The effects of desflurane and propofol on portosystemic pressure in patients with portal hypertension.

UNLABELLED: Physicians perform hepatic venous pressure measurements to guide medical therapy aimed at reducing portal hypertension. These measurements are frequently performed during general anesthesia. Since most general anesthetic drugs reduce liver blood flow, it is likely that hepatic venous pressures will be altered. We therefore examined the effects of two frequently used anesthetic drugs on hepatic venous pressure in a prospective randomized study to determine if pressure measurements taken during general anesthesia were similar to awake values. We studied 21 patients with hepatitis C, excluding patients with hepatofugal flow and portal vein thrombosis. All patients had free and wedged hepatic venous pressures measured awake with sedation and after anesthesia with either propofol or desflurane. Desflurane significantly increased free hepatic venous pressure (11.9 +/- 4.4 to 23.5 +/- 4.1 mm Hg; P < 0.05) and decreased hepatic venous pressure gradient (21.6 +/- 7.4 to 14.7 +/- 5.2 mm Hg; P < 0.05), whereas propofol did not change these variables. We conclude that desflurane, but not propofol, alters hepatic venous pressure measurements from the awake state, significantly increasing free hepatic venous pressure and decreasing the hepatic venous pressure gradient, an indirect measure of portosystemic pressure. Changes in the hepatic venous pressure gradient must be interpreted with caution during desflurane general anesthesia.

IMPLICATIONS: Desflurane reduces the blood pressure difference between the portal and systemic circulations. This can cause errors in assessment of the success of medical therapy of portal hypertension. Propofol has less effect on the difference between the portal and systemic circulation.