Comparative study of the effect of oral premedication with clonidine versus diazepam on intraocular pressure following intubation under propofol and suxamethonium

Aim: To study the efficacy of clonidine given orally as premedication on attenuation of rise in intraocular pressure, haemodynamic responses to induction aided with suxamethonium, laryngoscopy and subsesequent tracheal intubation, its sedation and antisialogogue effects and compare with oral diazepam premedication. Patients were randomly divided into two groups i.e. each group of 30 patients. One group was assigned to receive oral clonidine 4-5mcg/kg or diazepam 0.2-0.25mg//kg body weight oral premedication 90mins before induction. Patients received this premedication randomly and in double blinded manner. Pulse rate, blood pressure and intraocular pressure of both eyes were recorded prior to premedication in both the groups. The degree of preoperative sedation was determined according to a Ramsay sedation scale. Patients were asked for oral secretions (salivation) and antisialagogue effect was determined. It has been observed that clonidine premedication is superior to diazepam in attenuating the rise in intraocular pressure, pulse rate, blood pressure (systolic, diastolic and MAP) associated with laryngoscopy and intubation aided with suxamethonium. Clonidine is superior to diazepam in decreasing the IOP and maintaining stable haemodynamic responses following i.v. suxamethonium, laryngoscopy and intubation. Diazepam caused more sedation as compared to clonidine. Clonidine exhibits antisialogogue effect which is not seen with diazepam.