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BRAIN DAMAGE AFTER DENTAL ANÆSTHESIA
1248
Letters
to
the Editor
teaching them to care for the patients in the ward situation. Their presence there is welcomed by the ward sister in the same way as the ward sister is welcomed in the teaching department, where her specialist knowledge contributes greatly to the free discussion which forms part of the nurses’ education. Another feature of present-day nurse education is the frequent meeting of the nursing administrative staff, ward sisters, tutors, and some enlightened consultants, to discuss how best to carry out nursing procedures, and to evolve methods acceptable to all wards and departments of the hospital. In this way the student nurse is prepared to give efficient service to the patient. Again, an important new member of the school of nursing is the clinical instructor. Dr. Dewar should also know about her function in the hospital. With regard to the nurse tutor’s training, I should like to point out that its aim is to provide her with a good theoretical background and to prepare her to implement modern teaching methods, thus enabling her to correlate theory and practice in the best possible manner. From reading the medical press the nursing profession appears to be ahead of the medical profession in preparing its members for teaching. So far it seems that no training is given to doctors in teaching methods. nurses
PANIC IN THE OPERATING-THEATRE to time in the past 10 years I have had a frantic call from a surgeon or theatre sister: " We have just operated on a case of gas-gangrene. How soon will it be safe to open the theatre again ?" In each case I have answered that the theatre can be reopened as soon as an ordinary cleaning has been done. I have always been puzzled as to wherein lay the " emergency ", and I have sought the views of my bacteriological colleagues who, it seems, have had similar experiences. Are surgeons as a whole unaware that Clostridium welchii (perfringens) is a normal inhabitant. of the large bowel, to the extent of about one million organisms (including spores) per gramme of fxces ? It seems so, because no distress signals are raised after colostomies, cscostomies, and gut resections, which take place every week. My plea is that the time for panic is not when a case of gasgangrene is brought into the theatre but rather when gas" clean " case gangrene, or worse still tetanus, develops in a If I am would care to tell me wrong, surgeons postoperatively. where and why ?
SIR,-From time
Public Health Laboratory,
Clytha Square, Newport, Monmouthshire.
M. T. ROTTER. R. D. GRAY.
SENIOR NURSING-STAFF STRUCTURE SIR,-Ifeel I cannot let Dr. Dewar’s comments (Nov. 12, p. 1074) on the status of the ward sister go unanswered. He draws attention to her " lowly " status and infers that some radical change will take place, should the Salmon recommendations be implemented. This is not so. The ward sister is a team leader, coordinating the work of the trained nursing staff, teaching the student and pupil nurse, and supervising the work of the ward clerk and other ancillary staff. She is an experienced nurse with administrative responsibilities, undertaking a very satisfying and rewarding job. None of this will change; but with a constant increase in bed-occupancy figures, and decrease in the length of patient-stay and turnover interval, her task is becoming extremely arduous. Reduction in hours for nursing staff and employment of part-time staff aggravate this, and respite from some of her more irksome duties will be welcome. The grade-7 nurse will provide the help that the ward sister needs-she will work in a liaison capacity with heads of departments, coordinating their work with ward requirements. New ideas and suggestions can frequently be introduced to a group of wards with less difficulty than to a single unit. Complications with supplies can more easily be noted, and rectified, when a larger unit is under surveillance. Consultant medical staff can be difficult, with outrageous individual idiosyncrasies, and junior medical staff are frequently ill prepared for their particular posts-the ward sister must be able to deal with all of this. She needs administrative help and support, and this is what the Salmon report recommends she should have. M. W. LARRETT.
