A protective-ventilation strategy reduces pulmonary complications after cardiac surgery

Abstract

Introduction Cardiac surgical procedures are associated with a high incidence of postoperative complications, increasing costs and mortality. The aim of this study is to evaluate the effect of a strategy of protective ventilation on pulmonary complications after cardiac surgery. Methods We prospectively evaluated 120 patients immediately after cardiac surgery, presenting hypoxemia and PaO2/FiO2 <250. Patients were randomized to protective or conventional ventilation strategy. Protective strategy: PEEP = 13 cmH2O, recruitment maneuver (RM) with inspiratory pressure amplitude of 15 cmH2O and PEEP of 30 cmH2O. Conventional strategy: PEEP = 8 cmH2O and RM with CPAP = 20 cmH2O. Both patients were ventilated in pressure controlled at 6 ml/kg. Pulmonary mechanic and oxygenation parameters were collected at baseline, 15, 240 and 255 minutes after the start of treatment. Occurrence of respiratory complications was assessed in the first 5 days according to the severity score 1 to 4. Results The protective group compared to the conventional group had better lung compliance (60 ± 17 vs. 48 ± 13 ml/cmH2O, P <0.001) and higher PaO2/FiO2 (431 ± 124 vs. 229 ± 68, P <0.001) at 15 minutes after the start. Also, the protective group had a lower incidence of complications after 5 days of follow-up (grade 2 = 47% vs. 55%, grade 3 = 9% vs. 13%, grade 4 = 0% vs. 3%, P = 0.045). Conclusion A protective-ventilation strategy after cardiac surgery reduces hypoxemia, increases lung compliances and results in less respiratory complications without adverse effects.