Purpose: Physiological principles support lower pulmonary and muscle strength function after on-pump surgery. This principle would increase the number of postoperative complications. The purpose of this study was to compare pulmonary function and respiratory muscle strength in postoperative patients after on-pump and off-pump coronary artery bypass surgery.
Methods: Twenty-five patients who underwent bypass surgery were divided into off-pump (G1) on-pump and (G2) groups. Pre- and postoperative (third day) pulmonary measures included tidal volume (TV), slow vital capacity (VC), and minute volume (MV), and respiratory muscle strength included Pimax e Pemax. These measurements were used for analysis.
Results: Both groups were similar with respect to age, sex, ejection fraction, and mean number of grafts. There were statistical differences between the G1 and G2 groups for pulmonary function with TD (TD = G1: 0.49L vs G2: 0.40L; p = .005), MV=(G1: 9.50L/min vs G2: 7.68L/min; p = .02), and respiratory muscle strength from Pi max (G1: -65.40 cmH2o vs G2: -41,90 cmH2o; p = .01).
Conclusions: The present data support the concept that although there are clinical advantages to off-pump surgery, he pulmonary postoperative treatments have to consider these surgical characteristics.