Metoprolol na atenuação de bucking, tosse e respostas cardiovasculares durante a extubação traqueal: ensaio clínico randomizado, duplamente encoberto e placebo controlado

Abstract

Background: awakening from anesthesia is a critical moment in which several harmful respiratory and cardiovascular manifestations can occur to the patient. Currently, there is no well-established preventive and protective technique to avoid these manifestations. Objective: To evaluate the effect of pre-extubation metoprolol on bucking rate, degree of cough, respiratory complications and hemodynamic responses in the peri-extubation period. Method: randomized, double-blind, placebo-controlled clinical trial, in a tertiary referral center in Brasilia-DF, Brazil. Recruitment: June 2021 to December 2021. Two hundred and seven participants undergoing general anesthesia and extubation in the operating room were randomized (1:1), received 5 mg of intravenous metoprolol or 0.9% saline bolus for three minutes, thirteen minutes before extubation. The primary outcome was the comparison of the bucking rate at the time of extubation between groups. Cough degree, respiratory complications and peri-extubation hemodynamic responses were also assessed. Results: Patients who received metoprolol had a significant reduction in the incidence of bucking (43.1% vs 64.8%, RR 0.66, 95% CI 0.51 to 0.87, P = 0.003, NNT 4.62), besides having better levels of satisfaction on the scale based on the occurrence of cough, where 94.1% did not cough or had a mild cough after extubation versus 68.6% in the control group. Only 5.9% of patients had moderate or severe cough after extubation compared to 31.4% in the control group (RR 0.19; 95% CI 0.08-0.43, P<0.001). Patients who received metoprolol also had a lower incidence of tachycardia (9.8% vs 73.3%, RR 0.13, 95% CI 0.07 to 0.24, P < 0.001, NNT 1.57) and hypertension (16, 7% vs 45.7%, RR 0.36. 95% CI 0.22 to 0.59. P<0.001). No significant difference was observed between the groups in terms of adverse effects. Conclusions: Metoprolol proved to be a safe and effective alternative in the prevention and attenuation of cardiorespiratory responses during and after orotracheal extubation. Trial Registration: approved by the National Council of Research Ethics - CONEP (CAAE: 37700620.5.0000.8153) and registered in the Brazilian Registry of Clinical Trials (ReBEC RBR-3xk4qkq).