ASPHYXIA (Gr.) means literally a cessation of the pulsation from any cause, but is usually applied to the condition resulting from the blood in the body no longer being brought into the proper relations to the atmospheric air by respiration, so as to allow a sufficiently free exchange of carbonic acid for oxygen. See RESPIRATION. A., or suspended respiration, may result'from several causes. No air, or but a scanty supply, may be admitted, as in strangulation, drowning, choking, or disease in the windpipe; the chest may be prevented from expanding either from a superincumbent weight or paralysis, as when a man breaks the upper part of his neck above the phrenic nerve, thus paralyzing the diaphragm; and again, although there may be every capacity for respiration, the air itself may be in fault, and contain too little oxygen in proportion to other elements, as carbonic acid or sulphuretted hydrogen, which net as poisons when inhaled. Aquatic animals may be asphyxiated either-by depriving the water they inhabit of oxygen, or impregnating it with the gases just mentioned.
As this condition of A. advances, in drowning or otherwise, the small vessels of the lungs become gorged with blood, which the heart has no longer power to force freely through them, the right side of the heart and pulmonary artery become filled with blood, while but little returns to the arterial or left side of the heart.
The person becomes pallid, except in such .vascular parts as the lips, checks, and finger-tips, which become blue; and soon the blood, no longer aerated, produces the phenomena of poisoning by carbonic acid. After some slight convulsive movements,
the person becomes, insensible, the pulsations of the heart grow gradually feebler, and at last cease altogether. In man this occurs in from a minute and a half to five minutes. Sonic persons, no doubt, as the Ceylon divers, can by habit do without a fresh supply of air for a longer period ; and some diving animals have an arrangement of blood vessels by which they are enabled to be under water for a long time. Restoration of asphyxiated persons may be attempted with hopes of SUCINS.5 at a very long period after apparent death. The object of all methods is of course to fill the lungs with fresh air. One of the most efficient is that of the late Marshall Hall. lay the person down at once with his head on his left arm, open the mouth, and draw the tongue forwards, then roll him gently over towards the left till he is nearly quite over on his face, then on to his back again, making the body by its own weight compress the chest, which, on expansion by its elasticity, fills with air. Repeat this about 15 times in a minute. This remedy nearly superseded all others for the restoration of still-born infants and other asphyxi ated persons, before the introduction of the method of Dr. Sylvester, an account of which is given under RESPIRATION, ARTIFICIAL.