Scholarly article on chloride hydrochloride 15364-23-5 from Journal fur praktische Chemie (Leipzig 1954) p. 240

Anaesthesia, 2003, 58, pages 597–616

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.

Correspondence

Herbal medicines in the

United Kingdom

4 Herbal products marketed as ginger are not commonly used as herbal

cosmetics. remedies in the UK. In 2002 the MCA,

Licensed products receive a Medi- on advice from the Committee on

I read with interest the review of peri- cines Control Agency (MCA) number. Safety of Medicines (CSM), revoked

operative implications of herbal medi- It is not possible to determine the top licences for preparations containing

cines (Hodges & Kam, Anaesthesia 2002: selling unlicensed products, since the kava because of the risk of liver toxicity

5

information pertinent to the UK.

7: 889–99) and wish to add some sector is largely unregulated. However, [6]. However, kava capsules (unlicen-

a survey has shown that the majority of sed) are readily available, including

The herbal medicines selected by British consumers buy the licensed on the Internet! Further regulation of

Hodges and Kam for detailed review products [4]. I have obtained lists of herbal medicine products (HMP) is

may be those most commonly used in the top selling licensed herbal medicines currently developing in Europe under

Australia, but are not the most popular in from the ﬁve most major U.K. manu- the auspices of the European Agency for

the UK. The popularity of herbal med- facturers (Potter’s, Chefaro, GR Lane’s, the Evaluation of Medicinal Products

icines will vary in different parts of the Herbal Concepts and Bioforce). Based (EMEA) – the aim is to establish a new,

world. Hence the authors of two other on this data the most commonly sold simpliﬁed system of licensing for tradi-

recent reviews selected somewhat differ- licensed herbs in the UK are:

ent lists of herbs for discussion [1, 2]. Also usually sole agents – echinacea, panax

in any area, the order of popularity can be ginseng, ginkgo, St John’s wort;

tional HMPs by 2005 [7].

Every herbal medicine is a complex

mixture of usually at least 50 chemical

expected to change with time.

There are four legal categories of herbs – valerian, garlic, passiﬂora, elder, mostlyunknown. It is consideredthatthe

herbal products in the UK [3]. white horehound, senna, uva-ursi. constituents may all contribute, perhaps

‘Medicinal products’ with a product

To the best of my knowledge, there synergistically, to the therapeutic action.

usually in combination with other constituents, the active principles being

1

licence under the Medicines Act 1968. have been no reported interactions In combination HMPs there are even

These may be prescription only, phar- between the last ﬁve herbs (not men- more chemical constituents for interac-

macy only or on the general sale list.

‘Medicinal products’ exempt from Kam) and anaesthetic drugs. However, Also, brands containing the same or

tioned in the review by Hodges and tion – additive, synergistic or negative?

2

licensing under section 12 of the Med- some are possible if these herbs are similar ingredients produced by different

icines Act 1968. Intended for herbalists, taken in excessive doses [5]. The fol- manufacturers can never be considered

initially these were only plants (dried, lowing herbs (used in combinations) are identical. There are concerns about use

comminuted or crushed), sold under also common in UK manufactured of the correct plant species, presence of

botanical name with no written instruc- products: aloes, buchu, cascara, clivers, contaminants such as insecticides, fung-

tions as to their use. However, this dandelion, elecampane, hops, kelp, icides or microorganisms, and deliberate

category came to include manufactured lobelia, saw palmetto, wild lettuce, adulteration [7]. This sort of information

products (under a specials manufactur- yarrow. For information on these I is beginning to be included in new

ing licence).

3

supplements.

commend the herbal medicines guide undergraduate medical curricula, but

Herbal products marketed as food commissioned by the Royal Pharma- most medical graduates know very little

ceutical Society [5]. Ephedra, kava and about HMPs.

All correspondence should be addressed to Professor M. Harmer, Editor of Anaesthesia, Department of Anaesthetics, University of

Wales College of Medicine, Heath Park, Cardiff CF14 4XN UK.

Letters (two copies) must be typewritten on one side of the paper only and double spaced with wide margins. In addition, please

include your letter as a Word for Windows or .rtf document on disk or alternatively submit as an e-mail attachment addressed to

anaesthesia@cf.ac.uk. Alternatively a response to a previously published article or letter can be submitted online at www.anaesthesia

correspondence.com. Copy should be prepared in the usual style and format of the Correspondence section. Authors must follow the

advice about references and other matters contained in the Notice to Contributors to Anaesthesia printed at the back of the January

and July issues. Author guidelines can also be found on www.blackwellpublishing.com/journals/ana/submiss.htm. The degree and

diploma of each author must be given in a covering letter personally signed by all the authors.

Correspondence presented in any other style or format may be the subject of considerable delay and may be returned to the author for

revision. If the letter comments on a published article in Anaesthesia, please send three copies; otherwise two copies of your letter will sufﬁce.

ꢀ

2003 Blackwell Publishing Ltd

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.

One wonders about the level of risk

References

that herbal medicines might add to 1 Sabar R, Kaye AD, Frost EAM.

measurement and a change in that

measurement over time, and for any

two quantities X and Y, X will be

correlated with X–Y; indeed, even if X

and Y are samples of random numbers

then one would expect the correlation

anaesthesia per se, and I suggest that this

is small. As of September 2002, the MCA

had not received any adverse drug reac-

tion reports involving interactions

Perioperative considerations for the

patient on herbal medicines. Middle

East Journal of Anesthesiology 2001;

16: 287–314.

between anaesthetic drugs and herbal 2 Cheng B, Hung CT, Chiu W. Herbal between X and X–Y to be 0.7 [1].

remedies (personal communication )

MCA ⁄ CSM). This does not of course

mean that nil adverse interactions have 3 http://www.mca.gov.uk/.

occurred, but it is perhaps not surprising 4 http://www.herbal-concepts.co.uk.

as skilled anaesthetists titrate anaesthetic 5 Newall CA, Anderson LA, Phillipson

medicine and anaesthesia. Hong Kong

Medical Journal 2002; 8: 123–9.

The same problem appears to occur

when measuring the agreement between

two methods of clinical measurement:

Ratnasabapathy et al. cite a reference

by Bland and Altman which reports a

drugs and adjuncts according to patient

response. Of course, I support the elicit-

ing of herbal medicine usage by anaes-

thetists at pre-operative visits. However, 6 Editorial. News Feature. Pharmaceutical

this information may be more relevant to

Journal 2002; 269: 128.

surgeons and physicians with regard 7 Anonymous. Meetings and Confer-

JD. Herbal Medicines. A Guide for Health statistical method for assessing agree-

Care Professionals. London: The Phar-

ment between two methods of clinical

measurement [2]. Bland and Altman

point out that it is a mistake to plot the

difference between two variables against

either value separately because the dif-

ference will be directly related to each;

this statistical artefact is further illustrated

maceutical Press. 1996; 280–2.

to the longer term well-being of the

patient.

ences. The Pharmaceutical Journal 2002;

269: 403–5.

The example of the patient in whom 8 Karliova M, Treichel U, Malago M et al. in an earlier article by Gill et al. [3]. The

rejection of a liver transplant was caused

by the ingestion of St John’s wort as an

antidepressant after discharge from hos-

pital, comes to mind [8].

Interaction of Hypericum perforatum

(St. John’s wort) with cyclosporin A

metabolism in a patient after liver

transplantation. Journal of Hepatology

2000; 33: 853–5.

correct method, as indicated above, is to

plot the difference between two vari-

ables against the arithmetic mean of the

two variables. Figure 3, from the article

by Ratnasabapathy et al. appears to use

the correct method in illustrating the

relationship between ﬁxed and portable

Discontinuing herbal medication for

2

weeks prior to surgery may be sen- 9 Garges HP, Varia I, Doraiswamy PM.

sible advice in most cases, but this

remains debatable for some herbal med-

icines. For example, abruptly stopping

valerian may precipitate symptoms

mimicking an acute benzodiazepine

withdrawal syndrome [9]. The editorial

on herbal medicines (Sehgal & Hall.

Anaesthesia 2002; 57: 947–8) mentioned

valerian and alluded to alternative

therapy. Substituting a benzodiazepine

is an option, but I suggest that in many

cases it would be perfectly reasonable to

simply continue the valerian in the

peri-operative period. Furthermore,

in emergency cases, 2 weeks dis-

continuation is impossible, and the

anaesthetist must proceed with due

attention.

Cardiac complications and delirium

associated with valerian root with-

drawal. Journal of the American Medical

Association 1998; 280: 1566–7.

0

F CO2. The general effect of using the

E

incorrect method appears to be to increase

the value of the correlation coefﬁcient

[3].

I would be pleased to hear if Ratna-

sabapathy et al. agree with my inter-

pretation of the above methods. I

cannot comment upon the effect of

any new analysis of the data by Ratna-

sabapathy et al.

Evaluation of an expired

fraction carbon dioxide

monitor – incorrect statistical

analysis?

I read with interest the recent article

concerning the evaluation of an expired

fraction carbon dioxide monitor (Rat-

nasabapathy et al. Anaesthesia 2002; 57:

I. H. Lewis

Southampton General Hospital,

Southampton, SO16 6YD, UK

E-mail: ihlewis01@aol.com

9

the difference between two variables

00–4). Figures 5 and 6 both illustrate

0

(

^a^r^t^e^rⁱ^a^l^P^C^O2 – portable F CO2)

a

E

References

plotted against the one of the same

variables (arterial P CO ). If the arterial

1

2

Altman DG. Practical Statistics for Medical

Research, 1st edn. London: Chapman &

Hall, 1991: 284–5.

The UK herbal medicine industry is

currently booming. Anaesthetists can be

sure of encountering many patients

taking herbal remedies and some know-

ledge of the subject is clearly required.

A survey of current anaesthetic practice

is called for.

a

2

0

P CO and portable F CO2are consid-

a

2

E

ered to be two different methods of

estimating a single clinical measurement

legitimised by plotting the difference

between these two variables on the

y-axis of Figs 5 and 6) then the correct

method would be to plot the arithmetic

Bland JM, Altman DG. Statistical

methods for assessing agreement

between two methods of clinical

measurement. Lancet 1986; 1:

(

3

07–10.

A.G. McKenzie

3

Gill JS, Beevers DG, Zezulka AV et al.

Relation between initial blood pressure

and its fall with treatment. Lancet 1985;

i: 567–9.

Royal Inﬁrmary,

mean of the arterial P CO and portable

a 2

0

Edinburgh EH16 4SA, UK

E-mail: mckenzie_alistair@

hotmail.com

F CO2 on the x-axis. This error may

E

arise with the use of correlation to study

the relationship between an initial

5

98

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Anaesthesia, 2003, 58, pages 597–616

Correspondence

....................................................................................................................................................................................................................

.

Method Comparison plot - Group B

lines ) we should have refrained from

including these in the graphs.

2

1

0

.5

2

While Dr Lewis is entirely correct to

say that the correlation between the

measurements is more accurately related

to the average of the measurements, the

charting methodology does not change

the difference between the two meas-

urement techniques, which we believe

to be signiﬁcant.

.5

1

We also believe the reader needs to

appreciate the difference over the clin-

ical range of pCO , so that they may

2

R

= 0.5818

.5

0

2

then relate that to the clinical changes

that appear with increasing pCO₂.

An average of the test and standard

3.6

3.8

4

4.2

4.4

4.6

4.8

5

Average (arterial pCO2 +portable FÉCO2) [kPa]

do not tell the reader that at a pCO of

2

5

.6 kPa, the portable capnometer

under-read by 1.5 kPa. The ﬁgure of

.6 has more immediate clinical

Figure 1

5

relevance, in terms of cerebral blood

ﬂow and intracranial pressure, than the

average of 4.85. This is perhaps an

argument between the practically useful

graphical depiction of data and the

accurate statistical interpretation of

graphed data.

Method Comparison plot - Group C

1.6

1.4

1.2

1

Our essential point remains, how-

ever, that this type of monitor needs to

be tested against the clinically relevant

0.8

0.6

0.4

0.2

0

2

R

= 0.1568

variable, i.e. pCO , and in a variety of

2

circumstances, so as to gain insight into

its performance in the various environ-

ments it may be used.

4

.4

4.6

4.8

5

5.2

5.4

5.6

5.8

–0.2

M. J. Souter

Harborview Medical Center,

Seattle WA 98104–2499, USA

E-mail: msouter@u.washington.edu

–0.4

Average (arterial pCO2 +portable FÉCO2) [kPa]

Figure 2

change in the slope of correlation in Nasotracheal intubation

Fig. 2, whilst Fig. 1 is largely unchanged.

