaxants any airway instrumentation above it, the
were administered, the trachea sprayed options for ventilating this patient on
with 120 mg of lidocaine and the induction of anaesthesia would have
tracheostomy tube easily replaced with been the replacement of the Negus tube
1
2
Masson AHB, Payne JP. The influence
of the Edinburgh Dental Hospital and
School on the advancement of
academic anaesthesia. HAS Proceedings
2
000; in press.
Anon. Dentists Act. An Act to amend the
Law relating to Dental Practitioners. 1878.
Ventilation through a metal
tracheostomy tube
A 29-year-old female was scheduled to
have a laryngotracheoplasty for severe
tracheal stenosis thought to be second-
ary to prolonged tracheal intubation
several years previously for severe
asthma. Her past medical history was
otherwise unremarkable. She had a
silver Negus metal tracheostomy tube
(28 French gauge) in situ. It was felt that
any instrumentation of her airway could
potentially precipitate coughing and
bronchospasm. Appropriate monitoring
consisting of ECG, non-invasive blood
pressure and oxygen saturation was
instituted. The patient was pre-oxyge-
nated by placing the bevel of a size 3
laryngeal mask airway (LMA) firmly
over the tracheostomy site with the Figure 2
q 2000 Blackwell Science Ltd
1131

Correspondence
Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
either with a Portex tracheostomy tube 1 The authors rightly point out that and their valuable comments. Unlike
or a tracheal tube prior to the induction this technique requires an experienced the authors, we perform TLT with a
of anaesthesia. However, we felt that team. This is essential and ideally should team of two anaesthesiologists, one of
any difficulties encountered in inserting consist of three anaesthetists, one of whom performs the tracheostomy, and
a different airway whilst the patient was whom is concerned solely with main- the second colleague performs bron-
awake would have led to unnecessary taining the airway and the patient's choscopy and insertion of the small-
instrumentation and trauma to the oxygenation.
bore ventilation tube. An ICU nurse
airway, coughing and undue distress to 2 The partial occlusion of the tracheal trained in TLT is solely responsible for
the patient. Induction of anaesthesia lumen by the bronchoscope during stabilising the ventilation tube to mini-
without prior knowledge that ventila- insertion of the guide-wire may lead mise the risk of airway loss by accidental
tion could be accomplished in an to high inflation pressures and we find
atraumatic fashion was deemed unsafe. that switching to manual ventilation at
Another option could have been the use this point results in more effective
of a paediatric facemask employed in a oxygenation.
similar fashion to the LMA [1]. How- 3 The thin-walled tracheal tube allows
ever, it is often difficult to establish a ventilation of the lungs while the
tight seal over the stoma with this tracheostomy is being performed, but
technique, and as an excellent seal was it is essential that this tube is correctly
accomplished with the LMA this option positioned and not allowed to move as
was not explored further. We are aware unrecognised endobronchial intubation
of one other report in the literature is potentially life threatening in the
describing the use of the laryngeal mask high-risk patient.
extubation.
We use volume-controlled ventila-
tion during TLT to ensure a given tidal
volume regardless of pressure. A high
inflation pressure is generated by the
increased resistance of the tube's small
diameter, but has been demonstrated
not to affect the lungs [A. Pesenti, per-
sonal communication]. Correct position
of the small-bore ventilation tube is
confirmed by auscultation of the lungs.
Once endobronchial intubation has
been ruled out, the tube's position is
maintained manually as described above.
The concept of maintaining the venti-
lation tube in place during cannula
placement and rotation has also been
advocated by Fantoni himself [2], but in
the majority of reports on TLT the tube
has been removed before cannula rota-
tion was attempted. On the other hand,
there are no reports of tracheal injury
during cannula rotation with the tube
in place. Based on the recent literature
and personal communication, both tech-
niques seem to be equally safe.
airway to ventilate a patient through a
tracheostomy orifice [2].
4
Our practice is not to remove the
ventilating tube until the tracheostomy
tube has been rotated and secured.
While we agree that damage to the
trachea is theoretically possible, we have
not encountered any problems, and
having observed the rapid development
of tracheal oedema following removal of
the tracheal tube, have our doubts about
the advisability of relying on emergency
oral re-intubation in unstable hypoxic
patients should difficulties arise. We
concede, however, that the majority of
our patients are undergoing tracheost-
omy at a later stage than those described
in the article (10±14 vs. 5±6 days) and
that this may present us with more
difficult operating conditions.
M. Protopapas
C. N. Ferguson
Royal National Throat Nose & Ear
Hospital,
London WC1X 8DA, UK
References
1
2
Raymond J, Hardy JF. Oxygenation par
tracheostomie. Canadian Journal of
Anaesthesia 1990; 37: 274±5.
Morita Y, Takenoshita M. Laryngeal
Mask Airway fitted over a tracheostomy
orifice: a means to ventilate a
We have not yet encountered any
problems with oral re-intubation should
placement of the TLT cannula fail. This
also held true in patients who had
been intubated with a tracheal tube for
an extended period of time before
tracheostomy. Nonetheless, we feel that
early percutaneous tracheostomy should
be considered whenever possible,
because several studies have shown that
the critical period for the development
of laryngotracheal lesions caused by the
tracheal tube is between the 7th and
11th day of intubation and possibly
earlier [3±5].
tracheostomised patient during
induction of anaesthesia. Anesthesiology
In conclusion, we feel that tran-
slaryngeal tracheostomy is a valuable
technique but that the potential diffi-
culties should not be underestimated.
1
998; 89: 1295.
