ABSTRACT
Objective To observe the effects of ventilation with low tidal volume and positive end-expiratory pressure (PEEP)in different periods on the postoperative pulmonary function and short-term prognosis in aged patients undergoing abdominal surgery.Methods Sixty aged patients undergoing selective open abdominal surgery scheduled for general anesthesia,21 males and 39 fe-males,were randomized into 3 groups (n =20).Patients in group A received PEEP 1 h after the be-ginning of surgery;patients in group B received PEEP 1 h before tracheal extubation;patients in group C received PEEP intraoperatively.The secretion score in preoperative,postoperative 24 h and 72 h respectively,and the arterial blood gas analysis indexes (PaCO 2 ,PaO 2 ,A-aDO 2 ,PaO 2/FiO 2 calculation)in postoperative 1 h and 24 h were recorded.Results Compared with preoperative,in postoperative 1 h,PaCO 2 increased obviously in all groups,PaO 2 decreased in group B,A-aDO 2 in-creased in group A (P <0.05);in postoperative 24 h,PaCO 2 was significantly increased in group B and C,PaO 2/FiO 2 decreased in group B (P <0.05).Compared with postoperative 1 h,in postopera-tive 24 h,PaCO 2 and A-aDO 2 decreased obviously in group A (P <0.05).There were no differences in postoperative secretions score in between the 3 groups.Conclusion Low tidal volume combined short-range PEEP in different periods of surgery may improve postoperative pulmonary oxygenation. But they had no obvious help with postoperative pulmonary complications.