12. In those cases which ended fatally, blood-letting restored, or preserved the use of reason, rendered death easy, and retarded the putrefaction of the body after death.
I shall now mention some of the circumstances which directed and regulated the use of this remedy.
1. Where bleeding had been omitted for three days, in acute cases, it was seldom useful. Where purging had been used, it was sometimes successful. I recovered two patients who had taken the mercurial purges, whom I bled for the first time on the seventh day. One of them was the daughter of Mr. James Cresson, the other was a journeyman ship-carpenter at Kensington. In those cases where bleeding had been used on the first day, it was both safe and useful to repeat it every day afterwards, during the continuance of the fever.
2. I preferred bleeding in the exacerbation of the fever. The remedy here was applied when the disease was in its greatest force. A single paroxysm was like a sudden squall to the system, and, unless abated by bleeding or purging, often produced universal disorganization. I preferred the former to the latter remedy in cases of great danger, because it was more speedy, and more certain in its operation.
3. I bled in several instances in the remission of the fever, where the pulse was tense and corded. It lessened the violence of the succeeding paroxysm.
4. I bled in all those cases in which the pulse was preternaturally slow, provided it was tense. Mr. Benj. W. Morris, Mr. Thomas Wharton, jun. and Mr. Wm. Sansom, all owe their lives probably to their having been bled in the above state of the pulse. I was led to use bleeding in this state of the pulse, not only by the theory of the disease which I had adopted, but by the success which had often attended this remedy, in a slow and depressed state of the pulse in apoplexy and pneumony. I had moreover the authority of Dr. Mosely in its favour, in the yellow fever, and of Dr. Sydenham, in his account of a new fever, which appeared in the year 1685. The words of the latter physician are so apposite to the cases which have been mentioned, that I hope I shall be excused for inserting them in this place. “All the symptoms of weakness (says our author) proceed from nature's being in a manner oppressed and overcome by the first attack of the disease, so as not to be able to raise regular symptoms adequate to the violence of the fever. I remember to have met with a remarkable instance of this, several years ago, in a young man I then attended; for though he seemed in a manner expiring, yet the outward parts felt so cool, that I could not persuade the attendants he had a fever, which could not disengage, and show itself clearly, because the vessels were so full as to obstruct the motion of the blood. However, I said, that they would soon find the fever rise high enough upon bleeding him. Accordingly, after taking away a large quantity of blood, as violent a fever appeared as ever I met with, and did not go off till bleeding had been used three or four times[76].”
5. I bled in those cases in which the fever appeared in a tertian form, provided the pulse was full and tense. I well recollect the surprise with which Mr. Van Berkel heard this prescription from me, at a time when he was able to walk and ride out on the intermediate days of a tertian fever. The event which followed this prescription showed that it was not disproportioned to the violence of his disease, for it soon put on such acute and inflammatory symptoms as to require six subsequent bleedings to subdue it.
6. I bled in those cases where patients were able to walk about, provided the pulse was the same as has been mentioned under the fourth head. I was determined as to the propriety of bleeding in these two supposed mild forms of the fever, by having observed each of them, when left to themselves, frequently to terminate in death.
7. I paid no regard to the dissolved state of the blood, when it appeared on the first or second day of the disease, but repeated the bleedings afterwards in every case, where the pulse continued to indicate it. It was common to see sizy blood succeed that which was dissolved. This occurred in Mr. Josiah Coates, and Mr. Samuel Powel. Had I believed that this dissolved state of the blood arose from its putrefaction, I should have laid aside my lancet as soon as I saw it; but I had long ago parted with all ideas of putrefaction in bilious fevers. The refutation of this doctrine was the object of one of my papers in the Medical Society of Edinburgh, in the year 1767. The dissolved appearance of the blood, I suppose to be the effect of a certain action of the blood-vessels upon it. It occurs in fevers which depend upon the sensible qualities of the air, and in which no putrid or foreign matter has been introduced into the system.
8. The presence of petechiæ did not deter me from repeating blood-letting, where the pulse retained its fulness or tension. I prescribed it with success in the cases of Dr. Mease, and of Mrs. Gebler, in Dock-street, in each of whom petechiæ had appeared. Bleeding was equally effectual in the case of the Rev. Mr. Keating, at a time when his arms were spotted with that species of eruptions which I have compared to moscheto-bites. I had precedents in Dr. De Haen[77] and Dr. Sydenham[78], in favour of this practice. So far from viewing these eruptions as signs of putrefaction, I considered them as marks of the highest possible inflammatory diathesis. They disappeared in each of the above cases after bleeding.