Purulent discharge from the ears, deafness, spasmodic contraction of the extremities, convulsions, all depend upon certain states of the brain, and will be noticed when these states are spoken of. Numerous maladies arising from various degrees and complications of disease in the lungs, heart, pleura, viscera of the abdomen and investing membrane, not belonging to fever, but adding to its evils, are found on examination after death, which often fully account for anomalous symptoms that aggravated the case during life. Of these mention will be made in the proper place.
CHAPTER VI.
OF THE PATHOLOGY OF FEVER.
Importance of connecting the Symptoms with the States of the Organs: Pathology of Fever comprehends the Morbid Changes that take place in the Solids and Fluids of the Body. 1. General Pathology of the Solids, exhibiting a collective View of the Morbid Appearances in the Head, Thorax, and Abdomen. Cases illustrating such Morbid Appearances in each of these Cavities. 2. Pathology of the Fluids.
The preceding history of the symptoms of fever can be of no real use unless it be possible to connect it with the events of which those symptoms are the signs. The events consist of certain morbid changes which take place in the series of organs already enumerated. We arrive at the knowledge of these events first by noting the symptoms which occur during life, and their order of succession: and, secondly, by examining the condition of the organs after death in the fatal cases: a comparison of the symptoms, as previously observed, with the state of the organs as subsequently ascertained, teaches us what the symptoms indicate. By carefully observing the symptoms in a large number of cases, we at length become acquainted with all the important symptoms that arise: by carefully examining the organs after death in a large number of cases, we gradually learn all the important changes in structure which they undergo: and by comparing, in all cases, the morbid symptoms with the altered states, we acquire in the end the power of ascertaining, with a high degree of probability, the presence of an event which we cannot see, by the presence of its sign which we can see.
In proportion as our knowledge becomes perfect, we are thus enabled, during life, and at the bed-side of the patient, to see what is going on within his brain, within his lungs, and within his intestines, with as much distinctness and certainty as we could were the cases in which these organs are enclosed, and the organs themselves transparent. The highly interesting and important fact demonstrated by the examination, in the manner of which we have just spoken, of large numbers of fever patients is, that the changes which take place in the organs are uniform; that the symptoms by which these changes are denoted are likewise uniform, and therefore, that it is possible to arrive at a perfect knowledge of the phenomena of fever.
The present state of our knowledge, it must be confessed, is far from being perfect. To a certain extent, however, it is even already sufficiently perfect to afford the physician an invaluable guide in the conduct of his practice; and the steps that are wanting to complete the knowledge we possess (as far as human knowledge can be complete) future labour and perseverance will assuredly supply.
The pathology of fever comprehends the morbid changes that take place in the solids and the fluids of the body. It is probable that the changes in the fluids are wholly dependent upon those which take place in the solids, although the vitiation of the former must necessarily react upon, and increase the derangement of the latter. If it be true, as is highly probable, that the changes in the solids are beyond all comparison of the greatest importance, as not only antecedents, but invariable antecedents, or causes, it may be considered fortunate that our knowledge of their diseases is so much more advanced than our knowledge of the diseases of the humours. The morbid changes of the solids are ascertained with a great degree of exactness, it may almost be said with a great degree of perfection; while those which occur in the fluids are almost wholly unknown. Until very recently physicians satisfied themselves with framing conjectures about their corruption; and knowing with certainty no one vice that they possess, they attributed to them a thousand. Attention is now awakened to the subject: investigation is going on: and before long we shall probably know, with some degree of precision, whether any changes really take place, and what they are: but the researches which have hitherto been made are so few and so imperfect, that it can hardly be said that a single point is satisfactorily made out and firmly established.
In laying before the reader the pathology of the solids, as far as it is yet ascertained, it is my most anxious wish to enable him constantly to make for himself, as he proceeds, the association between the morbid appearances that are found after death, and the symptoms that were present during life. For this reason every case that is adduced to illustrate any morbid change is preceded by a brief account of the symptoms that were observed, day by day, at the bed-side of the patient. For the sake of brevity however, no less than for that of clearness, none but the essential are noticed. The daily reports, of which all the cases cited, are exceedingly condensed forms, are full, and contain, as they necessarily must contain, many repetitions with which it would be worse than useless to burthen this account of them. Even the statement of the remedies that were adopted (excepting in as far as they obviously influenced the symptoms) is omitted, from the conviction that the mind cannot attend without distraction, at one and the same time, to the pathology and the treatment.
Predominance of affection is the principle according to which the cases are arranged, those in which the brain was most affected being classed together under one section—the cerebral; those in which the lungs were most affected under a second—the thoracic; and those in which the intestines were most affected under a third—the abdominal. In like manner, the individual cases under each section are so placed as to succeed each other, as nearly as possible, in the order of their severity.
Before entering into particular details, it may be useful to exhibit a brief outline of the general pathology of fever, shewing, at one view, the general results which are derived from an examination of the collective cases. In this outline the organs in each cavity are noticed in the order of the frequency and extent in which they are found diseased.