A reply

We are grateful ﬁrstly to Dr Lewis for his There remains, however, a measurement In their excellent article on nasotracheal

interest in our paper, and for cogently difference of 0.4 kPa at an average of intubation for head and neck surgery,

illustrating the statistical argument, and 5 kPa pCO in Fig. 6.

secondly for the opportunity to reply to

his points. He is absolutely correct in any researcher in depicting this type of of intubation under direct vision and

the authors (Hall & Shutt. Anaesthesia,

Herein lies part of the problem facing 2003, 58: 249) discuss the techniques

2

terms of statistical accuracy ) there are data. What does charting the average of blindly. However, they do not mention

errors inherent in charting the difference pCO and F

CO tell the clinical user? the highly successful technique which is

between a standard and test measurement We would argue that this was a study of a combination of these two [1]. Here,

against only the standard, in terms of clinical accuracy, and the graph was the laryngoscope is used merely to place

E 2

´

2

the correlation produced.

structured to depict the deviation the tip of the tube optimally (i.e. in the

For interest’s sake, we include the between what we accept as our clinic- midline and posterior to the epiglottis)

revised graphs of our data using the ally important variable (i.e. pCO ) and under direct vision, a limited procedure

2

‘

(

statistically

correct’

Figs 1 and 2). They indeed show a here lay in including the correlation formal laryngoscopy. The upward lift of

methodology the tested variable (F_E

´

CO ). Our error producing far less stimulation than

2

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.

the laryngoscope is then relaxed, allow- point we decided to administer an like percutaneous tracheostomies, cen-

ing the soft tissues to fall back into their ‘interscalene’ brachial plexus block, to tral venous line insertion, cervical spinal

normal anatomical positions before the achieve better intra-operative and nerve blocks (stellate ganglion blocks,

tube is advanced blindly into the larynx. postoperative analgesia. A 24 gauge cervical plexus blocks, etc.), endoscop-

Even in inexperienced hands this tech- (1-inch-long) intradermal needle was ies and surgery on and around the neck

nique is almost always successful, and it taken and the landmarks for the block [3–5]. Most of these procedures involve

deserves to be more widely known. It is identiﬁed according to the standard the use of needles or sharp instruments,

suitable for routine use and is often the interscalene technique as described by which, if not used carefully, especially

quickest and easiest solution to the Winnie [2]. On introducing the needle, in patients not having well deﬁned

more difﬁcult case.

a ‘give way’ was felt and it was assumed anatomical landmarks, may endanger

to be the prevertebral fascia covering our anaesthetic equipment and, more

the scalene muscles forming the ‘inter- importantly, our patients. A high degree

scalene’ space. After negative aspiration, of caution and vigil is recommended

15 ml of 0.375% bupivacaine was injec- during procedures being performed

ted. No resistance to injection was around the trachea with an airway

J. Powell

Bristol BS32 4HD, UK

E-mail: johnpowell@uk2.net

Reference

experienced. As the surgeons prepared device in situ.

and draped the operative site, gurgling

N. Saxena

1

Powell J. Gasman – A Personal History of

Anaesthesisa. Chap. 9: 1978. http://

www.johnpowell.net: Powell 1999

Direct link: http://www.johnpowell.

net/gasman/9oxy.htm#9780.

sounds with each breath were heard.

S. Ahuja

Another 4 ml of air was injected into

University College of Medical Sciences

the cuff. Over the next minute, the

and Guru Teg Bahadur Hospital,

gurgling sounds reappeared. In an

Delhi-110095, India

attempt to inﬂate the cuff correctly with

E-mail: neesax2003@yahoo.co.in

the prescribed volume, we decided to

Laryngeal mask cuff damage

during interscalene block

deﬂate the cuff and re-inﬂate it. On

aspirating, clear, transparent ﬂuid (ca.

References

1

Hayakawa M, Morimoto Y, Kemmotsu

O. Tracheal tube damage by Harmonic

Scalpel during tonsillectomy. Masui

Inadvertent iatrogenic injury to airway 5 ml in volume) appeared. Attempts at

management aids resulting in a loss of re-inﬂating the cuff failed and it was

airway security is a possibility of which decided to intubate the trachea. The

every anaesthetist should be aware. laryngeal mask was removed, thorough

Damage to a tracheal tube during an oropharyngeal suctioning was done,

operative procedure in and around the vecuronium bromide 3 mg iv given

neck is a possibility and has been and the trachea intubated with an

reported [1]. We would like to report appropriate sized cuffed tracheal tube.

a recent case of accidental puncture of a Tracheal suctioning was done and no

laryngeal mask airway cuff while per- signiﬁcant aspirate was found. The rest

forming an ‘interscalene’ brachial plexus of the procedure was uneventful and the

2

000; 49: 1261–2.

2

3

Winnie AP. Interscalene brachial plexus

block. Anesthesia and Analgesia 1970;

4

9: 455–66.

Dexter TJ. The Laryngeal mask airway;

a method to improve visualization of

the trachea and larynx during fibreoptic

assisted percutaneous tracheostomy.

Anaesthesia and Intensive Care 1994; 22:

block.

A 10-year-old boy (25 kg) had pre-

patient’s recovery was adequate.

On careful examination of the laryn-

3

5–9.

4

5

Heath MZ. The reinforced laryngeal

mask airway for adenotonsillectomy.

British Journal of Anaesthesia 1994;

sented to the orthopaedic surgeons geal mask, we found ﬂuid in the

following a fall from height. A diagnosis inﬂating lumen and a small puncture

of a supracondylar fracture of the left on the left dorso-lateral aspect of the

humerus was reached and closed reduc- cuff. Our needle had accidentally

tion was planned. After performing the entered the cuff of the laryngeal mask

routine pre-anaesthetic check-up and and its silicone material had given a false

conﬁrming the fasting status, a general positive ‘loss of resistance’ feel. As the

anaesthetic technique was planned. drug had been injected into the cuff,

7

2: 728–9.

Alexander CA. A modified Intavent

laryngeal mask for ENT and dental

anaesthesia. Anaesthesia 1990; 45: 892–3.

Fentanyl 40 lg iv was given and anaes- some of it leaked into the oropharynx Hard to swallow

thesia was induced with propofol 60 mg from the puncture site while some was

iv. A size 2.5 laryngeal mask airway was aspirated from the cuff inﬂation port.

inserted and the cuff ﬁlled with about This report highlights the risk that haematoma complicating apparently

2 ml of air. Anaesthesia was main- vital anaesthetic equipment is exposed straightforward tracheal intubation.

tained with O , N O and halothane to when interventions are done around An 83-year-old 67-kg man, ASA

1%). Closed reduction was attempted them. The laryngeal mask airway has class II and Malampati I, was scheduled

under ﬂuoroscopic guidance but stabil- revolutionised anaesthesia because of for laparoscopic cholecystectomy

We wish to report a retrothyroid

1

2

(

a

ity could not be achieved. The opera- the ease, simplicity and safety it offers under general anaesthesia. Pre-operative

tive plan was changed to open over the conventional tracheal tube. It anaesthetic assessment identiﬁed chin

reduction and internal ﬁxation. At this has gained widespread use in procedures recession and a slightly decreased range

6

00

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Correspondence

....................................................................................................................................................................................................................

.

of neck movement secondary to osteo-

arthritis. There was no history of neck

trauma, thyroid pathology, dysphagia,

cerebrovascular disease or bleeding dis-

orders. Laryngoscopy (grade 2) was

performed with Macintosh size 4 blade,

and an 8.0-mm cuffed tracheal tube

inserted easily by an experienced con-

sultant anaesthetist. An 18F nasogastric

tube was passed, and neck veins were

not cannulated. Surgery was straight-

forward and extubation uncomplicated.

On the ﬁrst postoperative day, the

patient complained of being unable to

swallow and neck pain, without respir-

atory difﬁculty. Examination elicited

tenderness around the left thyroid lobe

but was otherwise unremarkable; there

was no neurological deﬁcit. A speech

and language therapy assessment repor-

ted dysphagia and aspiration, but ﬂex-

ible nasolaryngoscopy was normal.

A barium swallow (Fig. 3) showed

minor deviation of the cervical oeso-

phagus to the right, with aspiration of

a small amount of contrast. Ultra-

sound (Fig. 4) and computed tomogra-

phy scans (Fig. 5) of the neck showed

an eccentric 4 · 2.2 · 1.7 cm ﬂuid

collection, displacing the left thyroid

lobe and isthmus, consistent with a

retrothyroid haematoma.

The patient reported a progressive

decrease in discomfort over a fortnight.

However, persistent dysphagia necessi-

tated placement of a ﬁne bore feeding

nasogastric tube, later replaced by a

percutaneous endoscopic gastrostomy

tube for nutrition. Complete resolution

of symptoms took 8 months.

A sore throat often follows tracheal

intubation, is generally short-lived, and

is reportedly reduced by light wand

intubation [1], preferential use of the

laryngeal mask [2], and spontaneous as

omy. Similar symptoms to those des-

cribed by this patient are commonly

reported following tracheal intubation,

and their implications, were he in the

community, may have been underesti-

mated. Prior to embarking upon day

surgery, it is crucial that robust systems

are in place in the community to

provide a safety net for similar poten-

tially serious if isolated cases.

M. D. Horwitz

M. Jonas-Obichere

T. C. Holme

Lister Hospital,

Stevenage SG1 4AB, UK

E-mail: maxim.horwitz@

btopenworld.com

References

Friedman PG, Rosenberg MK,

1

2

Lebenbom-Mansoum M. A compar-

ison of light wand and suspension lar-

yngoscopic intubation techniques in

outpatients. Anesthesia and Analgesia

Figure 4

1

997; 85: 578–82.

Saeki H, Morimoto Y, Yamashita A

et al. Postoperative sore throat and

intracuff pressure: comparison among

endotracheal intubation, larnygeal mask

and cuffed oropharyngeal airway.

Japanese Journal of Anesthesiology 1999;

4

8: 1328–31.

3

Figuerdo E, Viver-Diego M,

Manuz-Blanco F. Laryngo-pharyngeal

complaints after use of the laryngeal

mask airway. Canadian Journal of

Anaesthesia 1999; 46: 220–5.

Figure 5

opposed to intermittent partial pressure

ventilation [3]. In this case, symptoms

were due to a retrothyroid haematoma, An unusual case of

probably caused by bleeding from small postextubation stridor

neck veins. Despite an apparently

straightforward anaesthetic, thyroid A 63-year-old lady presented to the day

movement with the trachea during surgery unit for nasal polypectomy. Her

intubation or coughing on extubation past medical history included allergic

may have initiated bleeding. Similarly, rhinitis, nasal polyps and mild asthma.

nasogastric intubation may have caused Her current medications were salbuta-

unsuspected trauma.

mol and becotide inhalers. She smoked

This case presents an unpredictable, 15 cigarettes per day and had recently

serious and potentially life-threatening ﬁnished a course of antibiotics for a

complication of tracheal intubation. chest infection. Apart from her normal

The retrothyroid haematoma displaced smoker’s cough, she denied any symp-

the oesophagus causing dysphagia; for- toms of cardiorespiratory compromise.

tunately, airway compression and res- Previous anaesthetic history was unre-

piratory compromise did not occur. markable having had an uneventful

However, this raises particular concern abdominal hysterectomy 20 years pre-

for day case laparoscopic cholecystect- viously. Examination revealed a highly

Figure 3

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)1

anxious patient with normal cardiovas- oedematous polyp on the left vocal cord, 0.25 mg.kg has previously been used

cular and respiratory systems. Her which moved to partially occlude the to control post extubation and func-

weight was 59 kg and her calculated laryngeal glottis with jetting of the tional laryngospasm [3, 4]. Studies have

)

2

BMI was 29 kg.m .

Anaesthesia was induced with mida- occlusion did not appear signiﬁcant atory events including laryngospasm are

Sanders injector. Although the partial demonstrated that peri-operative respir-

zolam 1 mg, fentanyl 100 lg, propofol enough to account for the patient’s more common in smokers [5, 6]. The

1

20 mg and vecuronium 4 mg. Lary- respiratory compromise, the decision ENT surgeon who performed the nasal

ngoscopy revealed a grade II view and was made to excise the polyp. The rest polypectomy felt that the procedure

the patient’s trachea was intubated with of the laryngeal structures appeared might need to be repeated in the future.

a 7.0-mm cuffed RAE tube. A throat normal. Following neuromuscular Our plan would be to anaesthetise the

pack was inserted and anaesthesia main- reversal and demonstration of the return patient using a laryngeal mask airway

tained with a mixture of oxygen, air and of airway reﬂexes, the patient was extu- and propofol TCI.

isoﬂurane. At the end of the procedure, bated. As before, the patient initially

4

S. Lewis

0 min later, the throat pack was appeared ﬁne, but then became dis-

A. Jardine

removed and the patient’s postnasal tressed with concomitant inspiratory

space, pharynx and larynx suctioned stridor and hypoxia. The hypoxia

under direct vision. The patient was responded to high ﬂow oxygen; how-

reversed with neostigmine 2.5 mg and ever, the stridor and agitation remained.

glycopyrronium 500 lg and placed in a The possibility of a vocal cord palsy was

left lateral position. Following the raised and it was decided to perform

demonstration of adequate tidal volumes nasendoscopy. The patient was sedated

Royal United Hospital,

Bath BA1 3NG, UK

References

1

2

Gallivan GJ, Hoffman L, Gallivan KH.

Episodic paroxysmal laryngospasm:

voice and pulmonary function assess-

ment and management. Journal of Voice

and a good cough reﬂex, the patient’s with

a

propofol infusion (TCI

)1

trachea was extubated. Immediately fol- 1.5 lg.ml ) and the nasal mucosa

lowing extubation the patient demanded anaesthetised with lidocaine 1%. As the

to sit up. Over the ensuing couple of propofol sedation approached the target

1

996; 10: 93–105.

Schmidt M, Brugger E, Richter W.

Stress-inducible functional laryngo-

spasm: differential diagnostic consider-

ations for bronchial asthma. Laryngology

Rhinolology and Otology 1985; 64: 461–5.

