Effect of delayed hyperventilation on experimental cerebral infarction

Experimental cerebrovascular occlusion utilizing a double clip technique was performed in two groups of rhesus monkeys. Normocarbia was maintained in one group, and the experimental group was hyperventilated to a P_aCO₂ of 25 mm. Hg for three hours after an initial hour of normocarbia. All animals survived but exhibited evidence of cerebral infarction. After seven days, each animal was sacrificed and the area of infarction was measured. There was no statistical difference between the two groups, giving rise to the conclusion that delayed hyperventilation does not reduce the area of infarction in acute cerebrovascular occlusion.