Experiment 8. A guineapig was put into the same jar, and 52·5 grains of chloroform were introduced, being a grain and three-quarters to each 100 cubic inches of air. The chloroform evaporated in the course of four minutes, at the end of which time the guineapig was altered in its manner, as if partially inebriated. In two minutes more it was becoming drowsy. A little while afterwards it was lying down. Six minutes after the evaporation of the chloroform was complete, the guineapig made no effort when turned over by inclining the jar, but only moved its feet, as it were automatically. At the end of nine minutes, it was lying quietly and breathing naturally. When fifteen minutes had elapsed it was in the same condition, and was removed from the jar. It cried and flinched on the foot being pricked. The temperature in the axilla was 97°. In five minutes after its removal it was fast recovering, and in ten minutes was quite recovered.
Experiment 9. A guineapig was placed in the jar used in the last three experiments, and sixty grains of chloroform were introduced in the same manner, being two grains to each 100 cubic inches of air. In four minutes it was all converted into vapour, and the guineapig was beginning to be affected by it. In two minutes more it was unable to stand or walk. In five minutes from the time when the evaporation was complete, the guineapig showed no sign of sensibility when turned over by inclining the jar; the breathing was natural. At the end of ten minutes it was lying still, breathing gently forty times in the minute. At the end of fifteen minutes it was in the same condition. From seventeen to twenty minutes, it stretched out one of its hind legs several times, and was doing so when taken out, at the end of twenty minutes. It showed no sign of sensibility when pricked. The temperature in the axilla was 96°. It began to recover gradually in a minute or two, and recovered completely in from ten to fifteen minutes.
Experiment 10. A cat was placed in the same jar, and the same quantity of chloroform was introduced in the same manner. It became quite insensible in a few minutes after the chloroform was introduced; and it was allowed to remain for twenty-five minutes, when it was taken out. It was perfectly insensible to pricking, and its muscles were quite relaxed; it was breathing gently, and the pulsations of the heart were between sixty and seventy in the minute. It was immediately made the subject of another experiment of drowning whilst insensible, which need not be related in this place.
Experiment 11. Four grains of chloroform were put into a glass jar holding 200 cubic inches, and when it had evaporated and was diffused through the air in the jar, a white mouse was introduced, by momentarily removing the cover a little to one side. A minute after its introduction the mouse was lying, but it moved its legs for a quarter of a minute longer. When four minutes had elapsed, the breathing became slow, and it was taken out. It was totally insensible for the first three minutes after its removal, and recovered during the two following minutes.
Experiment 12. Thirty-two grains of chloroform were diffused through the air of a jar holding 1,600 cubic inches, being two grains to each 100 cubic inches, as in the last three experiments. A white mouse was introduced by moving the cover a little to one side for a moment. In one minute it was insensible, and did not make any effort on being rolled about by inclining the jar, but it moved its paws for half a minute longer. It remained insensible, breathing 160 times in the minute, till it was taken out at the end of five minutes. It was quite insensible to pinching. It began to walk in a minute or two. Its temperature before the experiment was 98°, and immediately afterwards was 92°. The temperature of the room was 68°.
Experiment 13. A guineapig was put into a jar holding 3,000 cubic inches, and 67·5 grains of chloroform were introduced on blotting paper suspended within the jar, being 2¼ grains to each 100 cubic inches. In four minutes, the chloroform had all evaporated, and the guineapig was becoming affected. In two minutes more, it was quite insensible. Eight minutes after the chloroform had evaporated, it was lying still, breathing forty times in the minute. During the next three or four minutes, it moved one or other of its legs occasionally. At the end of seventeen minutes, it was lying still, and the breathing was twenty-six in the minute. It was taken out at the end of twenty minutes quite insensible; in three or four minutes it began to try to walk, and in ten minutes, was quite recovered.
Experiment 14. Two white mice, one being full grown, and the other about three-quarters grown, were placed in the jar holding 1,600 cubic inches, and forty grains of chloroform were introduced on blotting paper, being two grains and a half to each hundred cubic inches. In two minutes, the chloroform had evaporated, and the mice were much excited. In another minute, they were unsteady in walking; and in a minute more, the old mouse was lying insensible, and breathing deeply and laboriously. In four minutes more, i. e., six minutes after the chloroform had evaporated, the young mouse was insensible also, but was moving one of its hind legs. In other four minutes, the young mouse was breathing by slow gasps, whilst the old one continued to breathe deeply as before. Three minutes later, i. e., thirteen minutes after the chloroform had evaporated, the old mouse had begun to gasp, and the young one was gasping only at intervals. They were removed, and recovered completely in ten minutes. The young one recovered most quickly. Their temperature, on being removed, was about 90°.
Experiment 15. A cat was put into the jar holding 3,000 cubic inches, and 82·5 grains of chloroform were introduced, being two grains and three-quarters to each hundred cubic inches. In five minutes, it had evaporated, and the cat began to stagger in its walk. In two minutes more, it was unable to stand. Five minutes after the chloroform had evaporated, the cat was breathing deeply, seventy-five times in the minute. At eight minutes, it was breathing less deeply, one hundred and seventeen times in the minute. Ten minutes after the chloroform had evaporated, the cat was quite insensible, and breathing one hundred and twenty-six times in the minute. It was now taken out. The temperature in the axilla was 98°. In half an hour after its removal from the jar, it had recovered its consciousness, but was still drowsy.
It was now put into the jar again, and the same quantity of chloroform was introduced in the same manner as before. In five minutes, it had evaporated, and the cat was again insensible. In other five minutes, it was breathing rather deeply, forty-eight times in the minute. Twelve minutes after the chloroform had evaporated, the cat was breathing in the same manner, but sixty-eight times in the minute. The breathing afterwards became shallow and feeble, and half an hour after the chloroform had evaporated, it was eighty-eight in the minute. In five minutes more, the breathing ceased. The cat was taken out of the jar, and the stethoscope was applied to the chest. The heart could not be heard to beat at first, but in a short time, the cat gave a gasp, and the heart’s action returned, and the breathing became reestablished.
Experiment 16. Forty-eight grains of chloroform were put into a jar holding 1,600 cubic inches, being three grains to each hundred cubic inches, and when it was converted into vapour and diffused through the air in the jar, a white mouse was introduced. It ran about for a minute and a half, and then it was unable to move any longer. In nine minutes and a half, the breathing was getting very slow, and the mouse was immediately removed. Before it could be got out, it appeared to have entirely ceased to breathe, but it immediately began to gasp at intervals. In a minute, the breathing improved, and soon became natural. Three minutes after its removal, the mouse began to walk in a ring, and in seven minutes, it had quite recovered.
Experiment 17. A guineapig was placed in a jar holding 1,600 cubic inches, and fifty-four grains of chloroform were introduced on blotting paper, in the manner previously explained; being three grains and three-eighths to each hundred cubic inches of air. In four minutes, the chloroform had evaporated, and become diffused through the air in the jar, and the guineapig was drowsy. In three minutes more, it was lying apparently insensible, and breathing feebly, thirty times in the minute. After this, it kicked occasionally for a few minutes. When six minutes had elapsed from the time when the chloroform had evaporated, the breathing was very feeble, and apparently performed only by the diaphragm. From fifteen to eighteen minutes, I could hardly see whether the animal was breathing or not, and it was taken out of the glass at eighteen minutes, when the breathing appeared to have ceased. The stethoscope was applied to the chest, and the sounds of the heart could scarcely be heard at first, but the breathing returned in a few seconds, and the action of the heart improved. The guineapig gradually recovered, but it was not able to walk for twenty-five minutes.