BRAIN DAMAGE AFTER DENTAL ANÆSTHESIA SIR,-In their article (Oct. 22, p. 869) Dr. Brierley and Dr. Miller say erroneously that one of the essential features of dental anxsthesia is absence of intubation. In 1962 I described the routine use of intratracheal anaathesia for 700 cases of multiple or difficult extraction (and a few cases of dental conservation) in the normal conditions of the dental surgery.’ This paper brought to light other similar experience of over 14,000 such cases in the hands of other workers,2 a total which, though small in itself, must be seen against the background of the key position which tracheal intubation holds in modern anaesthesia and the experience of millions of cases in hospital. In my opinion patients requiring dental anxsthetics fall into three categories: (1) those in whom intubation is clearly unnecessary; (2) those in whom intubation is clearly essential; and (3) a borderline group, about whom doubt exists. I think that most of the last category should be intubated, prevention of anxsthetic difficulties being much easier than their cure. The advantages of intubation are relevant to the case reported by Dr. Brierley and Dr. Miller, and to many others, and are as follows: 1. Complete control of the airway with certain prevention of obstruction and of aspiration of blood, teeth, and septic tartar. 2. Reduction of haemorrhage and of laceration of soft tissues because of better access to the operating-field and the elimination of the need for haste, and of haste itself, from the operating-
technique. 3. Reliability, so ensuring that the dentist can be reasonably certain of completing what he sets out to do without putting the patient’s life or health into serious hazard-a feature of no other current general dental anaesthetic technique. 4. The freedom given to the anaesthetist to monitor his patient’s condition and
on
SIR,-Dr. Dewar’s letter suggests that he may be ill informed nursing matters in general and, in particular, on the work
in 1966. The points he makes about wardsister/nurse-tutor relations and tutors’ training are years behind the times. The nursing profession has worked towards a change in nurse education over a long period. The General Nursing Council for England and Wales experimental syllabus for general nurse training, published in 1962, has proved a notable milestone in this endeavour, and has been implemented in many hospitals while the Salmon and Platt reports are still being discussed. In this scheme of training the tutors spend some time each day in the wards working with the student of
nurse tutors
to
institute any necessary
treatment-a
freedom
notably lacking in non-intubational techniques. 5. The ability to maintain a light plane of anxsthesia without fear of the patient becoming unmanageable from the movements which may occur in too light anaesthesia, for it is as easy to deepen a too-light anaesthetic in an intubated patient, at will and in safety, as it is difficult or dangerous in the unintubated, in whom the anaesthetist must try to maintain the right level of anaesthesia without full control of the airway, knowing that the dentist may fail to avoid mouth breathing on the one hand or airway obstruction or the aspiration of blood on the other. In the unintubated patient the dennst’ss responsibility for the placing of the mouth pack and its imperfect efficiency make it impossible for the anaesthetist to guarantee proper and full control of the anaesthetic. 1. 2.
Danziger, Danziger,
A. M. Br. A. M. ibid.
dent. J. 1962. 113, 426. 1964, 117, 267.
1249 6. The ability to control (or judge) respiration by the use of the rebreathing bag necessitated by this technique-an ability which is not offered in the same measure by any other dental anxsthetic
reported by Mitskevitch.e Unlike the studies of Ritter and
technique. 7. The ability
Lawrence, histolog-
in the
supine position if at any time this should become necessary (though it has seldom proved necessary in my experience of 2000 cases) without the risk and fear of aspiration of blood and airway obstruction which in the unintubated case must deter the anaesthetist from taking this step. 8. Reduction of respiratory dead space. 9. The ability to maintain the blood-pressure (B.P.). This is a consequence of most of the preceding advantages of intubation. In addition the nicotine-like effect of succinylcholine and the stimuli arising from laryngoscopy and from intubation in light anesthesia tend to raise B.P.34 Although the B.P. may tend to fall again if allowed to in the course of a long-continued anxsthetic, the early detection and treatment of such a trend is a simple matter in the intubated patient, though difficult or impossible in the unintubated. Dr.
! ’
’
to
place
the
patient
and Dr. Miller rightly stress that, though fainting may occasionally coincide with the induction of anaathesia, acute hypotension at any other stage is due to other causes. These causes are in my view preventable or well known, and it is a great disservice to progress in dental anesthesia to blanket them all under the designation " fainting under anxsthesia ", which has become an excuse offered for the consequences of all sorts of anaesthetic indiscretions. Contrary to current Ministry thinking, it is not necessary for the patient to have a history of medical disease for intratracheal anxsthesia to be indicated. Less than 5% of the patients I find it essential or advisable to intubate have any medical history, and in most of the 5% who have there are other anaesthetic indications for intubation. The two most important safety factors in modern anxsthesia are the development of tracheal intubation and the deliberate creation, out of necessity, of a body of trained anaesthetists. The patient needs both these safety factors in the dental surgery as much as in the operating-theatre. Neither is adequate alone. No dentist or doctor requiring multiple dental extractions would allow himself to be subjected to non-intubational anxsthesia, nor would he be expected to. Both professions, unlike the public, are aware of the hazards of such techniques and the safer alternatives now available. It cannot be right for us to continue to do to others what we would not have others do to us. In Britain today, most patients requiring multiple dental extractions are anaesthetised by dentists and doctors for the most part undertrained in modern anaesthesia, by methods which I consider to be technically backward and morally insupportable. The historic reasons for this are no longer valid.
