The amount of vapour in the air breathed by these two guineapigs is not known, but there is no doubt that it was upwards of eight per cent.
FATAL CASES OF INHALATION OF CHLOROFORM.
If it were possible for a medical man to mistake or disregard the symptoms of approaching danger, and to go on exhibiting vapour of chloroform, diluted to a proper strength, till the death of the patient, this event would take place slowly and gradually, as in Experiment 23, related above, and every other experiment in which the air did not contain more than five per cent. of vapour. The action of the heart would survive the respiration; there would be a great tendency to spontaneous recovery, and the patient would be easily restored by artificial respiration, if it were performed whilst the heart was still acting; as I have always found it to be successful in animals under these circumstances.
In examining the recorded cases of fatal inhalation of chloroform, we shall find, however, that they have none of them taken place in this gradual manner; but that in all cases the fatal symptoms, if not the actual death, have come on very suddenly. Dr. Sibson was, I believe, the first to point out that, in the fatal cases of inhalation of chloroform, death was caused by its paralysing the heart; but he was not at that time aware of the physical conditions under which this agent may act directly on the heart. In commenting on the first four deaths from chloroform, he says:[[61]] “In all the four cases it is manifest that the immediate cause of the instantaneous death lay in the heart. The heart, influenced by the poison, ceased to contract, not from the cessation of respiration, for the heart in asphyxia will beat from one to three minutes after respiration has ceased, but from immediate death of the heart. There is no doubt a combination of causes operating to destroy the heart’s contractile power: the mental influence, the congestion in the systemic, and that in the pulmonary capillaries, will all have a material influence.” And further on he says: “We are obliged, then, from the experience of these cases, to conclude, that in man the death is usually instantaneous, and due, as every instantaneous death is, to paralysis of the heart. In animals the death is usually due to paralysis of the muscles of respiration. It is chiefly owing to the superior control of the mind over the body in man, that in him the poison acts on the heart more than in dogs.”
I had been long aware that chloroform was capable of paralysing the heart in animals; and, indeed, that sulphuric ether would do so when it could reach the heart in sufficient quantity;[[62]] and soon after Dr. Sibson’s remarks I was able to ascertain and point out the strength of the vapour which will produce this effect, and how one may avoid the risk of it, by having the vapour sufficiently diluted.[[63]] The greater number of experimenters who have killed animals with chloroform have found that the action of the heart continued after the breathing ceased; but they did not either control or ascertain the proportion which the vapours of chloroform bore to the inspired air. In Mr. Thomas Wakley’s experiments the action of the heart continued after the breathing had ceased; and this was the case in a great number of experiments performed by a Commission which reported to the Society of Emulation of Paris, in 1855.[[64]]
This Commission came to the conclusion that, in all instances in which animals are killed by chloroform, the action of the heart survives the respiration; but they might have administered chloroform to an equal number of human patients without any one of them being cut off by sudden paralysis of the heart. If animals were usually to die suddenly of paralysis of the heart, when the chloroform is given in a manner similar to what may be called its ordinary administration to patients, we should be at a loss to know how this agent could be used at all. It is only reasonable to suppose that, in experiments so conducted, that mode of death should usually be met with which would occur to the human subject, if the chloroform were continued, in the disregard of dangerous symptoms, till death should ensue. I have, indeed, been informed of several instances in which animals died in a sudden, and what was thought an unaccountable manner, whilst chloroform was given to prevent the pain and struggles which would be occasioned by physiological experiments. In these cases there is no doubt the heart was paralysed; but the experimenters were often too intent on other matters to observe the circumstance. By a proper arrangement of circumstances, however, one may produce at will the event in animals which occurs, in fact, so very rarely to a patient, although it may at any time happen if great caution, guided also by right principle, is not used.