Experiment 18. Sixty grains of chloroform were introduced into the jar employed in the last experiment, being three grains and three-quarters to each hundred cubic inches of air contained in the jar. When it had evaporated, and was diffused through the air, a white mouse was introduced, whilst the lid of the jar was moved a little to one side for a moment. It ran about at first, but suddenly ceased to run, and became insensible, at the end of three-quarters of a minute. It lay breathing deeply and rapidly till two minutes had elapsed, when the respiration became slow, and it ceased at two minutes and three-quarters after the mouse was introduced. It was removed at this time, and it gasped a few seconds afterwards; this gasp was soon followed by another; the gaspings became more frequent, and in a short time, the natural breathing was resumed. In five minutes, the mouse was able to walk.
The third, fourth, and fifth of the above experiments show that one grain of chloroform to each hundred cubic inches of air suffices to induce the second degree of narcotism, or that state in which consciousness and voluntary motion are disturbed, but not entirely abolished. Now one grain of chloroform produces 0·767 of a cubic inch of vapour at 60°, when its specific gravity is 4·2; and, when the vapour is inhaled, it expands somewhat, as it is warmed to the temperature of the lungs; but it expands only to the same extent as the air with which it is mixed, and therefore the proportions remain unaltered. But air, when saturated with vapour of chloroform at 100°, contains 43·3 cubic inches in 100; and
So that if the point of complete saturation be considered as unity, 0·0177 or 1–56th, will express the degree of saturation of the air from which the vapour is immediately absorbed into the blood; and, consequently, also the degree of saturation of the blood itself.
I find that serum of blood at 100°, and at the ordinary pressure of the atmosphere, will dissolve about its own volume of vapour of chloroform; and since chloroform of specific gravity 1·483 is 288 times as heavy as its own vapour, 0·0177 ÷ 288 gives 0·0000614, or one part in 16,285, as the average proportion of chloroform by measure in the blood, in the second degree of narcotism.
It is evident, from the experiments numbered 9 to 12 inclusive, that two grains of chloroform to each hundred cubic inches of the inspired air cause a state of very complete insensibility, corresponding with what I have designated the fourth degree of narcotism; and by the method of calculation employed above we get 0·0354, or 1–28th, as representing the degree of saturation of the blood, and 0·0001228 the proportion by measure in the blood.
In experiments 6, 7, and 8, in which quantities of chloroform were employed intermediate between one and two grains to each hundred cubic inches of air, a moderate amount of insensibility was induced, corresponding very much with the state of patients during operations under chloroform.
The experiments from 13 to 18 show that quantities of chloroform, exceeding two grains to 100 cubic inches of air, have a tendency to embarrass and arrest the function of respiration, if the inhalation is continued. I have not yet been able to determine satisfactorily the exact proportion of chloroform which requires to be absorbed to arrest the respiration of animals of warm blood. I believe there is a definite proportion which has this effect, but there are two reasons why it is not so easy to ascertain it, as to ascertain the proportion which causes the minor degrees of narcotism. In the first place, the breathing often becomes very feeble before it ceases, so that the animal inhales and absorbs but very little chloroform, and remains on the brink of dying for some time. In the next place, the temperature of the body falls in a deep state of narcotism, especially in small animals; and, as the temperature falls, the amount of chloroform which the blood can dissolve from any given mixture of air and vapour increases.
Judging from the experiments numbered 14 to 18, three grains of chloroform to each hundred cubic inches of air must be very nearly the quantity which has the power of arresting the breathing when the temperature of the body is 100°; and as three grains of chloroform produce 2·3 cubic inches of vapour, and air at 100° is capable of taking up 43·3 per cent. of its volume, it follows that the blood must contain between 1–18th and 1–19th as much chloroform as it is capable of dissolving, at the time when the respiration is arrested. In the 14th experiment, the breathing of the two mice was on the point of being stopped by two and a half grains of chloroform in each hundred cubic inches of air, but during the thirteen minutes which the mice breathed the vapour, their temperature fell to about 90°. Air, when saturated with the vapour of chloroform at this temperature, contains 35 per cent., and two grains and a half of chloroform yield 1·917 cubic inches of vapour; so by a calculation similar to that made at page 68, the mice at the time when the breathing was about to cease must have absorbed 1–18th part as much chloroform as their circulating fluids were capable of dissolving.
The reader will have observed that, in the experiments related above, the mice became much more quickly affected than the guineapigs and cats. The reason of this is their quicker respiration and circulation, and much more diminutive size. Little birds, such as linnets and sparrows, are also very quickly affected by chloroform. Frogs are more slowly affected, owing to their languid respiration, unless the vapour to which they are exposed is very strong.
They can, however, owing to their low temperature, be rendered insensible by proportions of vapour too small to affect animals of warm blood; and as they have no proper temperature of their own, the amount of vapour (in proportion to the air in which they are placed) that will affect them, depends entirely on the temperature of that air.
The following experiment was several times performed on frogs with the same result, the temperature of the room being about 55°, as it was in winter.
Experiment 19. 4·6 grains of chloroform were diffused through the air of a jar of the capacity of 920 cubic inches, and a frog was introduced. In a few minutes, it became affected, and at the end of ten minutes, was quite motionless and flaccid; but the respiration was still going on. Being now taken out, it was found to be insensible to pricking: it recovered in a quarter of an hour.
In a repetition of this experiment, in which the frog continued a few minutes longer in the vapour, the respiration ceased, and the recovery was more tardy. On one occasion, the frog was left in the jar for an hour, but when taken out, and turned on its back, the pulsations of the heart could be seen. In an hour after its removal, it was found to be completely recovered.
The first of the experiments related above (page 60), showed that an atmosphere containing half a grain of chloroform to each hundred cubic inches, produced scarcely any appreciable effect on animals of warm blood; but the following calculation explains why this quantity acts so energetically on the frog, and proves that this creature is affected by chloroform according to the same law as animals of warm blood. The vapour is absorbed into the blood and lymph of the frog at the temperature of the external air, whose point of relative saturation therefore remains unaltered, both in the lungs and in contact with the skin of the animal; and as half a grain of chloroform produces 0·383 cubic inches of vapour, and air at 55° contains, when saturated, 10 per cent. of vapour; 0·0383, or 1–26th, expresses the degree of saturation of the air, and also of the blood of the frog. And this is a very little more than the quantity (0·0354 or 1–28th) which was calculated above to be the greatest amount which could be absorbed with safety into the blood of the mammalia. It must be observed, however, that the pulmonary respiration of the frog was arrested by this proportion of 1–26th as much chloroform as the blood would dissolve, whilst we calculated that it required about as much as 1–18th to arrest the breathing of animals of warm blood. It must be remembered, however, that the pulmonary respiration of frogs is a process of swallowing air, which only goes on when the creature is comparatively active. In the torpid state, the respiration takes place only by the skin, and the frog never breathes with the aid of the same muscles and nerves as mammalia and birds.
