Controlled hypotensive anesthesia for functional endoscopic sinus surgery : a new protocol for dexmedetomidine administration

Abstract EN

Objective The aim of the study was to conduct a comparative investigation to evaluate the effi cacy of dexmedetomidine as a hypotensive agent by presenting a new protocol for administration versus the conventional protocol in functional endoscopic sinus surgery (FESS).

Materials and methods Forty patients of ASA grade I–II scheduled for FESS were equally randomly assigned to two groups: the DEX group and the DEXnew group.

The DEX group received dexmedetomidine at 1 g/kg diluted in 10 ml normal saline 10 min before surgical incision (SI), followed by intravenous infusion of dexmedetomidine at 0.2–0.7 g/kg/h according to the hemodynamic status and BIS.

The DEXnew group received dexmedetomidine at 1 g/kg diluted in 10 ml normal saline 10 min before SI, followed by intravenou s top-up doses of 1/4 of the loading dose over 2 min in the form of intravenous shots to maintain MAP between 65 and 70 mmHg.

Mean arterial blood pressure (MAP), heart rate (HR), cortisol level, fentanyl consumption, emergence time, and recovery from anesthesia (modifi ed Aldrete score) were recorded.

The sedation score and time to fi rst analgesic request were recorded.

Results In the DEX group there was a statistically signifi cant decrease in MAP at 30, 45, 60, and 90 min after SI in comparison with preoperative MAP.

In the DEXnew group also there was a statistically signifi cant decrease in MAP at 30, 45, 60, and 90 min after SI in comparison with preoperative MAP.

There was a nonsignifi cant difference as regards intraoperative fentanyl and postoperative pethidine consumption between the two groups.

There was a signifi cant decrease in the total amount of consumed dexmedetomidine in the DEXnew group (118 ± 14.6 g) compared with the DEX group (189.4 ± 22.7 g).

Emergence time was signifi cantly shorter in the DEXnew group (5.34±1.83 min) compared with the DEX group (9.45 ± 2.02 min).

Conclusion This modifi ed protocol of dexmedetomidine administration is safe and effective for controlled hypotension, providing an ideal surgical fi eld during FESS.

Compared with the conventional protocol of dexmedetomidine administration, the modifi ed protocol offers fewer side effects; signifi cant decrease in dexmedetomidine consumption, faster emergence time, and better modifi ed Aldrete scores