Relationship Among Recovery Oxygen, Oxygen Missed, Lactate Production and Lactate Removal During and Following Severe Hypoxia in the Unanesthetized Dog

¹ From the Department of Physiology, University of Illinois College of Medicine, Chicago, Illinois

An experiment was designed to test the ‘O₂debt’ hypothesis. Oxygen consumption and plasma lactate were measured before, during and following hypoixa in unanesthetized spinally transected dogs. The O₂ consumption was depressed during hypoxia and returned toward control levels during recovery. Lactate levels increased during the hypoxia and returned to the control during recovery. Oxygen missed was correlated with the excess consumption of recovery. A highly significant relationship was found which indicated that the larger the depression in O₂ consumption during hypoxia, the greater was the depression during the recovery period and the more prolonged the return to control levels. Oxygen missed during hypoxia was compared to lactate production. A significant relationship was found. Lactate removal was compared to excess consumption of recovery. No correlation existed between lactate removal and recovery O₂ consumption. The authors postulate the presence of a metabolic governor which controls the rate of O₂ uptake.