OBJECTIVE General anesthesia causes temporary hypoxia of liver tissue, resulting in several metabolic changes. The purpose of this study was to explore whether the function of hepatic sinusoidal cells, especially the Kupffer and endothelial cells, are damaged following general anesthesia. METHODS Liver sinusoidal cell (LSC) function was evaluated by means of measuring the serum level of activity of the lysosomal hydrolase beta-N-acetyl hexosaminidase before and 24 hours after general anesthesia in 20 patients who underwent orthopedic surgery. RESULTS The only change in liver function which might be of clinical significance was a mild decline in the serum albumin level. CONCLUSIONS Liver sinusoidal cells, especially Kupffer and endothelial cells, most probably remain undamaged after 1 to 5 hours of general anesthesia.