Positive Pressure Therapy to Optimize LUNG Function After Heart Surgery

The most common cardiac surgeries are myocardial revascularization and valve replacement or plastic surgery. In the postoperative period of cardiac surgeries, the incidence of pulmonary complications ranges from 30% to 50% and is associated with increased length of hospital stay and morbidity and mortality. To reduce or minimize the occurrence of these complications, respiratory physiotherapy employs positive pressure reexpansion therapies, such as continuous positive airway pressure (CPAP) and positive pressure support with positive end-expiratory pressure (PS+PEEP). The goal of this clinical trial is to compare the effects of two positive pressure therapies, CPAP versus PS+PEEP, on the incidence of pulmonary complications in patients in the postoperative period of myocardial revascularization and valve replacement or plastic surgery, with mild to moderate pulmonary dysfunction. The main question it aims to answer is: Do patients in the immediate postoperative period of myocardial revascularization or valve replacement/plastic surgery, exhibiting mild to moderate pulmonary dysfunction, experience a comparable reversal of pulmonary conditions when treated with PS+PEEP versus CPAP? Participants will undergo the following assessments: spirometry, respiratory muscle strength testing, handgrip strength testing, and electrical impedance tomography. In the immediate postoperative period, participants will be randomized into two treatment groups: • Control Group PS+PEEP - application of 4 sets of 20 repetitions with PS to provide a tidal volume equal to 10ml/kg of predicted body weight, PEEP equal to 10 cmH2O, and inspired oxygen fraction (FiO2) to achieve peripheral oxygen saturation (SpO2) between 92-94%; • Experimental Group CPAP - application of CPAP at 10 cmH2O with FiO2 to achieve SpO2 between 92-94% for 30 minutes.