Hemodynamic changes in the dog connected to a dialysis circuit: influence of the body temperature

Eighteen sessions in 9 mongrel dogs were carried out to know the hemodynamic effects produced by body temperature variation, when blood passes through a dialysis circuit with a Cuprophan dialyzer, without dialysate contact. The decrease of 2 degrees C in body temperature caused a decrease in heart rate and cardiac index (-8.6 and -17.6%, respectively) without significant changes in blood pressure. The increase of 2 degrees C in body temperature increased the heart rate, the cardiac index and the first derivative of ventricular pressure (+14.8, +17.3 and +27.8%, respectively) with a decrease of 13.6% in the systemic vascular resistance. Blood pressure did not change significantly. We conclude that the dog maintains the hemodynamic stability by two different mechanisms: when body temperature rises, by increasing the cardiac index; when body temperature decreases, by increasing the systemic vascular resistance.