Full text of DOI:10.1046/j.1365-2044.2000.01798-29.x

Anaesthesia, 2000, 55, pages 1213±1235
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.
Correspondence
Noise in the MRI scanner
of 103 dB at the centre of an MRI those having prolonged or repeated
using a gradient-echo pulse sequence. scans, those with existing acoustic
We welcome the paper by McBrien and This figure, according to HSE regula- damage and those receiving amino-
colleagues (McBrien et al. Anaesthesia tions, would allow a maximum daily glycoside antibiotics.
000; 55: 737±43) in which they exposure of 15±30 min.
2
highlight concern over the exposure to
We are currently attempting to be
The acoustic noise can be a tapping, more scientific in our own approach to
occupational hazards such as magnetic knocking or chirping and is produced acoustic protection by involving our
fields, unscavenged anaesthetic gases and by rapid alteration of currents within hospital's Health and Safety Department
noise. We note with interest the attitude the gradient coils. The noise can in measuring the noise emitted by our
of anaesthetists towards their own frighten children (hence the need for 1.5-Tesla MRI and the effectiveness of
personal safety, in particular, the group sedation or general anaesthesia), can various noise ablation techniques. We
of 22 anaesthetists who `always' or make existing tinnitus worse and can intend to submit the results for publication
`
frequently' remained in the scanning lead to temporary hearing loss. In a in due course.
room. Of this group, 19 of 22 identified study of 14 patients without acoustic
Finally, we endorse the comments of
no potential for harm from either protection and 10 with acoustic protec- the authors of this paper with regard to
magnetic field or acoustic noise, and tion, six patients (43%) of the group the provision of recommendations
none of the 22 identified acoustic noise without protection suffered temporary for standards of anaesthesia for MRI
specifically as potentially harmful. The hearing loss whilst only one in the from such a body as the Association of
authors comprehensively discuss the group with protection suffered a tem- Anaesthetists.
problem of occupational noise exposure porary hearing loss [6]. It is worth
and refer to regulations contained noting that a maximum average daily
within the Health and Safety Executive exposure of 90 dBA is designed to
G. Morton
C. Gildersleve
University Hospital of Wales,
Cardiff CF14 4XW, UK
(
HSE) Noise at Work Regulations [1] protect only 85% of the exposed
requiring employers to take specific population from significant hearing
action to reduce the noise exposure of loss [2]. Noise reduction is urged by
employees. Similarly, it is our duty as the HSE to all employers and employ-
anaesthetists to ensure that we take ees. The following active and passive
action to minimise the risk of acoustic noise reduction techniques may be
damage to our anaesthetised patients. employed.
References
Health and Safety Executive. Noise at
Work Regulations. London: HMSO,
1
2
1990.
This is perhaps easy to forget amongst
Active: computer-generated low-fre-
Hurwitz R, Lane SR, Bell RA, Brant-
Zawadzki. Acoustic analysis of
the range of problems we instinctively quency pulsatile sound waves that are at
recognise as unique to anaesthesia for 1808 out of phase with the anticipated
MRI and are discussed in depth in this noise. This can offer a reduction of
paper. However, if only 2 of 46 units approximately 10 dB through headsets.
gradient-coil noise in MR Imaging.
Radiology 1989; 173: 545±8.
3
4
McJury MJ. Acoustic noise levels
generated during high field MR
Imaging. Clinical Radiology 1995; 50:
(
Table 7) identify the potential harm
Passive: foam earplugs, if sited cor-
from noise with respect to their own rectly, may reduce a continuous non-
personal safety, is this mirrored by a impulsive noise of 92 dB to 63 dB
similar attitude towards the acoustic (product data).
331±4.
McJury MJ, Blug A, Joerger C,
Condon B, Wyper D. Short
safety of their patients?
A snapshot survey of noise ablation
In 1989, Hurwitz et al. [2] measured techniques used in 20 MRI suites in the
noise in MRI systems from 0.35 to 1.5 UK where general anaesthesia was
Tesla. The measured noise ranged from provided for MRI is shown in Table 1.
8
They concluded that the noise levels, units identified potential harm to them-
communication: acoustic noise levels
during magnetic resonance imaging
scanning at 1.5T. British Journal of
Radiology 1994; 67: 413±15.
2 to 93 dB on an A-weighted scale. It is reassuring that while only two of 46
although annoying, posed minimal selves from acoustic noise, in our small 5 Shellock FG, Morisoli SM, Ziaratti M.
threat of permanent hearing loss. How- study only three out of 20 units (15%)
ever, with the trend towards stronger did not use a noise reduction technique.
magnets and `noisier' sequences, higher We do, however, urge all anaesthetists
noise levels have been measured [3, 4]. involved in providing anaesthesia for
Measurement of acoustic noise during
MR Imaging: Evaluation of the six
`worse case' pulse sequences. Radiology
1994; 191: 91±3.
Shellock et al. [5] measured the six MRI to be aware of the acoustic risk 6 Brummett RE, Talbot JM, Charhaus P.
worse case' sequences and found levels to anaesthetised patients, in particular Potential hearing loss resulting from
`
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Anaesthesia, 2000, 55, pages 1213±1235
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Table 1 Results of a survey of noise ablation techniques used in 20 MRI Units in the flow meters (no rotameters) and no
UK.
calculated oxygen concentration on the
anaesthesia delivery unit screen, we were
unsure of the exact composition of the
Noise ablation
technique
No. of units
fresh gas. In the meantime, a spare anae-
sthetic machine was brought into the
operating theatre and the surgery com-
pleted using the replacement machine;
the new machine's self-check procedure
showed up no faults in the piped oxygen
and nitrous oxide supplies. The patient
never desaturated and made an uncom-
plicated recovery.
(n ˆ 20)
Nothing
Earplugs only
3
7
5
1
3
1
Foam packing around the head
Earplugs and foam packing
Construction ear mufflers (as available from DIY warehouses)
Home made wooden head box (insulated with foam
known as `the kennel')
The AS/3 machine was promptly
serviced and the problem rectified. Datex
recommends calibration of its machines
every 6 months. In our department, we
calibrate our AS/3 units every 3 months
and give them a full service once a year.
This case illustrates that despite following
the manufacturer's servicing guidelines,
equipment failure does occur.
MR Imaging. Radiology 1988; 169:
39±40.
Certainly contamination of nitrous
oxide has been a problem in the past.
Visitors to the current exhibition in the
Association's Museum will see that
between 1927 and 1939 every cylinder
of nitrous oxide supplied by BOC had a
certificate of the purity of its contents
attached. So my question is, once
nitrous oxide of the requisite purity is
in the cylinder, what goes wrong with
it, and how long does it take to become
unfit for use?
5
7
Goldman AM, Gossman WE,
Friedlander PC. Reduction of sound
levels with antinoise in MRI Imaging.
Radiology 1989; 173: 549±50.
On discussing the problem with
Datex, it appears that the likely problem
was a leak in the vaporiser system. We
had checked that the vaporiser cassette
was correctly seated, but apparently
leaks can still occur. This would mean
that the oxygen concentration set on
the electronic flow meters would differ
from the concentration measured at the
patient end of the delivery system. If
this occurs, the AS/3 automatically
switches itself into safe mode where
Date-expired nitrous oxide
cylinders
I was intrigued by Dr Ranasinghe's
letter (Ranasinghe. Anaesthesia 2000;
5: 819±20). What criteria determine
the shelf life of a cylinder of nitrous
oxide, and on what scientific basis? I ask
because in the Journal of Dental Science
D. Zuck
London N12 8BA, UK
5
Failure of Datex AS/3
anaesthesia delivery unit
1
877; XX: 662, Dr J. Ottley Atkinson
reported having administered nitrous
oxide on separate occasions to two
patients, from Coxeter's 100-gallon
cylinders 3 years and 7 days and
21
We report the failure of a Datex AS/3 4 l.min of oxygen are delivered to the
anaesthesia delivery unit. An ASA 1 patient and the rotameters and vaporiser
patient was having a general anaesthetic taken out of the circuit. The problem
3
years and 4 months old, and found
with the AS/3 is that it does not tell you
that it has switched into safe mode,
hence our confusion.
for an orthopaedic manipulation under
anaesthesia; surgery was progressing
uneventfully. Suddenly, the oxygen and
the effects satisfactory in every way. He
commented that this spoke much for
the retaining power of Messrs Coxeter's nitrous oxide electronic flow meters,
Two aspects of this case are worth
bottles. It is interesting that even in isoflurane agent monitor and inspired highlighting:
those very early days, cylinders were oxygen concentration monitor screen 1 The absence of rotameters in some
labelled with the filling date, one of went blank. An audible alarm sounded modern anaesthetic machines means that
which is quoted.
with a caution symbol displaying `Fresh you have no way of measuring fresh gas
Twenty years later (Journal of Dental gas unit failure'. All other physiological flow if there is an electronic failure.
Science 1897; XL: 922) there was a parameters being monitored (heart rate, 2 When new anaesthetic machines are
report copied from an American jour- ECG, oxygen saturation, non-invasive purchased, a lot of emphasis is placed on
nal, Dental Cosmos, of an SS White blood pressure, end-tidal carbon dioxide) getting to know how they work
cylinder 19 years old, the contents of remained unchanged. The isoflurane and normally. Perhaps we should also be
which worked perfectly. Considering nitrous oxide were promptly turned off, learning how to deal them when
that the dentists concerned were reserve oxygen cylinder turned on, and they are faulty. Datex gives tutorials to
obviously very occasional anaesthetists, the patient ventilated with what we staff members when they deliver a new
and that the nitrous oxide in the thought was 100% oxygen. The oxygen anaesthetic machine to a hospital. These
cylinders of those dates was much cylinder gauge pressure indicated that the tutorials emphasise troubleshooting, as
more likely to contain contaminants cylinder was full, gas was coming out of well as normal function, of the new
than now, one does wonder.
the fresh gas outlet, but with electronic machine. Unfortunately, with regular
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staff rotations, most anaesthetists will shooting section is included in the ADU an AMBU bag to ventilate the patient,
not receive this training.
users' reference manual.
Some further clarifications with uneventfully.
and the laparotomy was completed
E. Aziz
G. M. Sanders
Medway Maritime Hospital,
Gillingham ME75NY, UK
reference to the letter from Drs Aziz
and Sanders:
While it is difficult to blame the
manufacturer for this failure, the con-
Anaesthetic agent and oxygen con- sequences of this event need considera-
centrations shown on the ADU display tion. Cleaning the blood out of all areas
are set values. Monitored values are that it reached required a `strip down' of
shown on the anaesthesia monitor (AM). the machine, which took it out of
A suspected component failure in the service for several days. A spare machine
A reply
The Datex-Ohmeda AS/3 Anaesthesia FGC can lead to a `Fresh gas unit was needed for this time.
System includes a delivery unit (ADU), failure' alarm and a safe state with N O
On a personal note, one author is
2
an anaesthesia monitor (AM) and an and agent shut off. This is a safety glad the patient's head was turned to the
optional anaesthesia record keeper system to eliminate any risk of delivery right, not the left.
The manufacturer has been informed.
(ARK). The ADU must always be used of too high N O or agent concentra-
together with an anaesthesia monitor and tions to the circuit. In such situations
the design philosophy and risk analysis are oxygen will continue to flow as set, and
based on the fact that the ADU and AM also air can be delivered if selected.
2
N. J. D. Macartney
J. Cohen
Barnet and Chase Farm Hospitals,
Enfield EN2 8JA, UK
are totally independent modules of the
O. Lassborn
system. Early this year we identified a
Quality Assurance Manager,
reliability problem in the ADU fresh gas
Datex-Ohmeda,
control unit (FGC). This problem could
Stockholm 2000-08-29, Sweden
lead to a `Fresh gas unit failure' and
Expiratory dates on anaesthetic
gas cylinders
further put the FGC into a safe state.
The reported problem from Medway
Another case of anaesthetic
Maritime Hospital is indicated to be of
machine failure
I am writing further to my recent letter
(Ranasinghe. Anaesthesia 2000; 55:
this kind. This problem was identified
8
19), which highlights the fact that gas
to the FGC software and upgraded
I should like to report another cause
software has been designed and imple-
of anaesthetic machine failure. A patient
mented in all units with a corrective
was taken straight to the operating
field action as from April this year.
expiry dates on cylinders attached to
anaesthetic machines are not routinely
checked as part of the `cockpit drill'.
It is not possible to see the gas expiry
date on a BOC cylinder (British Oxygen
Company Gases) whilst it is attached to an
anaesthetic machine. This is because
BOC attaches the label carrying the
expiry date to the side of the cylinder
valve block and this is obscured by the
anaesthetic machine pin-index yoke.
Therefore, the only way to perform this
check would be to remove each cylinder
in turn and read the expiry date, which
would be cumbersome.
