Evaluation of efficacy of oral ivabradine for attenuation of hemodynamic response to intubation in hypertensive surgical patients: Effect on rate pressure product as an index of myocardial oxygen demand.

Abstract

Background and aims: An exaggerated hemodynamic response to endotracheal intubation is observed in hypertensive patients, and its attenuation proves challenging. The role of oral ivabradine, a unique heart rate-lowering drug with a favorable hemodynamic profile, is not yet studied. The aim of this study was to evaluate the effect of oral ivabradine on the attenuation of hemodynamic response to endotracheal intubation in hypertensive surgical patients assessed by rate pressure product (RPP), which is a very reliable indicator of myocardial oxygen demand.

Material and methods: Sixty medically controlled hypertensive surgical patients, aged 30-65 years, receiving general anesthesia were divided into two equal groups: Group I received a tablet of ivabradine 5 mg and group C received a placebo tablet 1 hour before induction. Heart rate (HR) and systolic, diastolic, and mean arterial blood pressure (SBP, DBP, and MAP) were recorded at baseline, preoperative, immediately after intubation, 1 min, 3 min, 5 min, and 10 min following intubation. RPP was calculated at the above time intervals. Data were analyzed using the unpaired t-test and the Chi-square test as required, with P < 0.05 considered significant.

Results: The maximum value of RPP after intubation was significantly less in group I (11065.64 ± 606.56) as compared to group C (16774.64 ± 1242.87), P = 0.000. All hemodynamic variables, RPP, HR, SBP, DBP, and MAP, remained significantly less in group I than group C at all time intervals (P = 0.000). These parameters never increased above baseline after intubation in the ivabradine group, indicating effective attenuation of the intubation response.

Conclusion: Premedication with oral ivabradine 5 mg is very effective in attenuating the hemodynamic response to intubation in hypertensive patients.