Abstract
OBJECTIVE: To evaluate the effects of peripheral muscle strength on extubation success after cardiac surgery. METHODS: In this prospective cohort study, peripheral muscle strength and Rapid Shallow Breathing Index were assessed at 30 and 10 minutes during a spontaneous breathing trial. Patients were extubated and monitored for 48 hours to verify the success or failure of extubation, and preoperative variables were compared. RESULTS: A total of 66 patients were evaluated, 55 (83%) of whom were classified as successful and 11 (17%) as weaning failures. The Medical Research Council score 30 minutes before the spontaneous breathing trial demonstrated a cut-off value of 44, with a sensitivity of 77%, specificity of 84%, area under the curve of 0.864, and 95% confidence interval (95%CI) 0.69-1.00. The Medical Research Council score 10 minutes before the spontaneous breathing trial showed a cut-off value of 49, with a sensitivity of 55%, specificity of 80%, area under the curve of 0.845, and 95%CI= 0.77-1.00. The Rapid Shallow Breathing Index assessed 10 minutes before the spontaneous breathing trial had a cut-off value of 45, with a sensitivity of 30%, specificity of 70%, area under the curve of 0.476, and 95%CI= 0.22-0.71. CONCLUSION: Peripheral muscle strength may be a useful predictor of extubation success in patients undergoing cardiac surgery.