Gas cylinders are currently supplied
to our Hospital Trust by Linde Gas UK
Ltd. The gas expiry date is marked in
black on a white label placed on the
cylinder shoulder, making it clearly
visible, even with the cylinder attached
to the anaesthetic machine.
theatre from casualty, having presented
In response to the two comments of
with massive upper gastrointestinal
Drs Aziz and Sanders:
1
haemorrhage. It had been decided that
The electronic measuring of fresh gas
flows makes it possible to include a more
advanced safety system of delivered flow
he required endoscopy and probable
laparotomy. While a large-bore triple-
lumen central venous line was being
inserted in the left subclavian vein prior
to induction of anaesthesia, the patient,
whose head was turned to the left,
complained of nausea. He was asked to
turn his head to the right to keep the
area clean, but suddenly vomited
copious blood. This completely covered
the anaesthetic machine (a Datex AS/3
ADU/AM). Anaesthesia was induced
rapidly in order to protect the patient's
airway. Invasive monitoring was then
inserted, and it was found that it was not
composition. This design allows a
hypoxic guard system in any O /N O/
anaesthetic agent mixture (important
when agents with high concentrations
are used).
2
2
Our experience is that electronically
displayed fresh gas flows show high
reliability. In an event of display failure,
it is most important to monitor and
adjust the inspired gas concentrations,
shown on the patient monitor. Espe-
cially when a low-flow rebreathing
system is used, the fresh gas concentra- possible to obtain pressure readings
tions can differ significantly from the because blood had entered the module
inspired gas concentrations.
housings causing short circuits. A por-
2 We strongly support a regular training table monitor was obtained. It was then
programme, including handling of noticed that the electronic vaporiser was
emergency events and troubleshooting. now malfunctioning and could not be
This programme should be mandatory used because of blood in the workings.
for all anaesthetists. A special trouble- The machine was changed while using
Irrespective of the gas supplier, all
cylinders attached to anaesthetic
machines should have gas expiry dates
that are clearly visible.
D. N. Ranasinghe
Colchester General Hospital,
Colchester CO4 5JL, UK
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Anaesthesia, 2000, 55, pages 1213±1235
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Unusual pulse oximetry
waveform
possibility. The patient also showed no
signs of shivering, tremors or convulsions.
As with all problems with saturation
H. Brownlow
J. Bell
Salisbury District Hospital,
Salisbury SP2 BJ, UK
On transferring a patient from the probe readings or traces, the first place
intensive care unit to the operating to look to solve a problem is the probe
theatre for the closure of a compound itself. On moving the patient's blankets
femoral fracture, the following unusual it was noticed that the two probes were
References
pulse oximetry trace was obtained on adjacent fingers. When the position 1 Hanowell L, Eisele JH Jr, Downs D.
(
Fig. 1). The patient was at the time of the non-adhesive probe was changed
connected to a Nellcor Oxisensor II D- so as not to be on adjacent fingers, a
5 pulse oximeter probe that was being normal trace was obtained.
monitored by means of a Propak 100 for
It is common knowledge that visible
Ambient light affects pulse oximeters.
Anesthesiology 1987; 67: 864±5.
Amar D, Neidzwski MS, Wald A, Finck
D. Flurescent light interferes with pulse
oximetry. Journal of Clinical Monitoring
1989; 5: 135±6.
2
2
the transfer. As it was the intention to light has the ability to interfere with the
continue monitoring this patient on the reading or trace of such probes and that
return to the intensive care by means of this is far worse if the light source is
this same adhesive oximeter probe, the pulsatile. This can occur with ambient
original probe was left in place whilst light, especially if it is fluorescent [1, 2].
A modification to the Codmane
Microsensore Skull Bolt Kit
other monitoring was connected to the
Our abnormal trace can be explained
patient. Unknown to the two accom- by the fact that the two emitting diodes
panying anaesthetists, a further probe when placed on adjacent fingers were
was connected to the adjacent finger by acting as a source of extraneous light for
the operating department assistant each other and were being picked up by
The use of intracranial pressure mon-
itoring in the management of closed
head injuries is increasing in intensive
care units [1]. The placement of
intracranial pressure monitoring devices
has traditionally been the preserve of
(Fig. 2). A Datex AS/3 was monitoring their two semiconductor photo detec-
this. The patient's blankets obscured the tors; hence, the duplicity of the abnor-
adjacent position of these two saturation mal trace on the two monitors. The
probes from the two anaesthetists. The assembly of the probe should be such the neurosurgeons. However, more
abnormal trace was first thought to be that it is protected from light over the intensivists are now undertaking this
due to a problem with the Propak 100 range of wavelengths to which the procedure. We wish to report a mod-
machine, but this was ruled out when detector is sensitive, typically between ification to the Codmane Microsen-
the abnormal trace was duplicated on 660 nm (red) and 940 nm (near infrared). sore Skull Bolt Kit with the aim of
the Datex AS/3 monitor attached to the This was clearly not the situation when improving the safety of use of the above
second saturation probe.
Mechanical artefacts either voluntary
placed on adjacent fingers.
kit by non-neurosurgeons. Therefore, this
Knowledge and awareness of this modification is relevant to anaesthetic
or involuntary such as shivering, tre- abnormal trace could help save valuable practice in the field of intensive care.
mors or convulsions are known to time in searching for erroneous causes
The human skull has great variability
produce such abnormal traces, but as of the trace at a time when diversion of in thickness when measured at different
the patient had just received a paralysing attention away from the patient could points. Variation also exists between
dose of vecuronium this did not seem a be dangerous.
different sexes, ages and racial groups
Figure 1
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.
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References
1
2
3
Granger C, Hancox D. The General
ICU Management of Patients with Severe
Traumatic Brain Injury. Association of
North West Intensive Care Units
(ANWICU) Guidelines.
Adeloye A, Kattan KR, Silverman FN.
Thickness of the normal skull in the
American Blacks and Whites. American
Journal of Physical Anthropology 1975; 43:
23±30.
Hwang K, Kim JH, Baik SH. The
thickness of the skull in Korean adults.
Journal of Craniofacial Surgery 1999; 10:
Figure 2
395±9.
[2]. In a Korean study [3], the thickness
We would like to acknowledge the
of the frontal bone measured at a point help of Mr I. M. Barker for engineering
approximating the point of insertion of
an intracranial pressure monitor was
the new depth guides.
Cricothyroidotomy comments
G. N. Jones
J. M. Barker
6.63 ^ 1.77 mm.
In the Codman Microsensor Skull
In describing modifications to a central
North Manchester General Hospital, venous cannulating needle to allow it to
Manchester M8 5RB, UK function as a needle for cricothyroidotomy,
Bolt Kit we have noted that the grub
screw on the depth guide collar does not
easily tighten on to the drill bit if the
depth guide collar is being set for a
shallow depth. This is because the grub
screw is trying to seat on the actual
cutting portion of the drill, the first
1
5 mm (Fig. 3). The minimum depth
that can be set where the grub screw is
not mounted on the cutting portion of
the drill using the Codman Microsensor
Skull Bolt Kit is 14 mm. We therefore
propose that the depth guide be elon-
gated with the grub screw situated away
from the cutting drill bit. This would
surely make this piece of equipment
easier to handle and would not prove
expensive to modify. Two depth guides
were manufactured to assess the change
required. In the light of the Korean
study [3] the longest depth guide
would be most appropriate, allowing a
minimum depth setting of 5 mm
(Fig. 3). We have submitted our recom-
mendation to Johnson Johnson
&
Medical Ltd, who manufacture the
Codman Microsensor Skull Bolt Kit.
We would add the reminder that the
use of modified equipment without the
approval of the manufacturers transfers
any product liability from the manufac-
turers to the medical personnel using
the modified equipment. The modified
equipment that we have made has not Figure 3 Orignal Codman drill bit and depth guide with new depth guide elements
yet been used.
shown against millimetre scale.
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Anaesthesia, 2000, 55, pages 1213±1235
.
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Drs Dubey and Kumar (Dubey & Kumar.
Anaesthesia 2000; 55: 702±4) make points
that deserve comment.
Dumfries and Galloway Royal
Infirmary,
Dumfries DG1 4AP, UK
cian had not reviewed her. The most
alarming fact was that she had under-
gone tracheal intubation on two recent
occasions with no documented problems.
Obstructive lesions of the trachea
typically produce dyspnoea and wheez-
ing, and do not produce symptoms until
the diameter of the trachea is reduced to
less than 0.5 cm. The flow-volume loop
is a reliable diagnostic test for differ-
entiating fixed from variable obstruction
and intrathoracic from extrathoracic
obstruction. From the evidence avail-
able, it would appear that our patient
probably had a fixed extrathoracic
obstruction but with a symptomatic
variable component. In this case, flow
during inspiration is reduced (resulting
from the Venturi effect) whilst expira-
They mention that `the side port of
the needle works as a port for exhalation
to facilitate carbon dioxide elimination.'
References
Physics precludes this. Intratracheal pres- 1 Advanced Life Support Group.
sure in the passive expiratory phase is less
than 2.9 kPa (30 mmHg) and the dia-
meter of the side port is too small to allow
effective gas flow to contribute to carbon
dioxide removal [1]. Safe expiration must 2 Ryder IG, Paolini CCE, Harte CC.
therefore be accomplished through the
patient's glottis.
Procedures. Airway and Breathing. In:
Advanced Paediatric Life Support. The
Practical Approach. London: BMJ
Publishing Group, 1997: 189±218.
Emergency transtracheal ventilation:
assessment of breathing system chosen
by anaesthetists. Anaesthesia 1996; 51:
Dubey and Kumar describe that the
needle can function as a conduit for jet
ventilation with an arrangement of
needle ± syringe barrel ± cuffed tracheal
tube `connected to the anaesthetic
machine to allow ventilation of the
lungs using the flush valve as a jet
injector.' They do not mention how the
tracheal tube connects to the flush valve
of the machine in a practical way. If
connected to a machine with an inter-
posed breathing system, sufficient driv-
ing pressure is not achieved [2]. The
needle can simply be connected to
the flush valve with a length of low-
compliance oxygen tubing with some
sort of control inserted along its length,
such as a three-way tap. All connections
must be robust enough to sustain pressures
encountered in use. It is therefore
important that this is previously prepared
and immediately available.
764±8.
3
Gaughan SD, Benumof JL, Ozaki GT.
Can an anesthesia machine flush valve
provide effective jet ventilation?
Anesthesia and Analgesia 1993; 76: 800±8. tory flow is better maintained because
the increase in airway pressure splints
the trachea.
Not all that wheezes is asthma
In the end, we decided to perform
the surgery under a combined spinal±
A 66-year-old woman was listed for a epidural technique. No problems were
right total knee replacement. She had encountered. Unfortunately, despite
undergone uneventful general anaesthe- numerous verbal and written reminders,
sia and tracheal intubation 1 year and the patient was discharged home with-
4
years previously and had also under- out any attempt to investigate her neck
gone partial thyroidectomy over problems. As highlighted by Rajesh et al.
0 years ago. She suffered from asthma [1], she would clearly benefit from CT
a
2
for which she took three inhaled imaging with reconstruction to diag-
bronchodilators. Recent pulmonary nose and plan any further management.
function tests (with percentage pre-
J. M. Cupitt
North Manchester General Hospital,
Manchester, UK
dicted in parentheses) were FVC 2.3 l
(106%), FEV, 2.11 l (118%) and PEFR
21
6
.83 1.min
(128%). They were
The jet delivery system must connect
directly to the flush valve of a suitable
anaesthetic machine, which must be
capable of generating the required
pressure, and this depends on the limit
of the overpressure valve [3]. This
must be considered before approving
or attempting to use a machine as an
oxygen source for jet ventilation. If the
pressure limit is too low, ventilation is
ineffective as regards carbon dioxide
elimination, and the system functions as
an oxygen insufflator.
unable to perform flow-volume loops
due to patient difficulty.
Reference
On the morning of surgery, a chest
X-ray was ordered because the surgical
doctor felt that her chest sounded very
wheezy (Fig. 4). However, the X-ray
revealed significant tracheal narrowing,
1
Rajesh A, Aslam M, Jeyapalan K. 2±D
and 3±D reconstruction for tracheal
stenosis. Anaesthesia 2000; 55: 513±14.
maximum at the level of T , with
2
midline shift to the right. On listening Swelling in the hypopharynx as
to the woman describe how she has to a cause of difficult tracheal
crawl upstairs because she `can't get her intubation
breath', it was clear that she had mild
inspiratory stridor but no expiratory The laryngeal mask or the intubating
wheeze. Reviewing old X-rays revealed laryngeal mask has a potential role in
that the tracheal narrowing was present patients with difficult airways; never-
at least 5 years previously. The bronch- theless, its placement or tracheal intu-
odilators were clearly of no benefit to bation through it may fail [1±3]. It is
this patient. She had attended the important to elucidate possible causes
hospital for pulmonary function tests for failures to establish its role in patients
but, unfortunately, a respiratory physi- with difficult airways. We report failed
Despite these comments, we welcome
Drs Dubey and Kumar's letter, which
informs and reminds us of these important
approaches to the difficult or desperate airway.
D. R. Ball
D. Williams
P. Jefferson
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taken pre-operatively revealed swelling
in the posterior wall of the hypo-
pharynx, partially obstructing the laryn-
geal inlet (Fig. 5). The laryngeal mask
was removed and laryngoscopy was
attempted while the patient's head
and neck were kept stabilised. Tracheal
intubation was accomplished with great
difficulty by the combined use of the
laryngoscope and fibrescope.
Brain and colleagues have suggested
that tracheal intubation through the
intubating laryngeal mask may be
easier in patients with difficult airways
compared with those with normal air-
ways [4]. However, the case described
here indicates that this is not always so.
