Effect of positive end-expiratory pressure ventilation guided by esophageal pressure on pulmonary function after laparoscopic surgery in elderly patients / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of positive end-expiratory pressure (PEEP) ventilation guided by esophageal pressure (Pes) on pulmonary function after laparoscopic surgery in elderly patients.Methods Sixty American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes,aged ≥ 65 yr,with body mass index of 16-28 kg/m2,scheduled for elective laparoscopic radical resection of colorectal cancer,were divided into 2 groups (n =30 each) using a random number table method:PEEP group (group P) and Pes-guided PEEP group (group PP).After induction of anesthesia,the patients were tracheally intubated and mechanically ventilated.The fresh gas flow of oxygen was set at 2 ml/L,tidal volume (VT) was 8 ml/kg,inspiratory/expiratory ratio was 1.0(1.5-2.0),fraction of inspired oxygenwas 60％,the respiratory rate was adjusted,and the end-tidal pressure of carbon dioxide was maintained at 35-45 mmHg.PEEP was set at 5 cmH2O in group P.PEEP was set according to Pes to maintain 5 mmHg ≤ transpulmonary end-expiratory pressure ≤ 10 mmHg in group PP.Forced expiratory volume first second,forced vital capacity,and maximum ventilatory volume were determined after admission to the operating room and at 1,3 and 5 days after operation.Blood samples were collected from the radial artery for blood gas analysis,PaO2 and PaCO2 were recorded,and oxygenation index (PaO2/FiO2) was calculated.Clinical Pulmonary Infection Score was assessed.The development of postoperative pulmonary complications such as pulmonary atelectasis,pneumothorax,respiratory failure,aspiration pneumonia,respiratory infections,pleural effusion and bronchial asthma was recorded.Results Compared with group P,forced expiratory volume first second,forced vital capacity,and maximum ventilatory volume,PaO2 and PaO2/FiO2 were significantly increased at 1,3 and 5 days after operation,and the Clinical Pulmonary Infection Score and incidence of pulmonary atelectasis and respiratory infections were decreased in group PP (P＜0.05).Conclusion Pes-guided PEEP can improve pulmonary function after laparoscopic surgery and decrease pulmonary complications in elderly patients.