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40 tion between functional and organic fails to take into account the psychogenic factors in, for example, bronchial asthma, and also the common complaint of the neurotic that he is awakened by anxiety dreams. Nocturnal enuresis is conditioned, as Hobhouse 5 points out, by sleep. Apart from its interest for the paediatrician, its onset in adults may be the first sign of organic nervous disease such as tabes, disseminated sclerosis, and chronic meningomyelitis. The patient with cardiovascular disease has many nocturnal symptoms. The recumbent posture may embarrass his heart action and his breathing, so that he suffers from air-hunger of any severity up to the grave attack of cardiac asthma. His congested kidneys work overtime during the night, so he suffers from nycturia-which may be the first sign of incipient cardiac decompensation. Lessened irritability of the respiratory centre and increased vagal tone probably play a part in both cardiac and bronchial asthma during sleep. Another classical nocturnal symptom is pain from an attack of gout ; this is probably associated with the lowered excretion of uric acid during sleep. In conclusion, Engel remarks that, while symptoms during sleep may be of great diagnostic importance, we are still too ignorant of the pathogenesis of most of them to say why they should be creatures of nocturnal habits. 5. Hobhouse, N. Nervous Disorders in Infancy and Childhood. London, 1932; p. 148. 6. Church, V. E. Lancet, 1950, i, 281. 7. Lynas, M. A. Ibid, p. 373. 8. Wammock, V. S., Biedermaim, A. A., Jordan, R. S. J. Amer. med. Ass. 1951, 147, 637. TREATMENT OF STEVENS-JOHNSON SYNDROME THE severe form of erythema multiforme exudativum known as Stevens-Johnson syndrome is now fairly firmly established as a clinical entity. It is a febrile illness characterised by purulent conjunctivitis, ulceromem- branous stomatitis, ulceration of the genitalia and anus, and a widespread eruption of vesicles, bullse, and erythe- matous lesions on the skin, occasionally accompanied by pulmonary consolidation. Its average duration is 3-4 weeks, its mortality about 10%, and blindness from corneal ulceration and scarring is the most serious sequel. The aetiology is unknown, the most likely suggestions being a virus infection and hypersensitivity to drugs or other allergens. Secondary bacterial infection of the lesions is almost inevitable. The diagnosis may be puzzling, for it has to be made entirely on clinical grounds and the skin manifestations may closely resemble those of acute pemphigus, bullous impetigo, or the drug rashes. Treatment has consisted mainly in local and palliative measures. Sulphonamides, penicillin, or streptomycin, systemically or locally applied, neither shorten the illness nor diminish its mortality, but they reduce the risks from secondary infection, including that of corneal damage. There being no specific remedy, this has seemed a definite indication for giving such drugs. More dramatic results were reported with Aureomycin.’ Both Church s and Lynas treated one severe case with this antibiotic and noted striking improvement within 12 hours, followed by rapid recovery. Now Dr. Wam mock and two U.S. Army colleagues s have tried A.C.T.H. The patient was a young soldier, who had developed Stevens-Johnson syndrome about 15 days before the A.C.T.H. was begun. The dosage was 25 mg. of the hormone eight-hourly for two days, and then daily for three days, making a total’ of 225 mg. The symptomatic improvement after twelve hours’ treatment was striking, and all his symptoms and fever subsided within 48 hours ; by the fifth day he had completely recovered. Spontaneous recovery from the syndrome is usually a gradual process, so the rapidity of these changes strongly suggests that A.C.T.H. was responsible. If the success of both aureomycin and A.C.T.H. is con- firmed in further clinical trials some nice points will arise regarding