Nawfal M, Baraka A. Propofol for the

relief of extubation laryngospasm.

Anaesthesia 2002; 57: 1036.

)

1

minutes the patient became increasingly level of 1.5 lg.ml , it was noted that

distressed and complained of difﬁculty the patient’s stridor had resolved and she

breathing. At the same time, it appeared was able to cough effectively and pho-

that she had an inadequate cough and nate normally. Nasendoscopy was per-

that secretions were accumulating in her formed and demonstrated normal

upper and lower airways. She demon- symmetrical movement of the vocal

strated good muscle strength and a train- cords. With constant reassurance to the

of-four stimulation showed no fade. patient, the propofol sedation was

Over the next 5 min, she developed weaned over the next 20 min with no

increasing inspiratory stridor, respiratory further problems. Once fully recovered,

distress and her oxygen saturations fell to discussion with both family and patient

3

4

5

Langrish CJ, McCrirrick A. Another

case of disappearing wheeze. Anaesthesia

1

999; 54: 499.

Schwilk B, Bothner U, Schraag S,

Georgieff M. Perioperative respiratory

events in smokers and nonsmokers

undergoing anaesthesia. Acta Anaesthes-

iologica Scandinavica 1997; 41: 348–55.

Myles PS, Iacono GA, Hunt JO et al.

Risk of respiratory complications and

wound infection in patients undergoing

ambulatory surgery: smokers versus non

smokers. Anesthesiology 2002; 97: 842–7.

8

5% despite high-ﬂow oxygen and revealed that the patient was prone to

manual CPAP by facemask. Following panic attacks. During two of these

propofol 80 mg and succinylcholine attacks, it had been noted by family

7

5 mg, she was re-oxygenated and members that the patient’s breathing had

6

direct laryngoscopy surprisingly revealed become ‘noisy’ and had necessitated

no blood or secretions in the larynx. The review by the emergency on-call doctor.

patient’s trachea was intubated with a

Although our patient had a polyp on

size 7.0 mm cuffed tracheal tube. Fibre- her vocal cord, we do not feel that this

optic bronchoscopy demonstrated no was the primary cause of her postextu-

blood or secretions in the lower airways bation laryngospasm. The most likely

but blood could be visualised tracking cause was an acute panic attack preci-

down the outside of the tracheal tube. pitated by the stress of extubation and

An ENT surgeon was summoned, as initial post anaesthetic disorientation. Training method of applying

laryngeal trauma could not be excluded. The evidence to support this comes pressure on the neck for

The tracheal tube was removed and from the patient’s previous history and laryngoscopy: use of a

direct laryngoscopy performed with the fact that it settled spontaneously videolaryngoscope

ventilation of the lungs via a Sanders with conscious propofol sedation.

injector. Anaesthesia was maintained Functional paroxysmal laryngospasm Application of pressure on the neck, such

using a target-controlled infusion (TCI) (laryngeal dyskinesia) can be associated as cricoid pressure [1] or backward,

)

1

of propofol (range 4–6 lg.ml ). Direct with psychological disorders including upward and rightward pressure (BURP)

laryngoscopy revealed the presence of an panic attacks [1, 2]. Propofol at a dose of on the thyroid cartilage [2], may improve

6

02

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Correspondence

....................................................................................................................................................................................................................

.

the view of the glottis at laryngoscopy.

However, inappropriately applied pres-

sure may worsen the view [1]. Therefore,

training of the correct application of

pressure is mandatory. One major difﬁ-

culty in teaching is that it is difﬁcult to

show trainees or assistants the change in

the view of the glottis by pressure on the

neck. We suggest that the use of a device

that enables the view of the glottis to be

displayed on a video screen is useful for

teaching purposes.

One simple method is to place a small

camera or tip of a ﬁbrescope (with a

video screen) near the mouth during

laryngoscopy to show the image, but

three people may be required to insert a

laryngoscope, to hold a camera system,

and to apply pressure on the neck. A

better way is to attach a ﬁbrescope to a

laryngoscope. Henthorn and colleagues

were the ﬁrst to report a system of

attaching a ﬁbrescope to a Miller lar-

yngoscope [3]. Several Macintosh blades

that incorporate ﬁbreoptic systems are

now commercially available, and we

have been using such a device (X-lite

blade aids teaching direct laryngoscopy. postoperative haematocrit or red cell,

Anesthesia and Analgesia 1995; 80: 433.

fresh frozen plasma or cryoprecipitate

use between groups. However, signiﬁ-

cantly more platelets were administered

to patients in the clopidogrel (mean ¼

6 units) and aspirin + clopidogrel (mean

3.4 units) groups compared to the

no antiplatelet therapy group (mean

3.3 units) (p ¼ 0.005). Patients in the

aspirin only group were minimally

exposed (mean 1.4 units, p > 0.2).

Clopidogrel and platelet

transfusion in patients

undergoing coronary artery

bypass graft surgery*

We read with interest the timely review

of clopidogrel (Kam & Nethery. Anaes-

thesia 2003; 58: 28–35). Current recom-

mendations for withholding clopidogrel

for 6–7 days before elective cardiac

artery bypass graft (CABG) surgery has

recently been echoed in the American

College of Cardiology ⁄ American Heart

Association practice guidelines for man-

agement of patients with unstable angina

We believe that this data showing a

2–5 donor exposure increase in CABG

patients receiving clopidogrel alone or

with aspirin is signiﬁcant for anaesthet-

ists. Because of the retrospective inves-

tigation, patient group sizes were

unequal and there was no prospectively

deﬁned transfusion algorithm. How-

ever, there was a stable cohort of cardiac

anaesthetists and surgeons over this

period, and blood product transfusion

was guided, in part, by the Thrombelas-

[

1]. Nonetheless, there has been a relative

absence of data examining risks of bleed-

ing and blood product transfusion in

CABG patients receiving pre-operative

clopidogrel. We wish to share our data

after evaluation was prompted by a

perceived increase in bleeding and blood

product use in such patients.

Ò

tograph . Similar rates of other trans-

fused blood products and postoperative

haematocrits between groups suggest

that platelet transfusions were a timely

intervention to correct the defect in the

clopidogrel groups without signiﬁcant

observer bias. These data were presented

to our cardiology colleagues, who will

be the most likely physicians able to

identify appropriate patients for clopi-

dogrel withdrawal, before anaesthetic or

surgical evaluation, which is often with-

in the 7-day window.

Until publication of further prospect-

ive data of the peri-operative implica-

tions of clopidogrel, we agree with Kam

and others [2] that clopidogrel be

withheld for 5–7 days before elective

CABG surgery.

After institutional approval,

a

Video

Laryngoscope,

R u¨ sch,

retrospective study was conducted of all

ﬁrst-time CABG surgeries at a univer-

sity-based teaching hospital for the ﬁrst

Germany). We have found that an

anaesthetist inserting the laryngoscope

can show an effective way of applying

pressure on the neck because both the

anaesthetist and the assistant applying

pressure on the neck can see the glottic

area on a video screen and see the effect

of the applied pressure on the view of

the glottis. We believe that, although

9

months of 1999. Patients with abnor-

mal baseline coagulation parameters,

undergoing combined procedures or

with an intra-aortic balloon pump were

excluded. Intra- and postoperative blood

loss and BP administration were recor-

ded for four groups: patients receiving

aspirin (A) alone (n ¼ 80), clopidogrel

availability of

a

video-monitored

laryngoscope is currently limited, this

should become more widely available.

(

C) alone (n ¼ 16), A + C (n ¼ 47) or

no antiplatelet therapy (n ¼ 41). Trans-

fusion data were not normally distributed

and analysed with Kruskal–Wallis tests:

signiﬁcant differences were evaluated by

Wilcoxon rank-sum tests between

groups with Bonferroni correction.

T. Asai

K. Murao

K. Shingu

E. G. Pivalizza

Kansai Medical University,

Moriguchi, Osaka, 570–8507,

Japan.

R. D. Warters

L. I. Gottschalk

There were no differences in patient

demographics, baseline coagulation

parameters, duration of cardiopulmon-

ary bypass (CPB), lowest temperature

on CPB, estimated blood loss,

S. L. Luehr

E-mail: asait@takii.kmu.ac.jp

E. A. Hartwell

University of Texas Health Science

Center-Houston, Houston,

Texas 77030, USA

References

1

2

Vanner RG, Asai T. Safe use of cricoid

pressure. Anaesthesia 1999; 54: 1–3.

Knill RL. Difficult larygnoscopy made

E-mail: Evan.G.Pivalizza@uth.tmc.edu

*Preliminary data presented in abstract

easy with a ‘BURP’. Canadian Journal of form at the Society of Cardiovascular References

Anaesthesia 1993; 40: 279–82. Anaesthesiologists Annual Meeting, Orla- 1 Braunwald E, Antman EM, Beasley JW

3

Henthorn RW, Reed J, Szafransk JS,

Ganta R. Combining the fiberoptic

bronchoscope with a laryngoscope

ndo, FL, 2000 and published as a meeting

abstract in a supplement in Anesthesia and

Analgesia 2000; 90: SCA 14.

et al. ACC ⁄ AHA 2002 guideline

update for the management of patients

with unstable angina and non-ST

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2003 Blackwell Publishing Ltd

603

Correspondence

Anaesthesia, 2003, 58, pages 597–616

....................................................................................................................................................................................................................

.

segment elevation myocardial infarc-

tion. Circulation 2002; 106: 1893–900.

Kovesi T, Royston D. Is there a problem

with platelet active drugs? British Journal

of Anaesthesia 2002; 29: 159–63.

2 Homoncik M, Jilma B, Hergovich N ﬁrst performed to exclude distal disease.

et al. Monitoring of aspirin (ASA)

pharmacodynamics with the Platelet

Function Analyzer PFA-100Ò.

A right carotid endarterectomy was

performed and heparin given prior to

insertion of a Javid shunt. Heparin was

2

Thrombosis and Haemostasis 2000; 83: reversed with protamine sulphate upon

3

16–21.

completion of the endarterectomy. The

tracheal tube was changed to a left

double lumen tube and right subclavian

vein cannulation was performed. An

Ivor Lewis oesophagectomy was per-

formed which involved a laparotomy

3

Von Pape K, Aland E, Bohner J.

Platelet Function Analysis with

PFA-100Ò in patients medicated

with acetylsalicylic acid strongly

depends on concentration of sodium

Monitoring of platelet function

We read with interest the recent review

about thienopyridine antiplatelet drugs

(

2

Kam & Nethery. Anaesthesia 2003; 58:

8–35). A major problem faced by

citrate used for anticoagulation of blood to mobilise the stomach and form a

sample. Thrombosis Research 2000; 98:

95–9.

gastric tube, mobilisation of the oeso-

phagus through a right thoracotomy

and an end-to-end anastomosis.

Abdominal and chest drains were

inserted. The double lumen tube was

exchanged for a cuffed tracheal tube

and the patient transferred to the

intensive care unit. He was extubated

after 4 h, moved all limbs and answered

questions appropriately. Recovery was

uneventful.

anaesthetists is the monitoring of the

effects of antiplatelet medication.

Although the platelet function analyser

2

4

Mallett SV, Platt M. Role of thromb-

elastography in bleeding diatheses and

regional anaesthesia. Lancet 1991; 338:

(

PFA-100, Dade Behring, Dearﬁeld, IL)

appears to be the answer to this problem,

it is a global test of primary haemostasis

and is not speciﬁc for antiplatelet drugs

7

65–6.

[

1]. The PFA-100 has been used to

monitor the antiplatelet effect of aspirin

2]; however, the results may be affected

Combined carotid

endarterectomy and

oesophagectomy

[

by the citrate concentration in the

sampling tube [3]. There is less experi-

ence in use of the PFA-100 to assess the

effect of clopidogrel, and it is uncertain

whether the citrate concentration is also

important in this situation. Results from

the PFA-100 may also be affected by

smoking, haematocrit and gender [1].

The ThrombelastographÒ (TEGÒ)

Haemostasis Analyser (Haemoscope

Corp., Niles, IL, USA) is a near-patient

method of monitoring whole blood

coagulation. Standard use of the TEGÒ

system cannot detect the effect of

aspirin [4]. However, a new TEGÒ

assay has been developed speciﬁcally for

this purpose (Personal communication:

Haemoscope Corp., Niles, IL, USA).

The use of antiplatelet medication has

implications for the safety of regional

anaesthesia and propensity to bleed

during surgery. Further studies are nee-

ded to provide a sufﬁciently robust

method of platelet function assessment

to guide anaesthetic management.

Carotid surgery reduces the late

The beneﬁts of combined operations incidence of stroke when compared to

of carotid surgery and coronary artery medical treatment and overall mortality

bypass graft (CABG) are well recog- ranges between 1 and 2% [2, 3]. Oeso-

nised in decreasing the incidence of phageal resection represents a major

stroke [1]; however, combined carotid surgical and physiological insult and

surgery and major non-vascular sur- carries major morbidity and mortality.

gery have not been described. We Early recognition and aggressive man-

have recently been involved in man- agement can minimise subsequent mor-

aging a patient who had a combined tality [4]. Ivor Lewis oesophagectomy is

endarterectomy and oesophagectomy, associated with fewer anastomotic com-

and we would like to highlight several plications than the transhiatal approach

issues.