Translaryngeal tracheostomy in
the high-risk patient
K. R. Milligan
J. C. McCollum
Belfast City Hospital,
Belfast BT9 7ASB,
UK
We read with interest the article
(Byhahn et al. Anaesthesia 2000; 55:
6
76±82) describing the use of the
Fantoni tracheostomy technique in
high-risk patients. We have used this
technique in similar situations and fully A reply
In conclusion, we agree with Drs
endorse their view that this is a suitable We would like to thank Drs Milligan Milligan and McCollum that TLT
technique for the high-risk patient. We and McCollum for their response to our requires an experienced team especially
would, however, wish to make a few article about translaryngeal tracheos- in patients at high risk of adverse
comments.
tomy (TLT) in high-risk patients [1] sequelae during tracheostomy.
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Anaesthesia, 2000, 55, pages 1127±1143
Correspondence
.
...............................................................................................................................................................................................................................................
C. Byhahn
V. Lischke
the appropriate time to use a Laryngeal power. The surgeon briefly became the
Mask Airway [3]; and so on. only patient monitor available by virtue
K. Westphal
J.W. Goethe-University Hospital
Center,
Given the rarity of failed intubation of his direct visualisation of the carotid
in obstetrics (0.3%) [4], it would seem artery, all other parts of the patient
important that all the information on being hidden under drapes.
D-60590 Frankfurt,
Germany
every failed intubation across the coun-
Within minutes a portable Pro-Pak
try should be obtained. Only when a monitor was obtained which had ECG,
large database has been obtained, pulse oximetry and invasive pressure
including the techniques used and the monitoring. Capnography and agent
problems that result, do we have any monitoring were still unavailable, as
chance of discovering the relative risks were proper suction and surgical dia-
of the different approaches. Only then thermy. The power cut was affecting the
References
Byhahn C, Lischke V. Westphal K.
Translaryngeal tracheostomy in highly
1
2
3
4
5
unstable patients. Anaesthesia 2000; 55: could we have evidence-based guide- whole hospital and there was specula-
78±82. lines. Might this be a role for the tion about its cause and how long it
6
Fantoni A, Ripamonti D. A non-
derivative, non-surgical tracheostomy:
the translaryngeal method. Intensive
Care Medicine 1997; 23: 386±92.
Whited BE. A prospective study of
laryngotracheal sequelae in long-term
intubation. Laryngoscope 1984; 94:
Obstetric Anaesthetists Association?
would last. The battery-operated moni-
tor and lighting had an unknown life-
span as had the supply of compressed air
driving the ventilator. A period of about
20 min had now passed and it was
decided the only option available was to
abandon the procedure and wake the
R. H. James
Leicester Royal Infirmary,
Leicester LE1 5WW, UK
References
3
Bishop MJ. Mechanisms of
67±77.
1 Hewett E, Livingstone P. Management patient up. The patient was recovered in
of failed endotracheal intubation at
caesarean section. Anaesthesia and
Intensive Care 1990; 18: 330±5.
the Intensive Care Unit, which having
natural lighting was far preferable to the
Recovery Unit, which had no light at
laryngotracheal injury following
prolonged intubation. Chest 1989; 6:
1
35±6.
2 Thwaites AJ, Rice CP, Smith I. Rapid all. The power was eventually restored
Bishop MJ, Hibbard AJ, Fink BR,
Vogel AM, Weymuller EA. Laryngeal
injury in a dog model of prolonged
endotracheal intubation. Anesthesiology
sequence induction: a questionnaire
survey of its routine conduct and
continued management during a failed theatre the following morning where
after about 30 min.
The patient returned to the operating
intubation. Anaesthesia 1999; 54:
376±81.
anaesthesia and surgery were carried out
uneventfully.
The power failure was due to the
1
985; 62: 770±3.
3
4
Benumof JL. Laryngeal mask airway
and the ASA difficult airway algorithm. following sequence of events: subcon-
Anesthesiology 1996; 84: 686±99.
Difficult intubation
tractors working on the construction
of a new building drove a steel pile
experience in a teaching maternity unit. through the hospital's main 11-kV
Lyons G. Failed intubation. Six years
It was interesting to read the large study
of failed intubation (Barnardo & Jenkins.
Anaesthesia 2000; 55: 690±4). However,
I note that in the discussion they criti-
cised the use of a second dose of Complete power failure
succinylcholine and hand ventilation
Anaesthesia 1985; 40: 759±62.
incoming power cables. Fortunately,
there were no casualties but a black
out of the entire hospital site and the
immediately surrounding area followed.
Both the standby generators failed to
using relaxants. Although their opinions A 79-year-old man was scheduled for run, resulting in a failure of the essential
are widespread, they are totally contrary elective carotid end-arterectomy during power supply for a period of time.
to those of Hewett and Livingstone [1]. a routine afternoon vascular list. Anaes-
Initial investigation into the generator
In an age of `Evidence Based Med- thesia and surgery proceeded without failure revealed that one generator did
icine' it is worrying that so many aspects incident until just as the surgeon was not start at all, and the other started,
of the bail out drills represent only about to incise the carotid, there was but quickly tripped out on overload.
personal conviction [2]. These include a complete power failure. Initially, it Further investigation revealed a project
the wisdom of head down tilt; the use of was thought the emergency generator team design co-ordination issue, whereby
the left lateral position; when and when would take over after a brief pause but an automatic generator changeover was
not to continue cricoid pressure; the use this did not happen. The operating enabled without the installation of any
of a repeat dose of succinylcholine, theatre was completely dark apart from of the planned load shedding. Hence,
permitting a second (or third) attempt at the operating light, which had a back- the failure of one generator would result
intubation; the safety of continuing up battery. The patient was still being in overloading the other generator. The
volatile anaesthesia with either sponta- ventilated by the bag-in-bottle com- controls were reconfigured to prevent
neous respiration intermittent positive pressed-air-driven ventilator. The Datex the automatic changeover of generators
pressure or ventilation on a facemask; monitor no longer functioned without as an interim measure until phase 2
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Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
of the energy centre redevelopment
and the associated load shedding was
commissioned.
