The Effect of Ether and Dial-Urethane Anesthesia on the Passage of Sulfathiazole into the Cerebrospinal Fluid

Abstract

The passage of sulfathiazole from the blood to the csf was compared in dogs under ether and under dial-urethane anesthesia after intraduodenal and after intraperitoneal administration of sulfathiazole. Unanesthetized dogs were also studied after intraperitoneal injection. The transfer of sulfathiazole was indicated by the C/B ratios obtained by dividing the csf level by the blood level at the third hour after administration of the drug. It was found that there was an increased level of sulfathiazole in the csf during ether anesthesia. After intraduodenal injection, the C/B ratios were 29% higher with ether anesthesia than dial-urethane. After intraperitoneal injection the C/B ratios under dial-urethane were 20% higher than in unanesthetized animals and under ether they were 80% higher. It was also noted that higher blood sulfathiazole levels were obtained under ether anesthesia. These findings were discussed from the standpoint of the influence of changes in cerebral circulation. It is thought that the transfer of sulfathiazole to the csf may he regulated by the total brain blood flow.