[5]. A combined operation increases the

A 58-year-old man was diagnosed risks; however, carotid surgery com-

with an operable adenocarcinoma of the bined with CABG has been described as

gastro-oesophageal junction. He was a safe technique and can decrease the

referred for neoadjuvant chemotherapy incidence of stroke and long-term mor-

prior to oesophagectomy. He described bidity [6, 7]. It is speculated that to have

symptoms of dizziness, tinnitus and a patent carotid artery is a beneﬁcial

intermittent temporary visual ﬁeld loss. protective factor before major surgery.

An urgent carotid Doppler showed Our patient responded well to the

bilateral severe stenosis, more on the neoadjuvant therapy [8] and delaying

left side. A left carotid endarterectomy the oesophagectomy would increase the

was performed 2 months later under possibility of metastatic spread. It is

general anaesthesia with an uneventful important to take all patient speciﬁc

recovery. He was then scheduled for a factors into consideration [9].

R. E. Self

S. V. Mallett

combined oesophagectomy and right

carotid endarterectomy.

In this case, the patient beneﬁted from

reduced risks of neurological events

Royal Free Hospital,

London NW3 2QG, UK

A thoracic epidural and left radial occurring during major surgery, while

arterial line was inserted prior to induc- avoiding delaying the oesophagectomy,

tion of general anaesthesia, the trachea which might have reduced his chances of

was intubated with a RAE tube and a curative procedure. Such combined

anaesthesia was maintained with O₂, procedures can be safely undertaken with

References

1

Favaloro E. Clinical applications of

the PFA-100Ò. Current Opinion in

Hematology 2002; 9: 407–15.

N O, and isoﬂurane. Laparoscopy was appropriate resources.

2

6

04

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Anaesthesia, 2003, 58, pages 597–616

Correspondence

....................................................................................................................................................................................................................

.

S. Rassam

Spontaneous reversal of the

‘wall effect’: another possible

PaO values. Though we assumed that

2

the tip of the sensor might be touching

C. Littler

L. Gemmell

cause for inaccurate continuous the wall of the artery, we did not change

Wrexham Mealor Hospital,

Wrexham LL13 7TD, UK

E-mail: ssrassam@ukonline.co.uk

intra-arterial blood gas

monitoring data

the position of the sensor because the

reconstruction surgery involving the

stomach had already started and the left

arm of the patient was not easily access-

ible. While the reconstruction involving

the stomach was being performed, we

found that the PaO₂values on the

CIABG monitor increased linearly for

approximately 20 min, even though no

ventilation setting had been changed.

The Paratrend 7 + CIABG monitor can

document either the arterial blood gas

data that are calibrated to ABL or data

that are not calibrated to ABL. There-

fore, both calibrated and uncalibrated

arterial blood gas data were displayed and

recorded on the CIABG monitor every

time arterial blood gas samples were

drawn for analysis. When the rise in

PaO₂was equilibrated, the PaO₂as

measured by ABL was much lower

The ‘wall effect’ is known to be one

possible cause of inaccurate continuous

intra-arterial blood gas (CIABG) mon-

References

1

Gunawardena ID, Burnett A, Make-

ham V, Harris JP. Why do some

patients with > 80% stenosis of the

internal carotid artery not undergo

surgery? A retrospective review.

itoring data, where PaO values are

2

underestimated due to the intra-arterial

sensor touching the arterial wall [1]. We

recently encountered a spontaneous

Australian New Zealand Journal of Surgery reversal of the ‘wall effect’, which

001; 71: 659–61.

caused an overestimation of PaO

Levinson MM, Rodriguez DI.

A 53-year-old, 162 cm, 52 kg, male

Endarterctomy for preventing stroke in patient, was scheduled to undergo

2

.

2

symptomatic and asymptomatic caro-

tid stenosis. Review of clinical trials

and recommendations for surgical

therapy. Heart Surgery Forum 1999; 2:

oesophagectomy under thoracoscopy.

After an epidural tube was inserted,

anaesthesia was induced with propofol

160 mg and was maintained with sevo-

ﬂurane. Tracheal intubation was facili-

tated by the addition of vecuronium

10 mg. A 37 Fr, left-sided, double-

lumen tracheal tube (Broncho-CathÒ,

Mallinckrodt Inc., Argyle, NY) was

placed and the accuracy of the position

1

47–68.

3

4

Feasby TE, Quan H, Ghali WA. Pro-

vincial carotid endarterectomy out-

comes. Canadian Journal of Neurological

Sciences 2002; 29: 333–6.

(219 mmHg) than the calibrated CIABG

value (337 mmHg) but was closer to the

uncalibrated CIABG data (210 mmHg),

which was not affected by calibration to

Griffin SM, Shaw IH, Dresner SM.

Early complications of Ivor Lewis sub- conﬁrmed by auscultation and by ﬁbre-

the ABL gas analyser. The PaO data on

2

total oesophagectomy with two-field

optic bronchoscopy. The patient’s lungs

were ventilated with an inspiratory

management. Journal of American College oxygen fraction of 0.5, a tidal volume

the ABL analyser were closer in value to

the uncalibrated CIABG data, except

when the PaO₂values were higher

during one-lung ventilation. Thereafter,

the ABL analyser PaO₂values were

lower than the calibrated CIABG data

lymphadenectomy: risk factors and

of Surgeons 2002; 194: 285–97.

Rindani R, Martin CJ, Cox MR.

Transhiatal versus Ivor Lewis

of 510 ml, and a respiratory rate of 8–10

during two-lung ventilation. An intra-

arterial sensor of the CIABG monitor

5

6

Oesophagectomy: Is there a difference? (Paratrend 7 + TM, Diametrics Med-

(

Table 1).

Australian and New Zealand Journal of ical Limited, High Wycombe, UK) was

inserted through a 20-gauge catheter

Surgery 1999; 69: 187–94.

Bonardelli S, Portolani N, Tiberio GA placed in the left radial artery and

Table 1 Sequential changes in PaO2

rnmHg) data measured by conventional

(

et al. Combined surgical approach for

carotid and coronary stenosis. Sixty-

four patients and review of literature.

advanced to a length of 15 cm. No

resistance was felt during the insertion

of the sensor. The arterial pressure wave

blood gas analyser (ABL 720) and Para-

trend 7± with and without calibration.

Journal of Cardiovascular Surgery 2002; was not damped after sensor insertion.

3: 385–90.

As is usually done in our institution,

Char D, Cuadra S, Ricotta J et al. Com- 2 ml of arterial blood was drawn for

bined coronary artery bypass and carotid

sensor calibration after tic marks on the

endarterectomy: long term results. Cardio- display conﬁrmed that the CIABG data

vascular Surgery 2002; 10: 111–15.

were ready for calibration. The arterial

Doty JR, Salazar JD, Forastiere AA, Heath blood gas data displayed on the CIABG

Paratrend Paratrend

4

7

±

7±

7

8

with

without

ABL 720 calibration calibration

1

0:12 (T)

252

165

Calibration

1

1:41 (T)

2:51 (O)

219

92

337

146

285

345

496

304

234

192

210

88

EI, Kleinberg L, Heitmiller RF. Postoe-

sophagectomy morbidity, mortality, and

length of hospital stay after preoperative

monitor (PaO 165 mmHg, PaCO

2 2

38.2 mmHg, pH 7.45) were calibrated 13:45 (O) 208

181

224

297

207

148

120

to the arterial blood gas data analysed

ABL 720TM (Radiometer,

Copenhagen, Denmark) (PaO

Ommer A, Toenissen C, Pillney M et al. 252 mmHg, PaCO

1

2

5:17 (O) 241

6:33 (O) 388

8:05 (O) 250

chemoradiation therapy. Annals of Thoracic by

Surgery 2002; 74: 227–31.

2

0:10 (T)

155

9

2

33.5 mmHg, 20:45 (T) 129

Surgical reconstruction of high grade

carotid stenosis: a safe procedure?

Chirurg 2002; 73: 481–6.

pH 7.469). We immediately noticed

the large difference between the CIABG (T) = two-lung ventilation.

and the ABL analyser (O) = one-lung ventilation.

monitor PaO

2

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2003 Blackwell Publishing Ltd

605

Correspondence

Anaesthesia, 2003, 58, pages 597–616

....................................................................................................................................................................................................................

.

The ‘wall effect’ is usually manifested

oxygenation during one-lung anaes-

thesia is related to the response to

compression of the non-dependent

There was no skin rash evident. She had

obvious macroglossia, with bloodstained

secretions on her pillow, and she was

by PaO₂values displayed on the

CIABG monitor that gradually decrease

with time but which are not accom-

lung. British Journal of Anaesthesia 2003; stridulous. On air, her SpO remained

2

panied by changes in either PaCO or

90: 21–6.

pH values [1]. Although the phenom- 5 Ishikawa S, Ohmi S, Nakazawa K,

above 92%, with a pulse rate of

2

)

1

70 beat.min , and BP 108 ⁄ 55 mmHg.

There was no bronchospasm on auscul-

tation, and no evidence of heart failure.

In view of her airway compromise and

enon was rarely seen in our total clinical

experience of over 200 cases, the ‘wall

effect’ is considered to be one of the

major causes of inaccurate CIABG data.

In our previous research, speciﬁcally

involving a total of 28 oesophagec-

tomy patients [2–4] and 50 patients who

underwent thoracotomy [5], the ‘wall

effect’ was never observed.

Makita K. Continuous intra-arterial

blood gas monitoring during thoracic

surgery. Journal of Anesthesia (Ofﬁcial

Journal of the Japan Society of Anesthesi- ﬂuctuating GCS, the patient was trans-

ology) 2000; 14: 119–23.

ferred to the ICU, where an anaesthetic

machine was available for inhalational

induction of anaesthesia.

Once on the ICU, further intraven-

ous access was secured, together with

invasive arterial BP monitoring. During

this period, nebulised epinephrine

(5 ml, 1 : 1000) was administered, with

immediate improvement in her airway.

The degree of macroglossia improved

enough to allow speech. Humidiﬁed O₂

was continued, and hydrocortisone and

antihistamines, both type 1 (H1) and

type 2 (H2), given. She was not intu-

bated, and remained stable over the

next 8 h with adequate arterial oxygen

saturations, and arterial blood gas ana-

lysis showing normal acid-base balance

with good gas exchange. She was

discharged to a medical ward with no

further compromise. Her macroglossia

gradually settled.

Potassium permanganate is regularly

used in the management of suppurative

eczema, and ulcers, and has previously

been used as an abortifacient. Ingestion

of dilute solutions can cause brown

staining of the mouth and throat, sore

throat, abdominal pains, vomiting and

dysphagia. Concentrated solutions, or

dry crystals as in this case, can cause

swelling and bleeding of lips and

tongue, pharyngeal oedema and swell-

ing of the larynx, as well as gastrointes-

tinal burns. Systemic effects do not

usually manifest, due to poor absorb-

ance, but can include tachycardia,

hypotension, hallucinations, methaem-

aglobinaemia and cyanosis, metabolic

acidosis, haemolysis, pancreatitis and

coma [2, 3]. Some effects can

be delayed up to 36 h postingestion

including disseminated intravascular

coagulation (DIC), cardiac failure and

hepato-renal failure. In 1996, Young

et al. postulated that the damage from

Airway obstruction following

potassium permanganate

ingestion

Since the PaCO and the pH data

2

were unaffected in this case, we assumed

that the ‘wall effect’ occurred when the

ﬁrst arterial blood sample was drawn for

calibration. The subsequent linear in-

Potassium permanganate (KMnO ) is a

4

highly corrosive, water-soluble oxid-

izing antiseptic for cleansing and

deodorizing suppurative eczematous

reactions and wounds, used in baths

and wet bandages. It is presented as a

crease in PaO on the CIABG monitor

2

might be explained by the reversal of the

‘

wall effect’, although it would be very

difﬁcult to prove this hypothesis. As far as

we know, a spontaneous reversal of the

0

.1% solution, diluted 10 times to yield

a 0.01% solution, or crystals that are

dissolved, and applied until the skin

becomes dry [1]. Both the crystals and

concentrated solutions are caustic to

skin, eyes, upper respiratory tract and

mucous membranes, resulting in coagu-

lation necrosis.

An 81-year-old woman was admitted

to Accident and Emergency following

deliberate ingestion of an unknown

‘

wall effect’ has not been previously

reported. This case suggests that a ‘wall

effect’ reversal can occur spontaneously

and that it may cause the CIABG mon-

itor to overestimate PaO values, espe-

2

cially when the CIABG data has

been calibrated to an arterial blood gas

analyser.

S. Ishikawa

K. Nakazawa

amount of KMnO crystals, which were

4

K. Makita

being regularly applied to suppurative

chronic leg ulcers. She had a history of

heart failure, chronic renal failure and

atrial ﬁbrillation, for which she was

receiving warfarin. She had refused oral

ﬂuid replacement on admission and

Tokyo Medical and Dental University,

Tokyo 113–8519, Japan

E-mail: ishikawa.mane@tmd.ac.jp

References

1

2

3

Mahutte CK, Sassoon CSH, Muro JR, intravenous replacement was started.

et al. Progress in the development of a She remained cardiovascularly stable

fluorescent intravascular blood gas sys-

without respiratory compromise and

tem in man. Journal of Clinical Monitoring her SpO remaining above 92% on air.

