Manual of Surgery by Alexis Thomson (book recommendations for young adults .TXT) 📖

Wounds of the Thoracic Duct.—The thoracic duct usually opens at the angle formed by the junction of the left internal jugular and subclavian veins, but it may open into either of these vessels by one or by several channels, or the duct may be double throughout its course. There is a smaller duct on the right side—the right lymphatic duct. The duct or ducts may be displaced by a tumour or a mass of enlarged glands, and may be accidentally wounded in dissections at the root of the neck; jets of milky fluid—chyle—may at once escape from it. The jets are rhythmical and coincide with expiration. The injury may, however, not be observed at the time of operation, but later through the dressings being soaked with chyle—chylorrhœa. If the wound involves the only existing main duct and all the chyle escapes, the patient suffers from intense thirst, emaciation, and weakness, and may die of inanition; but if, as is usually the case, only one of several collateral channels is implicated, the loss of chyle may be of little moment, as the discharge usually ceases. If the wound heals so that the chyle is prevented from escaping, a fluctuating swelling may form beneath the scar; in course of time it gradually disappears.

An attempt should be made to close the wound in the duct by means of a fine suture; failing this, the duct must be occluded by a ligature as if it were a bleeding artery. The tissues are then stitched over it and the skin wound accurately closed, so as to obtain primary union, firm pressure being applied by dressings and an elastic webbing bandage. Even if the main duct is obliterated, a collateral circulation is usually established. A wound of the right lymphatic duct is of less importance.

Subcutaneous rupture of the thoracic duct may result from a crush of the thorax. The chyle escapes and accumulates in the cellular tissue of the posterior mediastinum, behind the peritoneum, in the pleural cavity (chylo-thorax), or in the peritoneal cavity (chylous ascites). There are physical signs of fluid in one or other of these situations, but, as a rule, the nature of the lesion is only recognised when chyle is withdrawn by the exploring needle.

Lymphangitis.—Inflammation of peripheral lymph vessels usually results from some primary source of pyogenic infection in the skin. This may be a wound or a purulent blister, and the streptococcus pyogenes is the organism most frequently present. Septic lymphangitis is commonly met with in those who, from the nature of their occupation, handle infective material. A gonococcal form has been observed in those suffering from gonorrhœa.

The inflammation affects chiefly the walls of the vessels, and is attended with clotting of the lymph. There is also some degree of inflammation of the surrounding cellular tissue—peri-lymphangitis. One or more abscesses may form along the course of the vessels, or a spreading cellulitis may supervene.

The clinical features resemble those of other pyogenic infections, and there are wavy red lines running from the source of infection towards the nearest lymph glands. These correspond to the inflamed vessels, and are the seat of burning pain and tenderness. The associated glands are enlarged and painful. In severe cases the symptoms merge into those of septicæmia. When the deep lymph vessels alone are involved, the superficial red lines are absent, but the limb becomes greatly swollen and pits on pressure.

In cases of extensive lymphangitis, especially when there are repeated attacks, the vessels are obliterated by the formation of new connective tissue and a persistent solid œdema results, culminating in one form of elephantiasis.

Treatment.—The primary source of infection is dealt with on the usual lines. If the lymphangitis affects an extremity, Bier's elastic bandage is applied, and if suppuration occurs, the pus is let out through one or more small incisions; in other parts of the body Klapp's suction bells are employed. An autogenous vaccine may be prepared and injected. When the condition has subsided, the limb is massaged and evenly bandaged to promote the disappearance of œdema.

Tuberculous Lymphangitis.—Although lymph vessels play an important rôle in the spread of tuberculosis, the clinical recognition of the disease in them is exceptional. The infection spreads upwards along the superficial lymphatics, which become nodularly thickened; at one or more points, larger, peri-lymphangitic nodules may form and break down into abscesses and ulcers; the nearest group of glands become infected at an early stage. When the disease is widely distributed throughout the lymphatics of the limb, it becomes swollen and hard—a condition illustrated by lupus elephantiasis.

Syphilitic lymphangitis is observed in cases of primary syphilis, in which the vessels of the dorsum of the penis can be felt as indurated cords.

In addition to acting as channels for the conveyance of bacterial infection, lymph vessels frequently convey the cells of malignant tumours, and especially cancer, from the seat of the primary disease to the nearest lymph glands, and they may themselves become the seat of cancerous growth forming nodular cords. The permeation of cancer by way of the lymphatics, described by Sampson Handley, has already been referred to.

Lymphangiectasis is a dilated or varicose condition of lymph vessels. It is met with as a congenital affection in the tongue and lips, or it may be acquired as the result of any condition which is attended with extensive obliteration or blocking of the main lymph trunks. An interesting type of lymphangiectasis is that which results from the presence of the filaria Bancrofti in the vessels, and is observed chiefly in the groin, spermatic cord, and scrotum of persons who have lived in the tropics.

Filarial disease in the lymphatics of the groin appears as a soft, doughy swelling, varying in size from a walnut to a cocoa-nut; it may partly disappear on pressure and when the patient lies down.

The patient gives a history of feverish attacks of the nature of lymphangitis during which the swelling becomes painful and tender. These attacks may show a remarkable periodicity, and each may be followed by an increase in the size of the swelling, which may extend along the inguinal canal into the abdomen, or down the spermatic cord into the scrotum. On dissection, the swelling is found to be made up of dilated, tortuous, and thickened lymph vessels in which the parent worm is sometimes found, and of greatly enlarged lymph glands which have undergone fibrosis, with giant-cell formation and eosinophile aggregations. The fluid in the dilated vessels is either clear or turbid, in the latter case resembling chyle. The affection is frequently bilateral, and may be associated with lymph scrotum, with elephantiasis, and with chyluria.

The diagnosis is to be made from such other swellings in the groin as hernia, lipoma, or cystic pouching of the great saphenous vein. It is confirmed by finding the recently dead or dying worms in the inflamed lymph glands.

Treatment.—When the disease is limited to the groin or scrotum, excision may bring about a permanent cure, but it may result in the formation of lymphatic sinuses and only afford temporary relief.

Lymphangioma.—A lymphangioma is a swelling composed of a series of cavities and channels filled with lymph and freely communicating with one another. The cavities result either from the new formation of lymph spaces or vessels, or from the dilatation of those which already exist; their walls are composed of fibro-areolar tissue lined by endothelium and strengthened by non-striped muscle. They are rarely provided with a definite capsule, and frequently send prolongations of their substance between and into muscles and other structures in their vicinity. They are of congenital origin and usually make their appearance at or shortly after birth. When the tumour is made up of a meshwork of caverns and channels, it is called a cavernous lymphangioma; when it is composed of one or more cysts, it is called a cystic lymphangioma. It is probable that the cysts are derived from the caverns by breaking down and absorption of the intervening septa, as transition forms between the cavernous and cystic varieties are sometimes met with.

The cavernous lymphangioma appears as an ill-defined, soft swelling, presenting many of the characters of a subcutaneous hæmangioma, but it is not capable of being emptied by pressure, it does not become tense when the blood pressure is raised, as in crying, and if the tumour is punctured, it yields lymph instead of blood. It also resembles a lipoma, especially the congenital variety which grows from the periosteum, and the differential diagnosis between these is rarely completed until the swelling is punctured or explored by operation. If treatment is called for, it is carried out on the same lines as for hæmangioma, by means of electrolysis, igni-puncture, or excision. Complete excision is rarely possible because of the want of definition and encapsulation, but it is not necessary for cure, as the parts that remain undergo cicatrisation.