The Effect of Remifentanil– Propofol Compared with Fentanyl– Propofol on Urine Output in Patients Undergoing Lumbar Posterior Spinal Fusion

stability. The purpose of this study was to compare the effects of remifentanil and fentanyl on urine excretion. In a randomized clinical trial, 60 patients, who were candidates for elective surgery for lumbar posterior spinal fusion, were divided randomly into two groups of 30 as remifentanil – propofol (R) and fentanyl- propofol (F). Maintenance of anaesthesia drugs in group R included 100 mcg/kg/min propofol and 0.5- 0.25 mcg/kg/min remifentanil. It included 100 mcg/kg/min propofol and 5- 0.5 mcg/kg/min fentanyl in group F. Vital signs and urine output were recorded every half an hour. The mean age of patients was 49.5± 12.7 years. Urine output in group R showed significantly greater reduction than in group F (p 0.001). Increase of urine output was seen in both groups over the time. Urine output in patients undergoing lumbar posterior spinal fusion who received remifentanil was less compared to the fentanyl group.