2

1

990; 6: 147–57.

She was also commenced on intraven-

ous antibiotics for presumed incidental

cutaneous infection.

Twelve hours after admission, I was

asked to review the patient on the ward,

because she had a reduced level of

Ishikawa S, Makita K, Nakazawa K,

Amaha K. Continuous intra-arterial

blood gas monitoring during

oesophagectomy. Canadian Journal of

Anaesthesia 1998; 45: 273–6.

Ishikawa S. Oxygenation may improve consciousness and was snoring. The

with time during one-lung ventilation. nursing staff also noticed that her tongue

Anesthesia and Analgesia 1999; 89:

58–9.

had swollen in the preceding hour. On

initial assessment, she was rousable with

a Glasgow coma scale (GCS) of 11. She

was afebrile, pale, with cool peripheries.

2

4

Ishikawa S, Nakazawa K, Makita K.

Progressive changes in arterial

ingestion of KMnO crystals was due to

4

6

06

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.

oxidative injury from free radicals gen- 3 h prior to referral, so an allergic reac-

taking it for charcoal. Das Deutsche

erated by the absorbed permanganate tion could not be excluded, although,

Gesundheitswesen 1967; 22: 897–9.

ion. They found that the clinical course aside from an enlarged tongue, there 6 Drug Information. ToxbaseWebsite at

following KMnO₄poisoning closely were no other manifestations of allergy.

resembled severe paracetamol overdose, Secondary therapy with steroids and

and recommended early administration antihistamines was started but, as

http://www.spib.axl.co.uk/Toxbase.

Progressive external

of N-acetylcysteine [4].

KMnO₄can cause gastro- intestinal

ophthalmoplegia and

ambulatory remifentanil-

propofol based anaesthesia

The fatal dose for an adult is 10 g, and burns and inﬂammation, histamine 2

death usually results from pharyngeal receptor blockers and steroids also have

oedema and cardiovascular collapse. a role following its ingestion. The patient

Current treatment guidelines include was discharged from ICU after close

avoidance of gut decontamination, and monitoring for 8 h with no sequelae.

With the advent of modern technology,

new diseases are described. As patients

with these ‘new’ conditions may

require surgical procedures, the anaes-

thetic implications need to be addressed

liberal oral ﬂuids unless perforation is

Potassium permanganate is a com-

suspected. Indeed, there has been a monly used antiseptic with astringent

documented case of fatal poisoning when properties, although many anaesthetists

charcoal was mistaken for KMnO [5]. have probably not encountered it since

4

[

1]. Mitochondrial myopathies are dis-

Supportive treatment is the mainstay of growing crystals in chemistry classes at

treatment thereafter, and if stable after school. It can cause severe caustic damage

orders of fatty acid utilisation or mitoch-

ondrial function that may affect skeletal

muscle, or defective aerobic metabolism

that effect several organ systems. The

CNS is often affected. Other organs

affected include the heart, liver, kidney,

endocrine glands and gastro-intestinal

tract [2].

We present a 61-year-old woman,

weight 69 kg, height 160 cm, sched-

uled for breast biopsy. Her family

history included maternal myasthenia

gravis. Her medical history included

hypothyroidism of unknown aetiology

treated with thyroxine 50 mg daily, and

deafness that needed a tympanoplasty.

She was diagnosed as having progres-

sive external ophthalmoplegia (PEO)

2 months before surgery because of

recent and progressive bilateral ptosis.

Muscular biopsy showed ragged red

ﬁbres and subsarcoleme lipofucsine

2

h

following ingestion of dilute to the airway when ingested. As anaes-

solutions, further treatment is unneces- thetists, relief of airway obstruction is one

sary [6]. -acetylcysteine should, how- of our primary roles, both in theatre and

N

ever, be given within the ﬁrst few hours, on the intensive care unit (ICU), whe-

in the same dose as used in paracetamol ther due to upper airway, mid or lower

poisoning.

tracheal, or bronchial obstruction. Occa-

This patient was reviewed 12 h after sionally, the anaesthetist can encounter

initial presentation and had not received an unusual agent as the cause of obstruc-

N

-acetylcysteine, but had been stable tion, but airway management should not

until 1 h before referral. Stridor is be inﬂuenced by this unfamiliarity.

characteristic of upper airway obstruc-

R. S. Dhamrait

tion, and suggests at least 50% reduction

Southampton General Hospital,

in airway diameter. Its presence,

Southampton SO16 6YD, UK

together with an inability to swallow

E-mail: rajdhamrait@hotmail.com

secretions, should be a warning of

severe airway compromise, and further

management is dependent on patient

References

1

2

British National Formulary, Sept. Phar-

maceutical Press, London 2002: 584.

Mahomedy MC, Mahomedy YH,

Canham PA, Downing JW, Jeal DE.

factors and the skill of the anaesthetist.

In an expected difﬁcult intubation, an

awake ﬁbreoptic intubation may be

indicated but the presence of secretions,

including blood, may make this techni-

cally difﬁcult. Inhalational induction

with sevoﬂurane in oxygen allows

intubation in a spontaneously breathing

patient, and in the event of a failed

intubation allows emergency tracheos-

tomy in the anaesthetised patient. In this

case, the patient was transferred to the

ICU, where there is always a pre-

checked cylinder-driven anaesthetic

machine with sevoﬂurane available.

Epinephrine was started as a temporary

measure but resulted in a signiﬁcant

improvement and, with stable SpO₂,

satisfactory blood gas measurements and

a talking patient, it was felt that intuba-

tion was not required. She had also

received a dose of intravenous antibiotics

Methaemaglobinaemia following treat- granules. Lactic acid levels were high

ment dispensed by witch doctors. Two after exercise and 55 min after cessation.

cases of potassium permanganate poi-

No therapeutic recommendations were

made. Pre-operative haematology, bio-

Middleton SJ, Jacyna M, McClaren D, chemistry and ECG were normal.

Robinson R, Thomas HC. Haemor-

We planned an anaesthetic technique

rhagic pancreatitis – a cause of death in avoiding triggers for malignant hyper-

soning. Anaesthesia 1975; 30: 190–3.

3

4

5

severe potassium permanganate poi-

thermia (MH), potential respiratory

complications and with the initial plan

of keeping the patient in an ambulatory

surgery setting. Monitoring was: ECG,

soning. Postgraduate Medical Journal

1

990; 66: 657–8.

Young RJ, Critchley JA, Young KK,

Freebairn RC, Reynolds AP, Lolin YI. non-invasive blood pressure (NIBP),

Fatal acute hepato-renal failure follow- pulse oximetry, capnography and oeso-

phageal temperature. Dantrolene was

Human Experimental Toxicology 1996; immediately available. The ventilator

ing potassium permanganate ingestion.

1

5: 259–61.

was previously purged with high ﬂow

oxygen. An intravenous saline infusion

was started. Pre-anaesthetic medication

Justus J, Gastmeier G. Fatal potassium

permanganate poisoning due to mis-

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2003 Blackwell Publishing Ltd

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Anaesthesia, 2003, 58, pages 597–616

....................................................................................................................................................................................................................

.

consisted of i.v. midazolam 1.5 mg, aged with regional anaesthesia have

followed by a remifentanil infusion rate been described in patients with MM

biochemical and genetic an a´ lisis

(9 cases). La Revue de Medecine Interne

of 0.25 lg.kg ⁾.min Induction was [6].

1

)1

1996; 17: 200–6.

performed with propofol 140 mg and a

Ambulatory care surgery is possible in 4 Karabiyik L, Parpucu M, Kurtipek O.

laryngeal mask size 3 was inserted. PEO patients, as possible for many

Anaesthesia was maintained with a other conditions whose MH suscepti-

mixture of oxygen and nitrous oxide bility is low and a non-triggering tech-

with a remifentanil infusion and assisted nique is used. Total intravenous

manual ventilation until spontaneous anaesthesia (TIVA) based on propofol

Total intravenous anaesthesia and the

use of an intubating laryngeal mask in a

patient with osteogenesis imperfecta.

Acta Anaesthesiologica Scandinavica 2002;

46: 618–19.

ventilation started after 5 min. Duration and alfentanil has been used successfully 5 Wootton MA, Lockie J. Anaesthetic

of surgery was 40 min and the remif- for eye surgery [7], or ketamine with

entanil infusion and nitrous oxide were fentanyl for cardiac surgery [8].

management of a child with a positive

family history of malignant hyperther-

mia for posterior fossa surgery in the

sitting position. Paediatric Anaesthesia

2001; 11: 498–500.

discontinued at the completion of skin

suturing. The patient awoke within continues to grow and increases the

min. The total dose of remifentanil likelihood of encountering MH-

The use of ambulatory care surgery

5

was 0.39 mg. At the end of surgery the susceptible patients or of experiencing 6 Martinez-Ubieto J, Gomez Gomez R,

Ruiz Tramazaygues J, Quesada

patient was transferred to the recovery a malignant hyperthermia crisis. The

unit for 1 h and discharged home 6 h management of this population creates

Gimeno N, S a´ nchez Tirado JA,

Herranz Andres P. Anestesia

later.

new challenges A comprehensive plan of

Mitochondrial myopathies (MM) are patient care under these circumstances

classiﬁed according to their histological includes the ability to identify the high-

appearance, inmunochemical and bio- risk patient and to plan their care accord-

subaracnoidea en un caso de miopat ´ı a

mitocondrial. Revista Espanola de Anes-

tesiologia Y Reanimacion 2001; 48: 196.

chemical proﬁle or genetic analysis. The ingly, early recognition of the signs and 7 Wisely NA, Cook PR. General

histological hallmark of MM is the symptoms of MH, and being prepared to

ragged red ﬁbre. PEO is associated with promptly and efﬁciently treat a malignant

sporadic deletions of DNA. A negative hyperthermic event [9].

anesthesia in a man with mitochondrial

myopathy undergoing eye surgery.

European Journal of Anesthesiology 2001;

18: 333–5.

family history indicates that deletion

MM is an heterogeneous group of

occurs in embryogenesis. Age of pres- rare conditions that will need to be 8 Sharma AD, Erb T, Schulman SR,

entation ranged from 47 to 82 years in a anaesthetised more often in future and

nine-case series [3], with asymmetrical we believe that new anaesthetic drug

ptosis as the commonest sign, as in our combinations offer the patient safe

patient. In this series, CPK was normal anaesthesia with low MH risk and allow

in eight cases and myopathic changes ambulatory surgery to be possible.

Sreeram G, Slaughter TF. Anaesthetic

considerations for a child with com-

bined Prader-Willi syndrome and

mitochondrial myopathy. Paediatric

Anaesthesia 2001; 11: 488–90.

were found in three cases. The clinical

E. Guasch

9 Karlet MC. Malignant hyperthermia:

considerations for ambulatory surgery.

Journal of Perianesthesia Nursing 1998;

13: 304–12.

course is usually progressive and diabe-

B. Civantos

tes mellitus, hypothyroidism, hyperpara-

J. M. Aguilar

thyroidism and short stature are often

M. D. Torres

associated.

F. Gilsanz

The anaesthetic implication in MM

2

8700-Madrid, Spain

and PEO is an increased susceptibility

for MH, which has been described in

at least one case. This requires a non-

triggering anaesthetic technique. This

can be addressed with propofol and

remifentanil infusions [4, 5]. Depressed

ventilatory response to hypercarbia or

hypoxia, independent of muscle weak-

ness or sleep apnoea, has been des-

cribed in patients with various MMs

including PEO [2]. Marked sensitivity

to intravenous induction agents, opi-

ates or sedative-hypnotics may be pre-

sent and weaning difﬁculty has been

described.

E-mail: emiguasch@hotmail.com

Postoperative respiratory arrest

in a post poliomyelitis patient (1)

References

1

Thompson VA, Wahr JA. Anesthetic

considerations in patients presenting

with mitochondrial myopathy, ence-

phalopathy, lactic acidosis and stroke

I read with interest this report of a

patient who had had poliomyelitis and

developed postoperative respiratory fail-

ure (Magi et al. Anaesthesia 2003; 58:

like episodes (MELAS) syndrome. An- 98–9). This should always be considered

esthesia and Analgesia 1997; 85: 1404–6. a potential complication when polio-

Miller JD, Rosenbaum H. Muscle dis- myelitis has affected the respiratory

eases. In: Benumof WB, ed. Anesthesia muscles [1]. It is important to ascertain

2

3

and Uncommon Diseases, 4th edn,

in the pre-operative assessment whether

or not these were involved in the acute

Drouet A. Chronic progressive external illness, and in particular whether respir-

Philadelphia: Saunders, 1998: 345–8.

ophthalmoplegia with mitochondrial

anomalies. Clinical, histological

atory support, usually in the form of an

iron lung, was required.

A few cases of pregnancy and other

surgical procedures successfully man-

6

08

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.

The subject of this report had recur-

hypoventilation. Quarterly Journal of

Medicine 1976; 45: 87–100.

the early postoperative period after

short operations [1, 2] when moving

the patient off the table or onto her

bed causes a surge of drug back into

the circulation. This increases the

danger of respiratory depression, par-

ticularly if coinciding, as is often the

case, with the onset of effect from a

slower acting opioid such as mor-

phine, given in this case subcutane-

ously ‘during the procedure’.

