Chengmi Zhang1, Fengying Xu2, Weiwei Li1, Xingyu Tong1, Ran Xia1, Wei Wang1, Jianer Du1, Xueyin Shi1. 1. From the Department of Anesthesiology and Critical Care Medicine, Xinhua Hospital, affiliated with Shanghai Jiaotong University School of Medicine, Shanghai, China. 2. Department of Anesthesiology, No. 971 Hospital of People's Liberation Army Navy, Qingdao, China.
Abstract
BACKGROUND: The optimal positive end-expiratory pressure (PEEP) to prevent postoperative pulmonary complications (PPCs) remains unclear. Recent evidence showed that driving pressure was closely related to PPCs. In this study, we tested the hypothesis that an individualized PEEP guided by minimum driving pressure during abdominal surgery would reduce the incidence of PPCs. METHODS: This single-centered, randomized controlled trial included a total of 148 patients scheduled for open upper abdominal surgery. Patients were randomly assigned to receive an individualized PEEP guided by minimum driving pressure or an empiric fixed PEEP of 6 cm H2O. The primary outcome was the incidence of clinically significant PPCs within the first 7 days after surgery, using a χ2 test. Secondary outcomes were the severity of PPCs, the area of atelectasis, and pleural effusion. Other outcomes, such as the incidence of different types of PPCs (including hypoxemia, atelectasis, pleural effusion, dyspnea, pneumonia, pneumothorax, and acute respiratory distress syndrome), intensive care unit (ICU) admission rate, length of hospital stay, and 30-day mortality were also explored. RESULTS: The median value of PEEP in the individualized group was 10 cm H2O. The incidence of clinically significant PPCs was significantly lower in the individualized PEEP group compared with that in the fixed PEEP group (26 of 67 [38.8%] vs 42 of 67 [62.7%], relative risk = 0.619, 95% confidence intervals, 0.435-0.881; P = .006). The overall severity of PPCs and the area of atelectasis were also significantly diminished in the individualized PEEP group. Higher respiratory compliance during surgery and improved intra- and postoperative oxygenation was observed in the individualized group. No significant differences were found in other outcomes between the 2 groups, such as ICU admission rate or 30-day mortality. CONCLUSIONS: The application of individualized PEEP based on minimum driving pressure may effectively decrease the severity of atelectasis, improve oxygenation, and reduce the incidence of clinically significant PPCs after open upper abdominal surgery.
BACKGROUND: The optimal positive end-expiratory pressure (PEEP) to prevent postoperative pulmonary complications (PPCs) remains unclear. Recent evidence showed that driving pressure was closely related to PPCs. In this study, we tested the hypothesis that an individualized PEEP guided by minimum driving pressure during abdominal surgery would reduce the incidence of PPCs. METHODS: This single-centered, randomized controlled trial included a total of 148 patients scheduled for open upper abdominal surgery. Patients were randomly assigned to receive an individualized PEEP guided by minimum driving pressure or an empiric fixed PEEP of 6 cm H2O. The primary outcome was the incidence of clinically significant PPCs within the first 7 days after surgery, using a χ2 test. Secondary outcomes were the severity of PPCs, the area of atelectasis, and pleural effusion. Other outcomes, such as the incidence of different types of PPCs (including hypoxemia, atelectasis, pleural effusion, dyspnea, pneumonia, pneumothorax, and acute respiratory distress syndrome), intensive care unit (ICU) admission rate, length of hospital stay, and 30-day mortality were also explored. RESULTS: The median value of PEEP in the individualized group was 10 cm H2O. The incidence of clinically significant PPCs was significantly lower in the individualized PEEP group compared with that in the fixed PEEP group (26 of 67 [38.8%] vs 42 of 67 [62.7%], relative risk = 0.619, 95% confidence intervals, 0.435-0.881; P = .006). The overall severity of PPCs and the area of atelectasis were also significantly diminished in the individualized PEEP group. Higher respiratory compliance during surgery and improved intra- and postoperative oxygenation was observed in the individualized group. No significant differences were found in other outcomes between the 2 groups, such as ICU admission rate or 30-day mortality. CONCLUSIONS: The application of individualized PEEP based on minimum driving pressure may effectively decrease the severity of atelectasis, improve oxygenation, and reduce the incidence of clinically significant PPCs after open upper abdominal surgery.
Authors: Michiel T U Schuijt; Liselotte Hol; Sunny G Nijbroek; Sanchit Ahuja; David van Meenen; Guido Mazzinari; Sabrine Hemmes; Thomas Bluth; Lorenzo Ball; Marcelo Gama-de Abreu; Paolo Pelosi; Marcus J Schultz; Ary Serpa Neto Journal: EClinicalMedicine Date: 2022-04-16