T. Asai
K. Shingu
Kansai Medical University,
Moriguchi City,
Osaka, 570-8507, Japan
References
1
Asai T. Difficulty in insertion of the
laryngeal mask. In: Latto IP, Vaughan
RS, eds. Difficulties in Tracheal Intubation,
2
1
nd edn. Philadelphia: W.B. Saunders,
997: 177±96.
2
3
4
Seto A, Aoyama K, Takenaka I, Kadoya
T. Ventilation difficulties through the
intubating laryngeal mask. Anesthesia
and Analgesia 1999; 88: 1181±2.
Figure 4
Asai T, Hirose T, Shingu K. Failed
tracheal intubation using a laryngoscope
and intubating laryngeal mask. Canadian
Journal of Anaesthesia 2000; 47: 325±8.
Brain AIJ, Verghese C, Addy EV, Kapila
A, Brimacombe J. The intubating
laryngeal mask. II. a preliminary clinical
report of a new means of intubating the
trachea. British Journal of Anaesthesia
tracheal intubation through the intubat- tip of the tube had just lifted the
ing laryngeal mask in a patient in whom `epiglottis elevating bar' at the aperture
tracheal intubation using a laryngoscope of the mask. A fibreoptic bronchoscope
or fibrescope was also difficult.
A
(diameter: 5 mm) was passed through
48-year-old woman with an these. Although it was possible to see
unstable atlanto-axial joint was sched- the vocal cords, the arytenoid cartilages
uled for posterior fixation of the were tilted toward the glottis. The
cervical spine. Because of the unstable fibrescope was inserted into the trachea,
neck, we planned to intubate the but it was not possible to advance the
trachea through the intubating laryngeal tube over it. Since we felt that the distal
1997; 79: 704±9.
mask while manual in-line head and part of the laryngeal mask might be Retrolaryngeal extension of
neck stabilisation was being applied. folded over on itself, widening the goitre in a morbidly obese
After conscious sedation was produced hypopharyngeal space and thus tilting patient leading to a difficult
by midazolam 2 mg and fentanyl 50 mg, the laryngeal inlet, the mask was with- airway
a size 4 intubating laryngeal mask was drawn for a few centimetres; however,
easily inserted with minimum discom- there was no sign of folding over. The Patients with a large goitre are more
fort to the patient. After inflation of the cuff was deflated completely to re- likely to present difficulty at intubation
cuff with 15 ml of air, a clear airway was advance the mask into the hypophar- [1]. We report a case of a difficult airway
obtained. A 7.0-mm reinforced tracheal ynx, when we found that the arytenoids in a 68-year-old, short-statured, hyper-
tube (Mallinckrodt, Athlone, Ireland) remained tilted anteriorly. Close exam- tensive, morbidly obese patient with a
was passed through the mask so that the ination of a lateral X-ray of the neck large goitre scheduled for elective
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Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
was given intravenously an hour
before the procedure and 2% lidocaine
by nebulisation, the patient was pre-
oxygenated in a 158 head-up position.
Routine monitoring was applied. The
tip of epiglottis was visualised on FFB,
but the view of the cords was obscured
by a shiny, reddish mass. The procedure
was abandoned when it was not possible
to negotiate the fibrescope around this
mass. On direct laryngoscopy under
propofol sedation, the subjective impres-
sion of the laryngoscopist was of a ball-
shaped mass (3.5 Â 3.0 cm) protruding
from the anterior wall of the oesophagus
into the hypopharynx, having no con-
nection with its posterior wall. A 6.0-mm
I.D. red rubber tracheal tube was passed
blindly between the mass and epiglottis.
Tube position was checked and anaesthe-
sia induced. Further intra-operative and
postoperative courses were uneventful.
Despite the fact that the location of the
glottis with FFB is likely to be more difficult
when the larynx is deviated [3], awake
fibreoptic-guided tracheal intubation may
be the safest technique in such situations [4].
Laryngeal mask airway and a gum elastic
bougie were not considered because of the
impossible glottic inlet conformity and the
risk of unwarranted bleeding, respectively.
Probably, the application of forward traction
on direct laryngoscopy separated the mass
and epiglottis, thus enabling us to intubate
the trachea.
Figure 5 Swelling in the posterior wall of the hypopharynx, pushing the arytenoid
cartilages toward the glottis and making tracheal intubation through the intubating
laryngeal mask (and using a laryngoscope and fibrescope) difficult.
exploratory laparotomy for a malignant airway anatomy (Fig. 6). The trachea
ovarian tumour. The goitre was pro- was compressed and posteriorly displaced
gressively decreasing in size during the at the supraglottic level, and an apparent
last 5 years without any treatment. She retropharyngeal mass pushed it anteriorly
was dyspnoeic at rest and her daughter at the glottic and subglottic level. A
reported loud snoring during sleep. CT scan of the neck and upper thorax
There was no history of nocturnal showed the tracheal compression, devia-
sleep awakenings, voice change, stridor tion and narrowing at and below the glottis
or dysphagia. Pemberton manoeuvre [2] (Fig. 7). The thyroid mass was limited to
revealed absent superior vena cava the neck, and revealed retrolaryngeal
obstruction. A cardiologist and chest extension. Airway cartilages were normal.
physician ruled out any cardiac or An ENT consultant noted mobile vocal
pulmonary cause of dyspnoea. Pulmon- cords and an adequate glottic orifice on
ary function test revealed mild airflow indirect laryngoscopy. Laboratory investi-
restriction and the ECG showed left gations including thyroid function tests
ventricular hypertrophy. Evaluation of were within normal limits.
It is known that nearly all long-
standing goitres become multinodular,
produce most extreme thyroid enlarge-
ments and extension, and are frequently
mistaken for neoplastic growth [5]. The
pressure effect of the retrolaryngeal
extension of the goitre in our patient
might have led to erosion of the anterior
oesophageal wall, while keeping the
mucosa intact. This may well represent
itself as a reddish, fragile mass with a
smooth and shiny surface.
To conclude, FFB is not the answer
to every airway problem and may be
her airway showed a short neck with a
Airway control was approached by less than ideal in certain situations [6]. This
large goitre, minimal neck extension, awake flexible fibreoptic bronchoscopy case sends a clear message to all physicians
bucked teeth, Mallampati class III airway (FFB). Arterial blood gas analysis on involved in the management of the
and a large tongue. A postero-anterior room air showed P o 10.6 kPa, P co
2
difficult airway that with all the innovative
and newly available investigative modalities
outline and lung parenchyma with base deficit of 2 and O saturation 93%. and instruments for airway control, we still
a
2
a
2
1
chest radiograph revealed normal cardiac 4.3 kPa, pH 7.40, HCO 21mmol.l
,
3
2
tracheal deviation to the left. The lateral Following premedication with aspiration have a long way to go in regard to its
neck X-ray revealed complex upper prophylaxis, glycopyrronium 0.4 mg various features and problems.
1220
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Anaesthesia, 2000, 55, pages 1213±1235
Correspondence
.
...............................................................................................................................................................................................................................................
S. Podder
A. Dutta
P. Chari
Postgraduate Institute of Medical
Education and Research,
Chandigarh ± 160012, India
References
1
2
Sebel PS. Anaesthesia for thyroid and
parathyroid disease. In: Nimmo WS,
Rowbotham DJ, Smith G. eds.
Anaesthesia. Oxford: Blackwell
Scientific Publications, 1994.
Wartofsky L. Diseases of the thyroid. In:
Fauci SA, Braunwald E, Isselbacher KJ,
et al. eds. Harrison's Principles of Internal
Medicine. New York: McGraw-Hill,
1998.
3
4
Ovassapian A, Krejcie TC, Joshi CN.
Fiberoptic vs rigid laryngoscopy for
rapid sequence intubation of trachea.
Anesthesia and Analgesia 1992; 74: S229.
Asai T. Use of the laryngeal mask
airway for fibrescope-aided tracheal in
an awake patient with a deviated larynx.
Acta Anaesthesiologica Scandinavica 1994;
Figure 6 Lateral cervical radiograph showing an apparent retropharyngeal mass
displacing the upper airway anteriorly at the level of the glottic inlet.
3
8: 615±16.
5
6
DeLellis RA. Thyroid gland. In: Cotran
RS, Kumar V, Robbins VL, eds.
Pathologic Basis of Disease, 4th edn.
Philadelphia: W.B. Saunders, 1989:
1228±9.
Mason RA. The obstructed airway in
head and neck surgery. Anaesthesia
1999; 54: 625±8.
Acute respiratory failure
secondary to severe
hypokalaemia
A recent case report by Dunn et al.
claimed to be the first reported case of
acute, respiratory failure due to hypo-
kalaemia requiring positive pressure
ventilation [1]. We also have had a
patient who developed acute respiratory
failure requiring ventilation secondary
to severe hypokalaemia.
A 57-year-old man with a 5-week
history of deteriorating health and
diarrhoea presented as an emergency
Figure 7 Non-enhanced axial computed tomogram section at the level of the glottis, with abdominal distension and shortness
showing a bilaterally enlarged thyroid gland insinuating between oesophagus and larynx. of breath. Prior to this episode, although a
This led to compression and narrowing of the upper airway at the level of the glottis and life-long smoker, he was active and had no
subglottis.
previous chest problems. On examination,
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Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
he was distressed, peripherally cyanosed hypokalaemia was precipitated by his factor in other causes of respiratory
and his abdomen was grossly distended diarrhoea and may have been exacer- failure so warrants prompt recognition
but soft. On admission, blood gas analysis bated by his lifestyle and diet. The and treatment in patients with incipient
showed a mixed picture of both metabolic combination of hypokalaemia and high respiratory failure.
alkalosis and respiratory acidosis: pH 7.42, plasma bicarbonate is more likely to
Pco2 11.9 kPa, Po 6.74 kPa, HCO3 have been due to potassium depletion,
B. R. Puddy
2
21
Royal Oldham Hospital,
Oldham OL1 2JH, UK
E-mail: bernard.puddy@oldham-
tr.nwest.nhs.uk.
52.7 mmol.l , BE 1 27.5 on 100% which is common, than due to a
oxygen. Serum electrolytes were potassium primary metabolic alkalosis, which is
2
1
21
1.26 mmol.l
,
sodium 147 mmol.l
rare [2]. The metabolic respiratory
21
and chloride 87 mmol.l . His ECG muscle function and metabolic alkalosis
showed changes consistent with hypo- both corrected following the adminis-
kalaemia. An abdominal X-ray showed tration of potassium. The original
a distended large bowel. A working assumption that he had chronic respira-
diagnosis of sigmoid volvulus was made tory failure with a compensatory alka-
and his respiratory failure attributed to losis proved not to be correct as his
an exacerbation of chronic obstructive blood gases returned to normal by the
References
Dunn SR, Famsworth TA,
1
2
Karunartatne WU. Hypokalaemic,
hyperchloraemic metabolic acidosis
requiring ventilation. Anaesthesia 1999;
pulmonary disease (COPD).
A flatus tube was passed with a good
time of discharge from the ICU.
It is recognised that hypokalaemia can
5
4: 566±7.
Zilva J, Pannall P. Clinical Chemistry in
Diagnosis and Treatment. London: Lloyd-
Luke (Medical Books), 1984.
result but his general condition and his produce muscular weakness and respira-
respiratory function continued to deter- tory insufficiency. Despite this widely
iorate and he was admitted to the held view, the case report of Dunn et al.
intensive care unit (ICU) for ventilation appears to be the first that describes 3 Holler JW. Potassium deficiency
3
h after arrival in hospital. Blood gases at the use of positive pressure ventilation
occurring during the treatment of
diabetic acidosis. Journal of the American
Medical Association 1946; 313: 1186±8.
that time were pH 7.1, Pco 27.52 kPa, in such circumstances. We were also
Po2 9.0 kPa, HCO 52.7 mmol.l
BE 1 24.1 mmol.l
2
21
,
unable to identify any other reported
cases. We were, however, able to find a
He was resuscitated with a mixture of case where negative pressure ventilation
3
21
.
crystalloid and colloid intravenous infu- in an iron lung was used to treat Operative tumour handling and
sions and initially required a small dose respiratory failure precipitated by insulin hyperkalaemia
of epinephrine to maintain his blood therapy in the treatment of a patient in a
pressure. He received 600 mmol of diabetic coma. The patient was treated Carvalho recently described a case of
potassium over the following 24 h by with potassium after which respiratory postoperative hyperkalaemia attributed
which time the serum potassium had function improved. In this case, it was to rapid blood transfusion [1]. The
returned to the normal range. Follow- assumed, but not proven, that the respira- mechanism was contested by Horsey,
ing ventilation, the gas exchange was tory failure was due to hypokalaemia [3].
significantly improved and his respira-
Why has it not been reported Anaesthesia 2000; 55: 294). A possible
tory acidosis corrected: pH 7.54, P co2 previously? It may be that it is not cause suggested by Carvalho is operative
but no alternative offered (Horsey.
a
5
.52 kPa, Pao2 12.22 kPa (Fio2 0.4) appreciated that the hypokalaemia is the tumour handling. We recently treated a
but a significant metabolic alkalosis cause of respiratory failure and an patient for postoperative hyperkalaemia
persisted: BE 1 13.6.
alternative diagnosis made. In our case, which we attributed to tumour hand-
The patient continued to receive respiratory failure was originally attrib- ling.
