Asphyxia (Gr. from a privative and , pulse), literally, a temporary or a final suspension of the motion of the heart, and the pulsation of the arteries. The word is now used exclusively to signify a condition of imperfect or suspended respiration,'in which the blood is no longer arterialized by the influence of the air, irrespective of the motion of the heart, which may continue some time after respiration ceases. The immediate baneful effects of the suspension of respiration arise from the privation of oxgen, and from the retention of the carbonic acid previously formed, which becomes a blood poison. If the circulation be disproportionately augumented, carbonic acid is formed, and being morbidly retained, convulsion and death ensue. If the respiration is unduly and disproportionately augumented, the subject is cooled, for mere pulmonary respiration is a cooling process, by the difference of temperaature of the inspired and expired air; and in this case also the subject dies, but now from loss of temperature. This latter is the case in the asphyxiated patient, if the respiratory movements be unduly hastened.
On the other hand, if in the asphyxiated we excite the circulation, without simultaneously and proportionately inducing the respiratory movements, we destroy the patient by carbonic acid, formed in the course of that circulation, and uneliminated by respiration. This statement explains the injurious and fatal tendency of the warm bath which was formerly recommended in asphyxia, for it is injurious, and has doubtless of itself proved fatal in cases in which the patient without it would have spontaneously recovered.