both the aetiology of the syndrome and the mode of action of the two drugs. If aureomycin is successful, it will be hard to deny that Stevens-Johnson syndrome is an infection, probably by a virus. The role of A.C.T.H., with its many actions still incompletely understood, will be more difficult to explain. It seems to inhibit the allergic response to various antigens, so it might well be effective if all the manifestations of this syndrome are parts of a hypersensitive reaction to an infective agent. Coming down to brass tacks, how should a case be treated, in the rather dim light of present knowledge ? 7 In the cause of research the effects of A.c.T.H. should be compared with those of cortisone. But the clinician will think it more reasonable to aim further back, hoping that aureomycin will immobilise the unknown causal organism. Incidentally, aureomycin is less likely to cause unpleasant side-effects and easier to come by than A.c.T.H. Since Stevens-Johnson syndrome carries a considerable mortality, the practitioner faced with a severe case should lose no time in getting the patient to hospital, where aureomycin can be given without delay. 9. Berger, H. Arch. Psychiat. 1931, 94, 16. Gibbs, F. A., Gibbs. E. L., Lennox, W. G. Arch. intern. Med. 1937, 60, 154. Faul- coner, A., Fender, J. W., Bickford, R. G. Anesthesiology. 1949, 10, 601. 10. Courtin, R. F., Bickford, R. G., Faulconer, A. jun. Proc. Mayo Clin. 1950, 25, 197. 11. Bickford, R. G. Electroencephalog. clin. Neurophysiol. 1950. 2, 93. 12. Soltero, D. E., Faulconer, A. jun., Bickford, R. G. Anesthesiology. 1951, 12, 574. AUTOMATIC ANÆSTHESIA THE electro-encephalographic pattern during anaesthesia has been closely studied.9 9 Courtin and his associates 10 at the Mayo Clinic observed that there is a constant relation between the E.E.G. pattern and the depth of anaesthesia : and thus the levels of anaesthesia have been redefined in terms of the E.E.G. changes. As might be expected, the energy output from the brain gradually becomes less as anaesthesia deepens. From this starting-point the path of investigation has led to the development of ingenious mechanical and electronic devices, the latest of which maintains anaesthesia automatically.11 The energy output from an E.E.G. apparatus is fed into one end of this device. At the other end is an anaesthetic machine administering either thiopentone intravenously or ether by inhalation. As the energy output from the E.E.G. apparatus increases, more anaes- thetic is delivered to the patient ; the desired level of anaesthesia can thus be automatically maintained. The level can be varied by means of the " attenuation control," which alters the relation between the amount of anaesthetic drug delivered per unit output of energy from the brain. The latest report 12 from the Mayo Clinic describes how 50 patients-46 of whom had intra- abdominal operations-were anaesthetised by this auto- matic or ’ Servo ’ apparatus. The anaesthetic consisted of nitrous oxide, oxygen, and ether, and the patients were connected up to the servo aneesthetiser after they had been intubated. Anaesthesia was stabilised at a level at which the E.E.G. pattern indicated a safe surgical anaes- thetic level. Respiratory arrest occurred in one case: but in this instance the E.E.G. pattern was clearly not a reliable guide, and the level indicated was far from " safe." A device was therefore incorporated which cuts off the supply of anesthetic automatically when the respiratory rate or blood-pressure falls below a pre- determined level. These American workers hasten to counter any suggestion that such a complex electromechanical device could replace a competent anaesthetist. They suggest that the apparatus may be of value in animal research. when constant levels of anaesthesia have to be main- tained for long periods. In the clinical field, however, it is possible that when long-continued deep narcosis is
Transcript
Page 1: AUTOMATIC ANÆSTHESIA