00 mmol potassium daily. With this uted to an exacerbation of COPD based The patient was a 70-year-old 96-kg
2
therapy, the metabolic alkalosis slowly upon a history of smoking and raised male admitted to the intensive care unit
resolved. He was extubated on the 4th serum bicarbonate. Interestingly, the treat- (ICU) after an emergency splenectomy
day of admission. He remained a further ment given for this condition, furosemide for intraperitoneal bleeding. He had a
3 days on the intensive care unit. At and steroids, may have exacerbated the history of axillary nerve sheath sarcoma
discharge, his blood gases on 50% hypokalaemia. In Holler's case, the patient with secondary metastatic deposits in
oxygen were: pH 7.43 Pco 5.08 kPa, was moribund with severe diabetic ketoa- the liver, lungs and spleen. Whilst an
2
21
,
Po2 10.4 kPa, HCO3 24.9 mmol.l
cidotic coma. Alternatively, it may require inpatient undergoing investigations, he
BE 0.4. The patient's abdomen an additional factor, in our case a grossly suddenly developed lower left chest
remained distended and he subsequently distended abdomen, such that the muscle pain, shortness of breath and dizziness.
underwent a laparotomy and colostomy weakness is sufficient to precipitate respira- On examination he was hypotensive
for a chronic sigmoid volvulus from which tory failure.
he made an unremarkable recovery.
Clearly, hypokalaemia may cause acute rate (72 beat.min ). Therapy included
(70/45 mmHg) with a normal heart
2
1
We believe this man's respiratory respiratory failure requiring mechanical 500 ml of intravenous colloid, which
failure was primarily due to hypokalae- ventilation. Conversely, hypokalaemic raised his blood pressure back to his
21
mic respiratory muscle weakness. The muscle weakness may be a contributory normal, and oxygen (6 l.min ) by face
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Anaesthesia, 2000, 55, pages 1213±1235
Correspondence
.
...............................................................................................................................................................................................................................................
mask. An arterial blood gas sample transfusion large or rapid enough to be dose of 200 mg. Following loss of
showed pH 7.34, P o 15.8 kPa, P co a likely cause. He did show evidence eyelash reflex, rocuronium 30 mg was
.2 kPa, bicarbonate 17 mmol.l and of impairment of renal function, but administered and manual ventilation
base excess 2 7.5. Serum biochemistry insufficient to produce such profound commenced. Shortly after rocuronium
a
2
a
2
21
4
21
revealed sodium 132 mmol.l , potas- hyperkalaemia. In addition, there was administration, the patient developed
21
21
sium 4.1 mmol.l , urea 4.9 mmol.l
no history of previous, nor subsequent, bronchospasm, hypotension and tachy-
and creatinine 79 mmol.l . His haemo- electrolyte disturbances to suggest an cardia leading to electromechanical
2l
2
1
globin had decreased from 10.2 g.dl
2
endocrine cause. We postulated that dissociation. The patient was resusci-
over 6 days. Urgent manipulation of friable sarcomatous tated with epinephrine 0.3 mg given
l
to 7.9 g.dl
abdominal ultrasound demonstrated an deposits may have released sufficient intravenously and intravenous fluids
extensive collection of free fluid within potassium to produce the hyperkalae- (1500 ml) and the total duration of
the abdomen, which was found to be mia. It is interesting to note that other circulatory arrest was approximately
heavily bloodstained on aspiration. reports of peri-operative hyperkalaemia 2 min. Surgery was abandoned and,
Findings at laparotomy included bleed- have also followed resection of sarcomas following the return of spontaneous
ing from a ruptured splenic metastasis [1±3]. This may simply be an associa- circulation, the patient was transferred
and multiple friable intraperitoneal sec- tion between vascular tumours where to the intensive care unit where he
ondary deposits. He underwent sple- resection often leads to the requirement was extubated 1 h later. He made an
nectomy with debulking of peritoneal for rapid transfusion, or maybe that a uneventful recovery from this episode.
secondary deposits. Blood loss was subgroup of these tumours have the
Blood and urine samples obtained
estimated at 1950 ml, for which he potential to cause sudden release of at 1, 6 and 24 h after the reaction
received 2 l of 0.9% saline and three potassium when stimulated by drugs or demonstrated elevations in mast cell
units (roughly 825 ml) of red cells over manipulation.
a period of 1.5 h. He remained haemo-
H. A. McLure
tryptase and urinary methylhistamine
in keeping with an anaphylactic/ana-
phylactoid reaction. Skin prick testing
demonstrated a positive reaction to rocur-
onium (20 mm  20 mm skin wheal)
at a 1 : 10 dilution.
dynamically stable throughout.
Royal Marsden Hospital,
London SW3 6JJ, UK
Postoperatively, he was transferred to
the ICU, where he was stable, mechani-
cally ventilated and producing adequate
volumes of urine. Arterial blood gas
sampling showed good gas exchange
with a metabolic acidosis (base excess
Our second case occurred in a 21-
year-old ASA II female presenting for
repair of an ostium secundum atrial
septal defect. She had no other past
medical history and had never had
a general anaesthetic. Induction was
achieved with remifentanil infusion at
References
1
2
Carvalho B, Quiney NF. `Near-miss'
hyperkalaemic cardiac arrest associated
with rapid blood transfusion.
Anaesthesia 1999; 54: 1094±6.
Krikken-Hoegenberk LG, de Jong JR,
Bovill JG. Succinylcholine-induced
hyperkalaemia in a patient with
metastatic rhabdomyosarcoma.
Anesthesiology 1989; 70: 553±5.
21
2
Laboratory analysis confirmed the
5.4) and a potassium of 7.8 mmol.l
.
2
1
hyperkalaemia of 7.5 mmol.l
showed normal sodium 134 mmol.l
, and
2
1
,
and creatinine
21
21
21
urea 6.3 mmol.l
135 mmol.l . The hyperkalaemia was
1 mg.kg .min and a target-controlled
infusion of propofol with a target con-
21
21
treated with intravenous 10% calcium
gluconate (10 ml), two infusions of 50%
centration of 3 mg ml . Following loss
of consciousness, rocuronium 50 mg
dextrose (50 ml) each with 15 iu insulin, 3 Chen CH, Hong CL, Kau YC, Lee BL, was administered. One minute later,
and per rectum calcium resonium (30 g).
Serial potassium measurements showed a
Chen CK, Shyr ME. Fatal
the patient coughed and became diffi-
cult to ventilate manually, a narrow
21
complex tachycardia of 165 beat.min
developed, the arterial pressure tracing
became non-pulsatile and the patient
developed florid generalised erythema
with urticaria. The trachea was intu-
bated and ventilation continued with
100% oxygen along with chest compres-
hyperkalaemia during massive blood
transfusion in a child undergoing hip
surgery ± a case report. Acta
21
decrease to 6.4 mmol.l after 6 h, then
4.7 mmol.l 24 h after admission. Serum
2l
creatinine kinase, calcium, phosphate and
urate were normal throughout. His renal
function deteriorated over the first 48 h
Anaesthesiology Sinica 1999; 37: 163±6.
21
with peak values of urea 14 mmol.l and Anaphylaxis to rocuronium
2
1
creatinine 205 mmol.l , subsequently
returning to normal over the next 24 h. We would like to report two cases of sions. Epinephrine (total dose 2.5 mg),
Extubation was delayed due to abdominal anaphylaxis to rocuronium bromide.
intravenous fluids (total volume of
distension compromising respiratory func-
The first reaction occurred in a 66- 2500 ml, a mixture of colloid and crystal-
tion, but he was successfully extubated on year-old ASA III male smoker sched- loid) and incremental doses of norepi-
the third day and discharged from the uled for mediastinoscopy for investi- nephrine up to 200 mg were given with
ICU on the fifth.
gation of a left hilar mass. Previous no effect. Second-line management con-
The reason for the hyperkalaemia general anaesthetics had been unevent- tinued with hydrocortisone 500 mg, neb-
remains unclear. He had not received ful. Anaesthesia was induced with ulised salbutamol 5 mg and ranitidine
succinylcholine, nor was the blood alfentanil 1 mg and propofol to a total 50 mg.
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Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
In view of the lack of response to our
S. J. Allen
A. Gallagher
L. D. Paxton
Royal Victoria Hospital,
Belfast BT12 6BA, UK
not changed over the last 50 years.
Ischaemic heart disease and hypertension
are considered to be associated with
operative risk. Having said that, Goldman
did not include hypertension as one of
the independent risk factors in his famous
pre-operative cardiac risk factors in non-
cardiac surgery. Pre-operative manage-
ment of hypertension has swung from
one extreme to another. With the advent
initial therapy, we proceeded to sterno-
tomy in order to perform internal
cardiac massage. At no point prior to
commencement of cardiopulmonary
bypass (33 min after the arrest) was an
external pulse palpable and the arterial
line continued to register a non-pulsatile
References
pressure. Surgery proceeded uneventfully 1 Ring J, Messmer K. Incidence and
and the patient was weaned from bypass
with relative ease.
The postoperative period was com-
severity of anaphylactoid reactions to
colloid volume substitutes. Lancet 1977; of antihypertensive drug therapy in
26: 466±9.
the early 1950s and the introduction of
potent antihypertensive drugs, such as
methyl dopa and guanethidine, fears were
expressed that cardiovascular homeostasis
would be adversely affected during anaes-
plicated by coagulopathy, airway and 2 Fisher MM, Baldo BA. Anaphylactoid
facial oedema and haemothorax, all of
which responded to appropriate ther-
apy. She made a full recovery and was 3 Neal SMcD, Manthri PR, Gadiyar V,
reactions during anaesthesia. Clinics in
Anaesthesiology 1984; 3: 677±92.
discharged 9 days later. Mast cell tryp-
tase and urinary methylhistamine were
elevated in keeping with an anaphylactic
reaction. Skin prick testing to rocur-
onium 6 weeks later was strongly posi-
Wildsmith JAW. Histaminoid reactions thesia and surgery. Thus, it was com-
associated with anaesthesia. British
monly proposed that antihypertensive
Journal of Anaesthesia 2000; 84: 108±11. therapy should be withdrawn prior to
elective surgery [3]. In fact, Goldman and
Caldera [4] suggested that elective surgery
tive (30 mm  30 mm) at a 1 : 10 Isolated systolic hypertension
dilution. In addition, skin prick testing and anaesthesia
for vecuronium produced a positive
in the absence of ideal antihypertensive
control need not subject patients to an
added clinical risk provided DBP is stable,
response (20 mm  20 mm).
Do we need to change the diagnostic not higher than 110 mmHg and peri-
Both of these cases demonstrated criteria for hypertension in our prac- operative blood pressures are closely
grade IV anaphylaxis (Ring and Mess- tice? In two separate articles, Poulter [1] monitored and treated to prevent
mer Scale [1]) and also met Fisher and and Wilkinson [2] identified the impor- hypertensive or hypotensive episodes.
Baldo's criteria for an anaphylactic tance of isolated systolic hypertension
The postponement of scheduled sur-
reaction [2]. We present these cases to (ISH) as a significant predictor of future gery because of incidentally discovered
highlight the fact that although rocur- cardiac morbidity and mortality. The mild to moderate hypertension causes
onium causes little or no direct British Hypertension Society (BHS) also inconvenience to patients and doctors,
histamine release, it can cause recommended, in recently published as well as hospital management. Ade-
immunologically-mediated histamine guidelines, drug therapy in people with quate blood pressure control may take
release or anaphylaxis. The frequency sustained systolic blood pressure (SBP) weeks, if not months, to achieve. At the
with which these reactions are occur- greater than or equal to 160 mmHg, same time, the foregoing data, which
ring is giving cause for concern. Neale and the decision to treat sustained suggest beyond doubt that ISH is a
et al. in their recent report suggest a SBP between 140 and 159 mmHg to definitive risk factor for cardiac mor-
crude incidence of reaction of approxi- be made according to the presence or bidity and mortality in the community,
mately 1 : 3000 [3]. Based upon the absence of other risk factors. In his cannot be ignored. The million-pound
number of reactions and the number of article, Poulter referred to the Framing- question now is that should we, as peri-
vials used, our `hospital reaction rate' is ham data, which challenged the notion operative physicians, take this as a gospel
approximately 1 : 6000. The manufac- that diastolic blood pressure (DBP) fact? Or should we wait for more
turers estimate that the incidence is alone is chiefly responsible for the prospective randomised trials of pre-
approximately 1 : 200 000 worldwide cardiovascular sequelae of hypertension. operative blood pressure control of hyper-
(personal communication Organon- Compared with DBP, SBP correlates tensive patients to establish the effect of
Teknika).
more strongly with stroke, congestive anaesthesia and surgery on the outcome
The obvious conclusion is that heart failure, coronary artery disease, in these patients? The answer to the first
we do not have enough data to state declining renal function and left ventri- question is that we should, since we live
definitively the incidence of reaction. cular hypertrophy. According to the latest in the era of evidence-based medicine.
In view of this, it is important that we BHS guidelines, target blood pressure in Any inconvenience would certainly be
monitor the use of this drug closely non-diabetic patients should be 140/ justified if postponing surgical procedures
and ensure that any possible reactions 85 mmHg, and in patients with diabetes until hypertension has been controlled
are investigated appropriately and , 140/80 mmHg.
reported to the relevant agency to In anaesthetic practice, however, the plications. However, the answer is not as
facilitate the gathering of accurate attitude towards cardiac disease in gen- easy for the second question, as waiting
decreases the risk of peri-operative com-
adverse event data.
eral, and hypertension in particular, has may lead to more lives being put at risk.
