Source: Snow, John. Medical Times, vol. 22, Dec. 14, 1850, p. 635. [letter to ed.].

Dr. Snow on chloroform

(To the Editor of the Medical Times)

Sir,--I shall be obliged if you will allow me space for a few observations in reply to some remarks in the Clinical Lecture of Mr. Bransby Cooper, reported in last week's Medical Times, respecting the effects of chloroform on a patient on whom he operated for the removal of a large tumour of the thigh. My object is merely to prevent mistaken impressions which might limit the application of the greatest boon that medical science has conferred on the present generation; and I feel confident that Mr. Cooper himself will be glad that I have given expression to my opinions, though they differ somewhat from his own. The operation in question did not appear to me to be a protracted one, but rather the reverse, considering its magnitude. The quantity of chloroform inhaled was between two and three fluid drachms. I have often been present at more protracted operations, at which a much greater amount of chloroform was consumed. The collapse, as Mr. Cooper terms it, undoubtedly arose from the loss of blood, and had no connexion with the chloroform. On a surgeon who stood near to me remarking on the faintness of the patient, I observed that it would have occurred without the chloroform, to which he fully assented; and I thought that such was the opinion of every one present, but have, it seems, been mistaken. I gave wine to the patient at the conclusion of the operation, certainly with no view of removing the effects of the chloroform, for I believe that these agents have a very similar action.

With respect to the loss of blood being small, if the term be used in comparison with what might be expected in such an operation, I can in some measure agree to it; but I consider that it was large compared with that which usually takes place in operations. Every one who has read the description of the operation will perceive that the hæmorrhage would be likely to be considerable, and, at all events, it was such as to tell very decidedly on the pulse and the colour of the lips. The fact of the hæmorrhage being chiefly venous, would not lessen its after effects, though it might diminish the danger at the moment. The large wound from the operation would also assist in keeping up the collapse; for, although chloroform usually leaves a soothing effect for some little time, the system begins to feel, more or less, the effects of any injury that it may have sustained as soon as the insensibility passes off. As for the reaction, which Mr. Cooper states did not take place in his patient till between ten and eleven at night, it was the reaction from the operation, none taking place from chloroform, as it is not required. I have seen a patient upwards of eighty years of age inhale six fluid drachms of chloroform for neuralgia in the course of the evening, and yet there was neither depression nor reaction from its use, the pulse being scarcely affected by it. The patient merely recovered from his insensibility after each inhalation. The only depression which I have seen produced by it, is that connected with a feeling of sickness which it sometimes occasions. That chloroform, when incautiously given, is capable of causing sudden death, must be freely admitted; but, used with due care, its effects quickly pass off; and under no circumstances is protracted collapse one of those effects. Its action, on the other hand, is rather that of a stimulant; a tincture of chloroform having been in use for many years, under the name of chloric ether, as a diffusible stimulant and antispasmodic.

All those who were in the Profession before the discovery of inhalation for causing insensibility to pain, must remember that syncope was by no means uncommon at operations, whilst now the reverse is the case; and in some hospitals where chloroform is constantly used, brandy, wine, and ammonia have altogether ceased to be kept in the operating theatres. Out of many hundred operations that I have witnessed under the influence of chloroform, I can only remember five in which spirits, [illegible word] ammonia were given on the operating table, and only two in addition to Mr. Cooper's case, in which there was severe and protracted collapse. In these two cases the operations were of unusual magnitude. I have, however, heard and read of operations performed years ago in which the patients died on the table, and that, occasionally, when neither the loss of blood nor the injury inflicted seemed adequate to cause such a result; and if, now and then, we still see great collapse following an operation, we ought, rather than blame the chloroform, to consider whether the event might not have been still more disastrous if the patient had had to suffer the pain of the operation.

Mr. Cooper describes the subsequent state of the patient as follows:--

"During the next two days her condition was very precarious. There was a quick, feeble, and at times fluttering pulse, dry and parched tongue, excessive thirst, hot and burning skin, frequent vomiting, and occasional rigors, attended with no salutary action whatever in the wound, which discharged a greenish exceedingly offensive, watery fluid. A favourable change, however, then took place."

Respecting these symptoms he says:--

"I have some little hesitation in speaking confidently or decidedly as to the true cause of her symptoms since the operation, namely, whether they were simply and purely the effect of loss of blood on an irritable subject, or whether they were the consequences of hæmorrhage modified by the influence of chloroform. I am disposed to incline to the latter however, for she certainly sustained but little loss of blood during the operation, and what she lost was chiefly venous; and, I must say, her condition has appeared to me rather to be produced by the influence of some poison, some irritating or abnormal constituent in the blood, than by the influence of hæmorrhage."

Now, any medicine may be called a poison when spoken of in a disparaging sense. Chloroform is a narcotic of the least irritating kind. In point of strength it is situated between opium and alcohol, but it differs from both of these agents in the short time which it remains in the blood. On the day subsequent to the operation, chloroform could only remain in the blood in almost infinitesimal quantity, whilst the opium, if not the alcohol, she had taken, would probably remain in comparatively much larger quantity. Experience, however, indicates that the symptoms (unless it were the single one of vomiting) could arise from none of these "poisons," and that, if due to a poison at all, they must have been caused by some of the morbid poisons which are apt to infest an hospital--such as that of erysipelas. The vomiting was most likely due either to the same cause as the other symptoms, or to the opium taken on the evening after the operation, but, whatever its cause, it was probably not injurious.-- I am, Sir, etc.,

54, Frith-street, Soho. John Snow.

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