By warming a frog, together with the air in which it is placed, it is, in accordance with the law explained above, rendered comparatively proof against an amount of chloroform which would otherwise render it insensible.
Experiment 20. A frog, which had been a few days previously subjected to the experiment just narrated, was put into the same jar, which was placed near the fire, till a thermometer inside marked 75° Fah.; 4·6 grains of chloroform were then introduced, and diffused through the air in the jar. The jar was kept for twenty minutes, with the thermometer indicating the same temperature within one degree. For the first seventeen minutes, the frog was unaffected; and only was dull and sluggish, but not insensible, when taken out. Air at 75°, when saturated with vapour of chloroform, contains 22 per cent., and therefore the 0·383 per cent. of vapour, which at 55° was capable of saturating the fluids of the frog to the extent of 1–26th of what they would dissolve, was, at 75°, capable of saturating them only to the extent of 1–57th.
At one of Dr. Wilson’s Lumleian Lectures, at the College of Physicians, on March 29th, 1848, I had the honour of performing some experiments, and making some remarks, on chloroform, and I combined together two experiments on frogs and small birds, in a way which shows how entirely the effects of a narcotic vapour depend on the quantity of air with which it is mixed, and on other physical conditions.
Experiment 21. I introduced a chaffinch, in a very small cage, into a glass jar holding nearly 1,000 cubic inches, and put a frog into the same jar, covered it with a plate of glass, and dropped five grains of chloroform on a piece of blotting paper suspended within. In less than ten minutes, the frog was insensible, but the bird was not affected.
Experiment 22. I then placed another frog and another small bird in a jar containing but 200 cubic inches, with exactly the same quantity of chloroform. In about a minute and a half, they were both taken out,—the bird totally insensible, but the frog not appreciably affected, as from its less active respiration it had not had time to absorb much of the vapour.
The blood in the human adult is estimated by M. Valentin to average about thirty pounds. M. Valentin’s experiments were so conducted that this quantity must include the extra vascular liquor sanguinis, as well as the blood actually contained within the vessels. On this account, his estimate is all the better fitted for calculating the amount of chloroform absorbed, since this medicine, when inhaled gradually, passes by exosmosis through the coats of the bloodvessels into the fluid in which the tissues are immediately bathed. The above quantity of blood would contain 26 pounds 5 ounces of serum, which, allowing for its specific gravity, would measure 410 fluid ounces. This being reduced to minims, and multiplied by 0·0000614, the proportion of chloroform in the blood required to produce narcotism to the second degree (see page 68), gives 12 minims as the whole quantity in the blood. More than this is used in practice, because a considerable portion is not absorbed, being thrown out again when it has proceeded no further than the trachea, the mouth and nostrils, or even the face-piece. But I find that if I put twelve minims into a bladder containing a little air, and breathe it over and over again, in the manner of taking nitrous oxide, it suffices to remove consciousness, producing the second degree of its effects.
To induce the third degree of narcotism, or the condition in which surgical operations are usually commenced, would require that about 18 minims should be absorbed by an adult of average size and health, according to the above method of calculation; and to induce the deep state of insensibility, which I have termed the fourth degree of narcotism, would require 24 minims; whilst to arrest the function of respiration would require that about 36 minims should be absorbed.
The only direction which it is usually requisite to give beforehand, to the patient who is to inhale chloroform, is to avoid taking a meal previous to the inhalation; for chloroform is very apt to cause vomiting, if inhaled whilst there is a quantity of food in the stomach. The sickness is not attended with any danger, but it constitutes an unpleasantness and inconvenience which it is desirable to avoid. The best time of all for an operation under chloroform is before breakfast, but the customs and arrangements of this country do not often admit of that time being chosen, and it is unadvisable to make the patient fast beyond his usual hour. It answers very well to perform an operation about the time when the patient would be ready for another meal, or, if the time of operation fall two or three hours after the usual time of eating, to request the patient to make only a slender repast at that time, so as just to prevent the feeling of hunger. It is impossible to prevent vomiting in some cases with the best precautions, for the stomach occasionally will not digest when the patient is expecting a surgical operation, and the breakfast may be rejected in an unaltered state hours after it has been taken. In other cases the patient does not vomit, even when he inhales chloroform shortly after a full meal.
The most convenient position in which the patient can be placed whilst taking chloroform is lying on the back, or side, as he is then duly supported in the state of insensibility, and can be more easily restrained if he struggle whilst becoming insensible. The semi-recumbent posture on a sofa does very well, and there is no objection to the sitting posture, when that is most convenient to the operator. In that case, however, the patient should be placed in a large easy chair with a high back, so that the head as well as the trunk may be supported without any effort, otherwise he would have a tendency to slide or fall when insensible. It has been said that it is unsafe to give chloroform in the sitting posture, on the supposition that it would in some cases so weaken the power of the heart, as to render it unable to send the blood to the brain. Observation has proved, however, that chloroform usually increases the force of the circulation; and although the horizontal position is certainly the best for the patient under an operation in all circumstances, I consider that the sitting posture is by no means a source of danger, when chloroform is given, if the ordinary precaution be used, which would be used without chloroform—that of placing the patient horizontally if symptoms of faintness come on. I have preserved notes of nine hundred and forty-nine cases in which I have given chloroform to patients in the sitting posture, and no ill effects have arisen in any of these cases.
The person who is about to inhale chloroform is occasionally in a state of alarm, either about that agent itself or the operation which calls for its use. It is desirable to allay the patient’s fears, if possible, before he begins to inhale, as he will then be able to breathe in a more regular and tranquil manner. In a few cases, however, the apprehensions of the patient cannot be removed, and they subside only as he becomes unconscious from the inhalation. It has been said that chloroform ought not to be administered if the patient is very much afraid, on the supposition that fear makes the chloroform dangerous. This is, however, a mistake; the danger, if any, lies in the fear itself. Two cases will be related hereafter in which the patients died suddenly from fear, whilst they were beginning to inhale chloroform, and before they were affected by it; but the probability is that, if they had lived till the chloroform took effect, they would have been as safe as other patients who inhaled it. If chloroform were denied to the patients who are much afraid, the nervous and feeble, who most require it, would often be deprived of its benefits. Moreover, the patients would either be prevented altogether from having the advantage of surgery, or they would be subjected to the still greater fear of the pain, as well as the pain itself; for whatever undefined and unreasoning fears a patient may have when the moment comes for inhaling chloroform, he has only chosen to inhale it on account of a still greater fear of pain.
Fear and chloroform are each of them capable of causing death, just as infancy and old age both predispose to bronchitis, but it seems impossible that fear should combine with the effects of chloroform to cause danger, when that agent is administered with the usual precautions. Fear is an affection of the mind, and can no longer exist when the patient is unconscious; but the action of that amount of chloroform which is consistent even with disordered consciousness is stimulating, and increases the force and frequency of the pulse, in the same way as alcohol. I believe that no one would assert that a person would die the sooner of fright for having taken a few glasses of wine, or a small amount of distilled spirits, whatever might be the state of his health. When chloroform has been absorbed in sufficient quantity to cause unconsciousness, fear subsides, and with the fear its effects on the circulation. It is a subject of almost daily observation with me that the pulse, which is extremely rapid from some ill defined apprehension, when certain patients begin to inhale chloroform, settles down to its natural frequency after they become unconscious.