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Correspondence
.
...............................................................................................................................................................................................................................................
M. Al-Khalid
Ysbyty Gwynedd,
Bangor LL57 2PW, UK
bougies were contaminated, most (14/ to decontaminate after use and protect
23) with less than 20 cfu, though one from subsequent recontamination.
bougie yielded 91 cfu. The mean and
N. Shah
median counts were 17 and 8, respec-
tively, with an interquartile range of
J. R. Greig
J. R. Stephenson
S. Jankowski
St Helier Hospital,
Carshalton SM5 1AA, UK
References
Poulter N. Isolated systolic
5±24. The majority of bacteria were
coagulase negative Staphylococci,
1
2
hypertension: clinical significance and
management. British Journal of
Cardiology 2000; 7: 149±51.
Micrococci, diphtheroids and Bacillus
sp. (Table 2). Of particular concern was
the growth of Proteus sp. from one bougie
tip and environmental gram-negative rods
from another nine. The latter included
members of the genus Pseudomonas and
Acinetobacter, which are potential nosoco-
mial pathogens and common causes of
ventilator-associated pneumonia [2].
The different rates of contamination
between our study and that of Cupitt
may be because, in the latter, many
bougies had been newly issued to the
wards and probably had been used
less often than the ones we sampled.
Ventilation and airway manipulation
Wilkinson I, Webb Christison D,
Cockroft J. Isolated systolic
References
1
2
Murray PR, Baron EJ, Pfaller MA,
Tenover FC, Yolken RH. Manual of
Clinical Microbiology 7th edn.
hypertension: a radical rethink. British
Journal of Medicine 2000; 320: 1685.
Prys-Roberts C. Hypertension and
anaesthesia-fifty years on. Anesthesiology
3
4
Washington, DC: American Society for
Microbiology, 1999.
1
979; 50: 281±4.
Strausbaugh LJ. Nosocomial respiratory
infections. In: Mandell GL, Bennett JE,
Dolin R. eds. Principles and Practice of
Infectious Diseases 5th edn. Philadelphia:
Churchill Livingstone, 1999: 3020±8.
Goldman L, Caldera D. Risks of general
anaesthesia and elective operation in the
hypertensive patient. Anesthesiologv
1
979; 50: 285±92.
Microbial contamination of
gum-elastic bougies
are recognised risk factors for hospital- Ventilator trigger setting in an
acquired pneumonia [2]. The introduction intensive care unit
We read Cupitt's study on microbial of microbial contaminated bougies may
contamination of gum elastic bougies be an additional risk for infection. The We read with interest the recent case
(
Cupitt. Anaesthesia 2000; 55: 466±8) majority of bacteria identified were of report `Brainstem death and ventilator
with interest and report a similar study
with further evidence that bougies may
be contaminated with potentially
pathogenic bacteria.
trigger settings' (Willatts & Drummond.
Anaesthesia 2000; 55: 676±7). We
regularly face the same technical pro-
blem in setting ventilators in mech-
anically-ventilated patients (Puritan
Bennett 7200 ventilator) with a left
ventricular assist device (LVAD) in our
cardiothoracic intensive care unit. The
LVAD is implanted in patients with
end-stage cardiac failure. In the LVAD
system, a diaphragm pump is fixed
intraperitoneally and is connected to
left ventricular cavity and aorta beyond
the aortic valve with preclotted, woven
Dacron graft [1]. The pump maintains
the cardiac output for the patient and it
creates enough negative intrathoracic
pressure to trigger the ventilator for
synchronised intermittent mandatory
ventilation (SIMV) or pressure support
ventilation if the set sensitivity is at its
most sensitive. The usual pressure below
PEEP trigger has been found to be the
cause of ventilator auto cycling, even
at relatively insensitive levels of 4 or
low virulence and are rarely associated
with infection but a significant minority
were potential pathogens. If bougies are
to be reused, autoclaving or efficient
cleaning and disinfection of bougies are
needed together with effective protection
from recontamination during storage.
As Cupitt notes, it may be safer and
more cost effective to use single-use
bougies only once, avoiding the need
Twenty-three single and multiple-use
autoclavable) gum elastic bougies from
(
resuscitation trolleys on medical and
surgical wards, the intensive care unit
and operating theatres were investigated
for bacterial contamination. The bougies
were stored unwrapped either in upright
uncovered holders attached to the side
of the trolley or in one of the trolley
drawers. After use, these bougies are ing bougie tips.
usually washed with soap and water and
dried before returning them to the
trolley. The bougie tip was sampled by
rubbing a moistened sterile swab across
it and directly inoculating Columbia
agar supplemented with horse blood.
Coagulase negative
After incubation for 48 h in a carbon-
dioxide-enriched atmosphere, the plates Aerobic gram-negative rods
were examined and the number of Mixed growth*
bacterial colonies recorded as colony-
Table 2 Identities of bacteria contaminat-
Bacteria
No. of
isolated
contaminated
bougie tips
4
staphylococcus/Micrococcus
2
15
2
No growth
forming units (cfu). Standard microbio-
logical techniques were used to identify
the bacteria to at least genus level [1].
5 cmH O; this with the patient
2
*
Includes mixtures of coagulase negative
staphylococci, diphtheroids, Bacillus sp. aero- apnoeic on disconnection of the circuit.
Twenty-one of the 23 sampled bic gram negative rods and Proteus sp.
Obviously, this will add to the work of
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Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
breathing and make weaning from IPPV complications, which include haematoma,
gradient effect. Critical Care Medicine
difficult when the time comes.
distal ischaemia, emboli, local infection and
1998; 26: 1623±4.
We have found flow triggering to be catheter-associated bacteraemia [2]. The 6 Stern DH, Gerson JI, Allen FB, Parker
the answer in these circumstances using carotid is not considered for arterial
the flow-by function on the Puritan pressure measurement because the con-
Bennett 7200. An average base flow sequences of embolisation from the
FB. Can we trust the direct radial artery
pressure immediately following
cardiopulmonary bypass? Anesthesiology
1985; 62: 557±61.
2
1
of 20 l.min
3
and trigger setting of catheter or arterial occlusion may be
l.min are generally suitable. We have devastating. Clearly, in the setting of
2
1
found this demonstration of apnoea on brainstem death, cerebrovascular acci-
disconnection of the ventilator circuit dent is no longer a concern and the
plus the elimination of `auto-cycling' carotid artery is an attractive alternative
with `flow-by' has reassured all intensive to more conventional sites.
Preparation of anaesthetic
drugs in the obstetric theatre
care staff of the true state of the patient
regarding spontaneous inspiratory effort.
In health, as one moves distally
through the arterial tree, mean pressure
remains constant, yet pulse pressure
increases [3]. However, radial artery
lines may yield a falsely low reading
in patients receiving high doses of
vasopressor [4, 5] and following CPB
I read with interest the letter by J. M.
Cupitt and C. Dunkley (Cupitt &
Dunkley. Anaesthesia 2000; 55: 721).
Following a recent Health and Safety
Review we also had to address the
problem of providing obstetric emergency
drugs safely.
M. Haldar
J. Farrimond
Harefield Hospital,
Harefield UB9 6JH, UK
[
6]. Therefore, in the setting of organ
We felt we would be putting patient
safety at risk were we to stop having
thiopental and succinylcholine immedi-
ately available. Genuine `crash sections'
are few and far between; however,
when they occur, time is extremely
precious and many urgent tasks need to
be performed by the obstetric and
anaesthetic team. Preparing anaesthetic
drugs in this situation would either take
up the anaesthetist's time when this can
be ill afforded or might have to be
delegated; the risk of preparation errors
must be higher in these circumstances.
Therefore, we continue to draw up
thiopental and succinylcholine (no other
drugs) daily, and keep them capped and
labelled with date, time, concentration
and initials in the refrigerator. A minijet
syringe of atropine is kept with them.
To keep the drugs tamperproof in a
locked refrigerator could of course
prevent immediate availability. Since
the chief purpose of the lock is to
prevent tampering not theft, we now
apply a numbered plastic lock, which is
recorded in a logbook. The preparation
time of the drugs is also logged. It only
takes seconds to check the integrity
of the tag and compare the number
against the log, and we still have access
to the essential drugs to induce general
harvest, monitoring pressure in the
carotid artery pressure may be superior
to the radial artery.
Reference
1
Frazier OH. Chronic left ventricular
support with a vented electric assist
device. Annals of Thoracic Surgery 1993;
P. Sutherland
5
5: 273±5.
Southampton General Hospital,
Southampton SO16 6YD, UK
E-mail: PaulDSutherland@
Hotmail.com
Use of a carotid arterial line
during organ harvest
To protect the function of organs
harvested from patients who have
satisfied the criteria for brainstem
death, careful physiological support of
the donor is required. Prolonged hypo-
tension is associated with decreased
allograft survival [1]. Organ harvest
causes large insensible fluid loss and
blood loss may be significant. To
optimise fluid replacement and inotrope
therapy, invasive blood pressure moni-
toring is mandatory.
References
Mackersie RC, Bronsther OL,
1
2
Shackford SR. Organ procurement in
patients with fatal head injuries. The
fate of the potential donor. Annals of
Surgery 1991; 213: 143±50.
Russell RA, Mannie J, Hudson RJ,
Mangano DT, Schlobohm RM.
Prospective evaluation of radial and
femoral artery catheterization sites in
critically ill patients. Critical Care
Medicine 1983; 11: 936±9.
Twice, I have anaesthetised inotrope-
dependent patients for organ harvest,
during which the radial artery line has
failed. As access to the arms, groins
and lower limbs was very difficult, on
both occasions I placed an 18-g Jelco
3
4
Hamilton WF, Dow P. An experimental
study of the standing waves in the pulse
propergated through the aorta. American
Journal of Physiology 1939; 125: 48±59.
Dorman T, Breslow MJ, Lipsett PA,
Rosenberg JM. Radial artery pressure
monitoring underestimates central
arterial pressure during vasopressor
(Johnson and Johnson Medical) into the
left carotid artery. This was straight-
forward and allowed transduction of
arterial blood pressure.
therapy in critically ill surgical patients. anaesthesia in an emergency section.
Invasive arterial monitoring is tradi-
tionally performed in the radial, femoral, 5 Hynson JM, Katz JA, Mangano DT.
axillary or brachial arteries. The choice
of site is determined by the profile of
Critical Care Medicine 1998; 26: 1646±9.
In time, we hope to obtain premade
syringes of thiopental and succinylcho-
line from our pharmacy department,
which would add a further degree of
On the accuracy of intra±arterial
pressure measurement. The pressure
1226
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Anaesthesia, 2000, 55, pages 1213±1235
Correspondence
.
...............................................................................................................................................................................................................................................
safety. Meanwhile, we feel we have struck conclusions can be drawn about the
an acceptable risk±benefit balance.
As regards Dr Low's comment on
effects of epidural analgesia as compared volume status, all patients had pre-
to systemic morphine on splanchnic operative fluid resuscitation and those
C. E. Calow
Burnley General Hospital,
Burnley BB10 2PQ, UK
perfusion.
receiving epidurals had a further 500±
50 ml of crystalloid whilst the block
7
J. Low
Milton Keynes General Hospital,
Milton Keynes, UK
E-mail: ccp@dialstart.net
was being established. Central venous
and invasive arterial pressures were
measured peroperatively in all patients.
Comparison of mean arterial pressure
between the epidural and opiate groups
showed no significant differences over
the course of the procedure (data yet to
be published). We feel that adequate
hydration was maintained peroperatively
in both groups and that our conclusion
that there was no tonometric difference
in splanchnic perfusion is still valid.
Epidural anaesthesia and
splanchnic blood flow
References
Several points in the recent article about
the effect of epidural bupivacaine on 1 Nydahl PA, Philipson L, Axelsson K,
splanchnic blood flow (Mallinder et al.
Anaesthesia 2000; 55: 659±65) are
worth highlighting. The initial power
calculation estimated that 40 patients
Johannsson JE. Epidural anesthesia with
0.5% bupivacame: influence of age on
sensory and motor block. Anesthesia and
Analgesia 1991; 73: 780±6.
would be required but only 32 were 2 Hogan QR, Stekiel TA, Stadnicka A,
P. A. Mallinder
Darlington Memorial Hospital,
Darlington DL3 6HX, UK
analysed. All the patients lost from the
study were from the epidural group (12
vs. 20) making comparisons difficult.
There were also many more patients
Bosnjak ZJ, Kampine JP. Region of
epidural blockade determines sympathetic
and mesenteric capacitance effects in
rabbits. Anesthesiology 1995; 83: 604±10.
J. E. Hall
University Hospital of Wales,
Cardiff CF14 4XW, UK
who were ASA 3 in the morphine 3 Lundberg J, Lundberg D, Norgren L,
group than in the epidural group (8 vs.
). I note that 44% of the total group
Ribbe E, Thorne J, Werner O.
Intestinal hemodynamics during
2
F. G. Bergin
P. Royle
D. J. Leaper
North Tees Hospital,
Stockton-on Tees, UK
suffered complications, ranging from
wound infection to death, which
seems excessively high.
laparotomy. Effects of thoracic epidural
anesthesia and dopamine in humans.
Anesthesia and Analgesia 1990; 71: 9±15.
