Text book of veterinary medicine, Volume 1 (of 5)

by James Law

PHLEBITIS.

Divisions, traumatic and idiopathic. Causes, punctures, defective blood supply in walls, debile coats, thrombus, infection, overstretching, injury or disease of serosa, irritants in blood, microbic infection. Lesions, exudation, cell growth, breaches in serosa. Adhesive phlebitis, desquamation, granulation, occlusion. Suppurative phlebitis, infection, pyæmia, erysipelas, metritis, ulceration, neoplasms, phlebolites. Symptoms, local, firm, corded, swollen vein, extends entad, venous congestion, dropsy, gangrene, diagnosis from lymphangitis. Fever, venous congestion in vicinity. Treatment, germicide, rest, cold, antiseptics, blisters.

Inflammation of veins as seen in the lower animals has usually been a sequel of bleeding and is hence a purely surgical lesion. Animals as well as man however are subject to idiopathic phlebitis which as affecting the deeper seated veins may be held to be a medical subject.

The causes of idiopathic phlebitis are varied. Injury to the walls like the punctures made in bleeding; if they result in the exposure of a raw, and above all an inflamed, surface to the blood, tends to the formation of a thrombus, and of local inflammation. Even the inflammation of the outer coat tends in the same way to thrombosis and phlebitis, and the experiment of Nicasse showed that the dissection of its sheath from a vein, thus robbing it of its vascular and nervous supply promptly induced coagulation of the blood in the denuded part. The debilitated or devitalized walls evidently give off fibrinogen and fibrine ferment in amount that is incompatible with the maintenance of fluidity. All other forms of direct injury to the veins, leading to disturbance of the endothelium or cell enlargement or exudation in the intima, will operate in the same manner. Sometimes as in puerperal phlebitis the inflammation extending from the adjacent tissue to the walls of the veins, determines thrombosis, and the invasion by pus microbes determines suppuration. Bruises, overstretching, pressure with overdistension, and the circulation in the blood of irritant matters may lead to changes in the wall, thrombus, and inflammation. Such irritants may be septic or other bacterial products, or they may arise from the colonization of bacteria on or in the venous coats with the same final result.

The lesions in the vein are often primarily of the nature of exudation and cell growth in the coat, without at first any change in the serosa or endothelium. Later the changes implicate those, thrombosis follows and one of various ulterior processes.

In adhesive phlebitis which is most frequent as the result of purely mechanical injury, the endothelium is desquamated and granulations from the denuded surface extend into the clot and finally occlude the vein. A recovery takes place by the organization of this new product and the contraction of the vessel into a simple fibrous cord.

In suppurative phlebitis, which occurs especially in connection with infection (erysipelas, metritis), the inflammation, though starting in the same way in the vascular coats, advances rapidly to suppuration, and the intima, lying in contact with the resulting thrombus may become itself the seat of the suppurating process. Cases of this kind are almost of necessity in the nature of an infection and the danger is greatly enhanced. Small abscesses formed in the vascular coats may burst into the vein and passing on with the blood produce general infection (pyæmia). Even when the pus enters the vein at a point covered by the thrombus, it may escape by the partial loosening of the clot from the serosa, or through the interior of a honey-combed coagulum and thus lead to general infection. This is especially liable to follow in erysipelas and metritis, in which the tendency as in the solid tissues is to diffuse suppuration without any investing limiting membrane. There are other forms of bacterial colonization of the vascular walls, of ulceration, and of the extension of morbid growths into or through the venous walls, producing inflammation more or less localized, and leading or not to general infection. The presence of phlebolites in the vein is a conceivable source of phlebitis, though no such case has been so far recorded.

The symptoms in localized cases of simple adhesive phlebitis may be purely local. The vein if within reach may be felt like a firm, rounded cord, which extends in a direction from the heart. If there are no free anastomosis with neighboring veins on the distal side of the thrombus, venous congestion and dropsy of the tissues ensue, and in some cases moist gangrene. When, however, such anastomosis is abundant these peripheral symptoms may be absent, especially if the affected vein returns blood from a higher level than the heart, and then the symptoms are confined to the vein and its immediate surroundings. From lymphangitis which shows similar hard cords, it is distinguished by the absence of an extended network of diseased vessels, by the lack of a diffuse, doughy swelling, and by the fact that the adjacent lymph glands remain free from inflammation, pain and swelling. In the more extended cases there is fever, which may be of a very high type and may merge into pyæmia. In deep-seated cases it may be difficult to identify the disease, but it may be suspected if in the course of erysipelas or metritis there is a sudden increase of fever with pain and swelling, and distension of veins leading into the part.

The treatment of idiopathic phlebitis is largely that of the particular infecting disease on which it depends. In simple cases due to trauma absolute rest and the application of ice and antiseptic solutions, or where these cannot be applied, the use of antiseptics internally, will be indicated. Hyposulphite of soda and sulphide of calcium are especially indicated. From the early days of veterinary medicine, flying blisters of Spanish flies, over the inflamed vein or veins have proved very successful, and under the lead of Nonat the same was in 1858 and since adopted with gratifying success in the human subject. Abscesses formed in accessible situations should be promptly opened and treated antiseptically, and swelling of the affected part should be checked by elevated position, or if that is impossible, by a smoothly applied bandage. Rubbing and active movement are dangerous, as tending to detach clots which float off to start new emboli and inflammations in the lungs.