Repeated testing of the generators
off line' failed to reproduce the original
`
failure. `Black start' testing (where by
the main 11-kV supply is turned off,
simulating a `real' power failure) finally
allowed the failure to be traced to a
faulty component in the new generator
control panel. This was replaced, and
a third black start was performed
satisfactorily.
This event highlights the fact that
despite recent extensive planning and
protocols to protect against the year
2
000 bug, we cannot always predict
when disaster may strike but have to
deal with it as best we can. In the suite
of 11 operating theatres, many were
between cases or using regional techni-
ques, which minimised disruption and,
thankfully, this rare and potentially
disastrous mishap did not result in
harm to any patient.
Figure 3
enriched with oxygen, I would suggest flow. Perhaps it represents the answers to
that continuous flow, independent of Dr Fenton's original questions.
back-pressure, has genuine advantages.
J. A. Russell
The ability to use an accurate, high-
Fremantle Hospital,
resistance, vaporiser cannot be dismissed.
Fremantle 6160,
J. C. Tye
D. Chamley
Middlemore Hospital,
Otahuhu,
Even if we were to commit ourselves to
Western Australia
total intravenous anaesthesia, a Mapleson
type rebreathing system with collapsible
Auckland 6,
New Zealand
reservoir bag to give a feel for the state
of the patient's lungs would probably be
worth preserving. Continuous flow may
An unusual case of
gastro-oesophageal reflux'
`
fail to justify itself in the third world We wish to report a case of rupture of a
setting, and I have every respect for nasogastric feeding tube in vivo. The tube
those who cope in its absence, but I in question was a 8 gauge, 110-cm-
cannot see anaesthetists in affluent length Flocare fine-bore polyurethane
countries electing to use self-inflating nasogastric tube (Nutricia Ltd).
Continuous flow vs. draw-over
apparatus
w
I welcome the recent contributions by
Drs Fenton and Lunn suggesting that
bags and draw-over vaporisers.
Briefly, a 71-year-old woman had
It is hardly surprising that the use of been on intensive care for several weeks
room air be considered synonymous with complications of atypical Guillain
their experience in third world and
military anaesthesia has useful lessons for
the rest of us (Fenton. Anaesthesia 1999; with draw-over anaesthesia, as no appa-
Barr e Syndrome. She had a surgical
tracheostomv performed on day 8 with
no problems. During her admission,
nasogastric feed had been noticed
regurgitating around her tracheostomy
5
4: 1111; Lunn. Anaesthesia 2000; 55: ratus has ever been available which can
4
02). In particular, they advocate the deliver oxygen from 21% to 100% at a
use of draw-over anaesthesia for the continuous flow-rate that is independent
growing number of anaesthetists who of backpressure. However, I designed a
regard nitrous oxide as obsolete, and device to address this issue. It was built site and several manoeuvres had been
imply that perhaps the increasingly by Penlon Ltd, Abingdon, UK, and tried to stop this including motility
complex Boyle's machine is starting further developed in the Medical Physics agents, reducing the feed rate, and
to look over-specified. My own view Department of the Royal Perth Hospi- finally replacing the nasogastric tube.
is that we should try to distinguish tal, Western Australia, and uses a double At that time the tube was not specifi-
between two separate but related con- bellows arrangement to entrain room air cally examined, but no obvious defect
cepts, namely the use of room air as and deliver it to the patient via a was reported.
opposed to pressurised air, and the use Mapleson type breathing circuit (see
On day 24, further nasogastric feed
of draw-over as opposed to continuous Fig. 3). The two bellows alternate in was noted around the tracheostomy site.
flow of this air. While it is difficult to their action during spontaneous respira- The ITU SHO passed a new fine-bore
question the logic of using room air tion in order to generate continuous nasogastric tube on day 26 and its
1134
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Anaesthesia, 2000, 55, pages 1127±1143
Correspondence
.
...............................................................................................................................................................................................................................................
an ITU SpR could not rupture the
tube.
We could find no reports of this in
published literature. The manufacturer
has heard of one possible case, but has
no specific details. Since the manufac-
turer states that tubes can be safely used
for up to 6 weeks, we assume that
either the tube (or tubes, which may
have come from the same batch) was
defective, or that one of the drugs
passed nasogastrically allowed a block-
age to occur as well as corroding the
polyurethane. Following this, the 2-ml
syringe used caused the tube to
rupture.
D. Carradice
K. Alagesan
I. Moppett
City Hospital,
Nottingham NG5 1PB,
UK
Figure 4
position was satisfactory on chest X-ray. were omeprazole suspension, liquid
Feeding recommenced without prob- cisapride and temazepam, and soluble
lems until day 38. At this time, feed was paracetamol. None of these is specifi- A reply
again pooling in the pharynx but the cally known to cause nasogastric tube Having read with same concern Dr
patient tolerated oral fluids without blockage or erosion. A 2-ml syringe Carradice's case report, I should like to
regurgitation.
The nasogastric tube was removed the tube on day 37 (manufacturer
and found to be ruptured at two sites. recommend a syringe no smaller than the tracheostomy tube at the time the
Figs 4±6). Our assumption is that this 30 ml). However, testing a new tube first nasogastric tube was placed could
with soda water was used to unblock take the opportunity to comment.