The practice I have always followed has been to try to calm the patient, by the assurance that there was nothing to apprehend from the chloroform, and that it would be sure to prevent all pain; but where it has been impossible to remove the fears of the patient in this way, I have always proceeded to remove them by causing a state of unconsciousness. It would of course be wrong to choose a moment for beginning the inhalation, when fear was producing a very marked depression of the circulation. On feeling the pulse of a gentleman, about twenty-one years of age, in March 1855, who had just seated himself in the chair to take chloroform, previous to having some teeth extracted, by Mr. Thos. A. Rogers, I found it to be small, weak, and intermitting, and it became more feeble as I was feeling it. I told the patient that he would feel no pain, and that he had nothing whatever to apprehend. His pulse immediately improved. He inhaled the chloroform, had his teeth extracted, woke up, and recovered without any feeling of depression. Now if the inhalation had been commenced in this case, without inquiry or explanation, the syncope which seemed approaching would probably have taken place, and it would have had the appearance of being caused by the chloroform, although not so in reality.
The experiments previously related show that air containing rather less than two grains of chloroform, in one hundred cubic inches, is capable of causing a state of insensibility, sufficiently deep for surgical operations; but in a creature the size of the human being, an inconvenient length of time would be occupied in causing insensibility with vapour so much diluted. About four cubic inches of vapour, or rather more than five grains of chloroform to each hundred cubic inches of air, is the proportion which I have found most suitable in practice for causing insensibility to surgical operations. In medical and obstetric cases, it should be inhaled in a more diluted form.
Dr. Simpson recommended chloroform to be administered on a handkerchief—the method in which sulphuric ether was administered by Dr. Morton, in the first case in which he exhibited that medicine. The objection to giving chloroform on a handkerchief, especially in surgical operations, where it is necessary to cause insensibility, is that the proportions of vapour and of air which the patient breathes cannot be properly regulated. Indeed, the advocates of this plan proceed on the supposition that there is no occasion to regulate these proportions, and that it is only requisite that the patient should have sufficient air for the purposes of respiration, and sufficient chloroform to induce insensibility, and all will be right.[53] The truth is, however, that if there be too much vapour of chloroform in the air the patient breathes, it may cause sudden death, even without previous insensibility, and whilst the blood in the lungs is of a florid colour. Chloroform may indeed be inhaled freely from a handkerchief without danger, when it is diluted with one or two parts by measure of spirits of wine, but the chloroform evaporates in largest quantity at first, and less afterwards, until a portion of the spirit is left behind by itself. The process, however, of inhaling chloroform from a handkerchief is always uncertain and irregular, and is apt to confirm the belief in peculiarities of constitution, idiosyncrasies and predispositions, which have no existence in the patient.[54]
The most exact way in which it is practicable to exhibit chloroform to a patient about to undergo an operation, is to introduce a measured quantity into a bag or balloon of known size, then to fill it up by means of the bellows, and allow the patient to inhale from it; the expired air being prevented from returning into the balloon, by one of the valves of the face-piece to which it is attached. I tried this plan in a few cases, in 1849, with so much chloroform in the balloon as produced four per cent. of vapour in proportion to the air. The effects were extremely uniform, the patients becoming insensible in three or four minutes, according to the greater or less freedom of respiration; and the vapour was easily breathed, owing to its being so equally mixed with the air. I did not try, however, to introduce this plan into general use, as the balloon would sometimes have been in the way of the surgeon, and filling it with the bellows would have occasioned a little trouble. It seemed necessary to sacrifice a little of absolute perfection to convenience, and I therefore continued the plan which I had already followed.
The great point to be observed in causing insensibility by any narcotic vapour, is to present to the patient such a mixture of vapour and air as will produce its effects gradually, and enable the medical man to stop at the right moment. Insensibility is not caused so much by giving a dose as by performing a process. Nature supplies but one mixture of diluted oxygen, from which each creature draws as much as it requires, and so, in causing narcotism by inhalation, if a proper mixture of air and vapour is supplied, each patient will gradually inhale the requisite quantity of the latter to cause insensibility, according to his size and strength. It is indeed desirable to vary the proportions of vapour and air, but rather according to the purpose one has in view, whether medicinal, obstetric, or surgical, than on account of the age or strength of the patient; for the respiratory process bears such a relation to the latter circumstances, as to cause each person to draw his own proper dose from a similar atmosphere in a suitable time.
The inhaler represented in the adjoining engraving is, with some slight alterations, the same that I have employed since the latter part of 1847. It is made of metal, and consists of a double cylinder, the outer space of which contains cold water, and the inner serves for the evaporation of the chloroform which the patient is to breathe. Into the inner part of the cylinder there is screwed a frame, having numerous openings for the admission of air, and four stout wires which descend nearly to the bottom of the space, and are intended to support two coils of stout bibulous paper, which are tied round them, and reach to the bottom of the inhaler. In the lower part of this paper four notches are cut, to allow the air to pass in the direction indicated by the arrows. As the quantity of chloroform which is put in should never fill the apertures or notches, the air which passes through the inhaler meets with no obstruction whatever. There is a glass tube communicating with the interior of the inhaler, and passing to the outside, to enable the operator to see when the chloroform requires to be renewed. The elastic tube which connects the inhaler to the face-piece is three-quarters of an inch in internal diameter, to allow of the passage of as much air as the patient can possibly breathe. On the introduction of the practice of inhaling sulphuric ether there was no tubing in this country fit to be breathed through; that in ordinary use was only about one-third, or three-eighths of an inch in diameter,—not more than a quarter of the proper calibre.
The face-piece, to include both the mouth and nostrils, of which that shown in the engraving is one of the modifications, is one of the greatest mechanical aids to the process of inhalation which has been contrived in modern times. Dr. Francis Sibson is its inventor. Dr. Hawkesley did indeed contrive a very similar one about the same time as Dr. Sibson,—early in 1847,—but he did not make it known. Dr. Ingen Housz made patients inhale oxygen through the nostrils by means of a bottle of India rubber with the bottom cut off; and Mr. Waugh, of Regent Street, had more recently contrived a mouth-piece to be adapted outside the lips, but the usual practice of inhalation previous to 1847, was for the patient to draw in the medicated air by means of a tube placed in the mouth. This led generally to great awkwardness at first, as the patient usually began to puff as if he were smoking a pipe; and it had the further inconvenience, in the administration of ether, that the tube dropped from the mouth, and the patient began to breathe by the nostrils, just as he was getting unconscious. The sides of the face-piece delineated in the engraving are made of thin sheet lead, which is pliable, and enables it to be adapted exactly to the inequalities of the face, and the patient can breathe either by the nostrils or mouth, just as his will, or instinct, or other nervous functions, determine.
