The effects of prolonged controlled hypotension induced by prostaglandin E1 on renal tubular function

The effects of the prolonged 3-hour and 6-hour controlled hypotension induced by prostaglandin E(1) (PGE(1)) on renal tubular function have been comparatively studied with trimethaphan (TMP; 3-hour hypotensive anesthesia) and enflurane deep anesthesia (6-hour hypotensive anesthesia), using the urine N-acetyl-Beta-D-glucosaminidase (NAG index) and the serum and urine Beta(2)-microglobulin (fractional clearance of Beta(2)-m; Fc-Beta(2)-m) as markers. During 3-hour and 6-hour controlled hypotension PGE(1), NAG index and Fc-Beta(2)-m and urine volume could be maintained without remarkable changes. In the group with TPM, NAG index and Fc-Beta(2)-m significantly increased. The increasing trend was also noted over time in deep anesthesia with enflurane. On 1st postoperative day, Fc-Beta(2)-m significantly increased in PGE(1) group in both 3-hour and 6-hour hypotensive anesthesia, whereas it restored to normal on 2nd postoperative day. Also, in TMP and enflurane deep anesthesia, Fc-Beta(2)-m significantly increased on 1st postoperative day. With the latter, significant increase was also observed on 2nd postoperative day. These results suggest that, in 3-hour and 6-hour controlled hypotension induced by PGE(1), renal tubular function is normally maintained and that it is useful for prolonged controlled hypotensive anesthesia. However, further study is necessary because tubular dysfunction might appear on 1st postoperative day.