Treinamento muscular respiratório na revascularização do miocárdio

Abstract

Objectives: 1) To demonstrate the impaired ventilatory capacity in the postoperative period in patients submitted to coronary artery bypass grafting (CABG). 2) To test the hypothesis that respiratory muscle training (RMT), performed after surgery, may improve the ventilation capacity in this population. Methods: Randomized study, where 38 patients (age: 65 ± 7 years, 29 male) undergoing coronary artery bypass grafting with cardiopulmonary bypass were divided into two groups: 23 patients in the RMT group and 15 in the control group (CO). The RMT group performed conventional physical therapy + RMT; the CO group performed only conventional physiotherapy. They were assessed at three time points (preoperatively, first postoperative day and hospital discharge), variables: maximal inspiratory and expiratory pressures (MIP and MEP), pain, dyspnea (Borg), peak of expiratory flow (PEF), tidal volume and hospital days. Results: The MIP of the RMT group was higher at discharge (90 ± 26 vs. 55 ± 38 cmH2O, P = 0.01) and the MEP (99 ± 30 vs. 53 ± 26 cmH2O, P = 0, 02). The PEF of the RMT group was higher after hospitalization (237 ± 93 vs. 157 ± 102 fpm, P = 0.02). The tidal volume of the groups was also different at discharge (RMT: 0.71 ± 0.21 vs. CO: 0.44 ± 0.12 liters, P = 0.00). There were no differences between groups regarding days of hospitalization, dyspnea or pain. Conclusions: There is loss of respiratory muscle strength in patients undergoing coronary artery bypass grafting. The RMT, performed in the postoperative period, was effective in restoring the following parameters: MIP, MEP, PEF and tidal volume in this population.