The cause of regurgitation around
(
was due to flushing of the tube after with both water and neat Coca-Cola have been caused by a number of
blockage by nasogastric drugs on two using a variety of syringes from 1 to factors: tube malposition, patient posi-
separate occasions. The drugs given 10 ml and maximal force exerted by tion, delayed gastric emptying or severe
gastro-oesphageal reflux. It would not
have been caused by the Flocare feeding
tube, which as Dr Carradice noted, had
no signs of defect.
Tube occlusion in all fine-bore naso-
gastric tubes is known to be a recog-
nised problem, occurring in 6±10% of
cases [1]. The common causes of these
occlusions include failure routinely to
flush the tube [1], the effect of medica-
tion and gastric juices on enteral feed
causing protein precipitation [2, 3]
crushed medication particles [1, 4],
liquid medication with a pH of 5 or
less (causing changes in feed consis-
tency), viscosity and particle size of the
formulation [5±7].
Care must be taken whilst attempting
to remove tube occlusions to prevent
tube rupture. Tube rupture may occur
when a pressure of more than 40 psi is
applied by an infusion pump or syringe
Figure 5
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Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
2
3
Babb RR. Cimetidine in preventing or
treating acute upper gastro-intestinal
haemorrhage. Western Journal of Medicine
1984; 140: 478±82.
Powell KS et al. Aspirating gastric
residuals causes occlusion of small bore
feeding tubes. Journal of Parenteral and
Enteral Nutrition 1993; 17: 243±6.
Smith A. Inside story. Nursing Times
4
5
1997; 93: 65±8.
Altman V, Cutie AJ. Compatibility of
enteral products with commonly
employed drug additives. Nutrition
Support Services 1984; 4: 8±17.
6
7
8
Gora ML, Tscharipel MM, Visconti
DA. Considerations of drug therapy in
patients receiving enteral nutrition.
NCP 1989; 4: 105±10.
Marcuard SP, Finley JL, Macdonald
KG. Large-bore feeding tube occlusion
by yeast colonisation. JPEN 1993; 17:
Figure 6
187±90.
[8]. It is for this reason that Nutricia as have not been any similar reports for
Lord. LM. Enteral access devices.
Nursing Clinics of North America 1997;
the manufacturer of Flocare tubes does several years, it is unlikely that a tube or
not recommend the use of syringes batch defect was to blame for this
which are smaller than 30 ml. Using a incident.
3
2: 700.
2
-ml syringe to unblock a tube could
J. Knowles
cause the rupture of the tube. Tests
performed by Nutricia Medical Devices
on Flocare Nasogastric tubes, sub-
merged in artificial stomach fluid at
Pressure for success
Nutricia Ltd,
Trowbridge BA14 0XQ,
UK
The movement of critically ill patients,
both within and between hospitals, is
a fairly common event in British
intensive care [1], and is fraught with
potential hazards. The risk of misad-
3
7 8C for several weeks and then
pressurised using a small 10-ml syringe,
showed the same type of rupture.
References
Unfortunately, there were no batch 1 Marcuard SP, et al. Cleaning obstructed venture during transit is proportional
details available from the hospital for
this particular tube, but as there
feeding tubes. Journal of Parenteral and
Enteral Nutrition 1989; 13: 81±3.
to the number of tubes connected to
the patient (intravenous lines, chest
tubes, drains, urinary catheter, etc.),
which is related to the severity of the
patient's condition. These tubes are
there for a good reason, and most
cannot be removed or disconnected
prior to transfer; but those that can,
should be. Some of the most annoying
`
tubes' are those that connect the
pressurised bags of heparinised saline
to the arterial and venous pressure
transducers. The pressure bags are
bulky, frequently lose their pressure
in transit, and have a tendency to
entrain air from the drip chamber
when they are laid flat, which is
almost inevitable at some point in
the process. This is particularly true
during
long-distance
aeromedical
transfers, when there are the additional
problems of not having anywhere to
Figure 7
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Anaesthesia, 2000, 55, pages 1127±1143
Correspondence
.
...............................................................................................................................................................................................................................................
Figure 8
hang them in the confined space of a joined the transducer unit, and is (and therefore the pressure decay) is
small commercial jet aircraft and the then loaded with 10 ml of heparinised likely to be less when connected to an
effect of changes in cabin pressure on saline from a second syringe.
the air-filled pressurisation devices.
arterial line because of the backpressure
Four of these devices were con- effect of the patient's blood pressure. In
These problems can be avoided by structed and connected to a commonly transducers connected to the pulmonary
replacing the bag of heparinised saline, used pressure transducer system (Medex artery or central veins, the pressure loss
pressure bag and giving set with a Medical Inc.), and the pressure gener- is similar to that shown. In either case,
three-way tap and the device shown ated measured (Hewlett Packard). All the system will generate at least
in Figs 7 and 8. The flush device is a four generated more than 350 mmHg 180 mmHg for at least 3 h, and can be
10-ml syringe which has had the for between 45 and 75 min (above the easily topped up with more heparinised
plunger covered with two fingers cut upper limit of measurement for saline via the three-way tap. If this
from a size 8 surgical glove and taped the monitors used), and then generated system had been in use by Scott and
to the barrel of the syringe. The first the pressure/time profile shown in Fig. 9 colleagues [2], they would have had the
finger should be approximately 4 cm (error bars indicate one standard devia- additional benefit of completely pre-
long, the second 5 or 6 cm long. tion). At the end of 3 h of measure- venting the problem they described.
Whilst empty, the syringe is fitted ment, each of the syringes had delivered
I. Mackenzie
John Radcliffe Hospital,
Oxford OX3 9DU, UK
firmly to the three-way tap sited between 5 and 7 ml of fluid. In clinical
where the giving set would have use, the volume loss from the system
References
1
2
Mackenzie PA, Smith EA, Wallace
PGM. Transfer of adults between
intensive care units in the United
Kingdom: a postal survey. British
Medical Journal 1997; 314: 1455±6.
