Effects of pulmonary static inflation with different pressures on postoperative lung function in patients undergoing cardiac valve replacement with cardiopulmonary bypass / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effects of pulmonary static inflation with different pressures on postoperative lung function in patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB).Methods Sixty ASA Ⅱ or Ⅲ patients,aged 26-70 yr,weighing 47-78 kg,undergoing elective cardiac valve replacement with CPB,were randomly divided into 2 groups (n =30 each)pulmonary static inflation with 5 cm H2O group (group L) and with 10 cm H2O group (group H).In L and H groups,pulmonary static inflation was performed with the pressure maintained at 5 and 10 cm H2O,respectively,after stopping mechanical ventilation during CPB.Arterial blood samples were taken before skin incision and at 1,3 and 6 h after termination of CPB for blood gas analysis.The alveolar-arterial oxygen pressure difference (D(A-a)O2),respiratory index (RI) and oxy.genation index (OI) were calculated.The indwelling time of endotracheal tube after operation and duration of ICU stay were recorded.Results Compared with group L,D(A-a)O2 and RI were significantly decreased and OI was increased at 1,3 and 6 h after termination of CPB,the incidence of OI less than 300 mm Hg was decreased (P ＜ 0.05),and no significant change was found in the indwelling time of endotracheal tube after operation and duration of ICU stay in H group (P ＞ 0.05).Collusion Pulmonary static inflation with 10 cm H2O can better improve postoperative pulmonary diffusion function than with 5 cm H2O in patients undergoing cardiac valve replacement with CPB.