Medical Jurisprudence, Forensic medicine and Toxicology. Vol. 1

by R. A. Witthaus; Tracy C. Becker

Superficial Examination of Thorax.—Observe the position, color, and degree of distention of the lungs. It should be remembered that healthy lungs, as soon as the chest is opened, owing to their inherent elasticity, will collapse, and when this normal collapse is not seen it is generally due to a loss of elasticity as occurs in emphysema, to inflammatory diseases binding the lung to the chest wall, or to the alveoli being filled with solid or fluid substances or pent-up air. Most complete distention is seen when death is due to drowning or suffocation.

The area of the heart uncovered will vary according to the degree of collapse of the lungs and to the abnormal size of the heart. Normally the cardiac area exposed is quadrangular in shape, and about three and a half inches in its longest diameter. Examine the pleural cavities for the presence of adhesions, foreign bodies, or fluid. If fluid is found it should be removed, measured, and its character noted. It is to be remembered that in warm weather, or when putrefaction has commenced, a moderate amount of reddish serum is found in the pleural cavities which has no pathological significance. Lastly, examine the mediastinum as to the condition of the thymus gland and great vessels outside the pericardium.

Pericardium.—Open the pericardium by an oblique incision along the anterior wall, and prolong this incision downward and outward toward the diaphragm and upward to its reflection from the great vessels. Normally, about a drachm of clear serum, sometimes, however, blood-stained from decomposition, will be found in the pericardial sac. The amount is best ascertained by raising the heart. Note next the contents of the pericardium and whether there is any serous, fibrous, or purulent exudation. If an abnormal amount of fluid is present, remove, measure, and note its character. Observe whether there are any adhesions between the two surfaces of the pericardium. White patches are often seen on the visceral surface of the pericardium, especially over the ventricles. These have no pathological significance and are due to slight thickenings of the pericardium.

The Heart.—Having passed the hand over the arch of the aorta and noticed whether there is any evidence of aneurism or dilatation, we grasp the heart firmly by the apex, raising and drawing it forward. We remove it by cutting through the vessels at its base. Test the sufficiency of the aortic and pulmonary valves by allowing a stream of water to flow into these vessels, the heart being held in a horizontal position and care being taken not to pull the valves open.

To apply the water test to the mitral and tricuspid valves, the auricles are first opened so as to expose the upper surface of these valves, and by allowing a stream of water to flow through the aortic and pulmonary valves into the cavities of the ventricles, the degree of sufficiency of these valves can readily be ascertained.

Another rough test is what is known as the “finger test.” The mitral valve will normally allow two fingers, held flat and in contact, to pass through its opening. The tricuspid in the same way allows, normally, three fingers to pass; or if a more accurate test of the degree of insufficiency is desired, the valvular orifices should be measured. Normally, the aortic orifice is one inch across; the mitral, one and eight-tenths inches; pulmonary, one and two-tenths inches; and the tricuspid about two inches.

We open first the cavity of the right ventricle by making an incision over its anterior border close to the septum. Prolonging the incision downward to the apex and upward through the pulmonary artery, the cavity of the ventricle will be fully exposed. The left ventricle is similarly opened by an incision through its anterior wall which is prolonged upward through the aortic valve. The cavities of the auricle and ventricle, especially those of the right side, will often contain blood-clots. These clots are usually post-mortem clots formed during the last hours of life or after death. It may sometimes be necessary to distinguish these post-mortem clots from what are known as ante-mortem clots. The latter are usually of firm consistency, dry, of a whitish color, and closely entangled in the trabeculæ, while the former are succulent, moist, of a reddish-yellow color, and are easily detached from the walls of the heart cavities. Ante-mortem clots are rarely seen, and the medical examiner should be careful not to attribute the cause of death to the post-mortem clots which are so often seen. After the heart is opened we can with more care and greater accuracy examine the condition of the valves and recognize the extent of valvular lesions.

The condition of the endocardium should now be examined and any abnormality noted. Often it will be seen stained a deep red color. This is not due to disease, but is caused by the absorption of the coloring matter of the blood which has been set free by decomposition. The size of the heart cavity and the thickness of the heart walls should be noted, as also their consistency and color. It should be remembered that the heart walls may appear unusually flabby as the result of decomposition, or apparently thickened when death occurs in extreme systole. The interior of the heart can be further examined by passing the enterotome into each auricle, carrying the incision through the mitral and tricuspid valves to join at the apex with the previous incision, which has been prolonged through the ventricles to the apex. Thus the auriculo-ventricular valves are completely exposed.