Brierley
ARNOLD M. DANZIGER.
ical examination of the middle and inner ears from our P.T.U.treated chick embryos revealed consistent alterations confined to the sensory hair cells of the cochlea in the area of the maculae
lagenas (figure a) and in the spiral ganglion of the cochlea. No abwere normalities observed in the
auditory nerve, brain-stem, or middle
ear.
of the cochlea from a Sensory hair cells from the cochlea of a newly-hatched chick: (a) inoculated with control chick are P.T.U., on 10th incubation day; (b) control. shown in figure b. Reduced to (Haematoxylin and eosin. We have obtained about half from x 1470.) preliminary results indicating that if 50-75 fLg. of L-thyroxine is given either simultaneously with (or as long as about 120 hours after) the P.T.u. injection on the 10th incubation day, one cannot detect the thyroid lesions or the abnormal histological findings in the sensory hair cells of the cochlea and its ganglion.
Sensory cells
This study was supported by grants Tl-AM-5277 and AM-02504, National Institute of Arthritis and Metabolic Diseases, National Institutes of Health, U.S. Public Health Service. Genetic and Endocrine Unit, Department of Pediatrics, State University of New York, GERALD J. BARGMAN Upstate Medical Center, LYTT I. GARDNER. Syracuse, New York 13210, U.S.A.
PROGRAMMED LEARNING
SIR,-Those engaged in teaching medical sciences may be interested in the application of programmed learning to medical education, and in a new source of information on the subject-the National Centre for Programmed Learning which has recently surveyed the subject and will answer individual inquiries. Programmes " are self-instructional, and have been produced in a way which has been empirically proved to teach effectively. In addition, authors are expected to try them out with students and to revise them as necessary before publica"
OTIC LESIONS AND CONGENITAL HYPOTHYROIDISM an effort to elucidate the relation, if any, between SIR,-In thyroid abnormality and congenital deafness in Pendred’s syndrome5 an experiment was designed to study the effects of hypothyroidism on middle-ear and inner-ear hearing structures (including the auditory nerve and its central projection) in
developing chick embryos. Following the techniques of Romanoff,chick embryos were made hypothyroid with propylthiouracil (P.T.U.). After hatching, the thyroid glands, middle and inner ear mechanisms, and the auditory nerve and brain-stem of the survivors were examined grossly and microscopically by hxmatoxylin and eosin staining, or by silver impregnation using the technique of Cajal and DeCastro as described by Levi-Montalcini.7 The thyroidgland findings in the P.T.u.-treated chicks were similar to those 3. 4. 5. 6. 7.
Graf, K., Strom, G., Wahlin, A. Acta anoesth. scand. 1963, suppl. Graf, K., Wahlin, A. ibid. 1963, 7, 169. Pendred, V. Lancet, 1896, ii, 532. Romanoff, A. L., Laufer, H. Endocrinology, 1956, 59, 611. Levi-Montalcini, R. J. comp. Neurol. 1949, 91, 209.
tion.
Programmes
are
generally published
as
textbooks, although
have been produced as film-strips for a teaching machine, and one series is used in conjunction with a cine-film. As a rule, a programme does not attempt to cover a large field of knowledge, but provides carefully structured explanation of or practice in an aspect of medicine which students find difficult. Thus there are programmes dealing with the biochemistry of body fluids, and with neurophysiology and neuroanatomy, and others which attempt to teach diagnostic skills. Although the range of published programmes is still small, and their quality variable, those available could serve as useful supplements for medical students, and perhaps save some some
8.
14.
9.
Mitskevitch, J. S. Glands of Internal Secretion in the Embryonic Development of Birds and Mammals. Moscow, 1957. Published for the National Science Foundation and the Department of Health, Education and Welfare, U.S.A., by the Israel Program for Scientific Translations, 1959. Ritter, F. N., Lawrence, M. Trans. Am. lar. rhinol. otol. Soc., Inc. 1960 p. 270.
