INTRODUCTION. 55 



This is improperly called asphyxia, which is, literally, pulse- 

 less; it is more properly called apncea (suffocation). 



First, when sudden, as from suffocation, or strangulation, or 

 drowning. 



Second, when more slowly, as from pulmonary apoplexy, con- 

 gestion, as when the animal is driven to death, the blood accumu- 

 lates in the vessels of the lungs. Asphyxia means without pulse, 

 while apncea means without breath. 



In what cases is death due to asphyxia? 



In such cases as drowning, inhaling poisonous gases, as smoke, 

 etc., and also choking. In tetanus, or strychnine poisoning, the 

 chest-walls become immovable; again, injury to the spinal column 

 high up in the cervical region (pithing). The entrance of air in 

 the pleural cavity, or a great effusion. 



How does death from apncea occur? 



In acute lung diseases the air cannot pass down; here venous 

 blood circulates in the arteries. In tympanitic colic the gas presses 

 the diaphragm against the lungs and shuts out the air. 



Death beginning at the brain takes place how ? 



It takes place by coma, which means a deep sleep. In coma 

 the function of the brain is suspended and causes secondary trouble, 

 as the want of contraction of the chest-walls. Apoplexy (hemor- 

 rhage in the brain), or pressure of fluids, causes death at the heart, 

 but primarily at the brain, as seen in cerebral meningitis, where 

 the products of the inflammation cause pressure. Certain drugs, 

 as opium, if used improperly, will cause death in this way. Certain 

 waste products, as urea, accumulating in the blood, cause uraemia. 