The authors acknowledged that it
was possible that the epidural catheters
were sited too low to achieve adequate A reply
sympathetic blockade, but countered We thank Dr Low for his interest in our
this by suggesting that the large volumes recent article. We acknowledged in our
Reference
of local anaesthetic used and the fact article that due to unforeseen losses of 1 Nydahl PA, Philipson L, Axelsson K,
that patients were all comfortable post- patient data the power of our study was
operatively indicated an adequate der- decreased from the projected 0.9 to 0.7.
Jojansson JE. Epidural anesthesia with
0.5% bupivacaine: Influence of age on
sensory and motor block. Anesthesia and
Analgesia 1991; 73: 780±6.
matomal level of analgesia. The solution
Although the solution used in
used in the study has not been validated Nydahl's experimental study [1] was
to produce sympathetic blockade to T5 0.5% bupivacaine as opposed to the
with a lumbar epidural catheter [1]. 0.25% used by us, it is well known that
Patients would only require a dermatomal it is mainly the volume of anaesthetic Pregnancy, anaesthesia and
analgesia level of T to be comfortable and not the concentration that influ- Guillain±Barre syndrome
8
intra- and postoperatively, far below the ences the height of sensory blockade. In
level required for sympathetic blockade of Nydahl's study, the median maximal I was interested to read the case report
the mesenteric vessels [2]. At no point in cephalad spread of analgesia after epi- of Guillian Barre syndrome (GBS) in
the paper did they discuss blood pressure dural injection of 20 ml of 0.5% pregnancy (Brooks et al. Anaesthesia
changes or the amount or type of bupivacaine in supine patients of a 2000; 55: 894±8). I would like to add
intravenous fluid used to correct hypo- similar age group was T . It is therefore additional information arising from
4
tension. It is well documented that a reasonable assumption that the intra- experience with a similar patient. This
epidural-induced hypotension can cause operative spread of 20 ml of 0.25% highlights the importance of gestational
gut hypoperfusion [3]. If an adequate bupivacaine would cover most of the age during the illness, and also of
sympathetic blockade to T was achieved splanchnic sympathetic outflow (T to attempting to define a precipitating
5
5
with the initial bolus, especially in this T ). With regular top ups peropera- cause for the illness.
11
group of surgical patients, some degree tively, most patients had excellent
of hypotension must have occurred.
analgesia in recovery with blocks from sented with a rapidly evolving GBS
It would seem unlikely, given the T to T (though not specifically stated 1 week after an episode of pharyngitis.
A previously well 19-year-old pre-
5
8
combination of the above factors, that in our article).
Lumbar puncture and nerve conduction
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Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
studies confirmed the diagnosis. Sero-
logical testing was positive for CMV 1 Hahn A. Guillain±Barre Syndrome.
IgM antibodies in a dilution of 1 : 512,
indicating recent Cytomegalovirus
(CMV) infection. Other relevant serol-
ogy was negative.
References
factor (vWF). In type I VWD there is a
reduction in the amount of vWF in the
blood, in type 2 VWD normal levels of
vWF are found but it is functionally
abnormal, and in type 3 VWD there is a
severe deficiency in levels of vWF. VWF
is required for platelet adhesion to
damaged endothelium during the for-
mation of the platelet plug. It is also the
carrier protein for factor VIII. Defi-
ciency of vWF leads to prolonged
bleeding times and patients usually
present with abnormal bleeding condi-
tions such as menorrhagia or epistaxis
The haematological investigations are
used in VWD to determine both the
quantity and functional capacity of vWF
in the patient's plasma. The amount of
vWF is determined by measuring the
vWF:Ag level, whereas the Ricof level
is a measure of its functional activity.
The vWF:Ag level in the plasma can be
assayed directly and compared to a
reference curve of standard dilutions so
that a level . 50% is normal. Ricof
levels are determined by adding a
sample of the patient's plasma to
normal platelets and then adding the
antibiotic ristocetin. Ristocetin reacts
with vWF and the platelet membrane to
induce platelet aggregation. This inter-
action requires the presence of a func-
tional unit of the vWF known as the
ristocetin cofactor. Ristocetin-induced
aggregation follows a dose±response
curve dependent upon the amount of
functional vWF present. Thus, a `normal'
Ricof level is quoted as . 50%. Ristoce-
tin does not agglutinate the platelets in
many patients with VWD due to the
absence of the ristocetin cofactor. Thus in
Lancet 1998; 352: 635±41.
2
3
4
Stagno S, Whitley RJ. Herpesvirus
infections of Pregnancy. Part I.
Cytomegalovirus and Epstein-Barr
virus infections. New England Journal of
Medicine 1985; 313: 1270±4.
Treatment with intravenous immuno-
globulin (IvIG) was started immediately
on admission to hospital. By day 2 of her
illness, she required mechanical ventila-
tion for respiratory insufficiency. Despite
marked autonomic dysequilibrium, a
general anaesthetic was administered
uneventfully on day 7 for insertion of a
tracheostomy. Her illness reached a nadir
at around 10 days when she exhibited a
dense quadriparesis and retained only
minimal motor function of her extra-
ocular muscles. Three weeks following
ICU admission, a pregnancy test was per-
formed because of amenorrhoea. It was
positive and ultrasonography suggested a
fetal age of 9 weeks. In view of her
severity of illness, gestational age and
CMV status, she elected for termination
of pregnancy. This was carried out under
Simor AE, Ferro S. Campylobacter
jejuni infection occurring during
pregnancy. European Journal of Clinical
Microbiology & Infectious Diseases 1990; 9:
142±4.
Freij BJ, Sever JL. Herpes virus
infections in pregnancy: risks to
embryo, fetus, and neonate. Clinics in
Perinatology 1988; 15: 203±31.
Von Willebrand's disease and
neuroaxial anaesthesia
We would like to report the case of a
3-year-old primigravida woman with
2
von Willebrand's disease (VWD). Our
local consultant haematologist notified
us of her when she was 36 weeks
gestation. Apart from her von Will-
ebrand's disease she was apparently fit
and healthy and was enjoying an
uncomplicated pregnancy. Her labora-
tory results were as follows: von Will-
ebrand factor antigen (vWF:Ag) 28%
and Ricof level 42%. On the basis of
these results, the haematologist sug-
gested that an experienced anaesthetist
could perform epidural analgesia safely
as her risk of bleeding into the epidural
space was minimal. We, along with our
colleagues, were not sure of the validity
of this advice and were unfamiliar with
(another uneventful) general anaesthetic.
After 86 days in the intensive care unit,
the patient was discharged for further
care. Her recovery was slow and compli-
cated, but eventually of a good quality.
This case adds to the information
provided by Brooks et al. CMV is
causally implicated in 10±22% of GBS
[1]. It is a serious infection in the first
trimester: 5% of infected babies will
have early multiple disabilities and a
further 5% develop later handicaps [2].
These include microcephaly, mental
retardation and motor disorders.
Other triggers associated with GBS
e.g. Epstein±Barr virus, Varicella zoster
(
these laboratory results. We therefore VWD the Ricof level is often reduced. If
decided to determine the significance of the Ricof level is above 30% the risk of
the haematological investigations per- bleeding is not thought to be increased;
formed in patients with VWD and however, when below this level, especially
clarify the risk of bleeding associated if the level is , 10%, there is a significant
with regional analgesia. We felt that risk of bleeding.
virus, HIV, Campylobacter jejuni [1]) may
also have implications for the mother
and fetus. These range from trivial to
include congenital varicella, sepsis and
fetal death [2±4]. Consequently, for all
patients with GBS who may be preg-
nant, a thorough search for potential
causes should be carried out, since the
results may have significant consequences
for the management of both patients.
anaesthetists need to be aware of this
There does not seem to be any
disease and have an understanding of consensus on the Ricof level that is safe
how it is investigated in order to make for regional anaesthesia (Giangrande
valued judgements in the use of regional PLF, Oxford Haemophilia Centre, per-
techniques in the presence of possible sonal communication). We could only
I. Nesbitt
abnormal haemostasis.
find one case report in the literature that
Freeman Road Hospital,
Newcastle upon Tyne NE7 7DN,
UK
Von Willebrand's disease is an inher- described the use of an epidural in a
ited haematological disorder where patient with VWD. This obstetric
there is a deficiency of von Willebrand's patient had a Ricof level of 10% and
1228
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Correspondence
.
...............................................................................................................................................................................................................................................
vWFAg level of 35%. The use of an Probably, the pharmacokinetics of intra-
epidural was uneventful [1].
Aly and Shilling suggested that fen-
muscular administration are not ideal tanyl could be administered via an
Fortunately, our patient had an for the intermittent pain of labour. An intravenous PCA device but said that
uneventful delivery and did not require opioid drug with a rapid onset and short no studies had been done. We would
our assistance. However, as a precaution half-life (such as fentanyl) delivered by like to draw attention to the study
we arranged for desmopressin to be PCA is better suited to labour pain. performed by Nikkola et al. [3] in
available on the delivery suite in the However, PCA is not available to which fentanyl PCA was compared to
event of a postpartum haemorrhage millions of labouring women in devel- epidural analgesia. This study, whilst
(
PPH). Women with VWD are at oping countries, where pethidine may suffering from a number of design faults,
increased risk of PPH as the level of be the best available analgesic drug.
showed that fentanyl PCA is a poor
vWF falls rapidly following delivery.
I agree with the authors that multi- alternative to an epidural for labour
Desmopressin is used therapeutically centre trials should be conducted to analgesia.
to boost the level of vWF production identify effective narcotics, but this
The pharmacokinetic properties of
in vivo.
should not be limited to only three remifentanil make it a far more ideal
We would be interested to hear the drugs (morphine, diamorphine and fen- opioid for use in labour. Remifentanil is
experience of other anaesthetists in the tanyl) and should include other narcotics an opioid with an onset time equivalent
management of patients with VWD and which have unique pharmacokinetic to alfentanil but which is rapidly
at what Ricof level they regard regional (such as remifentanil) and pharmacody- metabolised by blood and tissue non-
anaesthesia to be safe.
namic (such as tramadol) properties.
specific esterases. It is therefore non-
cumulative even when given over long
periods of time [4]. In contrast, fentanyl
has a context-sensitive half time that
increases with the duration of adminis-
tration causing it to accumulate. It will
also cross the placenta and thus accu-
mulate in the fetus, potentially causing
neonatal respiratory depression or other
neurobehavioural changes. Remifenta-
nil, although it too crosses the placenta,
is rapidly metabolised by the fetus [5].
In one of our institutions, we have
J. C. Stedeford
J. A. L. Pittman
Gloucestershire Royal Hospital,
Gloucester GL1 3NN, UK
J. S. Anwari
Riyadh Armed Forces Hospital,
C-151, PO Box no. 7897,
Riyadh 11159, Saudi Arabia
E-mail: janwari@hotmail.com
Reference
1
Milaskiewicz RM, Holdcroft A, Letsky
E. Epidural anaesthesia and Von
Willebrand's disease. Anaesthesia 1990;
Parenteral narcotic analgesic
for labour pain 2
4
5: 462±4.
We read with interest the editorial by used remifentanil PCA for certain
Drs Aly and Shilling (Aly & Shilling. parturients in whom epidural analgesia
Anaesthesia 2000; 55: 419±20) in which is contraindicated [6]. In the other, we
they discuss the reasons for the con- have studied nine women who have
tinuing use of intramuscular pethidine received a remifentanil PCA with good
Parenteral narcotic analgesic
for labour pain
I read with interest the editorial `Are for relief of labour pain. However, we reduction in visual analogue pain scores
we willing to change?' (Aly & Shilling. wish to challenge the suggestion and no adverse effects to either mother
Anaesthesia 2000; 55: 419±20), which that fentanyl administered as intrave- or neonate (Volikas and Male, unpub-
discusses four narcotic analgesics admi- nous patient-controlled analgesia (PCA) lished data). These women did not have
nistered parenterally for labour pain. I should replace pethidine.
any contraindications for an epidural
was surprised to read that pethidine
It has long been known that for up to other than a maternal wish to avoid an
does not act as an analgesic but works half of parturients, pethidine provides epidural if possible and would otherwise
only as a sedative. It is well known that either no or inadequate pain relief [1]. have received pethidine analgesia.
pethidine binds with m-receptors, In current midwifery practice it is often Unlike the current use of intramuscular
which modulate pain at spinal and administered in early labour to produce pethidine, which often provides seda-
supraspinal level and also induce seda- anxiolysis and sedation rather than tion without analgesia, the women are
tion. Pethidine has been effectively used analgesia. The reason that intramuscular able to use the PCA pump to attain a
for other types of visceral pain such as opioids do not produce reliable analge- mixture of analgesia or sedation that
that associated with gall bladder and sia is not related to the particular opioid they find acceptable.
renal colic. Conceivably, a patient is chosen, but that an insufficient dose is
We would accept that further studies
more likely to go to sleep under the given by an inefficient route. Scott, in should be performed formally to assess
analgesic effect of pethidine. The fact his original description of PCA in the efficacy of remifentanil PCA and its
that a labouring mother who has labour [2], quoted a mean pethidine effects on the neonate. However, this
received intramuscular pethidine wakes dose of 448 mg with a maximum dose drug would appear to offer the best
up due to labour pain does not mean of 1440 mg. These doses were very way forward in developments for non-
that the drug has no analgesic effect. effective.
epidural labour analgesia.