I have introduced two valves into this face-piece, one which rises on inspiration, to admit the air and vapour from the inhaler, and closes again on expiration, and the other which rises to allow the expired air to escape. I contrived the latter valve to turn more or less to one side, as indicated by the additional line in the engraving, and thus admit more or less of the external air to dilute still further that which has passed through the inhaler, and become charged with vapour. By this means the patient can begin by breathing air containing very little vapour, and more and more of the air which has passed over the moistened bibulous paper can be admitted, as the air-passages become blunted to the pungency of the vapour.
The object of the water-bath is to supply the caloric which is rendered latent, and carried off, as the chloroform is converted into vapour, and thus to render the process of inhalation steady and uniform. Without the water-bath, the evaporation of the chloroform would soon reduce the temperature of the inhaler below the freezing point of water, and limit very much the amount of vapour the patient would inhale; and if the apparatus were warmed by the hand, the temperature would be too high, and the amount of vapour too great. A medical author of great reputation in Paris sent to inquire at what temperature I used the water-bath, and being informed, at the ordinary temperature, published his opinion that it had no effect, and might as well be left off. He appeared not to have considered the relations of heat, either to liquids or vapours.
In arranging the bibulous paper in the inhaler, it is my object to contrive that the air passing through, in the ordinary process of inhalation, and at the ordinary temperature of about 60°, shall take up about five per cent. of vapour. This quantity can be diminished, as much as is desired, by turning the expiratory valve of the face-piece a little to one side; and in winter I usually place a short coil of bibulous paper against the outer circumference of the inside of the inhaler, in addition to the central coils which are delineated.
I commonly put two, or two and a half, fluid drachms of chloroform into the inhaler at first. About a drachm of this is absorbed by the filtering paper, and the rest remains at the bottom of the inhaler; and in a protracted operation, when it is seen, by means of the glass tube, that the latter part of the chloroform has disappeared, more is added, by a drachm or so at a time, to prevent the paper ever becoming dry. Mr. Matthews, 8, Portugal Street, Lincoln’s Inn Fields, makes the inhaler. There are smaller face-pieces for children. The patient never inhales in so upright a posture as the artist has represented.
There are several other kinds of apparatus in use for the inhalation of chloroform. The most usual consist of Dr. Sibson’s face-piece more or less altered, and with a small piece of sponge placed inside. The apparatus which is in most reputation on the continent is that of M. Charrière; it consists of a glass vase with suitable valves, and a fabric for exposing a surface wetted with chloroform to the air which passes through it.
M. Duroy, of Paris, has contrived an ingenious, but very complicated, apparatus, which he calls an anæsthesimeter. The object of it is to regulate the amount of chloroform which is inhaled in a given time, and this can be varied from four to sixty drops in the minute; but the experiments which I have related show that the quantity of chloroform employed is not so important as the proportion of it in the inspired air; and although each of these circumstances has considerable influence over the other, in many cases there are conditions in which no regular relation exists between them. For instance, if the inhaler were supplied with sixty drops of chloroform per minute, these sixty drops weigh twenty grains, and produce 15·3 cubic inches of vapour; and if an adult patient were breathing the average quantity of four hundred cubic inches per minute, the air he would breathe would contain nearly four per cent. of vapour, which would answer extremely well; but if the breathing were slow or feeble, or if he should hold his breath for an interval and commence again, he might breathe air much more highly charged with vapour. Indeed it would depend on the amount of surface moistened with chloroform, the temperature of the air, and other physical conditions, whether or not the air he inhaled might not be charged with chloroform to a dangerous degree; whilst, on the other hand, if the breathing were deep and rapid, as often happens whilst the patient is getting slightly under the influence of the chloroform;—if, for instance, the patient were to breathe at the rate of 1,600 cubic inches, instead of 400, the air he would inhale would contain less than one per cent. of vapour, and he would not become insensible with the utmost supply of the anæsthesimeter, till his breathing should be moderated. M. Duroy also follows the rude and objectionable plan of using a nose clasp, and thus compelling the patient to breathe by the mouth alone.
It is advisable to request the patient to breathe gently and quietly, when he commences to inhale chloroform; in other words, to do nothing but conduct himself as if he were about to fall asleep naturally; for, if he breathes deeply, the vapour feels much more pungent than it otherwise would do, and is apt to excite coughing, or a feeling of suffocation.
In using the inhaler described above, the patient should commence to inhale with the expiratory valve of the face-piece turned on one side, and it should be gradually advanced to the required extent, over the opening it is intended to cover, as the sensibility of the lungs becomes diminished. Not only patients with phthisis or bronchitis, but many sensitive and irritable persons with sound lungs, have a great intolerance of the vapour of chloroform at first, on account of its pungency; and it is necessary to occupy two or three minutes in gradually commencing the inhalation, before the patient makes any appreciable progress towards insensibility. In administering chloroform to children also, it is desirable to begin very gently; by this means, and with a little persuasion, one generally succeeds in getting them to inhale voluntarily; although, occasionally, it is necessary to use a little force to accomplish one’s purpose.
In certain cases of the medicinal application of chloroform, and also in obstetric cases, where the pains are not severe, it is unnecessary to render the patient unconscious, but for surgical operations this is nearly always requisite. No force should ever be employed so long as the patient is conscious, unless it be to children or lunatics; but some patients become excited as soon as they are unconscious, and attempt to leave the couch, or push away the chloroform; under such circumstances, if they cannot be calmed by what is said to them, they should be held, and the vapour should be steadily and gently continued, for a minute or two, till a state of quietude is produced. By far the greater number of patients remain quiet as they become unconscious, but there is no difficulty in ascertaining whether a patient is unconscious or not. If the eyelids remain open, the countenance shows whether the patient is conscious or not; and, if they are closed, it is only necessary to touch them gently, to ascertain this circumstance. If he is still conscious, he will look at his medical man, and probably speak, or, at all events, show intelligence in his countenance.
