- Email: [email protected]
TREATMENT OF HYPOTHERMIA
1096 34 patients were treated. There regressions, and 8 patients failed
13 remissions and 13 respond. This gives an
were
to
overall response-rate of 76%. This is an encouraging figure, and it would appear from this small series that adriamycin would improve the initial response-rate. The findings merit a controlled prospective clinical trial, comparing it with the four-drug regimen from which it has been developed. This is now
underway.
Northern Ireland Radiotherapy Centre, Belfast, and Hume Street Hospital, Dublin.
G. A. EDELSTYN
Department of Medical Statistics, Queen’s University, Belfast.
K. D. MACRAE
TREATMENT OF HYPOTHERMIA
SIR,-Iwas
very interested to
see two consecutive letters’2 in situations. There is still much hypothermia exposure discussion about the bestmethod of resuscitating hypothermic victims, whether rescued from the mountainside or from water. The majority opinion seems to be that when the victim is young, and apparently fit, fairly intensive rewarming with warm water is best, in spite of possible hazards. The exact temperature of the water is still a matter of controversy, and indeed one dilemma is that it may not be possible to measure the patient’s core temperature or the bath-water temperature, since neither a low-reading nor a normal-reading thermometer are available. The risks of rewarming to the middle-aged and the old may be great enough to contraindicate the bath method. The degree of hypothermia may also be very important, because experience in hospital with older hypothermic victims suggests that those with a core temperature below 320C are in much greater danger of dying and that management in an intensive-care unit can be lifesaving. Dr Winddescribing the successful revival (at least for a time) of a child after a long period of apnoea, mentioned that the child’s deep body temperature was severely hypothermic. Several reports of successful resuscitations of this nature suggested that hypothermia was at least partly protective: presumably the small size of the victim had allowed fairly rapid cooling, producing a hibernating state. It therefore seems that, when a small child or baby has been rescued from drowning, resuscitation may be much more successful than for older and larger individuals, even when submersion has been prolonged and the water very cold. There are still the very serious risks of cardiac and other complications during rewarming and resuscitation. There is absolutely no doubt that cold injury and hypothermia play a much more serious part in drowning incidents in this country than many people acknowledge. If somebody is in danger in cold water the current view seems to be that they should stay still and only swim to land or to a boat if the swim would be very short. There is still controversy about whether the person should keep the head above water, which would put him at risk of wind exposure, or rest the head down in the water in the drown-proofing position, only raising the head to breathe. Analysis of recent drowning statistics3 and a review of hazardous hobbies4 illustrate how harmful the effects of alcohol can be, causing confusion, precipitating the person into the water, and putting him at greater risk of hypothermia.
about
Royal Life Saving Society, Desborough House, 14 Devonshire Street, London W1N 2AT.
M. F. GREEN
SIR,-At the Alpine Club’s symposium on mountain medicine and physiology there was no question of Squadron-Leader’ Davies (Oct. 4, p. 656) being "roundly castigated" for his entertaining and stimulating presentation. The main disagreement concerned the temperature of the bath, since most authorities recommend a maximum water temperature of 44-46°C with clothes. 1-7 At the symposium cases were reported of tissue damage caused by temperatures well below 50"C, The local effect of any temperature on a body tissue depends on a balance between the total heat supplied and the heat removed. The heat supplied depends on the thermal capacity of the substance, the temperature, and whether or not a change in physical state occurs. It has been observed8 that a normothermic person can only tolerate 50"C moist heat on the lips whereas the pharynx can tolerate 57"C. Provided the larynx is bypassed the trachea can tolerate dry heat up to 350oC9 whereas a review of many experimental reports" show that steam at 94-104°C is required to produce consistent damage. This variation in tolerance to heat is due to the rate at which heat is removed which in turn is governed by the variation in blood-supply to the tissues. In hypothermia the body reacts by vasoconstriction especially in the limbs and subcutaneous tissue with a decrease in the ability to remove heat and a resulting increased susceptibility to damage. Therefore it could be a dangerous assumption that, because normothermic people can tolerate a temperature of 50°C, it is necessarily safe for hypothermic victims. It is accepted that ideal treatment for immersion hypothermia is immersion in a hot bath if the bath is immediately available. 13 4 However most patients with accidental hypothermia are at a considerable distance from any bath. By the time the patient has reached hospital the body temperature has probably stabilised,2but awkward movement or bad lifting and carrying technique during the evacuation or preparation of the bath can have a profoundly depressing effect on the vital functions of the body and may result in the death of a hypothermic victim.2 Many people feel that more emphasis should be given to immediate treatment in the field (for example, camp and insulate 2) and less to evacuation to a hot bath, the value and safety of which is being questioned, especially when exhaustion is a factor." 12 Department of Anæsthetics, Royal Infirmary, Edinburgh EH3 9YW.
