IJCS | Volume 32, Nº5, September/October 2019

487 Table 1 - Patients’ characteristics NMES group Control group p Type of surgery Coronary artery bypass grafting, n. (%) 7 (46.67) 5(33.33) 0.45 Valve Replacement, n. (%) 7 (46.67) 10(66.67) 0.26 Coronary artery bypass grafting + valve replacement, n. (%) 1 (6.67) 0 (0) 0.30 Comorbidities, n. (%) 12 (80.00) 10 (66.67) 0.40 Hypertension, n. (%) 7 (46.7) 8 (53.33) 0.71 Diabetes, n. (%) 2 (16.67) 1 (10.00) 0.54 Rheumatic fever, n. (%) 7 (58.33) 5 (50.00) 0.45 Stroke, n. (%) - 1 (10.00) 0.30 Time between admission to ICU and application, mean (SD), (hours) 23.13 (5.24) 22.20 (5.46) 0.64 Male sex, n. (%) 9 (60.00) 5 (33.33) 0.14 Age, mean (SD), (years) 49.87 (14.37) 50.93 (14.56) 0.84 Left ventricular ejection fraction, mean (SD) 57.60 (10.49) 61.07 (7.84) 0.31 Cardiopulmonary bypass time, mean (SD) (min) 106.33 (15.52) 104.00 (17.95) 0.70 Intravenous Drugs at sessions, n. (%) 8 (53.33) 9 (60.00) 0.71 Dobutamine, n. (%) 5 (62.50) 4 (44.44) 0.69 Dopamine, n. (%) 4 (50.00) 3 (33.33) 0.66 Norepinephrine, n. (%) 3 (37.50) 2 (22.22) 0.62 Nipride, n. (%) 0 (0) 2 (22.22) 0.14 Tridil, n. (%) 1 (12.50) 0 (0) 0.30 NMES: neuromuscular electrical stimulation, SD: standard deviation, ICU: intensive care unit; Chi-Square Test; Independent Sample Test. Cerqueira et al. NMES after cardiac surgery Int J Cardiovasc Sci. 2019;32(5):483-489 Original Article responses than other classically used protocols with high and moderate frequencies, similar to that used in the present study. In this aspect, another factor that must be taken into account is the stimulated muscle mass, because larger muscular masses could lead to higher physiological responses. 23 However, regardless of the variety of parameters used in the studies, a systematic review of NMES efficacy in critically-ill patients indicates that this is a relatively safe method for use in this type of patient, 21 which is in agreement with our data. Thus, we proposed that NMES be used as post- surgical therapy considering the possible benefits related to the use of this resource, as a shorter period of exercise restriction, smaller strength decline and faster recovery of muscle strength, consequently resulting in higher tolerance by patients to recover their ambulation capacity, functional levels and performance of activities of daily life. Study limitations This study was limited by the use of a single session of an NMES protocol. Other modalities of NMES should be tested, as well as different times of use in patients at the postoperative period of cardiac surgery. Conclusion In the present study, NMES did not promote changes in hemodynamic and respiratory responses in the