德国德累斯顿工业大学Marcelo Gama de Abreu研究组的一项最新研究发现，对于接受全麻手术的肥胖患者，术中采用高PEEP及肺复张的机械通气策略，与低PEEP策略相比，不能减少术后肺部并发症。 这一研究成果于2019年6月3日发表在国际顶尖学术期刊《美国医学会杂志》上。

在接受随机分组的2013名成年患者中，1976名 (98.2%) 患者完成临床试验（平均年龄，48.8 岁；1381名 [69.9%] 女性患者；1778名 [90.1%] 患者接受腹部手术）。在意向治疗分析中，高PEEP组989名患者中211名(21.3%)患者以及低PEEP组987名患者中233名患者(23.6%)满足主要预后终点（差异，−2.3% [95% CI, −5.9% to 1.4%]；风险比，0.93 [95% CI, 0.83 to 1.04]; P = .23）。在9项预先确定的次要预后终点中，高PEEP组与低PEEP组间6项指标无显著差异，3项指标具有显著差异，包括低氧血症患者比例降低（高PEEP组5.0% vs 低PEEP组13.6%；差异，−8.6% [95% CI, −11.1% to 6.1%]; P < .001）。

术中较高水平的呼气末正压(PEEP)和肺泡补充操作可改善接受手术的肥胖患者的呼吸功能，但对临床结果的影响尚不确定。

附：英文原文

Title: Effect of Intraoperative High Positive End-Expiratory Pressure (PEEP) With Recruitment Maneuvers vs Low PEEP on Postoperative Pulmonary Complications in Obese Patients

Author: Thomas Bluth, MD; Ary Serpa Neto, MD, MSc, PhD; Marcus J. Schultz, MD, PhD; Paolo Pelosi, MD, FERS; Marcelo Gama de Abreu, MD, MSc, PhD, DESA.

Issue&Volume:Vol 321, No. 23,2019

Abstract: Importance  An intraoperative higher level of positive end-expiratory positive pressure (PEEP) with alveolar recruitment maneuvers improves respiratory function in obese patients undergoing surgery, but the effect on clinical outcomes is uncertain.

Objective  To determine whether a higher level of PEEP with alveolar recruitment maneuvers decreases postoperative pulmonary complications in obese patients undergoing surgery compared with a lower level of PEEP.

Design, Setting, and Participants  Randomized clinical trial of 2013 adults with body mass indices of 35 or greater and substantial risk for postoperative pulmonary complications who were undergoing noncardiac, nonneurological surgery under general anesthesia. The trial was conducted at 77 sites in 23 countries from July 2014-February 2018; final follow-up: May 2018.

Interventions  Patients were randomized to the high level of PEEP group (n = 989), consisting of a PEEP level of 12 cm H2O with alveolar recruitment maneuvers (a stepwise increase of tidal volume and eventually PEEP) or to the low level of PEEP group (n = 987), consisting of a PEEP level of 4 cm H2O. All patients received volume-controlled ventilation with a tidal volume of 7 mL/kg of predicted body weight.

Main Outcomes and Measures  The primary outcome was a composite of pulmonary complications within the first 5 postoperative days, including respiratory failure, acute respiratory distress syndrome, bronchospasm, new pulmonary infiltrates, pulmonary infection, aspiration pneumonitis, pleural effusion, atelectasis, cardiopulmonary edema, and pneumothorax. Among the 9 prespecified secondary outcomes, 3 were intraoperative complications, including hypoxemia (oxygen desaturation with Spo2 ≤92% for >1 minute).

Results  Among 2013 adults who were randomized, 1976 (98.2%) completed the trial (mean age, 48.8 years; 1381 [69.9%] women; 1778 [90.1%] underwent abdominal operations). In the intention-to-treat analysis, the primary outcome occurred in 211 of 989 patients (21.3%) in the high level of PEEP group compared with 233 of 987 patients (23.6%) in the low level of PEEP group (difference, −2.3% [95% CI, −5.9% to 1.4%]; risk ratio, 0.93 [95% CI, 0.83 to 1.04]; P = .23). Among the 9 prespecified secondary outcomes, 6 were not significantly different between the high and low level of PEEP groups, and 3 were significantly different, including fewer patients with hypoxemia (5.0% in the high level of PEEP group vs 13.6% in the low level of PEEP group; difference, −8.6% [95% CI, −11.1% to 6.1%]; P < .001).

Conclusions and Relevance  Among obese patients undergoing surgery under general anesthesia, an intraoperative mechanical ventilation strategy with a higher level of PEEP and alveolar recruitment maneuvers, compared with a strategy with a lower level of PEEP, did not reduce postoperative pulmonary complications.

DOI: 10.1001/jama.2019.7505

Source: https://jamanetwork.com/journals/jama/fullarticle/2735541