asphyxia

noun

1. (countable, uncountable)Loss of consciousness due to the interruption of breathing and consequent anoxia.

   “Asphyxia may result from choking, drowning, electric shock, or injury.”

   “The mattress platform on Davey’s bed fell unexpectedly, “trapping her neck against the upper surface of the side panel of the bed’s base,” Chipperfield explained. “Unable to free herself, she died of positional asphyxia. One of the two gas-lift pistons was defective.””

2. (countable, uncountable)Loss of consciousness due to the body's inability to deliver oxygen to its tissues, either by the breathing of air lacking oxygen or by the inability of the blood to carry oxygen.
3. (countable, obsolete, uncountable)A condition in which an extreme decrease in the concentration of oxygen in the body leads to loss of consciousness or death. Replaced in the mid-20th century by the more specific terms anoxia, hypoxia, hypoxemia and hypercapnia.

   “Hypoxaemia [...is] a deficient oxygenation of the blood; asphyxia from defective oxygenation of the blood.”