Labetalol (preoperative oral and intraoperative infusion) overrides nitroglycerine infusion for hypotensive anesthesia during functional endoscopic sinus surgery

Abstract

Objective The objective of this study was to evaluate preoperative and intraoperative changes of heart rate (HR) and blood pressure (BP) measures, amount of bleeding, surgical field visibility, and surgeons’ satisfaction during FESS performed under hypotensive anesthesia (HA) for mild hypertensive patients. Patients and methods A total of 104 patients were randomly divided into two groups: group L included patients premedicated by 200 mg oral labetalol 2 h preoperatively and intraoperative labetalol infusion at a rate of 6 ml/min to provide 0.2 mg/kg/h. Group N included patients who received a placebo tablet 2 h preoperatively and nitroglycerine infusion at a rate of 21 ml/h to provide 0.5 µg/kg/min. The study outcome included control of induction and intubation-induced BP and HR responses throughout the surgery. Results Labetalol premedication significantly decreased preoperative HR and BP than baseline measures and significantly reduced induction and intubation-induced pressor responses compared with placebo. The applied protocols of HA allowed significant reduction of BP, intraoperative bleeding, and improved field visibility that satisfied the surgeons. Labetalol infusion significantly lowered intraoperative HR and BP than baseline and preoperative measures. Labetalol infusion significantly lowered intraoperative HR compared with nitroglycerine infusion. Patients who received labetalol infusion had significantly lower HR and mean arterial pressure at the time of extubation and 1 h postoperatively compared with patients of group N. Conclusion Oral labetalol premedication has effectively blunted induction and intubation-induced pressor reflex. Labetalol infusion effectively reduced intraoperative HR and BP, reduced intraoperative bleeding, and improved field visibility during FESS better than nitroglycerine infusion. Labetalol significantly improved emergence from anesthesia with maintenance of significantly lower postoperative HR and BP than patients who received nitroglycerine.