Background
Reflex tachycardia that occurs during nitroglycerin-induced hypotensive anesthesia in functional endoscopic sinus surgery (FESS) increases both the risk of intraoperative bleeding and the duration of surgery. Our clinical trial aimed to compare the effect of oral ivabradine versus oral propranolol as a premedication before nitroglycerin-induced hypotensive anesthesia on the reduction of reflex tachycardia in FESS.
Methods
In this clinical, comparative, prospective, randomized, controlled, double-blinded study, 40 patients were divided into two equal groups (20 each); group P received oral propranolol (10 mg tablet) and group I received oral ivabradine (5 mg tablet) in the evening before the surgery and 1 hour before the induction of anesthesia.
Results
The reduction in heart rate (HR) was statistically significantly higher in group I than in group P. Conversely, the reduction in mean blood pressure (MAP) was statistically significantly higher in group P than in group I at baseline (pre-induction). However, after that, MAP reduction was statistically non-significant between both groups. Meanwhile, there was no statistically significant difference between both groups as regards duration of surgery, duration of deliberate hypotension, intraoperative NTG infusion doses, and the amount of bleeding.
Conclusion
Premedication with oral propranolol 10 mg or oral ivabradine 5 mg before FESS proved to be safe and effective in the reduction of reflex tachycardia that occurs during controlled nitroglycerin induced hypotensive anesthesia in FESS. However, ivabradine was more effective with higher safety profile than propranolol.