Hematoma

HEMATOMA, a tumor-like accumulation of blood that has escaped from blood vessels. The size of a hematoma depends on the pressure under which the blood escapes from the vessel and on the resistance offered by the surrounding tissues to the escaping blood. Blood escapes from vessels due to a) mechanical causes, which include damage to the integrity of vessel walls from contusion, fractures, puncture wounds (incised wounds), gunshot wounds, etc.; mechanical causes also include erosion of vessel walls by various pathological processes (most often tumors); b) due to disorders in the structure and function of blood vessel walls (various hemorrhagic diatheses, see). In the latter case, very slight external exposure may be sufficient for blood to escape from vessels and form a hematoma (sometimes, for example, in Werlhoff's disease, this occurs without any visible external exposure). Hematomas are often observed in surgical wounds and arise both from insufficiently thorough stopping of bleeding during surgery and from poor blood clotting, which depends on the underlying disease (hemophilia, cholemic bleeding, etc.). The blood in the hematoma cavity remains liquid for some time, then usually clots; the serum is absorbed through lymphatic spaces and then enters the general circulation of blood. The clot remains in the hematoma cavity; the erythrocytes enclosed in it disintegrate, the resulting blood pigment undergoes changes [hemosiderin (see), hematoidin (see Hemoglobin)]. The basis of the red blood cells, disintegrating, eventually undergoes resorption, as does the fibrin, breaking down into small particles. Phagocytes play a major role in the resorption of the disintegration products of the hematoma. Eventually, in the cavity of the former hematoma, blood pigment remains for a long time until it finally disappears (not always completely) from the tissue spaces. If the hematoma is located close to the skin, one can observe how the tumor-like formation becomes less tense, flattens, and at the same time, due to impregnation with dissolved blood pigment, the skin acquires a blue-purple color, which gradually changes to greenish, yellow. The reactive changes always present in the tissues surrounding the hematoma can reach a very significant degree in large accumulations. Around the extravasated blood, a dense capsule gradually forms. The formation of such a capsule slows down absorption, and the hematoma may turn into a cyst. The fibrin is partly replaced by connective tissue (organized). The liquid content, gradually losing pigment, eventually acquires the appearance of a weakly colored serum. With slow blood changes, another process can occur: as the blood escapes, it clots, the serum is absorbed, fibrin deposits continue to increase [see separate table (pp. 323-324), fig. 5]—a special fibrinous tumor forms, which can later be replaced by scar connective tissue. Suppuration often occurs as an outcome. Microorganisms can penetrate either through damaged skin adjacent to the hematoma or settle from the bloodstream. The latter is often observed in furuncles, phlegmons, and other purulent processes developing in the body simultaneously with the hematoma. In a number of cases, the source and routes of infection cannot be determined. - Treatment of hematomas should first be directed at the underlying cause (treatment, for example, of scurvy, see). Locally, especially with hematomas of mechanical origin, treatment should be expectant. With very great tension of tissues, severe pain, and no injury to a large blood vessel, sometimes the hematoma can be eliminated by puncture with aspiration of the contents. In blood cysts, as well as in rare cases of fibrin accumulation, it is necessary to resort to incision with removal of contents and tight closure. Suppurated hematomas require the same treatment as ordinary abscesses (see). Postoperative hematomas are opened by separating the edges of the wound and partial removal of sutures. (See also Bleeding). Haematoma subdurale (pachymeningitis interna haemorrhagica), an inflammatory membranous deposit on the inner surface of the dura mater, with interstitial hemorrhages. According to some authors, these hemorrhages are a primary phenomenon; only later, due to organization of the blood clot, connective tissue membranes are formed. According to others, first a pachymeningitis develops, forming a membrane rich in blood vessels. It is from these vessels that bleeding occurs. Thin membranes, numbering from 2 to 20, are superimposed on each other. On the inner surface of each membrane, numerous red and brown spots are observed, corresponding to small hemorrhages and accumulations of blood pigment. The youngest membrane faces the brain, while the oldest adheres to the dura mater. If the hemorrhage between individual membranes is more or less significant, then in this case we are dealing with a blood tumor—hematoma. The size of the tumor ranges from a small nut to a chicken egg. Subdural hematomas are more often found in the area of the parietal bones. - Etiology. It is observed, mainly, in people over 50 years of age. It is more often noted in chronic alcoholism, progressive paralysis, senile dementia, syphilis, especially hereditary. Subdural hematomas can be caused by scarlet fever, smallpox, typhus, tuberculosis, and other infections. In some cases, subdural hematomas may appear in marasmic children, in pernicious anemia, scurvy; more rarely, they are caused by injuries and inflammations spreading from neighboring organs. - Symptoms. Mild forms of the disease sometimes pass completely unnoticed. In severe cases, the disease develops apoplectiformly: the patient suddenly loses consciousness and falls into a comatose state lasting several hours or days. Temperature sometimes reaches 40°. All symptoms of the disease can be divided into general and local. General symptoms include: headache, disturbance of consciousness, slow or irregular pulse, vomiting, pupil constriction. Local signs are extremely diverse. With localization of the hematoma in the motor area, unilateral twitching and clonic convulsions most often occur, but hemi- and monoparesis are also observed. - Course of the disease. In severe cases, death quickly occurs; in milder cases, patients gradually recover, but after some time a new attack appears, indicating a new hemorrhage. After several such strokes, patients usually die. In rare cases, apparently, recovery is possible. - Recognition often presents considerable difficulties. Most often, it is necessary to exclude the following diseases: cerebral hemorrhage (with it, symptoms of brain irritation are rarely observed, and usually there is no increase in temperature in the first days), brain tumor (slow course of the disease, absence of fever), uremic coma (urine!). Red or dark yellow coloring of the cerebrospinal fluid speaks for subdural hematoma. - Treatment. Complete rest, ice on the head, local and even general bloodletting. Lumbar puncture often brings great benefit. If all these measures do not help, then trepanation of the skull and opening of the dura mater at the presumed site of the hematoma are resorted to.