If so, it must have caused death in one of the following ways:
1. Hemorrhage.—This may act by producing syncope. But the amount of the hemorrhage may not be sufficient for this result, and still cause death by disturbing the function of the organ into which it is effused, as in the brain or in the pleural or pericardial cavities. The blood here acts mechanically. Blood in the trachea may also kill mechanically by causing asphyxia.
The amount of hemorrhage required to produce syncope varies under a variety of circumstances. Less is required in the very young, the aged, and the diseased, also less in women than in men. Young infants may die from hemorrhage from very slight wounds, even from the application of a leech or the lancing of the gums. A sudden loss of blood is much more serious than an equal amount lost slowly. This is the reason that the wound of an artery is more serious and more rapidly fatal than a similar loss of blood from other sources. It is hard to specify the absolute quantity which must be lost in order to cause death by syncope. The total blood in the body is about one-thirteenth of the weight of the body, making the total amount of blood weigh about twelve pounds. Of this, about one-fourth is in the heart, lungs, and large blood-vessels. According to Watson, the loss of an amount varying from five to eight pounds is enough to be fatal to an adult. But less is enough to prove fatal in many cases, as the rapidity of the loss of blood and the age, sex, and bodily condition of the wounded person affect the amount necessary. Though death from a small artery is slower than that from a large one, yet it may occur in time, as shown in the instance quoted by Taylor,[626] where a man bled to death in thirty-eight hours from the wound of an intercostal artery. Thus, too, a wound of the branches of the external carotid artery is often enough to cause death, and a wound in a vascular part may cause death from hemorrhage, though no vessel of any size be divided.
Internal hemorrhage may be fatal from mechanical interference with the function of an organ, as well as from syncope. Thus we may have death from syncope due to hemorrhage into the peritoneal cavity or, after contusions, into the intercellular spaces and the cavity due to the blow, into which several pounds of blood may be extravasated. Internal hemorrhage is most fatal when due to the rupture of a viscus such as the heart, lungs, liver, kidney. Taylor[627] cites a case of a man run over and brought to Guy’s Hospital in November, 1864. He had pain in the back, but there were no symptoms or marks of severe injury. He left the hospital and walked home, where he was found dead in bed a few hours later. His abdomen contained a large amount of blood from the rupture of a kidney. After severe flagellation blood may be effused in large quantity beneath the skin and between the muscles, which is just as fatal as if it had flowed externally from a wound. In fact, if the injuries are numerous the loss of much less blood is enough to prove fatal, the element of shock here assisting that of hemorrhage.
How are we to ascertain whether a person has died from hemorrhage? This may be more difficult in the case of an open wound, for the body may have been moved from the spot where it lay after the wound was received, and the blood on the body, clothes, and surrounding objects may have been removed. Then the case may be presumptive only, but we may arrive at a definite conclusion by attention to the following points: If the wound was in a very vascular part and of some size, or if a large vessel or many moderately large vessels were divided and the vessels, especially the veins in the neighborhood, are empty, then we may be quite sure of death from hemorrhage. If there is no disease found which could be rapidly fatal the case is still stronger. The body should be pallid after fatal hemorrhage, but the same may be the case from death from other causes. In case the body and surrounding objects have not been disturbed, then the amount of clotted blood in the wound, on the body and clothes, and about the body, taken in connection with the foregoing points, can leave no doubt. We should remember, however, that not all the blood about the body was necessarily effused during life, but a little hemorrhage may have occurred after death while the body was still warm and the blood fluid, i.e., during the first four, eight, or ten hours. But the amount thus lost is small. In cases of death from internal hemorrhage we do not have so much difficulty in pronouncing an opinion, as by post-mortem examination we can determine the amount of the hemorrhage. We can judge, too, from its position, whether it has acted mechanically to interfere with a vital function, and has thus caused death, or whether the latter was due to syncope from the quantity lost.
2. Severe mechanical injury of a vital organ, such as crushing of the heart, lungs, brain, etc. This crushing may be accompanied by hemorrhage, but death may be more immediate than the hemorrhage would account for. The mechanical injury done to the vital centres in the medulla by the act of pithing is the direct cause of the sudden death which follows it. Exceptionally slight violence to a vital organ is fatal, but this may be better explained by attributing it to shock.
3. Shock.—An injury is often apparently not enough to account for the fatal result so speedily. The marks of external injury may fail entirely or be very trifling. Thus more than once persons have died in railway collisions with no external marks of violence. So, too, a blow on the upper abdomen, on the “pit of the stomach,” has been rapidly fatal without any visible injury to the viscera. Death is attributed to the effect on the cardiac plexus, and there may be no marks externally or only very superficial ones. In Reg. v. Slane and Others (Durham Wint. Ass., 1872), quoted by Taylor,[628] the deceased was proved to have sustained severe injuries to the abdomen by kicks, etc., but there were no marks of bruises. All organs were found healthy on post-mortem examination, but the injured man died in twenty minutes. Death was attributed to shock and the prisoners were convicted of murder.
Death from concussion of the brain is another example of death from shock. This may occur with only a bruise on the scalp and with no intracranial hemorrhage or laceration of the brain. The medical witness should be cautious in the above classes of cases in giving evidence, as the defence may rely upon the absence of any visible signs of mortal injury to prove that no injury was done, a principle fundamentally wrong.
Also a number of injuries, no one of which alone could be the direct cause of death, may cause death on the spot or very soon afterward. Death in such cases, where there is no large effusion under the skin, is referred to exhaustion, which, however, is merely another term for shock. Such cases are exemplified by prize-fighters who, during or after the fight, become collapsed and die of exhaustion. Having sustained numerous blows on the body during the many rounds, the body presents the marks of various bruises, but there may be nothing else to explain the sudden death. No one injury or bruise is mortal, and yet, when the deceased was previously sound and in good health, death must be referred directly to the multiple injuries received in the fight. We have already stated above that if the injuries are numerous, the loss of a smaller amount of blood may be fatal. We see, therefore, that there is not always a specific and visible “mortal” injury to account for death. This is a well-known medical fact, but it does not accord with the erroneous popular prejudice that no one can die from violence without some one visible wound which is mortal. In other words, the non-professional mind leaves out of account the idea of shock, only regarding material injury and not functional disturbance. If the circumstances accompanying death are unknown, it is well to be cautious. But if the deceased was in ordinary health and vigor and there was no morbid cause to account for the sudden death, we need not hesitate to refer death to the multiple injuries.