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COLD WATER FOR SCALDS ?
1005 there were 5 cells per c.mm., all then developed hyperoesthesiee in both hands and forearms and pain at the angles of the jaw followed 12 hours later by bilateral tender parotid enlargement. By this time he had flaccid paralysis of both lower limbs with absent superficial and deep reflexes in all limbs. There were no signs of meningeal irritation, respiratory paralysis, The diagnosis of mumps or severe wasting of muscles. complicated by acute polyneuritis was hardly in doubt. A rising mumps-virus antibody titre was demonstrated later. Despite the knowledge that corticosteroids do not significantly shorten the course of the disease or produce dramatic improvement, the patient was given prednisolone 60 mg. daily in divided doses initially. The dose was reduced over the next 6 weeks. A week after beginning therapy, he was apyrexial and looked and felt better, and there was evidence of gradual return of power in his lower limbs with a reversion to normal of the superficial reflexes. The deep reflexes, though sluggish, could be elicited. He was able to walk with a broad-based waddling gait 5 weeks later and reverted to normal without any neurological deficit in 12 weeks.
globulin was positive, and lymphocytes. The patient
G. N. MENON.
London W. 11.
POISONING BY CARBON DIOXIDE SIR,-Dr. Blades’ letter,! in which he concludes that death in the case he describes was due to lack of oxygen in coma produced by carbon dioxide is interesting both because it points out an unexpected hazard and because of the conclusions reached. It does not seem necessary to suggest that carbon dioxide was the cause of the coma, when breathing an atmosphere deficient in oxygen can cause the victim to collapse into unconsciousness with little or no subjective
warning. Investigations of the atmosphere in two , wells, A and B, both of which had been the scene of fatal accidents, were recently carried out in this laboratory. In a series of 9 observations on well A the carbon-dioxide content was consistently less than 0-2%, and the oxygen content varied between 20-6% and less than 0-2% (normal 20-93%). In a series of 22 observations on well B the highest carbon-dioxide content recorded was 1-4%; the oxygen content of the same sample was 6-4%. Both these accidents were thought at first to have been due to carbon dioxide, but the post-hoc investigations inevitably lead to the conclusion that oxygen deficiency was the real 3 cause of death.2 Can Dr. Blades’ anxsthetist colleague please tell me what concentration of carbon dioxide can cause unconsciousness when added to ordinary air and not substituted for the oxygen fraction only, as in the interesting example cited by Dr. Jones
(Jan. 21, p. 158) ? The danger from carbon dioxide in underground chambers and workings has often been mentioned, but that a similar if not greater danger may arise from oxygen deficiency does not seem to be so widely appreciated. I should be interested to hear from any of your readers who have encountered instances those mentioned above, in which a low oxygen conunaccompanied by a high carbon-dioxide percentage in the atmosphere was the cause of an accident underground. such
as
tent
Water Examination Department, Department Metropolitan Water Board, The Laboratories, New River Head, London E.C.1.
letter has been shown by Dr. Blades anaesthetist colleagues, whose reply follows.-ED. L.
to
his
SIR,-Inhaling air containing a cause
concentration of 6% carbon hyperpnoea and mental confusion. Mixtures
1. Blades, A. N. Lancet, 1966, ii, 1189. 2. Windle Taylor, E. Forty-first Report of Director of Water 3.
1963-1964; p. 64. MacLean, R. D. Proc. Soc. Wat.
same
concentration of carbon-dioxide in air.
Department of Anæsthetics, West Dorset Group of Hospitals.
JOHN W. WARRICK BRIAN W. PERRISS.
EFFECT OF MATERNAL HYPOCAPNIA SIR,-Mr. MacRae (April 22, p. 896) has found that maternal hyperventilation decreases the oxygen saturation of foetal blood, and suggests that prolongation of labour in these circumstances would increase perinatal mortality and morbidity. If maternal hyperventilation is a significant cause of foetal hypoxia, it would seem more reasonable to abolish the hyperventilation rather than to resort to early delivery in every case. Hyperventilation is frequently found in cases of incoordinate labour, and in our experience it is easily abolished by the complete pain relief obtained from continuous epidural analgesia. Patients with incoordinate uterine action are usually young primigravid2e in whom a radical policy of early delivery by cassarean section has its disadvantages. Johnson and Clayton1 demonstrated that epidural analgesia increases uteroplacental blood-flow in prolonged dysfunctional labours. It now seems possible, from the information given by Mr. MacRae, that epidural analgesia may improve the condition of the foetus by abolishing maternal hyperventilation as well as by sympathetic blockade. University Department of Midwifery, Queen Mother’s Hospital, Glasgow C.3.
