Blood pressure in unanesthetized bacterially infected rabbits: effects of antipyretic drug therapy.

It has previously been determined that an intraperitoneal infusion of a combination of antipyretic-anti-inflammatory drugs, sodium salicylate and acetaminophen, increases the survival rate of rabbits injected with Pasteurella multocida, a gram-negative bacterium. To determine whether the increased survival rate was attributable to antihypotensive effects of the drug therapy, aortic arch blood pressure was measured continuously in unanesthetized rabbits before and after an injection of bacteria. The results of this investigation revealed that the injection of bacteria produced a fall in mean arterial pressure of 13 mm Hg in both drug- and saline-infused rabbits. These results exclude the possibility that the increased survival rate of rabbits injected with P. multocida, when infused with sodium salicylate and acetaminophen is attributable to the prevention in the fall in mean arterial pressure.