Comparative evaluation of oral clonidine and intravenous clonidine premedication in functional endoscopic sinus surgery

Aim: This randomized single blind study was designed to assess the effect of oral and intravenous (IV) clonidine premedication on hemodynamic response to endotracheal intubation, per-operative hemodynamic stability and post-operative analgesic requirements. Materials and Methods: In this randomised single blind study, 60 ASA grade I and grade 2 patients were randomized into two groups. Group O received 3+g/kg oral clonidine 2 hours prior to induction and group I received 3+g/kg iv clonidine 15 minutes prior to induction. Anaesthesia was induced with thiopentone and maintained with oxygen and nitrous oxide with halothane. Heart rate and mean arterial pressure was noted prior to induction and 1 min, 5 min, 10 min, 30 min and every half hourly till the end of procedure. Post-operative sedation and the analgesic requirements were also assessed. Results: Perioperatively the mean heart rate was comparable between the two groups. The mean arterial pressure also was comparable between the two groups at all times except at 1 hr where the mean arterial pressure was higher in the oral group compared to the IV group. There was no difference between the two groups in VAS and sedation scores recorded at 30 min intervals till 2 h postoperatively. Time of requirement of first dose of analgesic was also similar between the groups. Conclusion: the administration of both oral clonidine and iv clonidine results in improved perioperative haemodynamic stability which are comparable in its effects.