Scott J, Lemmon S, Gr uÈ ning T.
Accidental intra-arterial injection via
the venous limb of a dual pressure
transducer system. Anaesthesia 2000; 55:
724.
Prediction of degree of
hypomagnesaemia during
general anaesthesia
Peri-operative infusion of sodium
lactate solution can reduce serum
Figure 9
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Correspondence
Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
Toyama Medical and Pharmaceutical
University School of Medicine,
Toyama 930±0194,
Japan.
E-mail: koki@ms.toyama-mpu.ac.jp
References
1
2
3
Sanchez-Capuchino A, McConachie I.
Peri-operative effect of major surgery
on serum magnesium. Anaesthesia 1994;
49: 912±4.
Iseri LT, Freed J, Bures AR.
Magnesium deficiency and cardiac
disorders. American Journal of Medicine
1975; 58: 837±45.
Trem eÁ r MR, Schneider J, Marti RA,
Rifat K. Role of magnesium sulfate in
postoperative analgesia. Anesthesiology
Figure 10 Serum magnesium ion concentration Mg (% of control) and the water
balance per body weight. The straight line was satisfactorily fitted by the equation:
py aˆtie n2 ts .0 .44x 1 96.8, r ˆ 0.79 (n ˆ 126). The data points were obtained from 20
1996; 84: 340±7.
Combined emergency
Caesarean section and
intracerebral aneurysm clipping
magnesium ion concentration (Mg) [1]. magnesium determinations were per-
Hypomagnesaemia could induce cardiac formed by an electrolyte analyser
arrhythmia [2] and lower the threshold (CR-8; NOVA biomedical, Waltham,
for nociceptive reaction via modulation MA, USA). Results were expressed as
of the N-methyl-d-asparatate (NMDA) mean (SD). The analysis of variance
receptor [3]. In order to predict the (anova) was used for statistical
degree of hypomagnesaemia during analysis and p , 0.05 was considered
clinical anaesthesia, we have investigated significant.
Management of cerebral aneurysm
clipping with acute subarachnoid hae-
morrhage during pregnancy involves
medical issues and poses an interesting
challenge to anaesthesiologists, obste-
tricians and neurosurgeons [1±3]. We
present a case of acute subarachnoid
bleeding in a pregnant patient in
whom emergency Caesarean section
was performed followed by craniot-
omy and clip obliteration of the
aneurysm.
A 38-year-old patient at 36 weeks
gestation experienced severe headache
with loss of consciousness induced by
Hunt and Hess Grade IV subarachnoid
haemorrhage. Following emergency
intubation with methohexitone and
succinylcholine, anaesthesia was main-
tained with fentanyl, midazolam and
atracurium. The fetal heart rate was
monitored by Doppler sonography in
addition to monitoring of maternal
heart rate, invasive arterial blood pres-
sure, end-expiratory CO2 and urine
output. Computed tomography and
intra-arterial digital subtraction angio-
graphy revealed a large ruptured aneu-
rysm of the right internal carotid artery
(Figs 11 and 12). Superselective angio-
graphy was performed under moderate
the relations between amount of fluid
infusion and magnesium.
The intravenous administration of
magnesium-free acetated Ringer solu-
tion reduced Mg. Before fluid infu-
After obtaining approval from our
research ethical committee and infor-
med consent, we studied 20 patients
21
sion Mg was 0.51 (0.03) mmol.l
n ˆ 20), and 1500 and 3000 ml of
fluid administration significantly
reduced Mg to 0.45 (0.02) (n ˆ 20)
(
(American Society of Anesthesiologists
physical status I or II, 16±84 years old)
undergoing elective surgery under
general anaesthesia (1.0±1.5% isoflur-
ane and 60% nitrous oxide in oxygen,
and 100±300 mg of fentanyl) at the
Toyama Medical and Pharmaceutical
University Hospital. Patients with renal
impairment or receiving diuretics or
steroid treatment were not studied. All
patients received intravenous infusion
of magnesium-free acetated Ringer
2
1
and 0.41 (0.03) mmol.l
(n ˆ 5),
respectively. Figure 10 shows a good
correlation between Mg (% of con-
trol) and the water balance per body
weight. The water balance (ml.kg
was calculated by the equation:
infusion volume) 2 (blood loss)
(urine volume)/(body weight).
The correlation predicts that the
2
1
)
(
2
21
water balance of 50 ml.kg
can
21
21
reduce Mg to 75% of control. The
results suggested that the magnesium
supplementation should be considered
when a large amount of magnesium-
free fluid is infused during general
anaesthesia.
solution at 15 ml.kg .h (0±60 min),
21
2
1
1
0 ml.kg .h
(61±120 min) and
ml.kg .h (after 121 min). Arterial
21
21
5
blood (3 ml) was sampled from a radial
artery cannula using blood gas
a
sampling kit containing 7 iu of heparin
lithium (QuickLitee; Marquest Medical,
Englewood, CO, USA) for every
R. Sasaki
K. Hirota
A. Masuda
5
00 ml of fluid administration. Serum
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Correspondence
.
...............................................................................................................................................................................................................................................
hypotension (mean arterial pressure
75 mmHg) and hyperventilation
arterial carbon dioxide pressure
36 mmHg). Owing to fetal brady-
^
(
^
cardia, the indication for scheduled
craniotomy was revised and emergency
Caesarean section was performed. The
neonate was delivered 70 min after
induction of anaesthesia; the Apgar
scores were 2 and 7 at 1 and 5 min,
respectively. Following intubation and
ventilation, the neonate emerged from
anaesthesia 12 h later. After Caesarean
section, an external ventricular drainage
system was installed and craniotomy and
clip obliteration of the aneurysm were
carried out consecutively. Due to the
intracranial oedema, the patient was
sedated with midazolam and fentanyl
and hyperventilated for the next 5 days.
