3. It was said, that blood-letting was prescribed indiscriminately in all cases, without any regard to age, constitution, or the force of the disease. This is not true, as far as it relates to my practice. In my prescriptions for patients whom I was unable to visit, I advised them, when they were incapable of judging of the state of the pulse, to be guided in the use of bleeding, by the degrees of pain they felt, particularly in the head; and I seldom advised it for the first time, after the second or third day of the disease.
In pneumonies which affect whole neighbourhoods in the spring of the year, bleeding is the universal remedy. Why should it not be equally so, in a fever which is of a more uniform inflammatory nature, and which tends more rapidly to effusions, in parts of the body much more vital than the lungs?
I have before remarked, that the debility which occurs in the beginning of the yellow fever, arises from a depressed state of the system. The debility in the plague is of the same nature. It has long been known that debility from the sudden abstraction of stimuli is to be removed by the gradual application of stimuli, but it has been less observed, that the excess of stimulus in the system is best removed in a gradual manner, and that too in proportion to the degrees of depression, which exist in the system.
This principle in the animal economy has been acknowledged by the practice of occasionally stopping the discharge of water from a canula in tapping, and of blood from a vein, in order to prevent fainting.
Child-birth induces fainting, and sometimes death, only by the sudden abstraction of the stimulus of distention and pain.
In all those cases where purging or bleeding have produced death in the yellow fever or plague, when they have been used on the first or second day of those diseases, I suspect that it was occasioned by the quantity of the stimulus abstracted being disproportioned to the degrees of depression in the system. The following facts will I hope throw light upon this subject.
1. Dr. Hodges informs us, that “although blood could not be drawn in the plague, even in the smallest quantity without danger, yet a hundred times the quantity of fluids was discharged in pus from buboes without inconvenience[79].”
2. Pareus, after condemning bleeding in the plague, immediately adds an account of a patient, who was saved by a hæmorrhage from the nose, which continued two days[80].
3. I have before remarked that bleeding proved fatal in three cases in the yellow fever, in the month of August; but at that time I saw one, and heard of another case, in which death seemed to have been prevented by a bleeding at the nose. Perhaps the uniform good effects which were observed to follow a spontaneous hæmorrhage from an orifice in the arm, arose wholly from the gradual manner in which the stimulus of the blood was in this way abstracted from the body. Dr. Williams relates a case of the recovery of a gentleman from the yellow fever, by means of small hæmorrhages, which continued three days, from wounds in his shoulders made by being cupped. He likewise mentions several other recoveries by hæmorrhages from the nose, after “a vomiting of black humours and a hiccup had taken place[81].”