The purpose primarily of post-mortems is to determine the cause of death. Frequently there are found several diseased organs. The question then arises as to the order in which they were involved and from what their condition resulted.

The examination may be divided into the inspection of the external appearances and into the examination, both macroscopic and microscopic, of the internal organs.

During the post-mortem there should be some one to take notes on the various findings. If possible, the clinical history of the case should be learned before the autopsy is begun.

External Inspection

The appearances should be carefully noticed, as they are of great importance, particularly in medico-legal cases, such as approximate age; sex; height, measured as the body lies on its back between two uprights; bodily development; condition of nutrition; general condition of the skin; amount of fat present.

Distinguishing marks; irregularities of the teeth, deformities of any kind; fractures; wounds, whether ante-mortem or postmortem. If the former, there may be indications of bleeding, edges will gape, and there will be some signs of inflammation or beginning repair. If post-mortem injury, there will be no escape of blood into the tissues, no bleeding on incision, no inflammation or repair.

Presence of edema, most common in the lower extremities at the ankles, the scrotum, and labia.

Signs of decomposition, first appearing as a greenish discoloration of the abdomen and prominence of the superficial veins due to the staining of the tissues by blood-pigment from degenerated erythrocytes.

Rigor mortis, its degree and extent; post-mortem lividity, or hypostases, is present in dependent parts and disappears on pressure; diffuse pigmentation, the result of decomposition, does not disappear on pressure.

The condition of the pupils, whether dilated, contracted or unequal; the sclera; size and shape of thorax; distention or retraction of abdomen.

Internal Inspection

The generally accepted order of examination is brain, spinal cord, thorax, and abdomen. The brain should be examined first, so that the amount of blood in the cerebral vessels can be determined. As in this country autopsies are usually limited to the thorax and abdomen, they will be first described.

The autopsy should not be done by artificial light, as the color values are distorted.

The operator should stand on the right side of the body and should grasp the handle of the knife as he would in cutting bread. The knife should be drawn and not pressed or shoved into the tissues. The main movement should come from the shoulder, the secondary from the elbow-joint.

Incisions into organs should be deep and single rather than shallow and numerous, as a broad surface gives much more information than a narrow one.

The primary incision is a long single one extending from the larynx along the median line to the pubes, passing to the left of the umbilicus so as to avoid the round ligament of the liver. The knife should be held almost horizontal so that the belly and not the point is used. .

Over the sternum the incision extends to the bone; over the abdomen it should go only as deep as the subcutaneous tissue or the muscle. The abdominal cavity is opened by making a small incision through the peritoneum a little below the xiphoid cartilage. Two fingers of the left hand are inserted, the flaps drawn upward, and the incision continued between them down to the pubes. The recti muscles may be divided just above the pubes, care being taken not to cut the skin.

The abdominal flaps in turn are seized with the left hand and strongly drawn outward. This renders the tissues tense and they are dissected away from the ribs by long sweeping cuts. The operation begins over the lower border of the ribs and is carried up a little above the articulation of the clavicle and outward as far as the anterior axillary line.

The abdomen should then be inspected, first without touching anything. The organs and their relations should be noted; the character and the amount of any fluid present and any that runs off should be caught and measured. The omentum should be removed and the intestines examined, also the appendix and the mesenteric lymph-nodes. The peritoneum normally is smooth, glistening, and transparent, the same as any serous membrane.

The height of the diaphragm is determined by introducing the hand under the costal margin and finding at what rib or interspace the muscle reaches in the mid-clavicular line. On the right side it is usually about the level of the fourth rib or interspace, on the left is about the third rib or interspace. If the diagram is lower than normal it generally indicates fluid in the pleural cavity, enlargement of the thoracic organs or new growths.

Before opening the thoracic cavity, if pneumothorax be suspected raise the skin flap and fill the pocket thus formed with water. Puncture below the level of the water and watch for bubbles to come through.

The thorax is opened by cutting through the costal cartilages, from the second down, by holding the knife almost horizontal and resting it on the rib in advance before the previous one is completely severed. The division should take place at the junction of the rib and cartilage. Instead of using a knife the intercostal spaces may be first opened and the ribs then divided by means of the costotome. By this method there is less danger of cutting into the lungs.

The sternum is elevated by grasping the xiphoid cartilage; the attachment of the diaphragm is divided on either side. It is freed from the underlying tissues by long cuts of the knife, which should be made close to the bone so as to avoid the pericardium. When the first rib is reached its cartilage is divided about 2 cm. further out than that of the second. The edge of the knife should be directed upward and outward, the handle being beneath the elevated sternum.

The clavicle may be disarticulated by cutting from below along the irregular line of the sterno-clavicular articulation. By this method there is less danger of wounding the large vessels at the base of the neck, a very important point in medico-legal cases. The articulation may be divided from above by entering a narrow knife along the line of the joint, which curves down and out. The handle of the knife should incline so that it is nearer the cadaver's chin than is the blade. If held perpendicular both the clavicle and sternum interfere, as the joint slants. If properly carried out, it can be done without any great force being exerted, short up and down strokes being used. The sternum should then be twisted out rather than cut, otherwise the large vessels of the neck may be divided.

If the cartilages have become calcified, care should be taken not to cut one's hands on the exposed ends. Protection can be had by drawing the dissected flap of skin over the edges.

If removal of the sternum is not allowed, the thoracic organs may be removed from below by separating the diaphragm from the ribs.

On removal of the sternum, the lungs and the pericardial sac are exposed. One should notice how near the lungs come to meeting in the median line. Ordinarily they will touch at the level of the second rib.

The pleural cavities should be examined. One should determine the presence or absence of fluid, its character and amount. Adhesions should be looked for, and the amount of force required to break through them is a guide as to their duration. If the adhesions are very dense, the best way when one comes to remove the lungs is to strip off the costal layer of the pleura with the viscera.

In opening the pericardium the sac is picked up by the fingers and an incision made upward to where the large vessels enter at the base of the heart. This cut is continued 17 downward to the lower right border. From the middle of this incision one is made down to the apex. The cut should be made from within out, so as to avoid wounding the heart.

By lifting up the apex of the heart the amount and character of the contained fluid can be determined. Is usually only 5 to 10 c.c.

The presence or absence of adhesions between the heart and pericardium should be noted. Sometimes the entire cavity may be obliterated.

Before making any incisions into the heart, its size, shape, and position should be noted. The distention or contraction of the various cavities should be determined.