HALOTHANE ANESTHESIA AND AQUEOUS-HUMOR DYNAMICS IN LABORATORY-ANIMALS

Abstract

Halothane anesthesia decreased intraocular pressure (IOP) by approximately 4 mm Hg in both normal rabbits and monkeys. The administration of N2O or 100% O2 had no effect on IOP. Although P[partial pressure]O2 and PCO2 increased following halothane administration in rabbits, similar blood changes occurred without IOP reduction in control rabbits receiving 100% O2. Outflow facility in both species as measured by tonography remained unchanged by halothane administration. Aqueous humor flows as estimated by tonography decreased by about 39% in rabbits and 31% in monkeys. Posterior chamber aqueous human ascorbate was significantly elevated 90 min after halothane administration in rabbits. The ratio of the aqueous human flow coefficient to diffusion coefficient for ascorbate was reduced 47% following the administration of halothane. Halothane did not alter the in vitro accumulation of 131I-hippuran or 86Rb by rabbit ciliary body-iris preparations.