Strangulation is almost always homicidal, hanging almost always suicidal, and suffocation (limited) usually accidental, but also often homicidal.
Strangulation may be admitted, therefore, as including all cases of suffocation by pressure on the neck, whether by cords or the hand; but excluding hanging.
It will facilitate the study of the subject if we use the word ligature as a general term to cover the many forms of cords, ropes, etc., used in strangulation and hanging.
The word GARROTING is often used to indicate the forcible compression of the neck by the hands of thieves. The assault is usually made from behind, and the victim is robbed while the throttling proceeds. The brevity of the process explains why death is not more frequent. The word garroting comes from the Spanish; criminal execution in Spain and Italy is usually by means of the GARROTE, a steel collar which is tightened on the neck of the condemned by a screw. The notorious thugs of the East Indies used sometimes a soft loin-cloth, at others a lasso or long thong with a running noose. In Turkey and some other Eastern countries the bowstring is a common mode of execution.
An examination of the reported cases of strangulation and hanging shows a great variety of forms of ligature: cords, ropes, thread, thongs, lassos, flexible twigs, bamboos, leather straps, girdles, turbans, fishing-nets, collars, cravats and other forms of neckwear, bonnet strings, handkerchiefs, sheets, etc. Women have even strangled themselves with their own hair (Case 34). Stones, sticks, coal, and other hard substances have sometimes been inserted in the ligature to increase the pressure (Cases 36, 38, 42, 43, 44). Drunken and otherwise helpless persons have been strangled by falling forward with the neck against a firm substance.
STRANGULATION.
Symptoms and Treatment.
The symptoms and post-mortem appearances in strangulation will vary, according as the deprivation of air is sudden or gradual, partial or complete; and whether there is coincident pressure on the great arteries, veins, and nerves of the neck.
The deprivation of air disposes to asphyxia; pressure on the great arteries by cutting off the supply of arterial blood to the brain disposes to anæmia of the brain and syncope; pressure on the great veins, by preventing the return of blood to the heart, to congestion of the brain and coma; pressure on the great nerves, the pneumogastrics, to syncope. Statistics of hanging show that in about seventy per cent of cases death is by a mixture of asphyxia and coma. While it is probable that the proportion is less in strangulation, yet it is also probable that a mixed result frequently occurs.
Asphyxia is from α priv. and σφίξις, pulse—absence of pulse. Apnœa from α priv. and πνέω, I breathe—absence of breathing. Syncope, συνκοπή, a faint; suspended animation from sudden failure of heart. Coma, κῶμα, deep sleep. Richardson[729] makes the following distinction between asphyxia and apnœa: Asphyxia is difficulty of taking in breath; apnœa is breathlessness. There is asphyxia when the blood from the heart can go to the lungs, but there is no access of air; apnœa, when there is access of air, but the blood fails to reach the lungs. In asphyxia the lungs obstruct the circulation; in apnœa the obstruction is in the heart. In asphyxia the air cannot reach the blood; in apnœa the blood cannot reach the air.