3 We are not clear why she was also

given atracurium ‘for intubation and

maintenance of relaxation’. We assume

that as her operation was elective she

was adequately starved, and she was not

having an abdominal or thoracic pro-

cedure. We would not regard either

intubation or relaxation as indicated,

even for a ﬁt patient in this case. Again,

for a brief procedure a competitive

neuromuscular blocking drug introdu-

ces yet another postoperative hazard.

Whatever happened to the KISS prin-

ciple in modern anaesthesia? (Keep it

simple, stupid!)

4 Postoperatively she was left ‘in her

room’ unmonitored for 50 min. Can

this now ever be regarded as safe

practice after general anaesthesia?

In 1990 we described in this journal

the guiding principles that led to

successful conduct of anaesthesia for

142 operations of all grades in 83

patients with restrictive respiratory dis-

ease, 44 of whom had had poliomye-

litis [3]. Nostra culpa that neither the

key words nor the abstract mentioned

poliomyelitis.

rent headaches, probably due to noc-

turnal hypoventilation. This arises

particularly during rapid eye movement

(

REM) sleep, which occurs mainly at the

Postoperative respiratory arrest

in a post poliomyelitis patient (2)

end of the night. The headaches are

characteristically bifrontal, occur early in

the morning and clear within 20–30 min

of waking. The authors comment on

other ‘vague’ symptoms such as somno-

lence but this is a characteristic feature

of nocturnal hypoventilation. The

repetitive respiratory related arousals

fragment sleep signiﬁcantly to lead to

the sensation of waking feeling

unrefreshed and of excessive daytime

sleepiness.

While measurement of respiratory

muscle strength may be of value, a

simpler and much more widely available

screening test for chest wall muscle

involvement is the vital capacity. This

should be carried out in the supine as

well as the sitting position in order to

detect bilateral diaphragmatic weakness,

which may only be apparent from the

fall in vital capacity of up to 50% while

lying ﬂat [2]. If the clinical features

and the vital capacity of less than

We were distressed to read the letter

describing a patient who suffered severe

hypoxic brain damage following an

operation on her foot (Magi et al.

Anaesthesia 2003; 58: 98–9).

We consider a number of factors

contributed to this unfortunate outcome:

1

The pre-operative assessment

failed in its prime purpose, to identify

risk factors for anaesthesia; it was not

lack of knowledge of polio but of

respiratory function that was the prob-

lem. Even minor physical disability may

conceal exertional dyspnoea, yet we

suspect the indicators were there. The

patient suffered from headaches that

were sufﬁciently serious to be noted

pre-operatively, yet their cause was not

considered. They were simply regarded

as a contra-indication to spinal anaes-

thesia, though the logic of this escapes

us. (Would you avoid antibiotics in the

treatment of cholera because they

themselves sometimes cause diarrhoea?)

We assume that they were mainly

morning headaches, provoked by noc-

turnal hypoventilation. Respiratory

insufﬁciency would also have been

detectable in a quiet voice and tachyp-

noea during speech. The authors made

the correct diagnosis in retrospect, but

there would have been no need for

blood gas analysis, a simple vital capacity

measurement is all that is needed to

identify restrictive respiratory disease,

particularly in association with headache.

1

.0–1.5 litres suggest signiﬁcant respir-

atory involvement, arterial blood gases

should be measured pre-operatively and

non-invasive ventilation, usually in the

form of nasal or oro-nasal mask venti-

lation, should be available postopera-

tively. The risk of hypoventilation can

be reduced by avoiding muscle neuro-

muscular blocking agents during surgery

and only discontinuing mechanical

ventilatory support when the effect of

the anaesthetic agents has completely

worn off.

This report does highlight the risks of

those who have had poliomyelitis when

they undergo surgery, but accurate

assessment pre-operatively can usually

prevent postoperative complications

•

Pre-operative care included careful

assessment, with training, if needed,

in the use of non-invasive methods of

respiratory support, which may be

necessary during recovery from anaes-

thesia even among those not hitherto

dependent on it.

2

As those concerned with anaes-

thesia in this case overlooked respirat-

ory insufﬁciency, it is perhaps to be

expected that the danger of a respir-

atory depressant drug in these circum-

stances was also overlooked. The

administration of three different opi-

oids during brief surgery can only

have compounded the problem. Rem-

ifentanil may be ultra-short acting, but

then why also give fentanyl ) 0.1 mg

no less? The pharmacokinetic charac-

•

Competitive depolarizing muscle

relaxants were not used (though it

was often necessary to assist the

patient’s respiratory effort by hand),

not because of any expectation of

abnormal sensitivity, but because they

were unnecessary and would increase

the postoperative risk.

J. M. Shneerson

Papworth Hospital,

Cambridge CB3 8RE, UK

References

1

2

Sheerson JM. Disorders of Ventilation.

Oxford: Blackwell Scientiﬁc Publica-

tions, 1988: 139–43.

•

Opioids were kept to a minimum and

used in small doses for postoperative

analgesia only.

Davis JN, Goldman M, Loh L, Casson teristics of fentanyl have long been

M. Diaphragm function and alveolar

known to pose a particular danger in

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Anaesthesia, 2003, 58, pages 597–616

....................................................................................................................................................................................................................

.

•

The recognised dangers of the post- Spencer [3] are related to overt respir- Convulsions following axillary

operative period mandated special atory failure and major disability. In our brachial plexus blockade with

attention to respiratory function.

patient and in the case described by levobupivacaine (1)

Gaul [5], the respiratory failure was

occult; our conclusion is that every We read with interest the case report of

patient with previous poliomyelitis has convulsions following axillary brachial

Every one of the simple measures that

we recommended for patients with

restrictive respiratory disease was inad-

vertently transgressed in this case.

The condition of patients who have

once had polio may deteriorate in later

life, not only because of any so-called

post-polio syndrome, but for a variety

of reasons largely connected with

ageing [4].

to be evaluated in this regard.

plexus blockade with levobupivacaine in

In cases of suspected occult respirat- an anaesthetised patient (Pirotta &

ory failure, we also have to consider Sprigge. Anaesthesia 2002; 57: 1187–9).

primary hypoventilation and sleep The authors postulate that the con-

apnoea syndrome as possible causes, so vulsions were probably due to an inad-

we cannot limit our investigations to vertent intravascular injection of

the vital capacity, and at least blood gas levobupivacaine and with that we concur

analysis is required.

completely. The use of levobupivacaine

G. T. Spencer

We totally agree with the idea that with a better cardiovascular safety proﬁle

the anaesthetic technique has to be than traditional agents may have preven-

simple and that we have to minimise ted more serious consequences, but the

the use of opioids and neuromuscular practice of a safe technique remains

blocking agents. Cases like this remind paramount.

Formerly Clinical Director,

the Lane-Fox Respiratory Unit,

F. Reynolds

Emeritus Professor of Obstetric

Anaesthesia

us that in our practice we may

We use a different technique to block

St Thomas’ Hospital,

London, UK

encounter patients with occult disease the axillary plexus than that described

that can expose them to abnormal and believe that our technique confers

responses to standard doses of anaes- some signiﬁcant safety advantages. The

E-mail: felicity.reynolds@

btinternet.com

thetic drugs.

multi injection technique described by

Coventry et al. [1] uses a peripheral

nerve stimulator and a starting current

of 2 mA ) the reported starting current

of 5 mA seems rather high and will

cause muscle twitching when the needle

is some distance from the nerve. The

authors then began injecting levobupi-

vacaine when the twitch disappeared at

E. Magi

C. Recine

A reply

B. Klockenbusch

A. Cascianini

We are grateful for the opportunity to

reply to the comments by Reynolds and

Spencer on our recent letter.

The patient we described was a

Hospital S. Donato,

Arezzo, Italy

E-mail: eziomagi@libero.it

5

1-year-old woman who had poliomy-

elitis since 2 years of age, without chest

deformities, major motor deﬁcits or

respiratory symptoms; her status was 1 Adams AP, Pybus DA. Delayed respir-

1

mA; again, this still may be some

References

distance from the nerve and it is our

current practice to locate the nerve and

maintain a twitch at 0.5 mA. Patience is

a virtue with this technique but Cov-

entry et al. report a success rate of 97%

with the multi injection technique as

opposed to 53% with a single injection

technique.

It appears from the article that the

authors began injecting when there was

no twitch present. This is contrary to

our practice, as we would only inject

when the twitch was present; if imme-

diate abolition of the twitch did not

occur, we would stop injecting, as this is

a sign of possible inadvertent intravas-

cular injection. Negative aspiration does

not guarantee the absence of intravas-

cular needle placement.

classiﬁed ASA 2. We cannot add more

details because although she was admit-

ted to our intensive care unit, we were

atory depression after use of fentanyl

during anaesthesia. British Medical

Journal 1978; 1: 278.

not involved in the pre-operative assess- 2 McQuay HJ, Moore RA, Paterson

ment or anaesthesia. We therefore can-

not comment on whether her

respiratory problems could have been

better assessed. Headache is a very

common complaint and it is very

GMC, Adams AP. Plasma fentanyl

concentrations and clinical observations

during and after operation. British

Journal of Anaesthesia 1979; 51:

543–50.

improbable that it could be considered 3 Patrick JA, Meyer-Witting M,

as a possible symptom of respiratory

failure during a routine pre-operative

assessment of an apparently healthy

patient. Patients who suffer recurrent

Reynolds F, Spencer GT. Peri-

operative care in restrictive

respiratory disease. Anaesthesia 1990;

45: 390–5.

headaches are reluctant to accept a 4 Howard RS, Wiles CME, Spencer GT.

technique such as subarachnoid anaes-

thesia when told that headaches are a

complication.

The late sequelae of poliomyelitis.

Quarterly Journal of Medicine 1988; 66:

219–32.

Using the multi injection technique,

the total volume of local anaesthetic is,

of course, split between different sites,

potentially decreasing the dose injected

intravascularly at any particular site and

The anaesthetic risk and the respirat- 5 Gaul C, Winterholler M. Post polio

ory problems in patients with previous

poliomyelitis described in the literature

and in the article cited by Reynolds and

syndrome and weaning failure 40 years

after the last polio epidemic. Anaesthetist

2002; 51: 378–82.

6

10

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Correspondence

....................................................................................................................................................................................................................

.

allowing a short time lag between each entirely due to opioid analgesia, it is A reply

dose for questioning the patient for any common sense to consider the cause of Thank you for giving us the oppor-

symptoms of intravenous injection. PONV in a woman undergoing gynae- tunity to reply to the comments of

Finally, the authors used a technique cological surgery under general anaes- Drs Cumming and Barker.

described by Brockway and Wildsmith thesia to be multifactorial.

We acknowledge that other tech-

2]. Professor Wildsmith is vocal in his Secondly, there does not seem to be a niques to block the brachial plexus by

support of performing blocks in awake good reason for not performing the the axillary route may offer advantages.

patients [3]. Again, this would have block awake.

The use of a starting current of 5 mA

conferred a safety beneﬁt in this case. Regarding the conduct of the block- may be rather high, as they suggest.

[

There may have been warning signs ade, commonly the initial current used This is quickly reduced in our practice

such as peri-oral tingling or tinnitus, is between 1 and 2 mA, facilitating the once a twitch is obtained. However,

which would have alerted the authors general location of the nerve, and then there is an argument for starting with a

and prevented them from injecting the reducing to 0.3–0.5 mA to ensure lower current. We do not feel that the

full dose.

close proximity to the nerve [1, 2]. amplitude of the starting current affects

The time when one would expect the the likelihood of intravascular injection.

twitches to disappear is after the injec- Ideally, twitch loss should occur with a

tion of the initial few millilitres of the lower current of around 0.5 mA as they

local anaesthetic. We do not see the suggest. This is not always possible to

logic in injecting local anaesthetic achieve, as was the case with our

when the twitches disappear at 1 mA patient. In any case, referral to the

and the needle-tip is probably posi- anatomy of the brachial plexus shows

tioned anywhere except in the vicinity that the axillary vein and its tributaries

of the nerve to be blocked! Further lie very close to the branches of the

evidence as to the distance between brachial plexus [3], so that it is not

the intended nerve and the position of inconceivable that the needle might

the local anaesthetic depot is suggested produce a twitch at 0.5 mA and still

by the fact that the block had com- be in a vein.

C. Cumming

K. Barker

Raigmore Hospital,

Inverness IV2 3UJ, UK

References

1

Coventry DM, Barker KF, Thomson

M. Comparison of two neurostimula-

tion techniques for axillary brachial

plexus blockade. British Journal of

Anaesthesia 2001; 86: 80–3.

2

3

Brockway MS, Wildsmith JAW. Axil-

lary brachial plexus block. method of

choice? British Journal of Anaesthesia

pletely worn off after only 4 h, a block

that, when performed optimally, should impression that injection started in the

last longer.

absence of twitches. This is in fact not

It appears we gave the incorrect

1

990; 64: 224–31.

Wildsmith JAW. Regional anaesthesia:

before or after general anaesthesia?

Anaesthesia 1999; 54: 86.

It is also helpful to disconnect the the case. Once the twitch is lost, the

syringe each time the needle is moved. current is increased slightly until muscle

This ensures that there is a free ﬂow of activity is recaptured. Then loss of

blood down the cannula (assuming that the twitch is witnessed secondary to

the immobile needle technique is used) injection of local anaesthetic as they

should one of the larger blood vessels be recommend.

