A STUDY OF ATTENUATION OF HEMODYNAMIC RESPONSE TO LARYNGOSCOPY AND ENDOTRACHEAL INTUBATION USING INTRAORAL IVABRADINE

Introduction: Laryngoscopy and endotracheal intubation provoke a sympathetic surge that results in transient but significant increases in heart rate and blood pressure. These hemodynamic responses can be detrimental in patients with cardiovascular comorbidities. Ivabradine, a selective I_f channel blocker, reduces heart rate without affecting myocardial contractility or blood pressure. This study was designed to evaluate the effectiveness of intraoral ivabradine in attenuating the hemodynamic response to laryngoscopy and intubation.

Materials and Methods: This prospective, randomized, controlled study was conducted on 30 adult patients (ASA I and II), aged 18–60 years, undergoing elective surgeries under general anesthesia. Patients were randomized into two groups of 15 each: Group I received 5 mg ivabradine intraorally 60 minutes before induction, and Group C received a placebo. Hemodynamic parameters—heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP)—were recorded at baseline, post-drug administration, post-induction, during laryngoscopy, and at 1, 3, and 5 minutes post-intubation. Statistical analysis was performed using SPSS v23 with a p-value < 0.05 considered significant.

Results: The ivabradine group exhibited significantly lower heart rates and attenuated rises in SBP, DBP, and MAP at all time intervals post-induction compared to the control group (p < 0.001). The mean heart rate at intubation was 75.1 ± 6.2 bpm in Group I versus 95.6 ± 8.4 bpm in Group C. No adverse events such as bradycardia or hypotension were observed in either group.

Discussion: Ivabradine effectively attenuated the sympathetic response to laryngoscopy and intubation. The observed reduction in heart rate and blood pressure without significant adverse effects supports its utility as a safe premedicant, particularly in patients where beta-blockers are contraindicated.

Conclusion: Intraoral ivabradine (5 mg) administered 60 minutes prior to induction is a safe and effective strategy to blunt the hemodynamic response to laryngoscopy and endotracheal intubation. Its selective action on heart rate and favorable safety profile make it a valuable tool in anesthetic premedication.