Letters
to
the Editor
teaching them to care for the patients in the ward situation. Their presence there is welcomed by the ward sister in the same way as the ward sister is welcomed in the teaching department, where her specialist knowledge contributes greatly to the free discussion which forms part of the nurses’ education. Another feature of present-day nurse education is the frequent meeting of the nursing administrative staff, ward sisters, tutors, and some enlightened consultants, to discuss how best to carry out nursing procedures, and to evolve methods acceptable to all wards and departments of the hospital. In this way the student nurse is prepared to give efficient service to the patient. Again, an important new member of the school of nursing is the clinical instructor. Dr. Dewar should also know about her function in the hospital. With regard to the nurse tutor’s training, I should like to point out that its aim is to provide her with a good theoretical background and to prepare her to implement modern teaching methods, thus enabling her to correlate theory and practice in the best possible manner. From reading the medical press the nursing profession appears to be ahead of the medical profession in preparing its members for teaching. So far it seems that no training is given to doctors in teaching methods. nurses
PANIC IN THE OPERATING-THEATRE to time in the past 10 years I have had a frantic call from a surgeon or theatre sister: " We have just operated on a case of gas-gangrene. How soon will it be safe to open the theatre again ?" In each case I have answered that the theatre can be reopened as soon as an ordinary cleaning has been done. I have always been puzzled as to wherein lay the " emergency ", and I have sought the views of my bacteriological colleagues who, it seems, have had similar experiences. Are surgeons as a whole unaware that Clostridium welchii (perfringens) is a normal inhabitant. of the large bowel, to the extent of about one million organisms (including spores) per gramme of fxces ? It seems so, because no distress signals are raised after colostomies, cscostomies, and gut resections, which take place every week. My plea is that the time for panic is not when a case of gasgangrene is brought into the theatre but rather when gas" clean " case gangrene, or worse still tetanus, develops in a If I am would care to tell me wrong, surgeons postoperatively. where and why ?
SIR,-From time
Public Health Laboratory,
Clytha Square, Newport, Monmouthshire.
M. T. ROTTER. R. D. GRAY.
SENIOR NURSING-STAFF STRUCTURE SIR,-Ifeel I cannot let Dr. Dewar’s comments (Nov. 12, p. 1074) on the status of the ward sister go unanswered. He draws attention to her " lowly " status and infers that some radical change will take place, should the Salmon recommendations be implemented. This is not so. The ward sister is a team leader, coordinating the work of the trained nursing staff, teaching the student and pupil nurse, and supervising the work of the ward clerk and other ancillary staff. She is an experienced nurse with administrative responsibilities, undertaking a very satisfying and rewarding job. None of this will change; but with a constant increase in bed-occupancy figures, and decrease in the length of patient-stay and turnover interval, her task is becoming extremely arduous. Reduction in hours for nursing staff and employment of part-time staff aggravate this, and respite from some of her more irksome duties will be welcome. The grade-7 nurse will provide the help that the ward sister needs-she will work in a liaison capacity with heads of departments, coordinating their work with ward requirements. New ideas and suggestions can frequently be introduced to a group of wards with less difficulty than to a single unit. Complications with supplies can more easily be noted, and rectified, when a larger unit is under surveillance. Consultant medical staff can be difficult, with outrageous individual idiosyncrasies, and junior medical staff are frequently ill prepared for their particular posts-the ward sister must be able to deal with all of this. She needs administrative help and support, and this is what the Salmon report recommends she should have. M. W. LARRETT.