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Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
R. Jones
I. Volikas
R. G. W Stacey
D. Male
Kingston Hospital,
Kingston Upon Thames KT2 7QB,
UK
have included those studies in our
editorial.
References
1 Eastwood D, Williams C, Buchan I.
Caudal epidurals: the whoosh test.
Anaesthesia 1998; 53: 305±7.
Regarding the use of fentanyl or remi-
fentanil for labour analgesia, we think it is
too early to suggest either is superior over
the other and agree that further large
studies are needed to establish the efficacy
as well as the safety of these drugs.
2
Puddy BR. The `Whoosh' test.
Anaesthesia 1999; 54: 614.
3
Pither CE, Prthvi Raj P, Ford DJ. The
use of peripheral nerve stimulators for
regional anesthesia. A review of
experimental characteristics, technique
and applications. Regional Anesthesia
1985; 10: 49±58.
E. E. Aly
R. S. Shilling
Warwick Hospital,
Warwick, CV34 5BW, UK
References
1
2
Chamberlain G, Wraight A, Steer P.
Pain and its relief in childbirth. Report of
the 1990 NBT Survey. Edinburgh:
Churchill Livingstone, 1993.
Scott JS. Obstetric analgesia: a
consideration of labour pain and a
patient controlled techniques for its
relief with meperidine. American Journal
of Obstetrics and Gynecology 1970; 106:
References
Reducing the incidence of
1
2
Rosaeg OP, Kitts JB, Koren G, Byford technical failures and
LJ. Maternal and fetal effects of
intravenous patient-controlled fentanyl
analgesia during labour in a
paraesthesia in combined
spinal±epidural techniques
9
59±78.
thrombocytopenic parturient. Canadian
Journal of Anaesthesia 1992; 39: 277±81.
Nikkola EM, Eblad UU, Kero PO,
Alihanka JJM, Salonen MAO.
Recent studies have shown that the
combined spinal±epidural (CSE) tech-
nique is gaining in popularity for labour
analgesia in the UK, with 24% of
obstetric units offering CSEs in 1999
compared to none in 1991 [1]. The
disadvantages of the single interspace
needle-through-needle CSE technique
include high spinal component failure
rates due to spinal needle movement
3
4
Nikkola EM, Ekblad UU, Kero PO,
Alihanka JJM, Salonen MAO.
Intravenous fentanyl PCA during
labour. Canadian Journal of Anaesthesia
Intravenous fentanyl PCA during
labour. Canadian Journal of Anaesthesia
1
997; 44: 1248±55.
Egan TD, Lemmens HJM, Feset P et al.
The pharmacokinetics of the new
short-acting opioid remifentanil
1997; 44: 1248±55.
(
G187084B) in healthy adult male
volunteers. Anesthesiology 1993; 79:
81±92.
The safest prediction of
epidural analgesia
(10%) [2], and a high incidence of
8
paraesthesia (29%) reported in certain
studies [3].
5
6
Kan RE, Hughes SC, Rosen MA,
Kessin C, Preston PG, Lobo EP.
Intravenous remifentanil ± Placental
Transfer, Maternal and Neonatal Effects.
Anesthesiology 1998; 88: 1467±74.
Jones R, Pegrum A, Stacey RGW.
Patient-controlled analgesia using
remifentanil in the parturient with
thrombocytopenia. Anaesthesia 1999;
Drs Singh and Kahn (Singh & Khan.
Anaesthesia 2000; 55: 830±2) report the
use of a peripheral nerve stimulator after
the injection of bupivacaine into the
caudal epidural space as a predictor of
successful caudal epidural analgesia. In
their study, they performed whoosh
test-1 [1] but they failed to perform
whoosh test-2 [2]. Peripheral nerve
stimulation is most safely used prior to
the injection of local analgesic drugs [3],
and not after the injection as the current
required is much less. The use of a
peripheral nerve stimulator with high
current after the injection of local
analgesic drugs is unsafe and could
lead to neurological damage.
During the CSE procedure, the
removal of the inner spinal needle
stillette to confirm successful dural
puncture by visualisation of CSF at the
hub of the needle as well as subsequent
connection and injection of the intra-
thecal drug containing syringe are all
potential points at which excessive
spinal needle movement, and therefore
failure of the technique, may occur.
Paraesthesia, and potential neurological
problems, on the other hand, can be
elicited if the spinal needle is inserted
too far through the dural sac [4].
Although it is well known that a
maximum spinal needle protrusion dis-
tance of less than 15 mm (epidural
needle tip to spinal needle tip) with a
CSE can lead to increased failures by
inability to puncture the dura, there is
no consensus on the upper limits of the
protrusion distance. An excessively long
spinal needle such as the 26G, 124 mm
Gertie Marx pencil point needle can
5
4: 461±5.
A reply
We are grateful for the comments of
Dr Jones and colleagues. We were aware
of one case report by Rosaeg et al. [1] as
well as the study by Nikkola et al. [2]
that involved six patients. Both the case
report, as well as the study, showed
some benefit of using fentanyl patient-
controlled analgesia for pain relief in
labour. We felt it was not appropriate
to make a conclusion on the use of
fentanyl PCA for labour analgesia on
the basis of studies that included only
seven patients, but we admit we should
Whoosh test-2 confirmation of the
correct position of the needle is safe and
easy to perform and never produces
neurological damage.
B. R. Puddy
L. B. Cook
Royal Oldham Hospital,
Oldham OL1 2JH, UK
1230
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Correspondence
.
...............................................................................................................................................................................................................................................
therefore produce an unacceptable inci-
dence of paraesthesia (29%), presumably
due to its long maximum protrusion
A survey of epidural analgesia for labour flavum and consequently out of
in the United Kingdom. Anaesthesia
1999; 54: 634±40.
the epidural space. This may occur
immediately following placement if
the woman changes position, or more
distance, compared to the more com- 2 Collis RE, Baxandall ML,
monly used shorter 27G, 119 mm
Whitacre spinal needle [3].
Srikantharajah ID, Edge G, Kadim MY, gradually during the course of labour. It
Morgan BM. Combined spinal epidural is reasonable to assume that this is more
We believe that the following two
refinements of the existing CSE tech-
nique can potentially reduce the inci-
dence of both spinal injection failure
(CSE) analgesia: Technique,
management, and outcome of 300
likely in obese women in whom greater
movement of the skin relative to the
mothers. International Journal of Obstetric ligamentum flavum is possible [1].
Anesthesia 1994; 3: 75±81.
We should like to illustrate varying
degrees of such catheter movement
Newman LM. An in vivo evaluation of with cases investigated radiologically
and paraesthesia and so lead to improve- 3 Herbstman CH, Jaffee JB, Tuman KJ,
ments in success rates and safety.
Firstly, the inner stillette of the spinal
needle is removed [5], before slowly
advancing the spinal needle within the
four spinal needles used for the
some years ago by one of the authors
combined spinal-epidural technique.
(L.E.S.C.). The X-rays were performed
Anesthesia and Analgesia 1998; 86: 520±2. in an attempt to clarify why epidural
epidural needle through the dura. The 4 Fernando R, Collis R. Mobile epidural blocks had failed to maintain effective
spinal needle is advanced until a `dural'
click is felt which, with modem spinal
needles, is invariably followed by the
instantaneous appearance of CSF at the
techniques and new drugs in labour. In: pain relief throughout labour. In all
Reynolds F, ed. Regional Analgesia in
cases, an epidural catheter had been
Obstetrics ± a Millennium Update.
sited using a 16-g Tuohy needle with
London: Springer-Verlag, 2000: 81±109. the mother in the lateral position. A
hub. Although a dural click is usually 5 Parry M, Bawa GPS, Fernando R.
multihole catheter (side holes 0.5, 1 and
1.5 cm proximal to the catheter tip) had
been placed between 3 and 5 cm in the
epidural space and secured firmly to the
skin. Following delivery and informed
felt in over 90% of CSEs [6], if a click
does not occur during slow advance-
ment of the spinal needle, the presence
Clinical characteristics of commonly
used spinal needles. Anaesthesia 1995;
5
0: 1095±6.
of CSF within the hub at the point of 6 Stocks GM, Hallworth SH, Fernando
dural puncture indicates that further
advancement should cease. Since the
immediate appearance of CSF occurs on
dural puncture without the presence of
the stillette, the temptation to advance
the needle further than necessary, caus-
ing potential paraesthesia and nerve
damage, is avoided.
R. Evaluation of a spinal needle locking consent, a small volume of contrast
device for use with the combined spinal
epidural technique. Anaesthesia 2000;
55: 1185±8.
medium (Conray 280) was injected
through the epidural catheter and lateral
views of the lumbar spines taken.
In the first case (Fig. 8), part of the
catheter can be seen to have worked
its way out of the epidural space and
formed an almost semicircular loop
Fixation of epidural catheters
We should like to add to recent between skin and ligamentum flavum.
discussions on `migration' of epidural This epidural, although still function-
catheters and fixation devices. In their ing, was investigated for failing to
recent letter, Drs Tackaberry and Wads- provide adequate second-stage analge-
worth describe two cases in which sia. X-ray measurement of this catheter
working labour epidurals could not be revealed that at least half of the initial
extended for operative delivery (Tack- epidural portion was no longer in the
aberry & Wadsworth. Anaesthesia 1999; epidural space. Although all the injected
Second, during the intrathecal injec-
tion both the hub of the spinal needle
and the epidural needle should be
gripped firmly between the thumb and
the index finger of the anaesthetist's
hand while the back of the same hand
is simultaneously stabilised against the
patient's back.
5
4: 914). Interestingly, both catheters dye is shown in the epidural space, with
By adopting a slow advancement
technique and prior removal of the
spinal stillette combined with adequate
external stabilisation of both spinal and
epidural needles with the operator's
hand, our own spinal technical failure
rates have improved in association with
a paraesthesia incidence below 2%.
had not moved relative to the skin, a multihole catheter designed so that the
being fixed with the new Sims Portex most proximal hole was 1.5 cm from
Lockitw Epidural Catheter Clamp. The the tip, it is likely that further outward
authors postulated that catheters were movement would have resulted in some
pulled out of the epidural space by loss of injected solution into superficial
relative movement of tissues superficial tissues. Such is the case in Fig. 9. Again,
to the ligamentum flavum. Indeed, it the catheter can be seen to loop in the
has been demonstrated by Hamilton and superficial tissues where it has been
colleagues that there is significant move- pulled out of the epidural space. Dye
ment of catheters at the level of the skin can be seen in both the epidural space
as women change from the sitting flexed and the superficial tissues, indicating
to the lateral position [1]. Therefore, if that the likely cause of increased local
catheters are fixed firmly to the skin, the anaesthetic requirement was catheter
only movement of the catheter that can holes both inside and outside the
occur is outward through the ligamentum epidural space. In the third case, dye is
N. Levy
R. Fernando
Royal Free Hospital, London
References
Burnstein R, Buckland R, Pickett JA.
1
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Correspondence
Anaesthesia, 2000, 55, pages 1213±1235
.
...............................................................................................................................................................................................................................................
facilitated by the passage of many `mid- catheter design may be modified. The
line' catheters being inevitably through catheter described by Collier and Gatt
the edge of the paraspinous muscle, with three side holes all within 4 mm of
rather than being secured more firmly the tip was introduced to minimise the
in the narrow interspinous ligament (as risk of multicompartment injection [4].
demonstrated by the looping in Figs 9 This design may coincidentally reduce
and 10). Beillin and colleagues, using the risk of dislodgement as, compared
multihole catheters fixed firmly to the with standard wide spaced multihole
skin, found fewer problems when 5 cm catheters, a further 1 cm outward move-
was introduced into the epidural space ment is necessary before any side hole
when compared with 3 and 7 cm [2]. leaves the epidural space.
They suggested that failures occurred in
Although often overlooked, the
the 3-cm group because catheters had method by which epidural catheters
been dislodged, whereas the 7-cm group are secured, in addition to the length
had an increased risk of intravenous and of catheter insertion, is important in the
paravertebral placement. Using end-hole maintenance of adequate analgesia. It is
catheters, D'Angelo and colleagues not the purpose of this letter to
found that catheters inserted 2 cm into recommend lengths of catheter that
the epidural space were more likely to should be left in the epidural space,
become dislodged than those inserted 4, but we believe it confirms that if such
6
or 8 cm [3].
lengths are very short, the catheter is
In order to place sufficient catheter likely to move out of the epidural space
Figure 8 The epidural catheter has been
highlighted to demonstrate looping in the in the epidural space to avoid dislodge- no matter how effectively immobilised
superficial tissues although injection of dye ment without threading excessive length at skin level. Our X-ray studies suggest
produces a typical epidurogram. Arrows and thus increasing the risk of intra- that the ideal fixation device (as yet
mark the site where the catheter is fixed to venous and paravertebral placement, undevised) would secure the catheter at
the skin and where it exits the ligamentum
flavum.
or close to the skin puncture, but leave
2±3 cm between the fixation point and
seen only in superficial tissues as all
three catheter holes have been pulled
out of the epidural space (Fig. 10). In all
three cases the position of the catheter
had not moved relative to the skin.
