CHAPTER I.

OPERATION ON THE NECK.

The parts which we may wish to examine in the region of the neck in a post-mortem examination, include the tongue, the larynx, the trachea and the œsophagus. These may be removed together, by first making a single, straight incision from the chin, down the central line of the neck to the sternum. Next turn aside the integument with the superficial structures, separate the muscles of the tongue from their attachment to the jaw, and divide the mucous membrane of the floor of the mouth on either side of the tongue, when, with the tenaculum, the latter may be drawn down beneath the jaw. The neck being well extended and the tongue forcibly drawn down, the knife may be carried back on either side of that organ, dividing the muscles and mucous membranes, including the palatine arches and tonsils, when the tongue may be so drawn down as to permit the knife to reach the posterior walls of the pharynx. This being divided, from the slight adhesion to the spinal column, the whole may now be drawn down and removed together, the trachea and œsophagus being divided at the upper end of the sternum.

By the use of the enterotome, the pharynx, larynx and trachea may be laid open from behind, which will fully expose their interior for careful examination.

After the examination of the parts is completed, if it is desired to preserve the specimen, the cavity remaining may be so filled with paper or rags, as, upon the closing of the part, to leave little or no evidence of the absence of any portion.

Through the mouth, the buccal cavity may be examined, when there may be noted the condition of the teeth, gums, tonsils, palate, etc.; the presence or absence of ulcers on any of these parts, or of food or other foreign substances within the cavity.

OPERATION ON THE CHEST.

In opening the thoracic cavity for an examination of its contents, a straight incision may be made along the central line, through the skin and superficial tissues, from the upper end of the sternum, to near the umbilicus. If it is desired to examine the abdomen at the same time, the incision may be carried on to the pubis; otherwise, ending just above the umbilicus, a transverse cut may be carried from its lower end, to the border of the chest upon either side. These incisions being carefully carried through the muscles and peritoneum, the flap thus formed may be lifted and turned up upon the chest, and the peritoneum divided along the cartilages of the ribs. The integument with the pectoral muscles may now be dissected up together, and turned back as far as the union of the cartilages with the ends of the ribs. With the heavy cartilage knife, the former may now be divided near their union with the ribs; care being observed not to permit the knife to pass into the chest, and thus injure the lungs. In aged persons, and sometimes in the middle aged, the cartilages will be found so ossified, as to require the use of the saw or chisel in the place of the knife; this being more frequently required with the first ribs, than with any other. The ligaments uniting the clavicle with the sternum, having been divided, the latter may be removed by commencing at the lower end, and separating the diaphragm from its connections to the sternum and costal cartilages. The sternum being now lifted from below, the mediastinum may be divided, this forming the only bond of union to the parts beneath, except in cases, where, from pleuritic inflammation, adhesions may exist between the lungs and costal cartilages.

The sternum having thus been removed, the lungs will be found more or less collapsed from atmospheric pressure, unless adhesions be so extensive as to prevent.

The attention may now be given to the pericardium and heart. By making a small opening into the cavity of the former, any dropsical fluid present may be removed and measured. This may be accomplished, by introducing the point of a syringe into the opening, and carefully drawing the fluid into the same, and then forcing it into some vessel. Or, it may be carefully absorbed by a sponge, and then squeezed out and measured.

The _heart_ may be removed for examination, by dividing the large vessels springing from its base. In examining the cavities, valves, &c., the right auricles should first be opened, by an incision along its base, another meeting this at right angles, thus making two angular flaps, which may be turned aside, exposing the interior. In opening the ventricle, let one incision be made parallel with, and about one-third of an inch from the groove in the anterior surface dividing the right from the left ventricle, commencing at the base and extending to the apex; and another along the posterior groove, meeting the former at the apex, thus making a triangular flap, which may be lifted, exposing the interior of the cavity, without injury to the tendonous cords. The semilunar valves of the pulmonary artery may readily be exposed, by splitting open that vessel, and turning aside its walls. The left side of the heart may be examined in the same manner.

The examination of the _lungs_ may often be made _in situ_. Deep incisions may be made into their substance at various points, or portions may be removed for examination. If a more careful inspection is desired, or if we wish to examine the bronchial tubes or aorta, the whole thoracic viscera may be removed together. To accomplish this, divide the trachea and œsophagus, as they enter the chest, with also the branches arising from the arch of the aorta. Carry the hands around either lung, breaking up any adhesions which may be found, and then by grasping the trachea and arch of aorta, and dragging down upon the same, the posterior mediastinum may be divided from above downwards, the aorta and œsophagus divided as they pass the diaphragm, and the whole of the contents of the chest thus removed _en masse_. Placed upon a large tray, they may now be examined in detail. The bronchial tubes may be best inspected from behind, laying open the passages with the scissors at their posterior walls. By means of deep incisions, extending from apex to base upon the anterior surface, the condition of the interior of the organs may be carefully noted.

The examination completed, all blood should be sponged from the cavity, the organs replaced, and any remaining vacancy filled with bran or sawdust. The sternum now being placed in position, the incision may be sewed up.