E. LL. LLOYD
SCREENING FOR TUBERCULOSIS IN PATIENTS WITH PNEUMOCONIOSIS
SIR,-Dr Gordon (Nov. 15,
p. 976) assumes that patients constitute a greater risk to the compneumoconiosis munity with regard to the spread of tuberculosis than do the public in general. There is no evidence to support this and indeed the contrary may be true. It is possible that the notification and attack rate of pulmonary tuberculosis is below average in this group. It can hardly, therefore, be considered to constitute 13 an important public-health risk.
with
Manchester Chest Clinic,
352 Oxford Road, Manchester M13 9NL.
F. W. A. TURNBULL
1. Adam, J. M., Goldsmith, R. in Exploration Medicine (edited by 0. G. Edholm and A. L. Bacharach); chap. 10. Bristol, 1969. 2. Freeman, J., Pugh, L. G. C. E. Int. Anæsth. Clin. 1969, 7, 997. 3. Golden, F. St. C., Rivers, J. F. Anæsthesia, 1975, 30, 364. 4. Keating, W. R. Survival in Cold Water; p. 102. Edinburgh, 1969. 5. Mountain Rescue. PAM (Air) 299, p. 177. H. M. Stationery Office, 1968 6. Mountain Rescue and Cave Rescue; p. 44. Mountain Rescue Committee, 1972. 7 Ward, M. Mountain Medicine; chap. 25. London, 1975. 8. Lloyd, E.Ll., Conliffe, N. A., Orgel, H., Walker, P. N. Scott med
J 1972,
17, 83. 1. 2. 3.
Davies, L. Lancet, Oct. 4, 1975, p. 656. Wind, J. ibid. Royal Life Saving Society, Analysis of Drowning Statistics 1973. London,
4.
Kemp,
1975. R. Practitioner,
1975, 215, 188.
9. Moritz, A. R., Henriques, F. C., McLean, R. Am J. Path. 1945, 21, 311. 10. Lloyd, E. Ll., MacRae, W. R. Br. J. Anæsth. 1971. 43, 365. 11. Moore, R. E. Mountain Medicine and Physiology; p. 13. Alpine Club, 1975. 12. Golden, F. St. C. ibid. p. 16. 13. Cochrane, A. L., Jarman, T. F., Miall, W. E. Thorax, 1956, 11, 141.
13 remissions and 13 respond. This gives an
were
to
overall response-rate of 76%. This is an encouraging figure, and it would appear from this small series that adriamycin would improve the initial response-rate. The findings merit a controlled prospective clinical trial, comparing it with the four-drug regimen from which it has been developed. This is now
underway.
Northern Ireland Radiotherapy Centre, Belfast, and Hume Street Hospital, Dublin.
G. A. EDELSTYN
Department of Medical Statistics, Queen’s University, Belfast.
K. D. MACRAE
TREATMENT OF HYPOTHERMIA
SIR,-Iwas
very interested to
see two consecutive letters’2 in situations. There is still much hypothermia exposure discussion about the bestmethod of resuscitating hypothermic victims, whether rescued from the mountainside or from water. The majority opinion seems to be that when the victim is young, and apparently fit, fairly intensive rewarming with warm water is best, in spite of possible hazards. The exact temperature of the water is still a matter of controversy, and indeed one dilemma is that it may not be possible to measure the patient’s core temperature or the bath-water temperature, since neither a low-reading nor a normal-reading thermometer are available. The risks of rewarming to the middle-aged and the old may be great enough to contraindicate the bath method. The degree of hypothermia may also be very important, because experience in hospital with older hypothermic victims suggests that those with a core temperature below 320C are in much greater danger of dying and that management in an intensive-care unit can be lifesaving. Dr Winddescribing the successful revival (at least for a time) of a child after a long period of apnoea, mentioned that the child’s deep body temperature was severely hypothermic. Several reports of successful resuscitations of this nature suggested that hypothermia was at least partly protective: presumably the small size of the victim had allowed fairly rapid cooling, producing a hibernating state. It therefore seems that, when a small child or baby has been rescued from drowning, resuscitation may be much more successful than for older and larger individuals, even when submersion has been prolonged and the water very cold. There are still the very serious risks of cardiac and other complications during rewarming and resuscitation. There is absolutely no doubt that cold injury and hypothermia play a much more serious part in drowning incidents in this country than many people acknowledge. If somebody is in danger in cold water the current view seems to be that they should stay still and only swim to land or to a boat if the swim would be very short. There is still controversy about whether the person should keep the head above water, which would put him at risk of wind exposure, or rest the head down in the water in the drown-proofing position, only raising the head to breathe. Analysis of recent drowning statistics3 and a review of hazardous hobbies4 illustrate how harmful the effects of alcohol can be, causing confusion, precipitating the person into the water, and putting him at greater risk of hypothermia.
about
Royal Life Saving Society, Desborough House, 14 Devonshire Street, London W1N 2AT.
