Background: Functional Endoscopic sinus surgery (FESS) is a surgical intervention during which controlled hypotension can improve visibility. Magnesium sulfate is used for controlled hypotension. Pregabalin is also effective in hypotensive anesthesia.
Objectives: This study aimed to detect the effect of single preoperative oral pregabalin versus intravenous magnesium sulfate to facilitate induced hypotension during functional endoscopic sinus surgery.
Patients and methods: In a randomized, double-blind, prospective study, 60 patients of either sex were divided into 2 equal groups. Group P received an oral pregabalin capsule of 150 mg 30 minutes before general anesthesia. Group M received a single-dose 2 grams of magnesium sulfate 30 minutes before induction of anesthesia. The primary outcome was the total intraoperative consumption of nitroglycerin required to maintain the mean arterial blood pressure (MAP) at the range of 55– 65 mmHg. The secondary outcomes were the quality of the surgical field assessed by the Fromm and Boezaart grading scale, surgeon satisfaction assessed by the five-point Likert scale, and the visual analog pain scores (VAS).
Results: The pregabalin group P showed statistically significant lower nitroglycerine doses (1.3±1.2 mg) compared to group M (3.3±1.5 mg) with a P value of <0.001. The surgical field quality and the surgeon satisfaction scales showed statistically significant better scores in group P (1.7±0.6 and 5±0.6 respectively) than in group M (3.2±0.9 and 2.1±0.6 respectively) with P values of (0.023 and 0.001 respectively). The VAS showed statistically significant lower scores in group P (1.3±0.9) compared with group M (3.4±0.6) with a p value= 0.001.
Conclusion: A single preoperative pregabalin dose was more effective than magnesium sulfate in reducing the total intraoperative consumption of nitroglycerin. It also provides a dryer surgical field that achieves better surgeon satisfaction and provides postoperative analgesia.