Ketamine in hypovolemic dogs

The cardiopulmonary consequences of hemorrhagic hypovolemia and the subsequent administration of ketamine were evaluated in eight dogs; five additional dogs served as controls. Heart rate (HR), systemic vascular resistance, breathing rate, minute ventilation (VE), Pao2, alveolar-arterial oxygen tension gradient, and oxygen extraction ratio increased, while arterial and pulmonary pressures, CVP, cardiac output, oxygen transport, P o2, Paco2, mixed venous oxygen content, bicarbonate, and base deficit decreased in response to hypovolemia. Ketamine administration was associated with a significant increase in HR, arterial and pulmonary BP, and Paco2, and a significant decrease in VE (transient), Pao2 (transient), and pH. Ketamine supported cardiovascular function well, did not impair tissue oxygenation, and caused only transient respiratory depression in these hypovolemic dogs.