Pre-induction fentanyl dose-finding study for controlled hypotension during functional endoscopic sinus surgery

Fentanyl can facilitate controlled intraoperative hypotension by its sympatholytic effect in patients undergoing functional endoscopic sinus surgery (FESS). We investigated the effects of different doses of pre-induction fentanyl on controlled hypotension profile during FESS.

This prospective, randomised study included 120 patients randomly allocated to three groups (40 each) based on administration of pre-induction fentanyl; 2 μg/kg group, 3 μg/kg group and 4 μg/kg group. The primary objective was to assess effect on intraoperative heart rate and mean arterial pressure. Use of additional hypotensive agents, surgical field condition and surgeon satisfaction were also analysed.

Controlled hypotension was achieved adequately in all participants. Patients belonging to fentanyl 4 μg/kg group had significantly lower heart rate for the duration of controlled hypotension intraoperatively versus fentanyl 2 μg/kg group (P < 0.05). Trinitroglycerin [TNG] and metoprolol were administered to 3 [7.5%] and 9 [22.5%] patients respectively in the fentanyl 3 μg/kg group, and to 3 [7.5%] and 5 [12.5%] patients respectively in the 4 μg/kg group, compared to 14 [35%] and 20 [50%] in the fentanyl 2 μg/kg group, respectively (TNG, P < 0.001). Surgical field conditions and surgeon satisfaction scores were significantly superior in fentanyl 3 μg/kg and 4 μg/kg groups than in fentanyl 2 μg/kg group.

Pre-induction fentanyl 3 μg/kg and 4 μg/kg group showed superior controlled hypotension facilitation than 2 μg/kg fentanyl during FESS in terms of measurable haemodynamic endpoints and favourable operative conditions, surgeon's satisfaction and sparing of additional hypotensive agents.