DONALD D. MOIR
JAMES WILLOCKS.
COLD WATER FOR SCALDS ? SIR,-Recent discussion in your columns of the value of cold water (or milk) as an emergency measure in treatment of bums has taken no account of hoemodynamic changes in the initial phases of inflammation, whether post-traumatic or infective. Dilatation of arterioles adjacent to injured tissue causes a large increase of volume flow and lateral pressure in the corresponding capillaries. Excess transudation of serum into the interstitial tissues takes place resulting in " log-jamming " of erythrocytes in the vessels thus obstructing further flow, and to a pool of stagnant transudate in the interstitial spaces beyond the drainage capacity of local lymphatic vessels. Consequent lack of adequate oxygen diffusion to adjacent cells tends to extend the area of necrosis, and the heightened pressure in distended tissue from presence of excess of undrained transudate tends to increase the sensation of pain. Application of cold, with resulting arteriolar vasoconstriction, should mitigate this pathological process; surely this is a logical procedure. For some years in my practice I have used local application of vasoconstrictor substances in all inflammatory conditions amenable to topical therapy. Admittedly there are many other factors ii the haemodynamic picture of inflammation. I have aimed at one pathological factor, and have treated it with apparent success. ALLAN CHATELIER. London S.E.13.
R. D. MACLEAN.
This
dioxide will
containing more than 9% carbon dioxide will cause gradually increasing arterial PC02’ leading to unconsciousness and finally death. Although in the case described death was due to anoxia, it is reasonable to assume that hyperventilation resulting from inhaling a gas with such a high carbon-dioxide content would lead to a rapid fall in alveolar oxygen concentration; hence unconsciousness should result sooner than when breathing the
Treat. Exam.
Examination,
1966, 15, 271.
POTASSIUM DEPLETION AND HEAT INJURY SIR,-Dr. Knochel and Dr. Vertel (March 25, p. 659) in their review of studies on heat injury in American subjects state that hypokalsemia occurs very commonly. We have not been able to confirm this in young Bantu goldminers who developed heatstroke while working underground. Serum-potassium levels measured in 16 patients within a few hours of the episode 1.
Johnson, G. T., Clayton, S. G. J. Obstet. Gynœc. Br. Emp. 1955, 62, 513.
globulin was positive, and lymphocytes. The patient
G. N. MENON.
London W. 11.
POISONING BY CARBON DIOXIDE SIR,-Dr. Blades’ letter,! in which he concludes that death in the case he describes was due to lack of oxygen in coma produced by carbon dioxide is interesting both because it points out an unexpected hazard and because of the conclusions reached. It does not seem necessary to suggest that carbon dioxide was the cause of the coma, when breathing an atmosphere deficient in oxygen can cause the victim to collapse into unconsciousness with little or no subjective
warning. Investigations of the atmosphere in two , wells, A and B, both of which had been the scene of fatal accidents, were recently carried out in this laboratory. In a series of 9 observations on well A the carbon-dioxide content was consistently less than 0-2%, and the oxygen content varied between 20-6% and less than 0-2% (normal 20-93%). In a series of 22 observations on well B the highest carbon-dioxide content recorded was 1-4%; the oxygen content of the same sample was 6-4%. Both these accidents were thought at first to have been due to carbon dioxide, but the post-hoc investigations inevitably lead to the conclusion that oxygen deficiency was the real 3 cause of death.2 Can Dr. Blades’ anxsthetist colleague please tell me what concentration of carbon dioxide can cause unconsciousness when added to ordinary air and not substituted for the oxygen fraction only, as in the interesting example cited by Dr. Jones
(Jan. 21, p. 158) ? The danger from carbon dioxide in underground chambers and workings has often been mentioned, but that a similar if not greater danger may arise from oxygen deficiency does not seem to be so widely appreciated. I should be interested to hear from any of your readers who have encountered instances those mentioned above, in which a low oxygen conunaccompanied by a high carbon-dioxide percentage in the atmosphere was the cause of an accident underground. such
as
tent
Water Examination Department, Department Metropolitan Water Board, The Laboratories, New River Head, London E.C.1.
