Introduction: Laryngoscopy and endotracheal intubation is invariably associated with haemodynamic stress response which may have severe consequences in patients with comorbidities. Various drugs have been tried to attenuate this response. Ease of use, cost effectiveness and minimal side effects are some important considerations while choosing an agent. In this study we have compared the efficacy of oral clonidine with IV fentanyl and IV butorphanol in attenuating the stress response to laryngoscopy and intubation.

Materials and Methods: This is a prospective, randomised, comparative study carried out on 75 patients aged 20–60 years, ASA I/II physical status, scheduled for elective surgery. These patients were randomly allocated into three groups- GROUP A received IV Fentanyl 2mcg/kg and GROUP B received IV Butorphanol 40 mcg/kg five mins prior to induction respectively. GROUP C received Oral Clonidine 4 mcg/kg 90 mins prior to induction. All thepatients were assessed for heart rate, systolic blood pressure and diastolic blood pressure before induction, during laryngoscopy, after intubation at 1 min, 2 min, 3 min and 5 minrespectively. Statistical analysis: The data was compared and analysed using Kruskal-Wallis test.

Results: There was an increase in the hemodynamic parameters post laryngoscopy and intubation in all the groups.Astatistically significant difference in the mean heart rate, systolic blood pressure and diastolic blood pressure was observed; the increase being significantly lower and short-lived in the oral clonidine group compared to the other two groups. Although all the three drugs were effective in attenuating the pressor response, oral clonidine was moreeffective and consistent compared to IV fentanyl and IV butorphanol.

Conclusion: Oral clonidine 4mcg/kg given 90 mins prior to induction is more effective than IV fentanyl and IV butorphanol in blunting the hemodynamic response to direct laryngoscopy and intubation without causing any significant side effects.