Signs of Insensibility. The absence of consciousness, and a state of quietude, are both requisite before the commencement of a surgical operation, and they go a good way towards the preparation of a patient for it, but these symptoms may be present and the patient not be ready for an operation. The surgeon wishes to know whether he will lie still under the knife, or whether he will make a resistance and outcry which he would probably not make in his waking state. Some surgeons have recommended that the patient should be pricked with the point of a knife or some other instrument. This is not a good or satisfactory plan, however, for a person will often show no sign of feeling a slight prick, when a severe incision would rouse him to resistance. A more elegant and successful plan is to raise the eyelid gently, by placing one finger just below the eyebrow, and then to touch its ciliary border very lightly with another finger. This should not be done roughly nor too frequently, for fear of exhausting the sensibility when it is slight. Just after unconsciousness is induced, the eyelids are often closed very strongly when their margins are touched, especially in females, and there seems to be a positive hyperæsthesia; this, however, is only apparent, and arises from the control of the will being removed, whilst sensibility remains. By continuing the chloroform, the sensibility of the edges of the eyelids diminishes until, at last, they may be touched without causing winking. Under these circumstances, the most severe operation may, in almost every case, be commenced without sign of pain. I have employed this test of the sensibility or insensibility of the patient ever since chloroform has been in use, and also in the employment of ether in 1847, and I am satisfied that it affords more reliable information on this point than any other single symptom. It even indicates the amount of sensibility where a little remains; when, for instance, touching the margin of the eyelids causes very slight and languid winking, the patient will commonly flinch a little if the knife is used, but only in a manner that can be easily restrained, and will not interfere with the majority of operations. The cases, in which the indication afforded by the eyelids is not always to be depended on, are those of hysterical patients, in whom there is sometimes no winking on touching the eyelids, even when unconsciousness is scarcely induced. In such cases, one must judge by the other symptoms, and also by the length of time the patient has inhaled, the strength of the vapour, and depth and activity of the breathing. Indeed, these conditions should be observed and taken into account in every case; and all the symptoms exhibited by the patient should be watched, such as the expression of the face, the state of the breathing, and the condition of the limbs with regard to their tension or relaxation. The last is indeed sometimes relied on as the chief or sole sign whether the operation may be commenced, but it is of itself very insufficient, and even fallacious. The patient may allow his limbs to lie relaxed when he is scarcely unconscious, and not at all insensible, merely because he is not exerting his will upon them; if the arm is lifted, it may fall listlessly down again, at a time when the knife of the surgeon would rouse the patient to active resistance. Indeed, the limbs, which have been lying relaxed, may become tense as the effect of the chloroform increases, and may remain so during a short operation, in which there is no sign of pain.
Although the pulse of itself gives no indication as to how far a patient is under the influence of chloroform, it is proper to pay attention to it, not only during the first administration of the chloroform, but also throughout the operation, especially if it be attended with much bleeding. The pulse sometimes becomes intermittent or irregular during the administration of chloroform, more especially in elderly persons. This more commonly happens in the first exhibition of it, than when it is repeated during the course of an operation. I have not seen any harm from either of these conditions, but it is well to intermit the chloroform for ten or fifteen seconds, and let the patient have a few inspirations without it, if the pulse is not in a satisfactory condition. If the precaution be taken to ensure that the air the patient breathes shall never contain more than five per cent. of vapour, the pulse can never be seriously affected by the direct action of the chloroform, and the state of the breathing affords the best warning against continuing the inhalation too long at a time.
The breathing is fortunately also a sign that cannot be overlooked. It is by the breath that the chloroform enters, and it is extremely improbable that any one would go on giving the vapour after the breathing became stertorous and laboured.
The patient sometimes holds his breath after he is unconscious, and before he is insensible; this occurs under two conditions: first, after deep and rapid breathing, during which the patient seems to absorb more oxygen than is immediately required, under the circumstances; and in this condition, I have known him hold his breath for a whole minute, whilst the pulse was unaffected. The other condition in which the breathing is suspended, is when there is rigidity in the third degree of narcotism, and the respiratory muscles seem to partake of the general rigidity; the holding of the breath in these cases seldom continues so long as under the former circumstances. I do not consider that there is any danger from either of these kinds of suspension of breathing. I believe it always returns as soon as there is a want of oxygen in the system. Of course the inhaler need not be applied to the face when the patient is not breathing, and he may as well have an inspiration or two without chloroform when the breathing is renewed. It is seldom requisite to carry the effects of chloroform so far that the breathing becomes stertorous, and whenever stertor is observed, the inhalation should be suspended; under these circumstances, the patient is always insensible. In some cases, in which a little more chloroform has been inhaled than is necessary, the patient breathes for half a minute or so by the diaphragm only, and breathes in fact hardly at all. The abdomen rises and falls freely, but, from the muscles of the chest not fixing the ribs, hardly any air enters the lungs, and the face becomes rather livid; meanwhile the pulse goes on very well, and at last the patient draws a deep, sonorous inspiration, the face resumes its proper colour, and all is right again. I have not heard of any accident from chloroform commencing in this manner. This state of breathing, when it does occur, usually takes place a few seconds after the inhalation has been left off, and arises from the accumulation of the effects of the chloroform, owing to the absorption into the system of the vapour which was contained in the lungs at the time when the inhalation was discontinued.[55] This accumulation or increase of the effects of chloroform lasts for about twenty seconds; it is not dangerous unless the vapour is inhaled of too great strength, but it should be borne in mind in all cases. It may be prevented altogether, by reducing the strength of the vapour, just as the patient is getting insensible, or by giving it with intermissions of a few seconds, at this time.
The rigidity and struggling previously mentioned (pages 39 and 50) as occurring occasionally in the third degree of narcotism, more particularly in robust persons, often form a very prominent feature in the effects of chloroform; and have sometimes caused the medical man to discontinue the exhibition of chloroform, under the belief that it did not agree with the constitution of the patient, and that its further exhibition would be unsafe. The proper course to pursue is to continue the inhalation gently, till the struggling and rigidity are subdued. The patient is often insensible before these symptoms are subdued, but it is necessary to have him quiet, in order to enable the surgeon to operate with convenience and safety. I have always succeeded in subduing the involuntary struggling and rigidity, but have occasionally occupied five or six minutes in doing so. It is desirable to proceed slowly and cautiously, because, when these symptoms occur, the patient has already absorbed nearly the usual quantity of chloroform, and he often holds his breath, and then takes a sudden and deep inspiration, when he might inhale an overdose of vapour, unless it were presented to him in a well diluted state.
When the rigidity and struggling are subdued, the breathing, in some cases, becomes stertorous, and relaxation of the muscles takes place, the limbs appearing quite flaccid; but by proceeding gently, these effects may generally be avoided, and the patient becomes quiet, whilst the breathing is natural, and the muscles are in a moderate state of tension. If the operator should be afraid to proceed with the exhibition of chloroform, on account of the violence of the muscular spasm and rigidity, it will be satisfactory to him to know that, if the inhalation is resumed in a few minutes, these symptoms will be less violent than at first.
Struggling and rigidity are less likely to occur, when chloroform is administered slowly, than under opposite circumstances; but it is impossible to prevent these phenomena altogether in certain patients. After they are once subdued, they but very rarely recur during the operation; the patient, in most cases, seems to take on, when he is subdued by the chloroform, the same relation to it that women, children, and persons in a state of debility have from the first. M. Chassaignac has called this condition one of tolerance of the chloroform. It is a condition in which the patient bears both the chloroform and the operation very comfortably; but tolerance of a medicine is generally meant to imply that the patient can take it in larger quantity than before. But this is the reverse of what occurs when the patient is in a tranquil state from chloroform; he has already absorbed a considerable quantity, which has most likely penetrated deeply into the tissues, and he certainly does not require, and could not bear, so much as in the earlier stage of inhalation, where he is restless and breathing more quickly, and thus exhaling and getting rid of the chloroform at a greater rate.
It might be a question whether the absence of muscular excitement, in a number of cases, does not arise from the circumstance that anæsthesia, or absence of common sensibility, is obtained, and the operation performed, at a stage of narcotism anterior to that in which the muscular rigidity and spasm occur. This is true in a few cases, but I am satisfied by careful observation that, in the greater number of instances in which muscular excitement is absent, it would not occur at all, though the inhalation should be pushed to the most extreme degree. Many animals also are killed by chloroform without the least excitement of the muscular system occurring at any part of the process.