40

tion between functional and organic fails to take intoaccount the psychogenic factors in, for example, bronchialasthma, and also the common complaint of the neuroticthat he is awakened by anxiety dreams. Nocturnalenuresis is conditioned, as Hobhouse 5 points out, bysleep. Apart from its interest for the paediatrician, itsonset in adults may be the first sign of organic nervousdisease such as tabes, disseminated sclerosis, and chronicmeningomyelitis. The patient with cardiovasculardisease has many nocturnal symptoms. The recumbent

posture may embarrass his heart action and his breathing,so that he suffers from air-hunger of any severity up tothe grave attack of cardiac asthma. His congestedkidneys work overtime during the night, so he suffersfrom nycturia-which may be the first sign of incipientcardiac decompensation. Lessened irritability of the

respiratory centre and increased vagal tone probablyplay a part in both cardiac and bronchial asthma duringsleep. Another classical nocturnal symptom is pain froman attack of gout ; this is probably associated with thelowered excretion of uric acid during sleep.

In conclusion, Engel remarks that, while symptomsduring sleep may be of great diagnostic importance, weare still too ignorant of the pathogenesis of most of themto say why they should be creatures of nocturnal habits.

5. Hobhouse, N. Nervous Disorders in Infancy and Childhood.London, 1932; p. 148.

6. Church, V. E. Lancet, 1950, i, 281.7. Lynas, M. A. Ibid, p. 373. 8. Wammock, V. S., Biedermaim, A. A., Jordan, R. S. J. Amer.

med. Ass. 1951, 147, 637.

TREATMENT OF STEVENS-JOHNSON SYNDROME

THE severe form of erythema multiforme exudativumknown as Stevens-Johnson syndrome is now fairly firmlyestablished as a clinical entity. It is a febrile illnesscharacterised by purulent conjunctivitis, ulceromem-branous stomatitis, ulceration of the genitalia and anus,and a widespread eruption of vesicles, bullse, and erythe-matous lesions on the skin, occasionally accompaniedby pulmonary consolidation. Its average duration is3-4 weeks, its mortality about 10%, and blindness fromcorneal ulceration and scarring is the most serious sequel.The aetiology is unknown, the most likely suggestionsbeing a virus infection and hypersensitivity to drugs orother allergens. Secondary bacterial infection of thelesions is almost inevitable. The diagnosis may bepuzzling, for it has to be made entirely on clinical groundsand the skin manifestations may closely resemble those ofacute pemphigus, bullous impetigo, or the drug rashes.Treatment has consisted mainly in local and palliative

measures. Sulphonamides, penicillin, or streptomycin,systemically or locally applied, neither shorten the illnessnor diminish its mortality, but they reduce the risks fromsecondary infection, including that of corneal damage.There being no specific remedy, this has seemed a definiteindication for giving such drugs. More dramatic resultswere reported with Aureomycin.’ Both Church s andLynas treated one severe case with this antibiotic andnoted striking improvement within 12 hours, followed byrapid recovery.Now Dr. Wam mock and two U.S. Army colleagues s have

tried A.C.T.H. The patient was a young soldier, who haddeveloped Stevens-Johnson syndrome about 15 daysbefore the A.C.T.H. was begun. The dosage was 25 mg.of the hormone eight-hourly for two days, and thendaily for three days, making a total’ of 225 mg. The

symptomatic improvement after twelve hours’ treatmentwas striking, and all his symptoms and fever subsidedwithin 48 hours ; by the fifth day he had completelyrecovered. Spontaneous recovery from the syndrome isusually a gradual process, so the rapidity of these changesstrongly suggests that A.C.T.H. was responsible.

If the success of both aureomycin and A.C.T.H. is con-firmed in further clinical trials some nice points willarise regarding both the aetiology of the syndrome and

the mode of action of the two drugs. If aureomycin issuccessful, it will be hard to deny that Stevens-Johnsonsyndrome is an infection, probably by a virus. The roleof A.C.T.H., with its many actions still incompletelyunderstood, will be more difficult to explain. It seemsto inhibit the allergic response to various antigens, so itmight well be effective if all the manifestations of thissyndrome are parts of a hypersensitive reaction to aninfective agent.Coming down to brass tacks, how should a case be

treated, in the rather dim light of present knowledge ? 7 In the cause of research the effects of A.c.T.H. should becompared with those of cortisone. But the clinicianwill think it more reasonable to aim further back, hopingthat aureomycin will immobilise the unknown causalorganism. Incidentally, aureomycin is less likely tocause unpleasant side-effects and easier to come by thanA.c.T.H. Since Stevens-Johnson syndrome carries a

considerable mortality, the practitioner faced with a

severe case should lose no time in getting the patient tohospital, where aureomycin can be given without delay.

9. Berger, H. Arch. Psychiat. 1931, 94, 16. Gibbs, F. A., Gibbs.E. L., Lennox, W. G. Arch. intern. Med. 1937, 60, 154. Faul-coner, A., Fender, J. W., Bickford, R. G. Anesthesiology.1949, 10, 601.

