A system of practical medicine. By American authors. Vol. 1

by Unknown

Having carefully examined the terms employed by various authors in connection with the morbid changes which are known to occur in certain cases of septic contamination, we give our preference to the following nomenclature: Septicæmia, septo-pyæmia, pyæmia simplex, and pyæmia multiplex.

The term septo-pyæmia is applied to a morbid condition possessing certain peculiarities of both septicæmia and pyæmia, and it is supposed to arise from the absorption of both poisons; the term pyæmia simplex is applied to a pyæmic condition in which there is no metastasis; while the name pyæmia multiplex is given to that form of disease which is characterized by the existence of metastatic abscesses. It may be well to add here that this nomenclature is not intended to cover all cases of septic poisoning, but to be applied to those cases only in which the morbid changes give to the terms a certain degree of appropriateness.

Septic poisoning may be justly regarded as a single chain composed of many links. Take, for example, a case of amputation of the thigh, followed within a few hours by traumatic fever, later by septicæmia; afterward there may be developed secondary fever; formation of ichorous pus, with absorption and its concomitants; pyæmia, accompanied by embolism, thrombosis, abscess in the lungs, liver, etc. To these may also occasionally be added phlebitis and inflammation of the joints, terminating speedily in suppuration. This chain may in this case be further lengthened or varied with traumatic erysipelas or with hospital gangrene. In fact, the variations in these cases are very numerous, and all these conditions, together with many others, are due to septic blood-poisoning.

ETIOLOGY OF PYÆMIA.—Four theories have been advanced at different times to explain the etiology of pyæmia, and they have been designated as follows: the mechanical, the nervous, the chemical, and the germ theories respectively; and their action is based on the following hypotheses: 1, that pus enters the blood, circulates in it, and acts as a poison; 2, that an irritation is excited in certain visceral organs in sympathy with inflammation of the fibrous membranes of the cranium or the bones of the upper or lower extremity, and there is thus produced a metastasis to these organs of an ichorous miasm or of a fluid which is more or less acrid; 3, that a chemical poison is generated from the pus in the wound, and when it is absorbed produces pyæmic manifestations; 4, that the putrefaction of pus in wounds is caused by a microscopic organism which enters the circulation and produces pyæmia.

The first hypothesis was somewhat modified, as we have already mentioned, by John Hunter and others, who advanced the idea that pyæmia consisted essentially of a phlebitis, and that the pus found in the circulation had its origin within the veins. However, it has since been shown conclusively that pyæmia cannot be produced by the injection of healthy pus into the cellular tissue or veins. This fact having been generally admitted by the profession, it is thought unnecessary to adduce here either the experiments or the arguments which have been accepted as conclusive on this important point. It is not even necessary to bring forward the disputed question of the possibility of the entrance of pus into the blood, since laudable pus does not produce pyæmia. In fact, we have reached a point in the progress of medicine when the discussion of either the first or second hypothesis ceases to be interesting to medical men. Consequently, our chief interest in the study of the etiology of pyæmia centres in the third and fourth hypotheses; and we believe that it may be safely asserted that the origin of this disease has been fully demonstrated by an almost unlimited number of experiments.

The injection of pus into living animals produces local, remote, and constitutional symptoms. The character of these symptoms depends principally on the kind of pus, laudable or ichorous, the quantity injected, and the site of the injection. It will be readily perceived that in cases where the pus is thrown directly into a vein the local symptoms would be unimportant, while the danger of remote trouble—metastatic abscesses in the lungs, liver, etc.—would be very great; but should the injection be made into the connective tissue, then the relations would be reversed. Constitutional symptoms may exist in both cases, but will differ in character and degree.

In regard to the character of the pus, and its agency in the production of this disease, Billroth says: "The old view, that pyæmia is only induced when decomposed pus (ichor) is reabsorbed, is entirely erroneous. There are cases where decomposed, putrid pus enters the blood, and which present a combination of the symptoms of septicæmia and pyæmia (septo-pyæmia of Hueter)."²⁵ Dupuytren failed to produce metastasis by injections of pus into the veins of dogs; these results were confirmed by Boyer, who only obtained metastasis when he used ichorous pus in his experiments. The same results are recorded in the works of Günther and Sedillot, based on numerous experiments. Beck made fourteen experiments very carefully, but did not succeed in producing metastasis in a single case. The same results are recorded by a commission of the Physiological Society of Edinburgh. O. Weber has recently shown by extended experiments that carefully filtered pus will not produce metastatic abscesses in the lungs. Therefore, it may be considered as proved that fluid pus injected into the veins of an animal produces no metastatic points of inflammation.

²⁵ Surgical Pathology, p. 344.

It should not be supposed, however, that because injection of fresh (non-ichorous) pus failed to produce metastatic abscesses, it was therefore without results, as the earlier experimenters thought. Billroth and O. Weber have shown by their recent experiments that these injections are uniformly followed by fever, and, if subcutaneous, by abscess; and further, that injections of fresh pus produce even a higher temperature than do those of ichorous pus; but the pus taken from cold abscesses has apparently very slight effect. The fresh non-ichorous dried pus was found to possess in a similar degree the power to excite inflammation and suppuration; even the removal of the albumen did not change its character or power. It will be observed that these injections caused not only local inflammations, but severe constitutional symptoms, as high temperature, etc. Experiments have thus far completely failed to show the agent that excites the inflammation, although it is generally admitted that it at least exists in the molecular bodies.

Virchow and Panum have shown conclusively by their experiments on living animals that the introduction of foreign bodies into the veins—as powdered coal, wax balls, and quicksilver—fail in all cases to produce metastatic abscesses in the visceral organs or symptoms of pyæmia. These foreign bodies were frequently found blocking up the terminal branches of the pulmonary artery, in some cases encapsulated, frequently resembling miliary tubercles, and occasionally surrounded by evidences of slight local inflammation, but in every instance without suppuration. The same experimenters, however, observed that the introduction of ichorous pus and decomposing animal tissue into the veins was attended with the formation of metastatic abscesses and other symptoms of pyæmia. They therefore conclude that the introduction of putrid animal substances into the veins, and the further transport of the same to the branches of the pulmonary artery, produce metastatic abscesses, and that the origin of these deposits is independent of the mere stopping up of the branches of this artery.