Postoperative course was uneventful.
Only minor neurological deficits were
recognised which completely recovered
within the first 2 months postopera-
tively.
Aneurysmal subarachnoid haemor-
rhage during pregnancy is an infre-
Figure 11 Axial CT scan without contrast showing a severe aneurysmal subarachnoid quent complication, presenting
haemorrhage that fills the basal cisterns and produces a hydrocephalus (note the marked hazard to both the mother and the
brain swelling).
a
fetus. Over 80% of aneurysmal subar-
achnoid haemorrhages during preg-
nancy occur during the second and
third trimester [4]. Successful treatment
requires thorough diagnostics and close
monitoring in a flexible teamwork to
address both the varying maternal and
fetal needs. The fundamental aims of
anaesthesia are to maintain oxygenation
and stable systemic, cerebral and pla-
cental haemodynamics and to avoid
increased intracranial pressure. In the
situation of acute fetal distress, as
occurred in the present case, one
must, at any time, be prepared for
immediate Caesarean section. Under
these circumstances, it has proven
helpful to have a special neonatal care
team and unit to care for the `co-
anaesthetised' baby delivered at an
unexpected time during the procedure.
We strongly encourage the develop-
ment of working relationships for
guidelines for the management of
aneurysmal subarachnoid haemorrhage
Figure 12 Cerebral angiography showing an aneurysm of the right internal carotid and similar cerebrovascular diseases
artery (arrow).
during pregnancy.
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Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
K. Jaeger
H. Ruschulte
Community Hospital, Mbarara District,
Uganda.
Acta Anaesthesiologica Scandinavica 1984;
28: 351±6.
K. M uÈ hlhaus
M. Tatagiba
Hannover Medical School,
D-30625 Hannover,
Germany
From November 1992 to October 2 Zimmermann H. Ketamine drip
1994, a total of 65 operations and 347
minor surgical interventions were per-
formed; 34.9% of them were obstetric
procedures. A single shot of ketamine
anaesthesia for Caesarean section.
Report on 200 cases from a rural
hospital in Zimbawe. Tropical Doctor
1988; 18: 60±1.
E-mail: jaeger.karsten@mh-
hannover.de
was sufficient for short manoeuvres, 3 Klafta JM, Zacny JP, Young CJ.
e.g. incision and drainage, removal of
foreign bodies or painful redressing in
burn patients. Repeated doses of
ketamine were given in lower-segment
Neurological and psychiatric adverse
effects of anaesthetics: epidemiology
and treatment. Drug Safety 1995; 13:
281±95.
References
Caesarean section (LSCS), laparotomy, 4 Mahomedy MC, Downing JW, Jeal
1
Kofke WA, Wuest HP, McGinnis LA.
Cesarean section following ruptured
cerebral aneurysm and
emergency trepanation, and dilatation
and curettage. The drug was generally
available, cheap and easy to store. In
DE, Allen PJ. Ketamine for anaesthetic
induction at Caesarean section. South
African Medical Journal 1976; 50: 846±8.
5 Green SM, Clem KJ, Rothrock SG.
Ketamine safety profile in the
neuroresuscitation. Anesthesiology 1984;
6
21
most patients, a dose of 0.5 mg.kg
0: 242±5.
was sufficient to induce general anaes-
thesia. Additional doses for maintenance
were half the initial dose at 10±15 min
intervals. During anaesthesia, patients
breathed ambient air. It was difficult to
assess the accurate stage of ketamine-
2
3
Lennon RL, Sundt TM Jr, Gronert
GA. Combined cesarean section and
clipping of intracerebral aneurysm.
Anesthesiology 1984; 60: 240±2.
developing world: survey of
practitioners. Academic Emergency
Medicine 1996; 3: 598±604.
Conklin KA, Herr G, Fung D.
Anaesthesia for caesarean section and
cerebral aneurysm clipping. Canadian
Anaesthetic Society Journal 1984; 31:
induced
anaesthesia.
Monitoring Pressure ulcers during labour:
during anaesthesia was restricted to the effect of epidural analgesia
intermittent measurement of blood
4
51±4.
We were interested to read the recent
letter regarding the occurrence of
pressure ulcers during labour (Offori
pressure, pulse rate and respiratory
rate. Slight increase in muscle rigidity,
blood pressure, heart rate and respira-
tory rate were frequently detected.
Excessive salivation required atropine.
Eye opening, nystagmus and sponta-
neous movements were common.
Frightening hallucinations were infre-
quent and, when present, not comple-
tely controlled by benzodiazepines.
Generally, in LSCS diazepam was not
administered before the umbilical
chord was clamped [4]. Consequently,
neonates delivered by LSCS did not
show drug-induced depression of
Apgar score as compared with sponta-
neously delivered babies. Despite the
absence of monitoring with ECG and
pulse oximetry, there were no life-
threatening complications, e.g. laryn-
gospasm or aspiration associated with
ketamine-induced anaesthesia [5].
4
Reichman OH, Karlman RL. Berry
aneurysm. Surgical Clinics of North
America 1995; 75: 115±21.
&
Popham. Anaesthesia 2000; 55: 194).
We would like to reassure them that
they are not alone in this problem. We
would also like to share our experience
of this problem, particularly because it
is not confined to the labouring
parturient as can be seen from another
letter in the July issue of this journal
[1].