Air, when saturated only at 60° Fah., contains 12 per cent. of vapour of chloroform, and at 70° 19 per cent. (p. 33); and 8 or 10 per cent. in the inspired air is capable, as we have seen, of causing sudden death by paralysing the heart; but in practice the air is usually far from being saturated, in passing over a handkerchief or similar material, even at the temperature at which it is inhaled; and this is generally lowered considerably by the absorption of caloric by the chloroform, as it changes its condition from a liquid to a vapour. Moreover, air strongly charged with vapour of chloroform is not easy to breathe, owing to its pungency; and the physiological knowledge and close attention of every medical man who administers this medicine causes him to withdraw it immediately on the least appearance of danger.
Case 1. The first death from chloroform was that of Hannah Greener, which occurred at Winlaton, near Newcastle, on the 28th of January, 1848. The patient was a girl of 15, who required to have the nail of the great toe removed. A similar operation had been performed on the other foot, in the previous November, in the Newcastle Infirmary, when ether was administered with a satisfactory result. The following is the account of the accident by Dr. Meggison, who administered the chloroform: “She appeared to dread the operation, and fretted a good deal: in fact, she commenced sobbing on our entering the house, and continued so until seated in the operating chair, and commencing the inhalation, which was done from a handkerchief on which a teaspoonful of chloroform had been poured. After drawing her breath twice, she pulled my hand from her mouth. I told her to put her hands on her knees, and breathe quietly, which she did. In about half a minute, seeing no change in breathing, or alteration of pulse, I lifted her arm, which I found rigid. I looked at the pupil and pinched her cheek, and, finding her insensible, requested Mr. Lloyd to begin the operation. At the termination of the semilunar incision she gave a kick or twitch, which caused me to think the chloroform had not sufficient effect. I was proceeding to apply more to the handkerchief, when her lips, which had been previously of a good colour, became suddenly blanched, and she spluttered at the mouth, as if in epilepsy. I threw down the handkerchief, dashed cold water in her face, and gave her some internally, followed by brandy, without, however, the least effect, not the slightest attempt at a rally being made. We laid her on the floor, opened a vein in her arm, and the jugular vein, but no blood flowed. The whole process of inhalation, operation, venesection, and death, could not, I should say, have occupied more than two minutes.”[[65]]
An examination of the body was made the day after death by Sir John Fife and Dr. Glover, who reported as follows:—“The body was that of a well-grown female of about fifteen years of age.... On opening the chest, the lungs were not collapsed. One or two very slight adhesions were encountered on separating them from the walls of the chest. The external appearance of both lungs, over the whole surface, but especially in the inferior portions, was that of organs in a very high state of congestion. They were mottled with patches of a deep purple, blueish, or scarlet hue. They were everywhere crepitant. Along the outer and interior border of both lungs, particularly of the upper lobe of the left lung, were several emphysematous bubbles of small size.... The pulmonary tissue was filled with bloody froth, which was also found in the interior of the bronchi, mixed with mucus. There was no appearance of hepatization. On examining the larynx and trachea, the epiglottis was found reddened at the summit, of a vermilion hue. The mucous membrane of the larynx was redder than natural—mottled with vascular patches. The sinuses of the larynx contained a good deal of dark mucus. The œsophagus was healthy. The stomach was distended with food. Some of the veins were more distinct than usual. The heart contained dark fluid blood in both its cavities: very little in the left. Its structure, and that of the great vessels near it, quite healthy. The brain, externally and internally, was more congested than usual; and the ventricles contained rather more than the usual quantity of serum.”[[66]]
Sir John Fife and Dr. Glover expressed the opinion that chloroform caused death by producing congestion of the lungs. After the further experience which has been gained respecting chloroform, this opinion of the mode in which it caused death, in the above case, would probably not now be offered. Indeed, in similar cases which have since occurred, the same opinion has not been advanced; and as the lungs were crepitant throughout, in the above case, it is probable that the congestion was not greater than is commonly met with in cases of sudden death without hæmorrhage. Dr. Simpson published his opinion, immediately after this case occurred, that it was not caused by the chloroform, but by the brandy which was given when the alarming symptoms came on; but Dr. Meggison replied that only a teaspoonful of brandy was given; that it was swallowed, though with difficulty; that there were no symptoms of choking from it; and that the girl was without pulse when it was given.[[67]]