New research from Dr. Scott Boback and colleagues at Dickinson College (Pennsylvania) shows that boa constrictors do not use suffocation as a primary means of killing their victims. Rather, by measuring blood pressure and heart activity of the prey, they were able to determine that the snakes restrict blood flow in their victims causing circulatory arrest and a lack of oxygen delivery to vital organs. By preventing blood flow to the brain, the victims faint within mere seconds. Dr. Boback was quoted in BBC News saying , “…an absence of blood flow will cause death more rapidly than suffocation. So it could be considered a much more precise and efficient method of killing.”
Boback SM, McCann KJ, Wood KA, McNeal PM, Blankenship EL, Zwemer CF. Snake constriction rapidly induces circulatory arrest in rats. J Exp Biol. 218: 2279-2288, 2014.