Clinical Research of Controlled Hypotension with Remifentanil in Endoscopic Sinus Surgery Under Isoflurane Balanced Anesthesia

Objective To discuss the validity and controllability of remifentanil inducing and sustaining controlled hypotension under isoflurane balanced anesthesia.Methods Sixty patients underwent endoscopic sinus surgery were randomly divided into two groups:sodium nitroprusside group(N group) and remifentanil group(R group).There were 30 persons in every group.Isoflurane balanced anesthesia was performed in two groups.Radial artery was cannulated for direct and continuous MAP monitoring.Controlled hypotension was induced before the main procedure of surgery.The patients were infused continuously by sodium nitroprusside in N group.The patients were infused continuously by remifentanil in R group.MAP was sustained at 50～70 mmHg.The datum of MAP and HR were noted at the controlled hypotension would begin(T0),blood pressure fell to target 10 min later(T1),20 min later(T2),and 30 min later(T3).The quality of surgical field in terms of blood loss and dryness was rated.The time from beginning controlled hypotension to blood pressure falling to target,and the time from stopping hypotensor to removal of tracheal tube were noted.Results The surgical field scoring of R group was significantly better than that of N group(P0.05).In R group,heart rate decreased(P0.05),while in N group there was reflexible heart rate increasing during hypotension(P0.05).The difference of the time that it took for BP felling to target between the two groups was not statistically significant(P0.05).No statistically significant difference was found between the two groups in time from completion of operation to pulling out the tracheal tube(P0.05).Conclusions It is effective and easily controlled that remifentanil is applied to controlled hypotension of endoscopic sinus surgery under isoflurane balanced anesthesia.