A prospective randomized controlled trial comparing the effects of dexmedetomidine and fentanyl on attenuation of pressor response during laryngoscopy and intubation

Background: Conduct of general anesthesia requires an ideal premedication and induction agent. Adequate premedication blunts the laryngoscopy and intubation response effectively, which is required in specific groups of people like cardiac patients, hypertensive patients and patients with raised intracranial tension. Our study examines the effectiveness of two drugs, fentanyl and dexmedetomidine in blunting these responses. Objectives: Dexmedetomidine and fentanyl are known for their analgesic and sedative properties. However, there are not sufficient data comparing the two drugs as premedication agents .In the present study we compared the hemodynamic effects of a single pre induction dose of fentanyl and dexmedetomidine on laryngoscopy and intubation. Methodology: Sixty ASA I-II patients were randomized into two groups; Group D (dexmedetomidine group) received 1 µg/kg dexmedetomidine and Group F (fentanyl group) received 2 µg/kg fentanyl intravenously over ten min. The parameters measured included mean arterial pressure, heart rate, systolic and diastolic blood pressure at specified time intervals. The statistical methods used in this study were chi square test and Students unpaired “t” test. Results: Dexmedetomidine was found superior to fentanyl in blunting the cardiovascular response to laryngoscopy and intubation. There was statistically significant difference in heart rate in dexmedetomidine group compared to fentanyl group. The heart rate in group D was 62 ± 47 per min and in group F 76 ± 23 per min, ten minutes post drug administration. Statistically significant differences were also noted in heart rate within one minute after laryngoscopy with Group D (82 ± 13) having a lower value compared to group F (90 ± 50) and also at ten minutes after laryngoscopy and intubation, Group D (63.1 ± 8.70 per min) and Group F (75.07 ± 13.23 per min). Three patients in Group D had bradycardia and had to be supplemented with 0.6 mg atropine. There was no statistically significant differences in mean arterial pressure, systolic and diastolic blood pressures. Conclusion: We conclude that dexmedetomidine (1 µg/kg) is superior to fentanyl (2 µg/kg) as premedication agent in supressing cardiovascular response to laryngoscopy and intubation.