10. Courtin, R. F., Bickford, R. G., Faulconer, A. jun. Proc. MayoClin. 1950, 25, 197.

11. Bickford, R. G. Electroencephalog. clin. Neurophysiol. 1950.2, 93.

12. Soltero, D. E., Faulconer, A. jun., Bickford, R. G. Anesthesiology.1951, 12, 574.

AUTOMATIC ANÆSTHESIA

THE electro-encephalographic pattern duringanaesthesia has been closely studied.9 9 Courtin and hisassociates 10 at the Mayo Clinic observed that there is aconstant relation between the E.E.G. pattern and the

depth of anaesthesia : and thus the levels of anaesthesiahave been redefined in terms of the E.E.G. changes.As might be expected, the energy output from the braingradually becomes less as anaesthesia deepens. From this

starting-point the path of investigation has led to thedevelopment of ingenious mechanical and electronicdevices, the latest of which maintains anaesthesiaautomatically.11The energy output from an E.E.G. apparatus is fed

into one end of this device. At the other end is ananaesthetic machine administering either thiopentoneintravenously or ether by inhalation. As the energyoutput from the E.E.G. apparatus increases, more anaes-thetic is delivered to the patient ; the desired level ofanaesthesia can thus be automatically maintained. Thelevel can be varied by means of the " attenuationcontrol," which alters the relation between the amountof anaesthetic drug delivered per unit output of energyfrom the brain. The latest report 12 from the MayoClinic describes how 50 patients-46 of whom had intra-abdominal operations-were anaesthetised by this auto-matic or ’ Servo ’ apparatus. The anaesthetic consistedof nitrous oxide, oxygen, and ether, and the patients wereconnected up to the servo aneesthetiser after they hadbeen intubated. Anaesthesia was stabilised at a level atwhich the E.E.G. pattern indicated a safe surgical anaes-thetic level. Respiratory arrest occurred in one case:but in this instance the E.E.G. pattern was clearly not areliable guide, and the level indicated was far from" safe." A device was therefore incorporated whichcuts off the supply of anesthetic automatically when therespiratory rate or blood-pressure falls below a pre-determined level.These American workers hasten to counter any

suggestion that such a complex electromechanical devicecould replace a competent anaesthetist. They suggestthat the apparatus may be of value in animal research.when constant levels of anaesthesia have to be main-tained for long periods. In the clinical field, however, itis possible that when long-continued deep narcosis is

Page 2: AUTOMATIC ANÆSTHESIA

41

required therapeutically the apparatus might be useful ;but whether any advantage would accrue from dispensingwith a skilled administrator is doubtful.

1. Report on the Activities and the Meeting of the CoordinatingCommittee on Abstracting and Indexing in the Medical andBiological Sciences. UNESCO Publication 580, Paris.

COÖRDINATION OF ABSTRACTING SERVICESIx 1947 a special committee was created by UNESCO

because there seemed to be a prospect of serious duplica-tion of work by two new abstracting organisations, onein England and the other in Holland. Each of these

proposed to survey the world literature on all aspectsof medicine ; but whereas the British organisationproposed to publish abstracts of selected papers only,the Dutch intended to be comprehensive. A meetingwas called between representatives of these two bodiesand of two other senior organisations which publishabstracts related to medicine-namely, Biological Abstracts(Philadelphia) and British Abstracts (London)-andUNESCO and W.H.O. were represented. The meetingagreed that a permanent committee should be formed,to include also representatives of the American MedicalAssociation, the Association de 1’Enseignement medicaldes Hopitaux (France), the British Medical Association,the Bulletin de l’Institut Pasteur (France), the Bureauof Hygiene and Tropical Diseases (United Kingdom),Chemical Abstracts (United States), the Common-wealth Agricultural Bureaux (United Kingdom), and theMedical Library Association (United States).

This committee was set up to consider the possibilityof cooperation between these bodies. The representativesmet in Paris for four days in June, 1949, and discussedvery fully the complicated issues brought to light byconsideration of the existing and possible future activitiesof the various abstracting bodies. The results weremodest. The committee urged greater uniformity in theuse of technical terms and symbols for units of measure-ment. The attention of abstracting organisations wasdrawn to the virtues of collaboration-though perhapsnot enough attention was paid to the fact that differentclasses of reader require different abstracts of the samepaper, and that the editors of the respective abstractingjournals are best able to judge what they should publish.A resolution was taken that the committee should con-tinue its work, and an executive committee was appointed.This executive committee has held later meetings.