Our cases provide further information
on the behaviour of epidural catheters
secured firmly to the skin. Securing
catheters in this way may not be the
most appropriate method of fixation as
only outward movement of the catheter
through the ligamentum flavum is possible,
with the potential for inadequate analgesia
as labour progresses. This possibility is
increased with shorter lengths of cathe-
ter inserted into the epidural space and
as some catheter movement is likely a
sufficient length should be inserted, the
length differing between single end-
hole and multihole catheters. Should
multihole catheters in which the proxi- Figure 9 The epidural catheter has been
mal end-hole is 1.5 cm from the tip highlighted and again loops in the super-
be placed less than 3 cm into the ficial tissues. Dye is seen both in the Figure 10 The epidural catheter has been
space, only 1.5 cm movement results epidural space and in the superficial highlighted and has pulled out of the
in this proximal hole pulling out of the tissues. Arrows mark the site where the epidural space with dye seen only in
epidural space. Such movement is not catheter is fixed to the skin and where it superficial tissues. An arrow marks the
uncommon [1]. This movement is exits the ligamentum flavum.
site where the catheter is fixed to the skin.
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Correspondence
.
...............................................................................................................................................................................................................................................
the skin puncture to allow for the migrate inward when the skin is
increased length of catheter required stretched, and back outward when the
for tissue movement between the skin skin is unstretched. In this situation, the
and ligamentum flavum. However, as catheter is usually anchored more to
some degree of outward movement is the ligamentum flavum than to the skin,
T. M. Duffy
Sir Charles Gardiner Hospital,
Perth, Western Australia
likely during the course of labour, therefore moving inward and outward A simple method for testing for
sufficient catheter length must be fed with less tendency to coil under the skin. the kinking epidural catheter
into the epidural space.
In the past, when we used a low-
quality `Curity' epidural catheter, we We would like to respond to the recent
occasionally had catheters kink under correspondence regarding `kinking'
the surface of the skin. However, we epidural catheters (Roddin & Dancey.
now use better quality `B. Braun' or Anaesthesia 2000; 55: 831) as our
`
Arrow' catheters, and have yet to see department has also experienced pro-
any sutured catheters kink under the blems with the SIMS Portex 16G clear
L. E. S. Carrie
R. Russell
John Radcliffe Hospital,
Oxford, UK
skin as a result of coiling.
Suturing the epidural catheter
epidural catheter with three lateral eyes.
Over a 4-day period, there were at
increases the epidural success rate and least six instances of epidural catheters
reduces the incidence of catheter dis- becoming blocked in our hospital. The
lodgement, one-sided anaesthesia and blockage could usually be relieved by
References
1
2
Hamilton CL, Riley ET, Cohen SE.
Changes in the position of epidural
catheters associated with patient
movement. Anesthesiology 1997; 86:
epidural vessel puncture [1].
altering the patients' position but often
recurred. In one labouring patient,
there were such frequent problems that
the Mefix tape that was securing the
epidural catheter to her back was
taken down to investigate the problem
further. On inspection, the catheter
was found to have become completely
kinked halfway down her back. When
the catheter was straightened the block-
age was relieved but the catheter appeared
to be damaged and would easily re-
occlude if the catheter was even slightly
7
78±84.
Beillin Y, Bernstein HH, Zucker-
S. Cohen
R. Morlend
UMDNJ ± Robert Wood Johnson
Medical School,
New Brunswick, NJ 08901, USA
Pinchoff B. The optimal distance that a
multiorifice epidural catheter should be
threaded into the epidural space.
Anesthesia and Analgesia 1995; 81: 301±4.
D'Angelo R, Berkebile BL, Gerancher
JC. Prospective examination of epidural
catheter nsertion. Anesthesiology 1996;
3
4
Reference
8
4: 88±93.
1 Cohen S, Lowenwirt I, Pantuck CB,
Pantuck EJ, Hronkova B, Buglisi J.
Suturing the epidural catheter reduces
Collier CB, Gaff SP. . A new epidural
catheter: Closer eyes for safety?
Anaesthesia 1993; 48: 803±6.
the incidence of failed epidural block in flexed again. In another patient, a similar
obstetric patients. Anesthsiology 1998;
8
kink occurred but the blockage was
permanent, as the catheter walls appeared
to have collapsed completely.
9: A1065.
Suturing epidural catheters
Figure 11 illustrates the problem
with the catheter kinking in this
defective supply batch. Figure 12 illus-
We read with interest the experiences Epidural tunnelling techniques
of Drs Scawn and Pennefather (Scawn
&
3
Pennefather. Anaesthesia 2000; 55: Another aid to epidural tunnelling trates a SIMS Portex catheter from a
04) in regard to fixing the epidural not mentioned in the recent editorial different batch, which demonstrates the
catheter too firmly at the level of the (Kumar & Chambers. Anaesthesia 2000; familiar resistance to kinking. Aware of
skin. In our own practice, we noticed 55: pp.625±6) is to leave the Tuohy this problem we have devised a simple
that when the epidural catheter is fixed needle in situ following passage of the test to check the catheters prior to use:
to the skin by a suture, it tends to be catheter until a subcutaneous tunnel has if the catheter is bent back on itself as
pulled away from the epidural space as been created with a 16G intravenous demonstrated in the photographs the
the skin stretches with each movement catheter passed from lateral to medial catheters prone to kinking are easily
of the patient. When the skin is exiting at the procedure site. Both identified.
unstretched, such as when a patient is needles can then be removed and the
Interestingly, the catheter in Fig. 12
upright, this excess epidural catheter catheter fed down the cannula, which is comes from an individually packed
coils under the skin. The excess coiled then removed. A small scalpel incision epidural catheter pack, which had a
catheter, warmed to body temperatures, may be necessary after the local anaes- bright green label on the front saying
is softened and thus may kink under the thetic prior to the initial passing of the `New Catheter material formulation'.
surface of the skin.
Tuohy to ease delivery of the tunnelling In contrast to what Roddin and Dancey
When the epidural catheter is not device but the chances of damage to described in their letter, we do not
sutured to the skin, but just secured with the epidural catheter or operator are appear to be have any problems with
a transparent sterile dressing, it tends to minimised.
this supply. The batch that was affected
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.
...............................................................................................................................................................................................................................................
similarities between ICU and A & E
practice. Indeed, I am certain that the
experience I gained in A & E managing
a huge variety of medical, surgical and
paediatric emergencies as well as fre-
quent resuscitation exposure is far more
useful to me than that gained in
medicine. Despite this, the Intercollegi-
ate Board for training in ICM has
stipulated that additional experience in
medicine alone is required for dual
CCST in anaesthesia and intensive
care. I fear that by reducing time in A
&
E to an `optional extra' the Board is
encouraging prospective intensivists to
miss critical care experience which A &
E is uniquely able to provide.
Figure 11
came from the custom-made epidural (A & E) and anaesthesia with particular
packs supplied to this hospital which reference to airway management in a
had no mention of the new material challenging patient population (Graham
P. Edgar
Queen Elizabeth Hospital,
Gateshead NE9 6SX, UK
formulation on them.
& Monro. Anaesthesia 2000; 55: 814). I
We too have reported this problem to would add acute pain control, conscious
SIMS Portex who are investigating it. sedation and perhaps even peripheral
The importance of this problem should nerve blockade to the list of areas where
not be underrated as at least six patients practice in our specialties is similar. In
received less than adequate pain relief and the same issue, Dr Rooney provides a
some were subjected to a second epidural succinct account of the reciprocal
From gasman to hospital
saviour: how far should we go?
Professor Websters' recent editorial adds
to the long-running correspondence on
the issue of peri-operative physicians in
this journal (Webster. Anaesthesia 2000;
insertion with all the inherent risks.
benefits of anaesthetic attachments to
other disciplines in terms of both
practical and theoretical teaching
J. Beamer
G. W. G. French
Northampton General Hospital,
Northampton NNI 5BD, UK
5
5: 839±40). I would like to add a few
(Rooney. Anaesthesia 2000; 55: 813).
comments to the debate. Firstly, I would
agree with Professor Websters' argu-
ment that adopting the title of peri-
operative physician is perhaps a step too
far at the moment. However, one aspect
of this ongoing debate is that there are
actually several related issues under
discussion; they overlap somewhat, but
also have some real differences worth
exploring.
Anaesthesia and A & E do indeed have
much in common, but what of intensive
care?
Before starting my anaesthetic career,
Value of attachments in A & E to I spent roughly equivalent time periods
intensive care training
working in both general medicine and
A & E. As I now progress through my
Graham and Munro remind us of the Specialist Registrar ICU attachments, I
overlap between accident and emergency am frequently struck by the obvious
Firstly, the expansion of our role to
participate in medical emergency teams
(MET), patient at risk teams (PART),
etc., and the development of `Intensive
Care without walls'.
Second, the expansion of our role
to that of peri-operative physicians with
responsibility for patient care from an
undetermined point pre-operatively to
another unidentified point postopera-
tively.
Third, the need to raise the status of
anaesthetists in the eyes of the general
public and other hospital staff.
Regarding the first issue, I fully
support the introduction of `Intensive
Figure 12
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.
...............................................................................................................................................................................................................................................
Care without walls'. The experiences of perspectives on management, and vice `For the times they are a-
McQuillan et al. [1] are undoubtedly versa. Ward rounds with visiting med- changing' ± or are they?
common in the UK and the results of ical specialists added much to our
introducing a MET speak for them- education and patient care. Becoming I read the recent editorial (Harmer.
selves. I feel that increasing the number a peri-operative physician runs the risk Anaesthesia 2000; 55: pp.735±6) and
of high-dependency units and improv- of depriving us of such opportunities for was particularly interested in the com-
ing identification of `sick' patients on ongoing learning.
the wards can only be of benefit to
ments concerning consultant office
On a practical (and lighter) note, to space. I work in a medium-size District
patient care. We as anaesthetists are the adopt the mantle of care for all patients General Hospital and as our consultant
logical choice to direct and lead such who have an anaesthetic from before numbers have increased we have
services.
admission until discharge from hospital squeezed more consultants into the
Regarding the expansion of our role is rather like volunteering to join the same space. The average office now
to become peri-operative physicians: Charge of the Light Brigade: noble, but has three desks and associated filing
many anaesthetists (perhaps the majority not especially good for one's health. If cabinets etc., leaving almost no floor
of those who entered the specialty in you imagine you will achieve undying area to move around.
the last few years) have acute medical gratitude for such nobility, read a little
experience. Dual qualifications (FRCA Kipling [3]. There is an acknowledged is a status symbol that goes with the
MRCP) are not uncommon. I would and large, unmet need for adequate consultant position and we cram in
Having an office with a personal desk
&
agree with Rooney [2] that all medical ward care [4], but few anaesthetic another desk with each new consultant
experience is beneficial (in fact, my departments would be capable of under- appointment. I carried out a casual
feeling is that it should be a prerequisite taking all of this extra work without a survey of the consultant usage of their
for entry to the specialty). However, great deal of additional resources. To offices and found that our consultants
knowledge does advance rapidly, and it attempt this without proper anticipation use their office less than 10% of the
is unlikely that many of us will retain of the work involved runs the risk of working week. For the great majority of
sufficient skill to provide a level of discharging both old and new roles the time the offices are empty as our
ongoing care equal to a specialist suboptimally, and of patients (as usual) consultants spend most of their time in
physician in all the specialties that we suffering the consequences. Addition- clinical areas.
anaesthetise for. It seems paradoxical to ally, doing two jobs badly will do little
aim for increased subspecialisation to enhance our status with anyone.
within anaesthesia (e.g. paediatric, car-
I suggest that the time has come to
change. I feel that we need to stop
thinking of an office and desk as status
symbols and think of them as functional
working areas. If we were to have one
desk per office and a personal filing
cabinet for each consultant using the
office then the office would be less
cluttered. One good-quality computer
could be shared between the occupants.
Office time could either be booked or
agreed at set times. As the offices are
used so little it is unlikely that there
would be a problem with congestion
and the consultant using the office
would have a better and more spacious
environment. Can we justify having so
much NHS real estate standing empty
for so much time to provide office space
to consultants that is so little used or
should the times be a-changing?
I. Nesbit
diothoracic, etc.) while advocating the
expansion of our role outside anaesthe-
sia. Perhaps rather than taking full
Freeman Hospital,
Newcastle upon Tyne, UK
responsibility for the minutiae of patient
care in such circumstances, we are
better placed to co-ordinate appropriate
References
1
2
McQuillan P, Pilkington S, Allan A et al.
Confidential inquiry into quality of care
before admission to intensive care.
British Medical Journal. 1998; 316:
care and referral when required. Dis-
cussion with parent medical and surgical
teams is more likely to improve overall
patient care than the unsolicited inter-
ference of someone armed with excess
confidence, outdated facts and poten-
tially rusty clinical skills. We should all
be aware of the limits of our abilities.
Some complex decisions are best dis-
1853±8.
Rooney KD. Six months acute
medicine makes a better doctor,
regardless of speciality! Anaesthesia.
2000; 55: 813.
cussed with the experts. As an aside, I 3 Kipling R. `The Last of the Light
recently spent a year working in a New
Zealand ICU: I was impressed at how
much interaction between specialties
Brigade'. In: The Works of Rudyard
Kipling. Ware: Wordsworth Editions,
1994: 200±2.
occurred. The surgical, medical and A 4 Ridley SA. Intermediate Care.
Possibilities, requirements and solutions.
Anaesthesia. 1998; 53: 654±64.
P. Royle
Hartlepool General Hospital,
Hartlepool TS24 9AH, UK
& E registrars on rotation to ICU taught
the anaesthetists useful skills and
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