The use of a tourniquet can produce pain and increase in blood pressure. It is known that fentanyl reduces central sensitization, however its effect on blood pressure increase due to tourniquet is unknown. So we investigated the effect of fentanyl on tourniquet-induced changes of mean arterial blood pressure (MBP), heart rate (HR), and cardiac index (CI).

ASA physical status I and II, who were scheduled for knee arthroscopic surgery using a tourniquet, were assigned into control (n = 30) and fentanyl group (n = 30). Anesthesia was maintained with enflurane, N₂O and O₂. Fentanyl was injected 1.5 ug/kg at 10 min before inflation of the tourniquet in the fentanyl group. Changes of the MBP, HR, CI were measured before and 10, 20, 30, 40, 50, 60 min after inflation of the tourniquet.

There were no differences in the baseline values. MBP was increased at 40, 50, 60 min in the control group. At 60 min, MBP was lower in the fentanyl than the control group. HR was decreased at 10 min in the fentanyl group. CI was decreased in all groups after tourniquet inflation. At 60 min, CI was more decreased in the control than the fentanyl group.

Fentanyl injection prior to tourniquet inflation can attenuate the tourniquet induced hemodynamic changes in the knee arthroscopic surgery patients.