The phenomenon of pressure ulcera-
tion occurring in patients with `low-
dose' epidurals is on the increase within
maternity units across the country [2±6]
and will probably be seen on other
hospital wards too. However, this is not
new and was reported as long ago as
1985 [7, 8].
In 1997, five cases of pressure ulcers,
which appeared during labour, were
investigated in the Royal Cornwall
Hospital. In all cases, the women had
normal vaginal deliveries with epidural
analgesia for pain relief. In all cases the
epidural was low-dose bupivacaine with
opioid given intermittently rather than
by infusion. Since then, anecdotal evi-
dence has been gathered from 13
Peripartum general anaesthesia
without tracheal intubation
Ezri et al. recently reported ketamine-
induced anaesthesia without tracheal
intubation during obstetric procedures
in the peripartum period. The
observed risk of aspiration was com-
parable to that occurring in the general
surgical population (Ezri et al. Anaes-
thesia 2000; 55: 421±6). Nowadays, in
many European countries, ketamine is
administered, if at all, under emergency
conditions in trauma patients. In areas
with a lack of specialist staff and
limited equipment, as is common in
the developing world, ketamine may
still serve as a sole anaesthetic during
various surgical procedures [1, 2]. It
produces a state of deep analgesia and
dissociative anaesthesia in non-venti-
lated patients with preserved brainstem
reflexes [3]. I wish to report my
W. Lederer
University Hospital of Innsbruck,
A-6020 Innsbruck, Austria
References
experience
primary anaesthesia at Rushere
with
ketamine-based 1 Lenz G, Stehle R. Anesthesia under
field conditions. A review of 945 cases. hospitals around the country, which
1140
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Anaesthesia, 2000, 55, pages 1127±1143
Correspondence
.
...............................................................................................................................................................................................................................................
had also discovered similar problems. tolerance and it is vital that each A novel method for epidural
Our main conclusion was that direct woman is assessed individually and a catheter fixation
pressure alone is not the major cause of
intrapartum pressure damage.
care plan devised accordingly. A dyna-
mic and flexible approach to the care of
the woman in labour, especially one
with an epidural for pain relief, is
essential. We have seen no further
problems since the five cases identified
in 1997.
Epidural catheter migration is
a
For many hospitals, pressure area care
within maternity units is not considered
as important as other aspects of care;
it is not expected that healthy young
women in childbirth will develop
pressure ulcers. Specific incidence mon-
itoring often excludes maternity wards
for this very reason. Friction and shear
forces can destroy the microcirculation
within the epidermis especially in
sodden skin tissue, which is highly
mobile, such as the buttocks of women
in labour. This combination may cause
damage within a matter of a few
minutes in some cases [9]. The con-
tinued use of plastic draw sheets and
common problem that can inconve-
nience the anaesthetist and have
potentially devastating consequences
for the patient. Following insertion
into the epidural space, the catheter
can be simply taped with an adhesive
dressing or tunnelled subcutaneously
to reduce the incidence of migration
[1]. Numerous fixation devices have
been designed to tether the catheter
to the skin, including simple adhesive
devices [2] and more complex cathe-
ter clamps that adhere to the skin
(Lockitw, Portex, UK). Devices such
as a balloon-tipped catheter (Patent
No. US4973305) and a self-retaining
catheter with wings that can be
H. Newton
M. D. Mitchell
Royal Cornwall Hospital,
Truro TR1 3LJ,
UK
References
poor quality incontinence pads further 1 Alexander R. Pressure sore following
increases friction and shearing by adhe-
sion to the skin and trapping moisture.
We recommend that their use be
discontinued.
In our experience, the quality of the
delivery mattress further increases the
risk of pressure ulcer formation. Some
mattresses are too hard or too soft and
some have a poor shape. Both these
low-dose epidural infusion. Anaesthesia expanded outwards at the tip (Patent
No. EP0931559) have not reached
the market. It appears that the weak
link in adhesive catheter fixation
techniques is in the tethering of the
adhesive to the skin. Perspiration and
shear forces combine to reduce adhe-
sion over time. Directly suturing the
catheter to the skin can cause occlu-
sion and fracture of the catheter wall
and so is not routinely used [2]. We
2
000; 55: 709±10.
2
3
Malone C. Pressure Sores in the labour
ward. RCM Midwives Journal 2000; 3:
2
0±3.
Butcher M. Identifying and combating
the risk of pressure. Nursing Standard
2
000; 14: 58±63.
factors increase either direct pressure or 4 Torrance E. Pressure sores. RCM
shearing forces or both. Combine this
Midwives Journal 2000; 12: 60.
with lack of knowledge of the problem, 5 Newton H. Tissue Viability ± Changing describe a simple, cheap and highly
and we have a recipe for the continuing
occurrence of pressure ulceration. All
these risk factors are worsened in the
presence of reduced sensory perception
that exists during epidural analgesia:
tissue pressure, friction and shear all
remain unrelieved in the absence of
movement induced by pain.
effective fixation technique that
attaches at the point of insertion
with a single suture.
practice within the Delivery Suite of a
Maternity Unit. Presentation to:
European Wound Management
Association Conference. Harrogate,
A 2-cm length of robust adhesive
dressing (Veni-gard, ConMed, USA) is
wrapped around the catheter at the
point of insertion. Following infiltration
with local anaesthesia, a single 2.0 silk
stitch is passed through the dressing and
sutured to the skin adjacent to the
catheter entry site (Fig. 13).
1998.
6
Smet IG, Vercauteren MP, DeJongh RF.
Pressure sores as a complication of
patient controlled epidural analgesia
after caesarean delivery. Regional
Anaesthesia 1995; 21: 338±41.