M. F. GREEN
SIR,-At the Alpine Club’s symposium on mountain medicine and physiology there was no question of Squadron-Leader’ Davies (Oct. 4, p. 656) being "roundly castigated" for his entertaining and stimulating presentation. The main disagreement concerned the temperature of the bath, since most authorities recommend a maximum water temperature of 44-46°C with clothes. 1-7 At the symposium cases were reported of tissue damage caused by temperatures well below 50"C, The local effect of any temperature on a body tissue depends on a balance between the total heat supplied and the heat removed. The heat supplied depends on the thermal capacity of the substance, the temperature, and whether or not a change in physical state occurs. It has been observed8 that a normothermic person can only tolerate 50"C moist heat on the lips whereas the pharynx can tolerate 57"C. Provided the larynx is bypassed the trachea can tolerate dry heat up to 350oC9 whereas a review of many experimental reports" show that steam at 94-104°C is required to produce consistent damage. This variation in tolerance to heat is due to the rate at which heat is removed which in turn is governed by the variation in blood-supply to the tissues. In hypothermia the body reacts by vasoconstriction especially in the limbs and subcutaneous tissue with a decrease in the ability to remove heat and a resulting increased susceptibility to damage. Therefore it could be a dangerous assumption that, because normothermic people can tolerate a temperature of 50°C, it is necessarily safe for hypothermic victims. It is accepted that ideal treatment for immersion hypothermia is immersion in a hot bath if the bath is immediately available. 13 4 However most patients with accidental hypothermia are at a considerable distance from any bath. By the time the patient has reached hospital the body temperature has probably stabilised,2but awkward movement or bad lifting and carrying technique during the evacuation or preparation of the bath can have a profoundly depressing effect on the vital functions of the body and may result in the death of a hypothermic victim.2 Many people feel that more emphasis should be given to immediate treatment in the field (for example, camp and insulate 2) and less to evacuation to a hot bath, the value and safety of which is being questioned, especially when exhaustion is a factor." 12 Department of Anæsthetics, Royal Infirmary, Edinburgh EH3 9YW.
E. LL. LLOYD
SCREENING FOR TUBERCULOSIS IN PATIENTS WITH PNEUMOCONIOSIS
SIR,-Dr Gordon (Nov. 15,
p. 976) assumes that patients constitute a greater risk to the compneumoconiosis munity with regard to the spread of tuberculosis than do the public in general. There is no evidence to support this and indeed the contrary may be true. It is possible that the notification and attack rate of pulmonary tuberculosis is below average in this group. It can hardly, therefore, be considered to constitute 13 an important public-health risk.
with
Manchester Chest Clinic,
352 Oxford Road, Manchester M13 9NL.
F. W. A. TURNBULL
1. Adam, J. M., Goldsmith, R. in Exploration Medicine (edited by 0. G. Edholm and A. L. Bacharach); chap. 10. Bristol, 1969. 2. Freeman, J., Pugh, L. G. C. E. Int. Anæsth. Clin. 1969, 7, 997. 3. Golden, F. St. C., Rivers, J. F. Anæsthesia, 1975, 30, 364. 4. Keating, W. R. Survival in Cold Water; p. 102. Edinburgh, 1969. 5. Mountain Rescue. PAM (Air) 299, p. 177. H. M. Stationery Office, 1968 6. Mountain Rescue and Cave Rescue; p. 44. Mountain Rescue Committee, 1972. 7 Ward, M. Mountain Medicine; chap. 25. London, 1975. 8. Lloyd, E.Ll., Conliffe, N. A., Orgel, H., Walker, P. N. Scott med
J 1972,
17, 83. 1. 2. 3.
Davies, L. Lancet, Oct. 4, 1975, p. 656. Wind, J. ibid. Royal Life Saving Society, Analysis of Drowning Statistics 1973. London,
4.
Kemp,
1975. R. Practitioner,
1975, 215, 188.
9. Moritz, A. R., Henriques, F. C., McLean, R. Am J. Path. 1945, 21, 311. 10. Lloyd, E. Ll., MacRae, W. R. Br. J. Anæsth. 1971. 43, 365. 11. Moore, R. E. Mountain Medicine and Physiology; p. 13. Alpine Club, 1975. 12. Golden, F. St. C. ibid. p. 16. 13. Cochrane, A. L., Jarman, T. F., Miall, W. E. Thorax, 1956, 11, 141.