The pupils of the eyes are dilated in the deep state of insensibility which I have called the fourth degree of narcotism, but it is desirable to avoid carrying the effects of chloroform to this extent. They are occasionally dilated, however, under the slighter effects of chloroform, and even as the patient is recovering from its effects. In the third degree of narcotism, when the eyes are turned upwards, the pupils are usually, if not always, contracted; there seems to be a consentaneous action in the iris and the muscles which turn up the eye. The pupils seem also to be less sensitive to light, when the patient is insensible from chloroform, than at other times. This is all the information I am able to give about the pupils. Some writers have entered into a good deal of detail about the pupils, but their statements are very conflicting. The pupils are acted on by other causes, both external and internal, as well as the chloroform. The amount of light has great effect on them; and I have seen them remain dilated for some time after the chloroform was discontinued, and then suddenly contract, as the patient began to use his eyes. Even if definite laws could be ascertained with regard to the action of chloroform on the pupils, in different doses, and under different conditions, there would be some difficulty in applying them during the administration of the vapour, as the patient cannot be made to direct his eyes to or from the light. There is also some difficulty in making correct observations on the pupils. Very often, when I am exhibiting chloroform, one of the bystanders lifts the patient’s eyelid and makes a remark on the state of the pupil, and, on my looking in the face of the speaker, I often have occasion to tell him that his own pupils are quite as much dilated, or contracted, as the case may be.
With regard to the position of the eyes, they are usually turned upwards in the third degree of narcotism, as I have already said, but in a considerable number of instances they retain their usual position all through the inhalation. In a few cases, they are turned downwards, the pupils being almost hid under the lower eyelids, and causing a curious expression. I have noticed this most frequently in children of ten to fourteen years of age. I have scarcely ever seen temporary strabismus under the influence of chloroform.
The length of time which it is most desirable to occupy in the administration of chloroform, before the commencement of an operation, is about two minutes in infants, three minutes in children, and four or five minutes in adults. Circumstances occasionally occur, however, to lengthen these periods. The time during which the adult patient usually remains conscious whilst inhaling, is about two and a half minutes, but this period is sometimes prolonged from the nervousness of the patient, or his intolerance of the pungency of the vapour. Again, when unconsciousness is induced, there is, in many cases, an increased flow of saliva; and although this usually causes no impediment, the patient sometimes keeps making efforts of deglutition which very much retard the inhalation; and, at other times, he holds his breath, with his mouth full of saliva, as if he had some obscure idea of disposing of it in a suitable manner.[56] The delay which often arises from the struggling and rigidity has been already mentioned; but notwithstanding all these circumstances, it hardly ever takes more than seven or eight minutes to make a patient sufficiently insensible.
I have indeed met with a few cases in which a longer time has been occupied, but there has always been a physical reason for it. I have never had occasion to attribute the delay to any idiosyncracy, or great peculiarity in the patient, but only to the circumstance that the vapour did not enter the lungs in sufficient quantity within a given time. I have had under my care several patients who, it was supposed, were not susceptible of the effects of chloroform, or were, at least, very difficult to bring under its influence, as previous attempts had failed. It so happens, however, that I have had no difficulty whatever with any of these cases.
Two or three female patients who were about to undergo some trifling operation, preferred to leave off before they were unconscious, on account of unpleasant sensations in the head or chest, and to have the operation performed without the full effects of the chloroform; but there is no doubt the agent would have acted well enough if it had been continued.
The following case will show that chloroform may be inhaled with advantage in cases which at first seem very unfavourable. I received a note in 1849 from a medical man in the country, in which he says:—“I have now a young lady under my charge, from whom I am about to remove a tumour attached to the ear. She is anxious to take chloroform, and by the desire of herself and mother, I yesterday administered it by way of trial, but only to what would be termed the second, and perhaps you would say, the first degree. She lost some sensation, but was quite conscious, and spoke. She felt giddy; there was tumultuous beating of the heart, and a much accelerated pulse, with a dilated pupil; a perfect coldness over the whole skin, with an equally cold perspiration; and, during recovery from this slight effect, severe tremors of the whole body, so much so as to shake the couch on which she was lying. From this state she did not recover for nearly an hour. She complained of great giddiness and oppression at her chest. She is a healthy-looking, florid girl, but not strong, and has had, from time to time, severe spasm affecting her chest, so much so as to take away her breath. I have thus endeavoured to give you an outline of the constitution of my patient, how she had suffered, and what were the effects of the small dose of chloroform given by an inhaler. I never witnessed such extreme cold, tremor, or such tumultuous action of the heart; and am therefore anxious for the opinion of one who has administered chloroform under a greater variety of circumstances than myself, and to learn whether the symptoms I have described are sufficient to deter one from giving a sufficient dose to cause entire suspension of consciousness. My own impression is that they are sufficient to deter, but the patient and her friends being both anxious it should be inhaled if possible, I shall only be too glad to hear that you have witnessed like symptoms, and that you do not consider them sufficient indications of danger to deter me from its careful administration in the case.”
I advised that the chloroform should be administered again, and continued steadily till the patient should become insensible; expressing my belief that the unpleasant symptoms would subside as unconsciousness was induced. I received a reply to the effect that the operation had been performed very successfully under the influence of chloroform, although the vapour had an exciting effect for some time.
Repetition of Chloroform during an Operation. The first application of chloroform often suffices for an operation, if it be of short duration, without repeating the inhalation. In a few cases the patient remains insensible to the knife for three minutes after the inhalation is left off, but this is an exception; and one cannot, at all events, make sure of this prolonged effect of chloroform, without producing a deeper state of narcotism than is desirable. More usually, if the operation lasts more than a minute or two, it is necessary to repeat the inhalation; it is, indeed, generally desirable to let the patient have a few inspirations of air charged with chloroform vapour every half minute or so, whilst the operation continues, in order to keep up the insensibility. When the surgeon is cutting in the neighbourhood of important parts, it is desirable to prevent any sign of sensibility, and to keep repeating the chloroform so as to keep up the coma, without, however, causing embarrassment of the breathing, or wide dilatation of the pupil. In the greater number of operations, however, it is better to wait till there is some sign of sensibility, such as a slight cry or tendency to flinch, before the inhalation is resumed; and then a few inspirations of well diluted vapour make the patient quiet again.
As soon as a patient has ceased to inhale, the chloroform begins to exhale in the form of vapour from the blood as it passes through the lungs. It cannot be detected by the sense of smell, after the lungs have been emptied, by two or three expirations, of the vapour they contained at the moment when the inhalation was discontinued; but I have detected it by chemical means, after consciousness had returned. The chloroform exhales in greatest quantity at first, and the patient usually recovers his sensibility and consciousness in the time which it ought to take for the chief part of the chloroform to be exhaled, according to mechanical principles; as will be explained in treating of the modus operandi of this agent. The last traces of the chloroform of course exhale more slowly, and a very minute and insignificant quantity may remain for a considerable period in the system, not only of the patient, but of anyone who was standing by whilst he inhaled.