Convulsions following axillary

brachial plexus blockade with

levobupivacaine (2)

punctured accidentally (commonly axil-

We agree that blocks should be

lary artery and vein) and helps remove performed in the awake patient when-

the problem of negative pressure appo- ever possible and we highlight this in

We read with interest the case report

involvinglevobupivacaine-inducedcon-

vulsions while performing axillary block

sition of smaller vessel walls.

our discussion. This is not always poss-

We would also like to point out the ible. In our case, we were concerned

miscalculation of the total dose of local that stimulation of muscles crossing the

anaesthetic as 125 mg instead of fracture site might have increased

112.5 mg. However, this does not patient discomfort. However, we

make a big difference in the interpret- acknowledge that this in itself is not

(

1

Pirotta & Sprigge. Anaesthesia 2002; 57:

187–9) and would like to make a few

comments regarding the conduct of the

regional block technique.

)1

ation of toxicity (1.61 mg.kg instead necessarily a contra-indication for per-

forming blocks in the awake patient.

)

1

of 1.78 mg.kg ).

Firstly, the main reason for performing

the axillary blockade seems to be the

avoidance of postoperative nausea and

vomiting (PONV). If that were the case,

it would have been prudent to avoid a

general anaesthetic altogether or at least

to avoid nitrous oxide and consider the

use of a total intravenous anaesthetic

technique instead of using an inhalational

anaesthetic agent up to 2 MAC.

Finally, we are interested to know Nevertheless, thousands of blocks are

whether the authors were successful in still performed in anaesthetised patients

achieving the aim of the blockade, in the UK each year.

namely avoidance of PONV!

We are grateful to Drs Dhileepan and

Davis for their comments about our

anaesthetic technique, which plainly was

not perfect. If it had been, our patient

would not have convulsed. As they

note, the previous episode of postoper-

S. Dhileepan

N. Davis

St George’s Hospital,

London SW17 0QT, UK

E-mail: dilsub@yahoo.com

Even though the patient had been

told the previous episode of PONV was

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.

ative nausea and vomiting (PONV) was

probably multifactorial and due to the 1 Wildsmith JAW, Armitage EN. Princi- through the greater sciatic notch.

References

lation of the sciatic nerve as it emerges

combination of the factors they high-

light. The avoidance of a general anaes-

thetic (GA) altogether would indeed 2 Choyce A, Chan VW, Middleton WJ

ples and Practice of Regional Anesthesia.

An alternative to peripheral nerve

stimulation of the femoral nerve is the

fascia iliaca block, which only requires

London: Churchill Livingstone, 1993.

have been the surest way to avoid

PONV. However, this is not always

possible. In order to avoid a GA, one

would have to be conﬁdent that the

block was sufﬁciently dense to allow

et al. What is the relationship between identiﬁcation of two fascial ‘clicks’. This

paresthesia and nerve stimulation for

has been shown to provide reliable and

effective analgesia within the femoral

Anesthesia and Pain Medicine 2001; 26: nerve distribution [2]. In particular, it

axillary brachial plexus block? Regional

100–4.

excludes the possibility of inadvertent

intraneural injection.

surgery to take place. This is by no 3 Gray’s Anatomy. Edinburgh: Churchill

means certain even in the best hands.

Livingstone, 1980: 753.

Furthermore, avoidance of GA 4 Pollard BJ, Elliot RA, Moore EW.

In the reported clinical situation, the

patient presented with toxaemia and

single shot peripheral nerve blocks were

entirely appropriate. In the absence of

sepsis, consideration should be given to

the use of peripheral nerve catheters,

which would provide excellent postop-

erative analgesia and reduce the expo-

sure of opioids that may exacerbate

acute confusion.

a

depends on our surgical colleagues being

happy to perform the surgery under such

conditions. Our orthopaedic surgeons

do not routinely perform this procedure

under regional anaesthesia alone.

They suggest that the patient’s sus-

ceptibility to PONV might have been

better served if total intravenous anaes-

thesia had been used. This may be so

Anaesthetic agents in adult day case

surgery. European Journal of Anaesthesi-

ology 2003; 20: 1–10.

Lower limb blocks following

general anaesthesia

In addition, ultrasound has been used

to aid nerve block placement for

femoral nerve [3] and posterior lumbar

plexus [4] blocks. Whilst this technique

may be useful, its use for sciatic nerve

blocks has not yet been described.

The ability of patients to report

directly the symptoms of intravascular

injection or intraneural needle place-

ment is reduced in the confused patient.

Alternative methods may aid the detec-

tion of these potential complications.

Intravascular injection may be identiﬁed

by the alteration of heart rate and ⁄ or

blood pressure following injection of an

epinephrine-containing solution [5]. In-

traneural injection may be identiﬁed by

a continued motor response with a low

stimulating current (< 0.25 mA) or by

marked resistance to injection.

We read with interest the letter con-

cerning lower extremity blocks in the

amputee (Lok & Kirk. Anaesthesia 2003;

[

4]. However, our patient did not

experience PONV. We acknowledge

our error in calculating the total dose of

local anaesthesia.

Drs Dhileepan and Davis also com-

ment that the detection of a twitch at

5

8: 289–90). The letter raises a number

of valid points: ﬁrst, the choice of

peripheral nerve block technique in

amputees, and second, the safety issues

surrounding regional techniques fol-

lowing the induction of general anaes-

thesia. We have been faced with similar

clinical situations on previous occasions.

In the co-operative amputee, we have

sought paraesthesia in the phantom limb

using either a needle or a peripheral

nerve stimulator with a high stimulating

current (> 1 mA). In the unco-opera-

tive patient, a response to paraesthesia

may be difﬁcult to elicit. However, a

motor response may be sought within

the remaining proximal limb. In this

case, we would suggest either a classic

Labat or a parasacral approach to sciatic

nerve block. During the classic sciatic

nerve block, the operator may stimulate

the hamstring muscles as a result of

either tibial nerve innervation or direct

hamstring stimulation with the needle.

The latter may fail to establish a satis-

factory block if not recognised during

block placement. If a piriformis con-

traction is elicited prior to the onset of

hamstring contraction, this is suggestive

of correct needle placement.

1

mA, but not less, is evidence that the

needle tip must have been in the wrong

place. We would argue that the needle

must have been quite close to the

brachial plexus, or there would not

have been a twitch. Of course we agree

that the needle was not in the right

place. If it had been, the incident would

not have occurred. The fact that the

block had worn off completely by 4 h

may be due to a signiﬁcant proportion

of the local anaesthetic having been

deposited intravascularly rather than

perineurally.

Our case report is anecdotal evidence

that when up to 125 mg levobupiva-

caine was injected intravascularly, the

effect was a transient convulsion without

any cardiovascular effect. It is unlikely

that there would have been such a benign

response with bupivacaine.

In conclusion, peripheral nerve

blocks can be used successfully in this

patient population.

D. MacLeod

S. Grant

D. Breslin

G. Martin

Duke University Medical Center,

Durham NC, USA

E-mail: david.macleod@duke.edu

D. Pirotta

Royal Liverpool University Hospital,

Liverpool L7 8XP, UK

E-mail: dap@davidpirotta.

freeserve.co.uk

References

1 Mansour NY. Reevaluating the sciatic

nerve block: another landmark for

consideration. Regional Anaesthesia

1993; 18: 322–3.

J. Sprigge

A parascaral approach [1] avoids direct

hamstring contraction. If a hamstring

contraction is obtained, it is due to stimu-

Arrowe Park Hospital.

Wirral CH49 5PE, UK

6

12

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....................................................................................................................................................................................................................

.

2

Capdevila X, Biboulet P, Bouregba M sustained second degree burns to his

Rowbotham DJ, Smith G, ed. Anaes-

thesia, Vol 2 ⁄ 68: Oxford: Blackwell,

1994: 1411–51.

et al. Comparison of the three-in-one

and fascia iliaca compartment blocks

in adults: clinical and radiographic

analysis. Anesthesia and Analgesia 1998;

thumb, index and ring ﬁngers.

Thermal injury from a hot drink

while under spinal or epidural analgesia 3 McMinn RM. Last’s Anatomy, 9th edn.

Edinburgh: Churchill Livingstone,

1994: 1(2), 18–23; 6(23), 574–5.

is an unusual mechanism of iatrogenic

injury. It is possible that the level of

86: 1039–44.

3

4

5

Marhofer P, Schrogendorfer K, Koinig sensory blockade may have been incor-

H et al. Ultrasonographic guidance

rectly evaluated. This could have been

improves sensory block and onset time due to the double innervation from the

Transient hearing loss with

labour epidural block

of three-in-one blocks. Anesthesia and

Analgesia 1997; 85: 854–7.

4th and5th cervical nerves along with the

upper thoracic nerves above the nipple

line. As the motor blockade characteris-

tically lags behind sensory blockade by

two segments [1, 2], power for lifting the

We report a case of transient bilateral

hearing loss with each top-up for an

otherwise uneventful epidural block for

pain relief in labour. Cranial nerve

palsies associated with epidural blockade

have been described in the literature,

especially of the trigeminal, abducens

and facial nerves [1]. Transient hearing

loss has been described in association

with accidental dural puncture, which

was successfully treated with autologous

epidural blood patch (AEBP) [2]. Deaf-

ness following spinal anaesthesia has

been cured with AEBP [3, 4].

Kirchmair L, Entner T, Kapral S,

Mitterschiffthaler G. Ultrasound

guidance for the psoas compartment

block: an imaging study. Anesthesia and cup to mouth may have been unaffected.

Analgesia 2002; 94: 706–10.

It is more likely, however, that the

epidural catheter had been placed in, or

migrated to, the subdural space. As this is

a potential space, small amounts of local

anaesthetic can produce very rapid sen-

sory blockade [3]. This classically occurs

with minimal motor block and cardio-

vascular disturbance, which is in com-

plete contrast to an extended spinal or

epidural block. Recognition is the most

important element of treatment, it is not

always necessary to remove the catheter,

although the infusion doses need to be

adjusted appropriately.

Mulroy MF. Systemic toxicity and

cardiotoxicity from local anaesthetics:

Incidence and preventive measures.

Regional Anesthesia and Pain Medicine

2

002; 27: 556–61.

Burning issue: a danger

of epidurals

A 30-year-old primagravida with a

)

2

body mass index (BMI) 54 kg.m was

admitted to hospital for induction of

labour. She was brought to the delivery

suite for artiﬁcial rupture of membranes

(ARM) and augmentation of labour. In

anticipation of difﬁculties during labour

associated with morbid obesity, an epi-

dural was sited immediately after the

ARM. The epidural was sited using a

standard 16G Tuohy needle at the L3 ⁄ 4

interspace under aseptic conditions using

a loss of resistance to saline technique.

The procedure was uneventful and the

catheter was passed at the ﬁrst attempt. A

test dose of 3 ml lidocaine 2% was given

with no effect. She was given a ﬁrst top-

up of 10 ml plain bupivacaine 0.25%.

The level of the block was checked after

15 min with ethyl chloride and loss of

sensation to cold was detected up to the

T10 dermatome bilaterally. With the ﬁrst

dose and every subsequent top-up (15 ml

plain bupivacaine 0.1% with fentanyl

We would like to highlight a recent

problem encountered while using epi-

dural anaesthesia. A triple arthrodesis of

the hind foot was performed on a

This case illustrates that a simple error

in evaluating the level of sensory block-

ade can lead to serious thermal injuries

from something as innocuous as a cup

of coffee. It is important to be aware of

the possibility of a spinal or epidural

block becoming subdural. Monitoring,

including pain intensity and severity,

level of motor and sensory blockade on

chest wall and upper limb, and cardio-

respiratory observations must be done

to ensure appropriate patient care.

6

0-year-old man with ankylosing

spondylitis, using combined spinal-

epidural anaesthesia. Due to underlying

disease, placement of the epidural cath-

eter was technically difﬁcult though

ultimately successful. Surgery was

uneventful. With an epidural infusion

(

bupivacaine 0.4%), the patient was

comfortable during the ﬁrst postopera-

tive night, although the following

morning he complained of severe foot

pain and was given two boluses (8 ml

each of bupivacaine 0.4%) as prescribed

by an infusion protocol. Fifteen minutes

later he complained of tingling in his

mouth and difﬁculty coughing. Hoarse-

ness was noted and the epidural infusion

was discontinued. The patient initially

was unable to feel ice at the base of his

J. M. Murnaghan

S. A. Henderson

R. W. Allen

Musgrave Park Hospital,

Belfast BT9 7JB, UK

E-mail: mark@murnaghan.fsnet.co.uk

)

1

References

2 lg.ml ) she complained of bilateral

hearing loss, which disappeared sponta-

neck (C3 dermatome), although motor 1 Bridenbaugh LD. Neural blockade in

function was unaltered in the upper

limbs. His ice levels had fallen to the

nipple line (T3 dermatome) when he

asked for a cup of coffee. Ten minutes

later, he noticed a strange feeling in his

clinical anaesthesia and management of neously after 30–60 s. After 10 h on

pain. In: Cousins MJ, Bridenbaugh PO, delivery suite, the patient underwent

eds. Complications of Local Anaesthetic

Neural Blockade, 2nd edn. Lippincott,

702–15.

lower segment Caesarean section for

failure to progress in labour. Anaesthesia

was achieved with 20 ml plain bupiva-

)

1

ﬁngers, which subsequently became 2 Grieff J, Cousins MJ. Subarachnoid and caine 0.5% with fentanyl 5 lg.ml

very painful and blistered. He had

epidural anaesthesia. In: Nimmo WS,

given as two 10-ml boluses. Transient

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.

deafness occurred with each top-up

similar to that described previously.