BRAIN DAMAGE AFTER DENTAL ANÆSTHESIA SIR,-In their article (Oct. 22, p. 869) Dr. Brierley and Dr. Miller say erroneously that one of the essential features of dental anxsthesia is absence of intubation. In 1962 I described the routine use of intratracheal anaathesia for 700 cases of multiple or difficult extraction (and a few cases of dental conservation) in the normal conditions of the dental surgery.’ This paper brought to light other similar experience of over 14,000 such cases in the hands of other workers,2 a total which, though small in itself, must be seen against the background of the key position which tracheal intubation holds in modern anaesthesia and the experience of millions of cases in hospital. In my opinion patients requiring dental anxsthetics fall into three categories: (1) those in whom intubation is clearly unnecessary; (2) those in whom intubation is clearly essential; and (3) a borderline group, about whom doubt exists. I think that most of the last category should be intubated, prevention of anxsthetic difficulties being much easier than their cure. The advantages of intubation are relevant to the case reported by Dr. Brierley and Dr. Miller, and to many others, and are as follows: 1. Complete control of the airway with certain prevention of obstruction and of aspiration of blood, teeth, and septic tartar. 2. Reduction of haemorrhage and of laceration of soft tissues because of better access to the operating-field and the elimination of the need for haste, and of haste itself, from the operating-
technique. 3. Reliability, so ensuring that the dentist can be reasonably certain of completing what he sets out to do without putting the patient’s life or health into serious hazard-a feature of no other current general dental anaesthetic technique. 4. The freedom given to the anaesthetist to monitor his patient’s condition and
on
SIR,-Dr. Dewar’s letter suggests that he may be ill informed nursing matters in general and, in particular, on the work
in 1966. The points he makes about wardsister/nurse-tutor relations and tutors’ training are years behind the times. The nursing profession has worked towards a change in nurse education over a long period. The General Nursing Council for England and Wales experimental syllabus for general nurse training, published in 1962, has proved a notable milestone in this endeavour, and has been implemented in many hospitals while the Salmon and Platt reports are still being discussed. In this scheme of training the tutors spend some time each day in the wards working with the student of
nurse tutors
to
institute any necessary
treatment-a
freedom
notably lacking in non-intubational techniques. 5. The ability to maintain a light plane of anxsthesia without fear of the patient becoming unmanageable from the movements which may occur in too light anaesthesia, for it is as easy to deepen a too-light anaesthetic in an intubated patient, at will and in safety, as it is difficult or dangerous in the unintubated, in whom the anaesthetist must try to maintain the right level of anaesthesia without full control of the airway, knowing that the dentist may fail to avoid mouth breathing on the one hand or airway obstruction or the aspiration of blood on the other. In the unintubated patient the dennst’ss responsibility for the placing of the mouth pack and its imperfect efficiency make it impossible for the anaesthetist to guarantee proper and full control of the anaesthetic. 1. 2.
Danziger, Danziger,
A. M. Br. A. M. ibid.
dent. J. 1962. 113, 426. 1964, 117, 267.
1249 6. The ability to control (or judge) respiration by the use of the rebreathing bag necessitated by this technique-an ability which is not offered in the same measure by any other dental anxsthetic
reported by Mitskevitch.e Unlike the studies of Ritter and
technique. 7. The ability
Lawrence, histolog-
in the
supine position if at any time this should become necessary (though it has seldom proved necessary in my experience of 2000 cases) without the risk and fear of aspiration of blood and airway obstruction which in the unintubated case must deter the anaesthetist from taking this step. 8. Reduction of respiratory dead space. 9. The ability to maintain the blood-pressure (B.P.). This is a consequence of most of the preceding advantages of intubation. In addition the nicotine-like effect of succinylcholine and the stimuli arising from laryngoscopy and from intubation in light anesthesia tend to raise B.P.34 Although the B.P. may tend to fall again if allowed to in the course of a long-continued anxsthetic, the early detection and treatment of such a trend is a simple matter in the intubated patient, though difficult or impossible in the unintubated. Dr.
! ’
’
to
place
the
patient
and Dr. Miller rightly stress that, though fainting may occasionally coincide with the induction of anaathesia, acute hypotension at any other stage is due to other causes. These causes are in my view preventable or well known, and it is a great disservice to progress in dental anesthesia to blanket them all under the designation " fainting under anxsthesia ", which has become an excuse offered for the consequences of all sorts of anaesthetic indiscretions. Contrary to current Ministry thinking, it is not necessary for the patient to have a history of medical disease for intratracheal anxsthesia to be indicated. Less than 5% of the patients I find it essential or advisable to intubate have any medical history, and in most of the 5% who have there are other anaesthetic indications for intubation. The two most important safety factors in modern anxsthesia are the development of tracheal intubation and the deliberate creation, out of necessity, of a body of trained anaesthetists. The patient needs both these safety factors in the dental surgery as much as in the operating-theatre. Neither is adequate alone. No dentist or doctor requiring multiple dental extractions would allow himself to be subjected to non-intubational anxsthesia, nor would he be expected to. Both professions, unlike the public, are aware of the hazards of such techniques and the safer alternatives now available. It cannot be right for us to continue to do to others what we would not have others do to us. In Britain today, most patients requiring multiple dental extractions are anaesthetised by dentists and doctors for the most part undertrained in modern anaesthesia, by methods which I consider to be technically backward and morally insupportable. The historic reasons for this are no longer valid.