It is probable that a small portion of chloroform passes out by other channels than that of the expired air: the latter, however, offers such a ready and expeditious outlet, that the quantity excreted in any other way is, most likely, very minute. I have on four occasions examined urine passed after the inhalation of chloroform, by boiling it in a flask, and passing the vapour, first through a red-hot tube, and afterwards through a tube moistened inside with solution of nitrate of silver, and I only on one occasion obtained a very slight precipitate of chloride of silver.
The patient usually becomes conscious within five minutes after the inhalation has been discontinued. After a short inhalation, for a very brief operation, consciousness sometimes returns immediately, and after a prolonged inhalation the recovery of consciousness is sometimes retarded till ten minutes have elapsed. Old people are often longer than others in awaking from the effects of chloroform, owing, no doubt, to their slower breathing and circulation. Children, on the other hand, usually recover very quickly from its direct effects; but they often lapse into a natural sleep which lasts a considerable time—even for hours if they are not disturbed, and if the operation has left no painful wound or other cause of uneasiness.
It is desirable not to talk to the patient as he is recovering from the effects of chloroform, but to leave him to collect his ideas, and not speak to him till he is quite conscious, or makes some remark or inquiry himself. If not prevented by the medical attendant, the friends of the patient often address him the moment he opens his eyes; and the words they generally use are of a very equivocal meaning to one who cannot understand their application. They usually say “It’s all over”, which very often has the effect of raising an indefinite feeling of alarm in the patient; for, until he has had time to recover his memory, the operation he was to undergo is generally the farthest thing from his mind. When left to himself the patient usually recovers from the insensibility in a very tranquil manner. If he has not been moved whilst insensible, and awakes in the position in which he fell asleep, he supposes, very commonly, that he has not been asleep at all; and in a great number of instances will contend this point very stoutly, even after a protracted operation, and assert that the chloroform has not taken effect. It is as well to let him remain in this conceit for a while, or even till he finds out the mistake himself; for, if reminded of the pain they have been spared, just on waking after an operation, persons are liable to be excited by emotions of pleasure and gratitude; but a few minutes later, when the effects of the chloroform have more completely subsided, they are better able to control their emotions. A few persons wake with a full recollection of the preceding circumstances, and inquire if the operation is done; whilst others, on first awaking, are still entirely occupied with the subject of their dreams.
The greater number of patients who inhale chloroform have to remain in bed on account of the operation which has been performed, but after minor operations, the patient is sometimes able to walk away within five minutes; although more frequently there is a little languor or feeling of fatigue for half an hour or so; and it is desirable in all cases for the patient to sit or lie quietly for this space of time, if not longer, before he makes any mental or bodily exertion, even if he feels quite well.
Sickness. The chief drawback to the benefits conferred by chloroform is the sickness which in many cases follows its use. It is most frequent when the inhalation takes place soon after a meal, and some of the precautions which are requisite in order to avoid this symptom, or render it as rare as possible, have already been described (p. 74); but it occurs in certain cases, notwithstanding the best measures which may be used for its prevention. Moving the patient as the effects of the chloroform are subsiding is very apt to excite vomiting when it might not otherwise occur; it is therefore desirable, when convenient, to allow the patient to lie for half an hour or so, without moving his head from the pillow. By this means, even when a feeling of nausea is present, it often subsides without the occurrence of vomiting. It is advisable also not to give the patient anything to eat or drink till about an hour after the inhalation, and, as a general rule, not even then, unless there is some inclination for it; for if anything is taken into the stomach before the effects of the chloroform have entirely subsided, it is apt to excite vomiting. Even medicine, such as an opiate, is better delayed for an hour or upwards, unless there is an urgent necessity for giving it sooner. Severe faintness from loss of blood during an operation of course forms an exception to this rule; in such a case brandy and water should be given, and repeated if it should be vomited.
These rules respecting food are, moreover, meant to apply only to the use of chloroform in surgical operations, and not to its employment during labour. Under the latter circumstances, one allows the patient all the nourishment that is desirable, intermitting the inhalation now and then for the purpose. And chloroform, given in the moderate way in which it is employed in labour, hardly ever causes sickness, but often alleviates it when present from physiological causes.
The sickness induced by chloroform usually subsides of itself in the course of an hour, or even less; I, therefore, think it advisable not to do anything for it during this space of time. When it has continued beyond this period, I have found a little cold brandy and water to remove it in most cases; and when the tendency to vomit still remained after a few hours, I have seen it removed by a dose of opium. Effervescing draughts have not appeared to be of service in the sickness from chloroform, and sal volatile and draughts of warm water seem injurious. It is desirable for the patient to make no effort, but only to vomit if obliged to do so.
Several cases have come within my knowledge, in which the sickness has continued for two or three days after every thing that was taken into the stomach. These cases have not been under my care, but under that of the surgeon. I have been informed, however, that all the usual remedies for sickness were applied for the time mentioned above without success. The cases in which the sickness lasts so long form but a very small portion of the whole number in which chloroform is administered, and they chiefly occur in persons who are subject to attacks of vomiting from slight causes, or, as they say, to bilious attacks.
The most usual time for the vomiting to commence is when the inhalation has been discontinued, and the effects of the chloroform are passing of. In many cases, it occurs before the patient has become quite conscious, and he does not know that it has occurred unless he is told. In a few cases, especially where there is a good deal of food in the stomach, the vomiting comes on before the operation is finished, or even before it is commenced. When vomiting comes on during an operation, it is apt to interfere with the inhalation, and it is sometimes difficult to prevent the patient from waking; but this can be accomplished by wiping the patient’s mouth, and reapplying the chloroform, the moment the act of vomiting ceases. In many cases, however, the sickness does not come on till the patient is quite awake, and perhaps, even then, not until he moves. I believe that the sickness which is due to chloroform always commences within an hour or two, or at the farthest, just after the first food which is taken. I have known vomiting attributed to the chloroform which did not occur till the following day, but I ascertained that a dose of opium had been taken at night, and it was to this that the sickness was probably owing. In those cases where the chloroform does cause sickness in the first instance, it is not always the cause of all the vomiting which the patient may suffer. If the patient becomes infected or is inoculated with the poison of erysipelas or hospital gangrene at the time of the operation, he will probably be attacked with vomiting a day or two afterwards; and if sickness has already been caused by the chloroform, that which is due to disease may appear to be a continuation of it.
Soon after the introduction of chloroform, I administered it to a gentleman, aged about 55, whilst a fatty tumour was removed from the nape of the neck. It did not turn out as fatty tumours usually do, but required to be dissected out. The patient had taken a meal before the operation, and vomited freely afterwards. On his visit the next morning, the surgeon thought his patient going on well. Vomiting returned, however, and the patient became affected with partial stupor and delirium, which his friends attributed to the chloroform. He became covered with an eruption of erysipelas over a great part of the body, had a very rapid pulse with great depression, and died on the fifth day. An examination after death showed that there had been diffuse cellular inflammation around the seat of the operation. A surgeon who assisted at the operation on the above patient, and also at the post-mortem examination, removed an encysted tumour from the scalp of an old lady the day following the latter event. This operation was performed without chloroform, but the patient was attacked with erysipelas and diffuse cellular information, and died in three or four days.