letter has been shown by Dr. Blades anaesthetist colleagues, whose reply follows.-ED. L.
to
his
SIR,-Inhaling air containing a cause
concentration of 6% carbon hyperpnoea and mental confusion. Mixtures
1. Blades, A. N. Lancet, 1966, ii, 1189. 2. Windle Taylor, E. Forty-first Report of Director of Water 3.
1963-1964; p. 64. MacLean, R. D. Proc. Soc. Wat.
same
concentration of carbon-dioxide in air.
Department of Anæsthetics, West Dorset Group of Hospitals.
JOHN W. WARRICK BRIAN W. PERRISS.
EFFECT OF MATERNAL HYPOCAPNIA SIR,-Mr. MacRae (April 22, p. 896) has found that maternal hyperventilation decreases the oxygen saturation of foetal blood, and suggests that prolongation of labour in these circumstances would increase perinatal mortality and morbidity. If maternal hyperventilation is a significant cause of foetal hypoxia, it would seem more reasonable to abolish the hyperventilation rather than to resort to early delivery in every case. Hyperventilation is frequently found in cases of incoordinate labour, and in our experience it is easily abolished by the complete pain relief obtained from continuous epidural analgesia. Patients with incoordinate uterine action are usually young primigravid2e in whom a radical policy of early delivery by cassarean section has its disadvantages. Johnson and Clayton1 demonstrated that epidural analgesia increases uteroplacental blood-flow in prolonged dysfunctional labours. It now seems possible, from the information given by Mr. MacRae, that epidural analgesia may improve the condition of the foetus by abolishing maternal hyperventilation as well as by sympathetic blockade. University Department of Midwifery, Queen Mother’s Hospital, Glasgow C.3.
DONALD D. MOIR
JAMES WILLOCKS.
COLD WATER FOR SCALDS ? SIR,-Recent discussion in your columns of the value of cold water (or milk) as an emergency measure in treatment of bums has taken no account of hoemodynamic changes in the initial phases of inflammation, whether post-traumatic or infective. Dilatation of arterioles adjacent to injured tissue causes a large increase of volume flow and lateral pressure in the corresponding capillaries. Excess transudation of serum into the interstitial tissues takes place resulting in " log-jamming " of erythrocytes in the vessels thus obstructing further flow, and to a pool of stagnant transudate in the interstitial spaces beyond the drainage capacity of local lymphatic vessels. Consequent lack of adequate oxygen diffusion to adjacent cells tends to extend the area of necrosis, and the heightened pressure in distended tissue from presence of excess of undrained transudate tends to increase the sensation of pain. Application of cold, with resulting arteriolar vasoconstriction, should mitigate this pathological process; surely this is a logical procedure. For some years in my practice I have used local application of vasoconstrictor substances in all inflammatory conditions amenable to topical therapy. Admittedly there are many other factors ii the haemodynamic picture of inflammation. I have aimed at one pathological factor, and have treated it with apparent success. ALLAN CHATELIER. London S.E.13.
R. D. MACLEAN.
This
dioxide will
containing more than 9% carbon dioxide will cause gradually increasing arterial PC02’ leading to unconsciousness and finally death. Although in the case described death was due to anoxia, it is reasonable to assume that hyperventilation resulting from inhaling a gas with such a high carbon-dioxide content would lead to a rapid fall in alveolar oxygen concentration; hence unconsciousness should result sooner than when breathing the
Treat. Exam.
Examination,
1966, 15, 271.
POTASSIUM DEPLETION AND HEAT INJURY SIR,-Dr. Knochel and Dr. Vertel (March 25, p. 659) in their review of studies on heat injury in American subjects state that hypokalsemia occurs very commonly. We have not been able to confirm this in young Bantu goldminers who developed heatstroke while working underground. Serum-potassium levels measured in 16 patients within a few hours of the episode 1.
Johnson, G. T., Clayton, S. G. J. Obstet. Gynœc. Br. Emp. 1955, 62, 513.