In our unit, we have stopped using
certain delivery mattresses and incon-
tinence sheets and, more importantly,
developed a training awareness pro- 7 Punt CD, Van Neer PA, Lange S.
We tested this technique using an
gramme specifically to target problem
areas within the hospital. In the labour
ward, an assessment of risk using simple
trigger factors has proved most effective.
Education and training for midwives
should be available and relevant to the
women's needs. There is very little
evidence to suggest that epidural
analgesia in labour, even using `low-
dose' techniques, may be a factor in
the formation of pressure ulcers. There
are many variables that affect tissue
Pressure sores as a possible complication in-vitro porcine skin model. A weight
of one pound (0.45 kg) could be
of epidural analgesia. Anesthesia and
reliably held suspended from the
catheter (Fig. 14). Further force
Analgesia 1991; 73: 657±79.
8
9
Pither C, Hartick C, Prithvi P. Heel
applied to the assembly caused the
sores in association with prolonged
catheter to stretch then ultimately slip
from the adhesive tethering. This far
epidural analgesia. Anesthesiology 1985;
6
3: 459.
exceeds the forces one would expect
to be produced in clinical circum-
stances.
Newton H, Butcher M. Investigating
the risk of pressure damage during
childbirth. British Journal of Nursing
2000; 9: S20±6.
Securing the catheter at its point of
entry into the skin does not, however,
q 2000 Blackwell Science Ltd
1141

Correspondence
Anaesthesia, 2000, 55, pages 1127±1143.
.
...............................................................................................................................................................................................................................................
4
5
Coupe M, Al-Shaikh B. Evaluation of a
new epidural fixation device.
Anaesthesia 1999; 54: 98±9.
Beilin Y, Bernstein HH, Zucker-
Pinchoff B. The optimal distance that a
multioriface epidural catheter should be
threaded into the epidural space.
Anesthesia and Analgesia 1995; 81:
301±4.
Tunnelled epidurals
Your editorial on tunnelled epidurals
(Kumar
&
Chambers. Anaesthesia
000; 55: 625±6) was most interest-
2
ing, although the methods used to
achieve this end were rather complex.
I have always found the easiest way is
to use a tunnelling rod such as the
one supplied by B Braun Medical,
France.
G. R. Harrison
Figure 14
Queen Elizabeth Hospital,
Birmingham B15 2TH,
UK
women was associated with the highest
incidence of satisfactory analgesia [5].
This length of catheter insertion in a Sleepers for body piercing
sitting patient with a deflexed back
would allow for the possibility of a Metal body jewellery represents
a
degree of initial migration of the potential hazard to the patient pre-
tethered catheter out of the epidural senting for surgery, either through
space. Our clinical experience using displacement from sites in or near
the technique in 15 cases has indicated the oro-nasal cavity [1], or by
that this simple epidural catheter fixa- presenting a potential earth for dia-
tion technique is successful in prevent- thermy. Although plastic sleepers are
Figure 13
ing migration.
available, few patients have these
available when they present for sur-
gery [2]. Current best practice would
suggest that metal body jewellery
should be removed prior to the
induction of anaesthesia, or where
this is not possible, covered with
adhesive tape; one or other of these
solutions is possible in the vast
majority of cases. Occasionally, the
piercing is situated in the surgical
field or is too recent for the
subcutaneous track to have fully
epithelialised, and on these (rare)
occasions I would suggest that the
intravenous portion of a cannula does
the trick nicely (Fig. 15). Care should
B. Poulton
P. Young
Norfolk and Norwich Hospital,
Norwich NRI 3SR,
UK
prevent movement of the skin relative
to the epidural space. An epidural
placed in the sitting position in an
obese patient will retract into the
subcutaneous tissues on returning the
patient to the lateral recumbent due to
an increase in the distance between the
References
point of skin puncture and the point of 1 Kumar N, Chambers WA. Tunnelling
entry into the epidural space [3, 4].
This positional migration is of 1.0±
epidural catheters: a worthwhile
exercise? Anaesthesia 2000; 55: 625±6.
2
.5 cm and could itself result in out- 2 Sclunitt LG, Ullman DA. A method of
ward catheter migration unless the
securing epidural catheters. Anesthesia
catheter is stitched in the deflexed
and Analgesia 1989; 69: 856±7.
recumbent position. Beilin et al. 3 Gartrell P. Disappearing epidural
showed that a catheter inserted 5 cm
into the epidural space of labouring
catheters. Anaesthesia and Intensive Care be taken when removing the metal
1992; 20: 121±2.
ring or stud in a recent piercing, as it
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Anaesthesia, 2000, 55, pages 1127±1143
Correspondence
.
...............................................................................................................................................................................................................................................
Figure 16
Figure 15
can be quite impossible to recannulate
the subcutaneous track. In these cases
the plastic cannula can be guided into
place by choosing a cannula diameter
that is the same size as the ring or
stud, or only slightly smaller, and
I. Mackenzie
John Radcliffe Hospital,
Oxford OX3 9DU, UK
Erratum
In the correspondence `Pressure sore
following low-dose epidural infusion'
(Anaesthesia 2000; 55: 709±10), the rate
of epidural infusion of bupivacaine 0.1%
References
then use the ring or stud to guide 1 Girgis Y. Hypoxia caused by body
the cannula into place (Fig. 16). Once
piercing. Anaesthesia 2000; 55: 413.
in place the hub of the cannula can 2 Ferguson H. Body piercing. British
2
1
and fentanyl 2 mg.ml
should read
21
2
1
10 ml.h
published.
and not 10 ml.min
as
simply be cut off.
Medical Journal 1999; 319: 1627±9.
q 2000 Blackwell Science Ltd
1143