Hyperventilation With Oxygen–a Possible Cause of Cerebral Hypoxia

Cerebral Circulation and Metabolism During Thiopental Anesthesia and Hyperventilation in Man*

“…A great deal has been written on this subject, almost all of which is speculation. It is undoubtedly true that hyperventilation can cause cerebral vasoconstriction, can severely reduce cerebral Po2 [as measured by an oxygen electrode inserted in the cerebral cortex (42), or by measurements of blood draining the brain (38)], and can reduce psychomotor function and impair consciousness (43). In anesthetized men, hyperventilation appears by clinical criteria to deepen the level of anesthesia (4).…”

The Cerebral Vascular Response to Reduction in Arterial Carbon Dioxide Tension*

“…In view of the demonstrated sensitivity of the cerebral vessels to hypocapnia, it is probable that the impairment in mental function is related, at least in part, to deficient cerebral blood flow. Recent animal studies have further stressed the importance of the hypoxia in brain tissue which accompanies hyperventilation, even with 100 per cent oxygen as the inspired gas (27,28).…”

Response of the Cerebral Circulation to Hypocarbia in Postasphyxia Newborn Lambs

“…Despite the availability of several studies, disagreement still exists about whether reduction of CBF with hypocarbia is harmful. Work in adult animals and humans has shown decreases in cerebral tissue Po2, the development of abnormalities in electroencephalographic recordings, and decreased CMRO2 during hyperventilation (24)(25)(26)(27)(28). These data were supported by the demonstration by Reuter and Disney (4) of decreased CMR02 with acute hypocarbia in newborn puppies.…”