The state of the blood in this disease is one of peculiar interest, dominating as it does its whole pathology and determining its nosological position. It is the blood of a phlegmasia rather than of a pyrexia. This fact was early established by American physicians who observed the disease, and the opportunities for doing so were not wanting, since venesection was used by every one who treated it. In 1807-09 a rapidly fatal case or two was found in which the "blood was darker and had a larger proportion of serum than usual," but in others "it did not present any uncommon appearance, and no inflammatory buff, nor was it dissolved" (Fish). In 1811, Arnell stated that "the blood drawn in the early stage appeared like that of a person in full health; there was no unusual buffy coat, neither was the crassamentum broken down or destroyed." In the epidemic studied by Mannkopff (1866) he found that blood obtained by venesection gave a clot with a thick buffy coat. Andral, seeking to establish the law that in every acute inflammation there is an increase in the fibrin of the blood, remarks that in a case of cerebro-spinal meningitis it was very marked.53 Ames states that "the blood taken from the arm and by cups from the back of the neck" "coagulated with great rapidity." "Its color was generally bright—in a few cases nearly approaching to that of arterial blood; it was seldom buffed; in thirty-seven cases in which its appearance was noted it was buffed in only four." Analyses were made in four cases, "the blood being taken early in the disease from the arm, and was the first bleeding in each case. They furnished the following results:
| Fibrin. | Corpuscles. | |
| I | 6.40 | 140.29 |
| II | 5.20 | 112.79 |
| III | 3.64 | 123.45 |
| IV | 4.56 | 129.50 |
The first was from a laboring man thirty-five years old; the second from a boy twelve years old, while comatose; and the two others from stout women between thirty and thirty-five."54 Tourdes, whose analyses follow, states that "blood drawn from a vein was rarely buffed; if a buffy coat existed, it was thin, and generally a mere iridization upon the surface of the clot."55
| Fibrin. | Corpuscles. | |
| I | 4.60 | 134.00 |
| II | 3.90 | 135.54 |
| III | 3.70 | 143.00 |
| IV | 5.63 | 137.84 |
Maillot gives, as the result of an analysis of six cases, an increase of fibrin to six parts and more in a thousand. This summary represents, as far as is known, all of the analyses of blood taken from living patients in this disease, and it shows that in every case the proportion of fibrin exceeded that of healthy blood, and corresponded exactly to that observed in the blood of inflammatory diseases, while the proportion of red corpuscles varied within the normal limits. How different is this condition of the blood from that of typhus fever, in which there is a marked diminution of fibrin, and a falling off in the red corpuscles as well, or from that of typhoid fever, in which neither element declines until the disease affects the body by inanition! (Murchison).
53 Path. Hæmatology, p. 73.
54 New Orleans Med. and Surg. Jour., Nov., 1848.
55 Epidemie de Strasbourg, p. 160.
In regard to the condition of the blood after death the historians of the disease are not so well agreed; nevertheless, the preponderance of the testimony is in favor of the statement that the blood presents appearances resembling those belonging to the continued fevers rather than to the inflammations. It is true that even in this the agreement is neither general nor complete. Tourdes, for example, states that in an autopsy "the blood was remarkable for the abundance and toughness of the fibrinous clots," but the greater number have reported it as being dark and liquid. Such was its condition in the epidemic which we studied at the Philadelphia Hospital in 1866-67, and it has been correctly described by Dr. Githens as follows: "The blood was fluid, of the color and appearance of port-wine lees; under the microscope the corpuscles were shrivelled and crenated, and there was a space apparent between them as they were arranged in rouleaux. There were in two cases white, firm, fibrinous heart-clots extending through both ventricles and auricles and into the vessels leading to and from the heart."56 It may be added that the red corpuscles are often crenated and shrivelled when the case has been protracted, and it has been stated—from limited observation, indeed—that "the white corpuscles are three times more numerous than the red."57 The blood has been scrutinized to discover, if possible, some of those bodies which are judged by Koch and his disciples to differentiate general diseases, but it is stated that the investigation has been without definite result.58