Brierley
ARNOLD M. DANZIGER.
ical examination of the middle and inner ears from our P.T.U.treated chick embryos revealed consistent alterations confined to the sensory hair cells of the cochlea in the area of the maculae
lagenas (figure a) and in the spiral ganglion of the cochlea. No abwere normalities observed in the
auditory nerve, brain-stem, or middle
ear.
of the cochlea from a Sensory hair cells from the cochlea of a newly-hatched chick: (a) inoculated with control chick are P.T.U., on 10th incubation day; (b) control. shown in figure b. Reduced to (Haematoxylin and eosin. We have obtained about half from x 1470.) preliminary results indicating that if 50-75 fLg. of L-thyroxine is given either simultaneously with (or as long as about 120 hours after) the P.T.u. injection on the 10th incubation day, one cannot detect the thyroid lesions or the abnormal histological findings in the sensory hair cells of the cochlea and its ganglion.
Sensory cells
This study was supported by grants Tl-AM-5277 and AM-02504, National Institute of Arthritis and Metabolic Diseases, National Institutes of Health, U.S. Public Health Service. Genetic and Endocrine Unit, Department of Pediatrics, State University of New York, GERALD J. BARGMAN Upstate Medical Center, LYTT I. GARDNER. Syracuse, New York 13210, U.S.A.
PROGRAMMED LEARNING
SIR,-Those engaged in teaching medical sciences may be interested in the application of programmed learning to medical education, and in a new source of information on the subject-the National Centre for Programmed Learning which has recently surveyed the subject and will answer individual inquiries. Programmes " are self-instructional, and have been produced in a way which has been empirically proved to teach effectively. In addition, authors are expected to try them out with students and to revise them as necessary before publica"
OTIC LESIONS AND CONGENITAL HYPOTHYROIDISM an effort to elucidate the relation, if any, between SIR,-In thyroid abnormality and congenital deafness in Pendred’s syndrome5 an experiment was designed to study the effects of hypothyroidism on middle-ear and inner-ear hearing structures (including the auditory nerve and its central projection) in
developing chick embryos. Following the techniques of Romanoff,chick embryos were made hypothyroid with propylthiouracil (P.T.U.). After hatching, the thyroid glands, middle and inner ear mechanisms, and the auditory nerve and brain-stem of the survivors were examined grossly and microscopically by hxmatoxylin and eosin staining, or by silver impregnation using the technique of Cajal and DeCastro as described by Levi-Montalcini.7 The thyroidgland findings in the P.T.u.-treated chicks were similar to those 3. 4. 5. 6. 7.
Graf, K., Strom, G., Wahlin, A. Acta anoesth. scand. 1963, suppl. Graf, K., Wahlin, A. ibid. 1963, 7, 169. Pendred, V. Lancet, 1896, ii, 532. Romanoff, A. L., Laufer, H. Endocrinology, 1956, 59, 611. Levi-Montalcini, R. J. comp. Neurol. 1949, 91, 209.
tion.
Programmes
are
generally published
as
textbooks, although
have been produced as film-strips for a teaching machine, and one series is used in conjunction with a cine-film. As a rule, a programme does not attempt to cover a large field of knowledge, but provides carefully structured explanation of or practice in an aspect of medicine which students find difficult. Thus there are programmes dealing with the biochemistry of body fluids, and with neurophysiology and neuroanatomy, and others which attempt to teach diagnostic skills. Although the range of published programmes is still small, and their quality variable, those available could serve as useful supplements for medical students, and perhaps save some some
8.
14.
9.
Mitskevitch, J. S. Glands of Internal Secretion in the Embryonic Development of Birds and Mammals. Moscow, 1957. Published for the National Science Foundation and the Department of Health, Education and Welfare, U.S.A., by the Israel Program for Scientific Translations, 1959. Ritter, F. N., Lawrence, M. Trans. Am. lar. rhinol. otol. Soc., Inc. 1960 p. 270.