CARDIAC OUTPUT IN ACUTE EXPERIMENTAL METHEMOGLOBINEMIA

Abstract

Methemoglobinemia induced in normal anesthetized dogs by intravenous infusions of aniline resulted in a decreased arterial oxygen content and a marked increase in cardiac output. Heart rate, arterial pressure, blood viscosity, and oxygen consumption increased, while total peripheral resistance and arteriovenous oxygen difference decreased. The elevation of cardiac output occurred in spite of the fact that the hematocrit level and blood viscosity increased. Ganglion-blocking doses of pentolinium bitartrate did not significantly alter the cardiovascular responses to the methemoglobinemia.