Compare the efficacy of IV clonidine, IV dexmedetomidine and IV magnesium sulfate for attenuation of pressor response during laryngoscopy and intubation under general anaesthesia

Abstract

Aim& Objective: The present study is undertaken to compare the efficacy of Clonidine 1μg/kg, Dexmedetomidine 1μg/kg and Magnesium sulfate 30mg/kg in attenuating the sympathetic responses to laryngoscopy and tracheal intubation. Methodology: The present study was a prospective randomized non- blinded study. After approval from the institutional ethical committee, the study was conducted in 120 patients belonging to ASA I and II of either sex between 18 to 50 years of age undergoing elective surgeries under General anaesthesia in Government General Hospital, Kurnool, Andhra Pradesh. The study was conducted for two years in the Department of Anaesthesia in Kurnool medical college, Kurnool. Results: After informed consent was taken, patients were allocated into four groups - group D for Dexmedetomidine and group C for Clonidine, group M for Magnesium sulfate and group S for Control with 30 in each group. In Group D, 30 patients received 1mcg/kg Dexmedetomidine, in Group C, 30 patients received 1mcg/kg clonidine, Group M received 30mg/kg of Mgso4 and group S received normal saline after standard preoperative anaesthetic evaluation. The values for HR, SBP, DBP, and MAP were obtained just before the administration of the study drug, after the injection of study medications, after induction, just before intubation, immediately after intubation and 1, 3, 5 and 10 min post-intubation and compared among the groups. There was a decrease in HR after Dexmedetomidine administration. When compared among the four groups, we have observed that patients in the Dexmedetomidine group had a decrease in heart rate after study medication was given, after induction, before intubation, whereas, increase in heart rate was seen in groups of clonidine and Mgso4 which is statistically significant. Immediately after intubation, mean HR in all the groups was increased, but less increase is seen in Dexmedetomidine group. After 1min, 3 min, 5 min and 10 mins of intubation, the mean heart rate of the participants in each group was decreasing, but the decrease was more in Dexmedetomidine group than Clonidine and Mgso4 groups, which is statistically significant (p<0.05). When compared among the four groups, from baseline, after the infusion of study medication, after induction, before intubation there was a decrease in mean SBP values in the Dexmedetomidine and Mgso4 groups but remains the same in Clonidine and control groups. Whereas immediately after intubation, the mean SBP was increased in all the four groups, but in this, group D shows least increase in mean SBP followed by group M, C and S which is statistically significant (p<0.05). Conclusion: Dexmedetomidine (1mcg/kg), Clonidine (1mcg/kg) and Magnesium sulfate (30mg/kg) were effective in blunting the hemodynamic response to laryngoscopy in patients undergoing surgical procedures under general anaesthesia.