Effect of Oral Clonidine on Hemodynamic Changes due to Laryngoscopy, Intubation and Operative Procedures Stress Response

Context: Endotracheal intubation constitutes a period of extreme hemodynamic stress. Clonidine, α2 adrenergic agonist, slows down the heart rate and leads to a dose‑dependent decrease in systolic and diastolic blood pressure. It has 100% bioavailability following oral administration.

Aims: Effect of oral clonidine on hemodynamic changes due to laryngoscopy, intubation and operative procedures stress response.

Setting and design: This was a prospective, randomized controlled, double‑blind study.

Materials and methods: Fifty patients of either sex, aged 18‑45 years, ASA grade I/II undergoing elective surgeries under general anaesthesia were included. Group A received Clonidine 4 mcg/kg orally induction and group B received 5 ml distilled water. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure, and rate pressure product were noted at baseline, reinduction, postinduction, intubation and thereafter, 1, 3,5,10,15,20,25 and 30min following intubation.

Results: There was a statistically significant difference in heart rate, systolic, diastolic, mean arterial pressure and rate pressure product between two groups. Clonidine group had more stable hemodynamic parameters throughout.

Conclusion: Oral clonidine premedication in the dose of 4 mcg/kg can effectively attenuate the hemodynamic stress response during laryngoscopy, intubation and operative procedures.

Keywords:Oral clonidine; Intubation; laryngoscopy; Pre-induction