V. K. Gund

M. J. Clark

The immediate postoperative period

was unremarkable. She was followed up

regularly for 3 days and was discharged

home on the fourth postoperative day.

We have not been able to ﬁnd similar

cases described in the literature. Low

frequency hearing loss associated with

spinal anaesthesia has been described in

the literature [5], presumed to be as a

result of cerebrospinal ﬂuid (CSF) leak.

There was no suspicion of dural punc-

ture in this case. It is possible that

pressure changes in the CSF associated

with injection of an epidural bolus

could have contributed to the hearing

loss. We would be interested to hear

from other parties as to their opinion of

the cause of this patient’s symptoms.

W. F. Sellers

Pontefract General Inﬁrmary,

Pontefract WF8 1 PL, UK

E-mail: wfssellers@hotmail.com

Gum elastic bougies

I read with interest the background to

the introduction of the gum elastic

bougie as an aid to intubation. When I

started anaesthesia training in Cardiff in

1

976, gum elastic bougies (with straight

tips) were widely available, and I

learned to use them on a regular basis.

On transfer to a region in the North of

England in 1980, there were no gum

elastic bougies anywhere to be seen. I

asked if they could be obtained but this

seemed to be resisted. I therefore ruth-

lessly applied the following strategy.

Every time I anticipated the need for a

Figure 6

Table 2

A. K. Rajasekaran

P. Kirk

S. Varshney

North Manchester General Hospital,

Manchester M8 5RB, UK

Oxygen

ﬂow;

Oxygen tubing Suction tubing gum elastic bougie, or even when I

pressure;

needed one unexpectedly, I asked for

the whole oesophageal dilator set, which

comprised of a range of about 30 rubber

and gum elastic bougies of varying sizes,

all with straight tips (although the larger

ones were tapered at the ends). I would

have to open the whole pack and select

the appropriate size (for a child or adult),

after which, the whole set had to be

re-sterilised. After about eight such uses,

the message got home, and dedicated

)1

l..min

mmHg

References

2

3

4

5

6

98

125

14

31

1

2

Yentis SM, Brighouse D, May A,

Bogod D, Elton C. Analgesia, Anaes-

thesia and Pregnancy – A Practical Guide.

London: WB Saunders, 2001.

132

48

250

77

338

90

1

0

5

> 350

94

Johkura K, Matsushita Y, Kuroiwa Y.

Transient hearing loss after accidental

dural puncture in epidural block.

European Journal of Neurology 2000; 7:

173

1

25–6.

recovery oxygen ﬂowmeters to oper- gum elastic intubating bougies were

ating room was considered; the tubing to duly purchased.

3

Lybecker H, Andersen T. Repetitive

hearing loss following dural puncture

treated with autologous epidural blood of both green oxygen ‘bubble’ tubing such juvenile tactics these days to obtain

follow the patient’s trolley. Thirty metres

Of course, we do not have to apply

patch. Acta Anaesthesiologica Scandinavica and electrically conductive suction tub- essential equipment!

ing (Pennine Healthcare) were studied to

measure resistance to oxygen ﬂow.

1

995; 39: 987–9.

A. S. Laurence

4

5

Lee CM, Peachman FA. Unilateral

hearing loss after spinal anaesthesia

treated with epidural blood patch.

Anesthesia and Analgesia 1996; 65: 312.

Walsted A, Salomon G, Olsen KS.

Royal Preston Hospital,

Preston PR2 9HT, UK

E-mail: Sandra.young@patr.nhs.uk

A wall mounted East Healthcare ﬂow

meter delivered oxygen through a brea-

thing circuit carbon dioxide analyser

connector to which was attached a

Low-frequency hearing loss after spinal Becton Dickinson Gabarith pressure A better method of Laryngeal

anaesthesia. Perilymphatic hypotonia?

transducer linked to a Siemens SC7000 Tube insertion

Scandinavian Audiology 1991; 20: 211–5. monitor (Fig. 6). The 30 m length of

tubing was laid out as straight as possible The Laryngeal Tube (LT) [1] is a relat-

and pressure measurements at different ively new supraglottic airway device

Oxygen delivery from a distance ﬂow rates were recorded (Table 2). At 10 introduced as an alternative to the laryn-

)

1

and 15 l.min the oxygen tubing was geal mask airway. Like the laryngeal

When no portable oxygen bottles were blown off the bottom of the ﬂowmeter. mask, it is inserted blindly, simply by

available for patient transfer in

a

Delivery of oxygen at a distance is opening the mouth and sliding the distal

four-theatre suite, the option of oxygen possible. Suction tubing should be used tip along the patient’s hard palate until

delivery via tubing from wall mounted if high ﬂow rates are required.

the central incisor teeth are at a prede-

6

14

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....................................................................................................................................................................................................................

.

termined level (indicated by a broad

black line) marked on the LT shaft. The

patient’s position during insertion maybe

neutral or in the snifﬁng position [2].

The difference in the method of

insertion used for the LT compared to

the laryngeal mask is that the index

ﬁnger is not used. The index ﬁnger

placed on the laryngeal mask cuff in a

pen holding manner helps the advan-

cing tip negotiate the soft tissue resist-

ance encountered. However, in the case

of the LT, this resistance is negotiated

solely by the advancing tip.

S. A. Khan

of the road, which is singularly ineffec-

tive in keeping oncoming cars from

crossing to the wrong side. Either their

equipment should be returned to the

manufacturer, on the grounds that it is

not ﬁt for purpose, or procedures in

their scanner altered so that the offend-

ing piece of equipment never goes into

the magnet room. Their hospital’s clin-

ical indemnity manager might also want

a say in this, as well as the Medical

Devices Agency.

R. M. Khan

M. M. H. Siddiqui

JN Medical College Hospital,

Aligarh, India

E-mail: drshariqalikhan@hotmail.com

References

1

2

Dorges V, Ocker H, Wenzel V,

Schmucker P. The Laryngeal tube:

A new simple airway device.

Anesthesia and Analgesia 2000; 90:

1

220–2.

A. S. Laurence

Anonymous. Instruction for use. Laryngeal

tube (LT). Sulz, Germany: VBM

Medizintechnik Gmbh, 2000.

Consultant Anaesthetist,

Royal Preston Hospital,

Preston PR2 9HT, UK

E-mail: Sandra.young@patr.nhs.uk

We have been using the LT for

elective surgery for the last 8 months

and have consistently recorded poorer

insertion rates for the LT as compared

to the laryngeal mask. We believe that Magnetic resonance compatible

these poor results can be attributed to equipment: apply common

the difference in the method of inser- sense

Estimating oxygen uptake

tion of these two devices.

Your correspondents (Leonard et al.

Anaesthesia 2002; 57: 654–8) have eval-

uated elaborate techniques for the esti-

mation of oxygen uptake, but it seems

rather perverse to use the reverse Fick

method, measuring cardiac output

invasively, to do so. All they need is an

anaesthetic machine, such as the Oh-

meda CD, which has a ‘bellows in bottle’

ventilator. This can then be used to ﬁnd

the ﬂow of oxygen required to keep the

volume constant in a completely closed

circle. Provided the carbon dioxide

absorber is working satisfactorily, and

nitrous oxide is either avoided or has

been used for 30 min or more, it follows

that the volume of oxygen added to the

circuit is equal to that used by the patient.

Or doesn’t it?

To test our hypothesis we conducted a I read with interest the incident and

study in which 13 ASA I and II patients subsequent measures taken by your

undergoing elective orthopaedic surgery correspondents (Farling et al. Anaesthesia

and who had two failed attempts at LT 2003; 58: 86–7) of painting a red line on

insertion using the method of insertion the ﬂoor when a piece of apparently

advocated by the manufacturer [2] were ‘magnet-safe’ monitoring equipment

chosen. We then recorded the success was drawn into their magnetic reson-

rate of LT insertion aided by anterior ance (MR) scanner. The offending

mandibular displacement (jaw thrust) in device weighed 25 kg and as such is

these patients.

rather heavy to be carried around on

We found that, aided with the jaw health and safety grounds. Presumably,

thrust, the LT could be inserted in six therefore, it was on a stand with castors.

out of 13 patients on the ﬁrst attempt Most MR monitors of recent manufac-

and in another two patients on the ture involve a magnet-safe front end,

second attempt; in the rest (ﬁve often on a mobile stand with castors, to

patients), the LT could not be inserted which all the patient monitoring leads

even with jaw thrust.

and cables are attached, and a separate

It is also interesting to note that telemetry receiver display unit, which

quite unintentionally) in all 13 patients can be moved round but is intended to

(

D. M. Jackson

selected for this study, ventilation using be used in the control room and is not

the face mask was difﬁcult and was only necessarily magnet-safe. To reduce the

possible when aided by a Guedel air- need to take the display unit into the

way. Moreover, nine out of 13 patients magnet room, the front end usually has

Swindon SN6 6PB, UK

E-mail: Dmjackson@doctor.org.uk

complained of snoring while asleep.

a small display unit incorporated into it.

The application of anterior mandib-

Had a patient been in the bore of the Updating Wee’s oesophageal

ular displacement helps the advancing magnet when this incident occurred, it detector

LT tip negotiate the soft tissue resist- sounds as if serious injury could have

ance, mainly by tensing the genioglossus occurred. I would not be prepared to Wee’s oesophageal detector, which

muscle, which in turn lifts the tongue work in a scanner where the equipment aspirates gas from a tracheal tube but

off the posterior pharyngeal wall. We or the ways in which it is used could not a misplaced oesophageal tube, used a

have now started inserting the LT with result in such an accident, possibly black rubber corrugated catheter mount,

the aid of anterior mandibular displace- injuring me as well as the patient. which is no longer available [1]. While

ment and have found a signiﬁcant Relying on a painted red line on the trying to ﬁt a 50-ml bladder syringe to a

improvement in the rate of successful ﬂoor indicating the safe area is as useless clear plastic 15 mm ⁄ 22 mm angle piece,

insertions.

as a painted white line down the middle the operating department practitioner

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.

Figure 7

(

S.P.H.) pointed out that the Mapleson 2 Chan YK, Zuraidah S, Tan PSK. Use

C disposable breathing system (DAR ⁄

Mallinckrodt (286 ⁄ 7814) contained a

green and clear soft plastic adaptor for

of capnography delaying the diagnosis

of tracheal intubation. Anaesthesia 1998;

53: 1207–8.

Figure 8

wall mounted oxygen delivery cone to 3 Hirsch NP. Confirmation of tracheal

tube placement. Anaesthesia 1988;

43: 72.

1

5 mm female connection, and the clear

Inspired advice for the

FRCA vivas

adaptor ﬁts the bladder syringe nozzle

beautifully (Fig. 7).

Wee suggested using his device when Measuring non-invasive blood

a capnograph was not available, for pressure in obese patients

example in an Accident and Emergency

The vivas for the most recent sitting of

the Primary FRCA were held in rooms

at the Bloomsbury Central Baptist

Church. Outside the church was this

sign (Fig. 8), presumably intended for

potential worshippers but which also

seemed to be ﬁne advice for the exam.

I am sure that many candidates over

the years have looked for divine inspira-

tion but can we now assume that this has

become a College recommendation?

Department. The capnograph will not Measuring blood pressure (BP) non-

show a carbon dioxide trace in a patient invasively in obese patients can be

with severe bronchospasm [2] or pro- difﬁcult when using a cuff at the upper

found hypotension, both of which can arm, especially when it is conical in

occur in anaphylaxis. ‘Hold up’ of an shape. Recently, I was able to overcome

Eschmann gum elastic bougie when this problem by using a child’s cuff at the

passed through a tracheal tube will wrist of an obese patient. However, it

conﬁrm tracheal placement and is may not be suitable for very frequent

recommended in these cases at the measurements and for long cases because

University of Washington Hospitals, of several nerves that can get compressed

Seattle (personal communication, Fred at the wrist. By using a child’s cuff at the

W. Cheney). Listening to the chest after wrist, the need for invasive BP due to

every tracheal intubation will give an difﬁculty in measuring may be avoided

aural memory, which should alert when for short cases. The basic principles of

things don’t sound right. If you haven’t non-invasive blood pressure and the

seen the tube pass through the vocal relationship between the cuff width

cords, then these are all ‘useful tools in and the circumference of the limb are

the ﬁght against inadvertent oesopha- clearly explained in the reference given

H. Wellesley

Bristol Royal Inﬁrmary,

Bristol BS2 8HW, UK

E-mail: hugowellesley@yahoo.com

geal intubation’ [3].

below [1].

W. F. S. Sellers

G. U. Weeratunga

S. P. Holesworth

Hutt Hospital,

Pontefract General Inﬁrmary,

Pontefract WF8 1PL, UK

E-mail: wfssellers@hotmail.com

Lower Hutt, New Zealand

E-mail: georgeupali@xtra.co.nz

Reference

References

Wee MYK. The Oesophageal

1 Hutton P, Cooper GM, James FM,

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ciples and Practice of Anaesthesia. Dunitz

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DOI: 10.1046/j.1365-2044.2003.03207_25.x

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