Intraoperative ventilation strategies to prevent postoperative pulmonary complications: a network meta-analysis of randomised controlled trials

• Published in: British journal of anaesthesia : BJA Vol. 124; no. 3; p. 324
• Main Authors: Deng, Qi-Wen, Tan, Wen-Cheng, Zhao, Bing-Cheng, Wen, Shi-Hong, Shen, Jian-Tong, Xu, Miao
• Format: Journal Article
• Language: English
• Published: England 01-03-2020
• Subjects: Bayes Theorem; Humans; Lung Diseases - etiology; Lung Diseases - prevention & control; Pneumonia - etiology; Pneumonia - prevention & control; Positive-Pressure Respiration - methods; Postoperative Complications - prevention & control; Pulmonary Atelectasis - etiology; Pulmonary Atelectasis - prevention & control; Randomized Controlled Trials as Topic - methods; Respiration, Artificial - adverse effects; Respiration, Artificial - methods; Respiratory Distress Syndrome, Adult - etiology; Respiratory Distress Syndrome, Adult - prevention & control; Tidal Volume; positive end-expiratory pressure; mechanical ventilation; ventilation; pulmonary complications; recruitment manoeuvre; tidal volume; surgery
• ISSN: 1471-6771
• DOI: 10.1016/j.bja.2019.10.024

The debate on lung-protective ventilation strategies for surgical patients is ongoing. Evidence suggests that the use of low tidal volume V
improves clinical outcomes. However, the optimal levels of PEEP and recruitment manoeuvre (RM) strategies incorporated into low V
ventilation remain unclear.
Several electronic databases were searched to identify RCTs that focused on comparison between low V
strategy and conventional mechanical ventilation (CMV), or between two different low V
strategies in surgical patients. The primary outcome was postoperative pulmonary complications (PPCs). The secondary outcomes were atelectasis, pneumonia, acute respiratory distress syndrome, and short-term mortality. Bayesian network meta-analyses were performed using WinBUGS. The odds ratios (ORs) and corresponding 95% credible intervals (CrIs) were estimated.
Compared with CMV, low V
ventilation with moderate-to-high PEEP reduced the risk of PPCs (moderate PEEP [5-8 cm H
O]: OR 0.50 [95% CrI: 0.28, 0.89]; moderate PEEP+RMs: 0.39 [0.19, 0.78]; and high PEEP [≥9 cm H
O]+RMs: 0.34 [0.14, 0.79]). Low V
ventilation with moderate-to-high PEEP and RMs also specifically reduced the risk of atelectasis compared with CMV (moderate PEEP+RMs: OR 0.36 [95% CrI: 0.16, 0.87]; and high PEEP+RMs: 0.41 [0.15, 0.97]), whilst low V
ventilation with moderate PEEP was superior to CMV in reducing the risk of pneumonia (OR 0.46 [95% CrI: 0.15, 0.94]).
The combination of low V
ventilation and moderate-to-high PEEP (≥5 cm H
O) seems to confer lung protection in surgical patients undergoing general anaesthesia.
PROSPERO (CRD42019144561).