Effects of beta adrenergic blocking agents upon thermal trauma induced cardiovascular changes.

The cardiovascular changes induced by 15% total body surface area 3 degrees burn have been studied in dogs anesthetized with sodium pentobarbital. The responses observed were a decrease in plasma volume, a decrease in cardiac output, and a slight but insignificant fall in mean arterial blood pressure. Beta adrenergic blockage with propranolol prior to thermal trauma reduced the plasma volume loss, increased the depression of cardiac output, and caused a rise in mean arterial blood pressure. From these results it has been postulated that beta adrenergic stimulation contributes to the plasma volume loss and the slight fall in mean arterial pressure observed following thermal trauma.