Comparison of Oral Moxonidine versus Clonidine in Adults Undergoing General Anaesthesia: A Double-blinded Randomised Controlled Study

Introduction: Anxiolysis helps in reducing perioperative adverse events. Clonidine is an established anxiolytic premedication but Moxonidine with a similar mechanism, has not been explored for the same. Moxonidine is an imidazoline receptor agonist which plays a significant role in modulating anxiety and stress response. Aim: To evaluate the anxiolytic action of 0.2 mg oral Moxonidine versus 0.1 mg oral Clonidine given as premedication to adults undergoing general anaesthesia for elective surgeries. Materials and Methods: A randomised double-blinded controlled study was conducted at the Department of Anaesthesiology, N F Railway Central Hospital, Guwahati, Assam, India from January 2024 to December 2024 on a sample size of 44 patients aged 30 to 55 years, further divided into 2 groups-Group M (n=22) who received 0.2 mg Moxonidine and Group C (n=22) who received 0.1 mg Clonidine. In the preoperative period, the anxiety score calculated using Amsterdam Preoperative Anxiety and Information Scale (APAIS), Heart Rate (HR), Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), Mean Arterial Pressure (MAP), Respiration Rate (RR), Oxygen Saturation (SpO2 ) measured before and 90 minutes after administration of the drug. Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) version 22.0 and a p-value <0.05 was considered significant. Results: Demographic profiles were comparable among both the groups with insignificant p-value. The mean anxiety score was 23.82±4.32 in the Clonidine group and 22.09±5.71 in the Moxonidine group (p-value=0.264). Post-intervention, the anxiety scores significantly reduced within both groups (p-value <0.001), with no significant difference between the groups (p-value=0.838). The mean change in HR from baseline to intubation, five minutes, 10 minutes, 15 minutes were -0.45, 2.91, 4.77, 7.68 in Moxonidine group and -1.73, 3.23, 8.77, 7.68 in the Clonidine group, respectively. The mean change in MAP from baseline to intubation, five minutes, 10 minutes, 15 minutes were -6.27, 5.5, 13.64, 12.09 in Moxonidine group and -1.36, 5.05, 10.19, 11.95 in Clonidine group, respectively. The mean respiratory rate and SPO2 before intervention was 12.27±0.70 breaths per minute (bpm) and 99.64±0.73% in the Clonidine group, respectively and 13.18±2.02 bpm, 99.68±0.65% in the Moxonidine group, respectively. Postintervention the mean respiratory rate and SPO2 was 12.27±0.70 bpm and 99.64±0.73% in Clonidine group, respectively and 12.27±0.70 bpm, 99.73±0.63% in Moxonidine group, respectively. Thus, the changes in HR, MAP, RR and SPO2 at various intervals were not significantly different between the Clonidine and Moxonidine groups (p>0.05 for all). Conclusion: Oral Moxonidine provides similar anxiolysis as compared to oral Clonidine. The intubation blunting response is also similar. Further studies are required for establishment of equivalent doses.