It is not easy to assess the value of such work. Itwas entirely sensible to explore the possibilities of

cooperation between the different organisations, and thepersonal contacts were valuable and stimulating. There

may be a place for some such body to initiate and

superintend the publication of lists of periodicals and ofmultilingual medical dictionaries.

COMMONWEALTH EXCHANGE

MANY young doctors come from other parts of theCommonwealth to work in our hospitals and to take ourexaminations. It is good to know that they are preparedto journey so far to learn at first hand something ofBritish medicine and surgery, and that our postgraduatequalifications are so highly regarded. These young menare no "new-hatch’d unfledg’d " students who come inawe and silence. They are quick to appraise all the newthings set before them, to extract their worth, and to .criticise. The more therefore should they see and hearwhat is best in this country and be given every chanceto do the work they wish in the place they wish. Itwould be selfish to exclude them from our hospitals onsome scruple that there are not enough jobs to go round.In point of fact there is no shortage of junior residentposts-rather the reverse. And when the time comes for ,promotion they may return home or stand in open Icompetition for the higher appointments.

The Commonwealth visitor has come under a varietvof arrangements, by diverse ways ; and some who camewith no very precise plan have returned home discomfited.Probably the difficulties of the expedition deter manyfrom attempting it at all. The whole affair would benefitfrom a little judicious organisation, leading we hope toa regular system of exchange between Britain and herCommonwealth partners. The traffic is mostly one-

way at present, and that is a great pity from every pointof view. When a house-physician in Brisbane comes toManchester for a year, could not a casualty-officer fromGlasgow take his place ? No doubt if the opportunity totravel were freely offered, there would be more wantingto come and go than could be accommodated, and someprocess of selection would then be needed. Morefundamental questions, however, are the number and

type of the appointments to be included in such a scheme,the hospitals which would take part, and the finance ofexchanges-for somebody must pay the fares. In

speaking recently’ about the decision that, after

qualification but before registration, every doctor shallhold a house-appointment for a year, the presidentof the General Medical Council indicated that the list of

hospitals approved for this purpose will include hospitalsin other parts of the Commonwealth.l It would be an

advantage if an exchange system were established beforethe pre-registration year becomes obligatory.We have heard it suggested that a conference of

Commonwealth representatives should be called to recom-mend exactly what should be done. Whether this wouldbe useful would depend on how well the ground wasprepared for their meeting. But certainly if, by onemeans or another, the exchange of young doctors canbe made not only frequent but positively usual,much will be gained by the profession throughout theCommonwealth.

1. Lancet, 1951, ii, 1032.

NEW YEAR HONOURS

Dr. H. P. Himsworth, who is created K.C.B., has beensecretary of the Medical Research Council since 1949,when he left the chair of medicine at University CollegeHospital. That he should receive so high an honour soearly in his new career will not surprise those who knowhis qualities of mind and heart, and will give pleasurewherever he has worked or travelled. Dr. Russell Brain,being already physician and philosopher, poet and

president, has scarcely need of further distinction ; but,if his knighthood is secondary to the esteem of his

colleagues, it is none the less becoming. Prof. R. A.Peters, F.R.S., who is also created a knight, has deservedwell of his profession because so many of his biochemicalinvestigations have had highly practical medical implica-tions-for example, those on the vitamin-B complex,on protein loss and replacement, and on dimercaprol(British anti-Lewisite) which was discovered by him andhis associates at Oxford. Dr. George Vance Allen, whois knighted for his work as vice-chancellor of the Univer-sity of Malaya, is a Belfast graduate who was bacterio-logist at Nairobi and at Kuala Lumpur before becomingprincipal of the College of Medicine at Singapore, wherehe was interned by the Japanese from 1942 to 1945.

Major-General S. R. Burston, now promoted K.B.E.,was assistant physician and physician to the RoyalAdelaide Hospital from 1914 to 1947, but is known mostwidely as director-general of medical services, AustralianMilitary Forces, during and after the late war. Amongthe many other well-deserved honours listed on p. 44,we are happy to note that Dr. Peter Kerley and Dr.Robert Machray, of Westminster Hospital, are appointedc.v.o. for their services as radiologist and anesthetistduring the recent illness of H.11. the King. while Dr.C. E. Drew, Mr. Peter Jones, and Dr. F. Scurrbecome M.v.o.


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