Effect of Ether and Barbiturate Anesthesia on the Reaction of Rats to Dextran and of Dogs to Polyvinylpyrrolidone

¹ From the Laboratory of Physical Biology, National Institute of Arthritis and Metabolic Diseases, National Institutes of Health, Bethesda, Maryland

Changes in mean arterial blood pressure and the extravascular appearance of injected dye (T-1824) were followed in rats that received massive intravenous injections of dextran while conscious or while anesthetized with ether or barbiturates. In conscious rats, and during or after ether anesthesia, the usual vasodepression was moderate or absent and the incidence of bluing was high. Rats anesthetized with barbiturates showed severe vasodepression and little bluing. Dogs injected with a small amount of PVP exhibited a significant fall in blood pressure when conscious or when under barbiturate anesthesia, but were partially protected by ether anesthesia. Bluing occurred under all conditions in this species. Change from the supine position to prone or standing did not influence the results. Noradrenaline partially protected rats but increased the severity of the reaction in dogs.