Loss of blood incompatible with life: Blood constitutes about 1/20 of the body weight of an adult. By volume, an average size adult has 5 to 6 quarts of blood (one quart is 946 cc). A loss of one tenth of its volume may not cause any significant clinical change. A loss of one quart may cause fainting even if the subject is lying down. But a loss of 1/3 to 2/5 of the circulating blood may result to irreversible hypovolemic shock and may be fatal. The volume of blood lost may be related to the rate or space of time a certain volume of blood has been shed. The blood loss may be massive but if it occurred for a long period of time, the hemopoietic organs may be able to replace it thereby preventing the development of any untoward effects. Males can stand more lost of blood than females. Hy- pertension may cause excessive and rapid bleeding from an arterial wound. Persons suffering from hemophilia and other clotting disorders and those being treated by anti- coagulants can cause prolonged bleeding. (2) Hemorrhage may result in ah increase in pressure in or on the vital organs to affect the normal function: Intracranial hemorrhage may cause compression of the vital centers of the brain. Hemopericardium (pericardial
MEDICO-LEGAL ASPECTS OF PHYSICAL INJURIES 279 tamponade) may cause embarrassment of the contraction of the heart. Hemorrhage into the chest cavity may cause diminution of the respiratory output with subsequent anoxia. (3) Hemorrhage may cause mechanical barriers to the function of organs: Hemorrhage into the tracheo-bronchial lumina can cause asphyxia. Interstitial hemorrhage into the muscles may cause disturbance in the contractility. b. Causes of Hemorrhage: (1) Trauma — Destruction of the blood vessel wall or increase permeability of its wall due to external force. (2) Natural Causes: (a) Common causes of hemorrhage due to natural causes: i. Intra-cerebral hemorrhage (apoplexy) : The most common blood vessel involved is the lenticulostraite branch of the middle cerebral artery with subsequent bleeding into the basal ganglia and adjacent structure. ii. Spontaneous subarachnoid hemorrhage : Usually due to rupture or perforation of a sac- cular berry aneurysm, commonly located at the bifurcation of one of the constituent vessels of the circle of Willis or one of its major branches. This is usually a congenital focal defect of the mus- cular layer with subsequent over stretching and degeneration of the internal elastic layer of the blood vessel wall. iii. Rupture of the arteriosclerotic aneurysm of the aorta: The weakening and thinning of the aortic wall may lead to fusiform or saccular aneurysm usually located at the abdominal portion. iv. Rupture of esophageal varices in cases of cirrhosis of the liver and bleeding of peptic ulcer of the stomach and duodenum.
- Fall '18
- Jane Blair
- Law, Evidence law