Comparison of Clonidine and Metoprolol Effectiveness on the Control of Post-Operative Blood Pressure in Otorhinolaryngology-Head and Neck Surgeries: A Clinical Trial

Objectives: Adequate control of hemodynamic parameters in patients undergoing otolaryngology-head and neck (OLHN) surgeries is one of the objectives of peri-operative anesthesia management. In this context, we seek to evaluate the effectiveness of metoprolol compared to clonidine in the post-operative control of systolic (SBP) and diastolic (DBP) blood pressures, and heart rate (HR), when these medications are used in the immediate pre-operative period. Method: this is a randomized double-blind clinical trial. Patients over 18 years old, according to the American Society of Anesthesiologists Physical Status Classification (ASA) I or II, who would undergo OLHN surgery, presenting with greater than 140 mmHg (SBP) or 90 mmHg (DBP), upon arrival at the surgical ward, were included in the study. 46 patients were randomized into two groups (C or M) who received clonidine (75 or 150 mcg) or metoprolol (5 or 10 mg), respectively. The averages of SBP, DBP and HR were compared between groups upon arrival at the post anesthesia care unit (PACU) and four hours post-surgery. Results: In group C, SBP (127.7 ± 18.8 vs 137.3 ± 14.1 mmHg, p = 0.03) and DBP (73.1 ± 15.46 vs 82.6 ± 7.9 mmHg, p < 0.01) were lower, when compared with group M. No difference was observed in HR immediately upon PACU arrival. In addition, for four hours post-surgery, no change was noted in the SBP, DBP or HR. Conclusion: metoprolol was less effective than clonidine in reducing systolic and diastolic blood pressures in the immediate post-operative period of OLHN surgeries.