A Lower Tidal Volume Regimen during One-lung Ventilation for Lung Resection Surgery Is Not Associated with Reduced Postoperative Pulmonary Complications

Abstract

Background Protective ventilation may improve outcomes after major surgery. However, in the context of one-lung ventilation, such a strategy is incompletely defined. The authors hypothesized that a putative one-lung protective ventilation regimen would be independently associated with decreased odds of pulmonary complications after thoracic surgery. Methods The authors merged Society of Thoracic Surgeons Database and Multicenter Perioperative Outcomes Group intraoperative data for lung resection procedures using one-lung ventilation across five institutions from 2012 to 2016. They defined one-lung protective ventilation as the combination of both median tidal volume 5 ml/kg or lower predicted body weight and positive end-expiratory pressure 5 cm H2O or greater. The primary outcome was a composite of 30-day major postoperative pulmonary complications. Results A total of 3,232 cases were available for analysis. Tidal volumes decreased modestly during the study period (6.7 to 6.0 ml/kg; P < 0.001), and positive end-expiratory pressure increased from 4 to 5 cm H2O (P < 0.001). Despite increasing adoption of a “protective ventilation” strategy (5.7% in 2012 vs. 17.9% in 2016), the prevalence of pulmonary complications did not change significantly (11.4 to 15.7%; P = 0.147). In a propensity score matched cohort (381 matched pairs), protective ventilation (mean tidal volume 6.4 vs. 4.4 ml/kg) was not associated with a reduction in pulmonary complications (adjusted odds ratio, 0.86; 95% CI, 0.56 to 1.32). In an unmatched cohort, the authors were unable to define a specific alternative combination of positive end-expiratory pressure and tidal volume that was associated with decreased risk of pulmonary complications. Conclusions In this multicenter retrospective observational analysis of patients undergoing one-lung ventilation during thoracic surgery, the authors did not detect an independent association between a low tidal volume lung-protective ventilation regimen and a composite of postoperative pulmonary complications. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

Effect of Driving Pressure-Oriented Ventilation on Patients Undergoing One-Lung Ventilation During Thoracic Surgery: A Systematic Review and Meta-Analysis

“…In recent years, lung-protective ventilation (LPV), which aims to use low V T and PEEP with the recruitment maneuver to prevent PPCs. ( 21 , 22 , 24 , 25 ) However, low V T does not appear to be associated with lower PPC S ( 26 – 29 ). Moreover, individual characteristics, such as chest wall size and shape, abdominal contents, lung weight, and pleural pressure, vary from person to person, so a fixed PEEP may not be appropriate for everyone ( 30 ).…”

Driving pressure-guided ventilation and postoperative pulmonary complications in thoracic surgery: a multicentre randomised clinical trial

“…Whereas the association between driving pressure and mortality in ARDS appears linear, 14 this may not be the case for pulmonary complications in surgical patients. Previous retrospective studies have failed to identify a significant relationship between pulmonary complications and either driving pressure 10 or modified driving pressure (peak pressure minus PEEP) 12 after thoracic surgery. The relationship between pulmonary complications and driving pressure was non-linear in our study, and reached a plateau at a driving pressure of 9 cm H 2 O.…”

“…6,10,11 Furthermore, in a recent multicentre cohort study, adherence to a standard protective ventilation strategy was not associated with a decreased incidence of pulmonary complications in lung resection surgery. 12 Airway driving pressure, easily measured as plateau pressure minus PEEP, is a surrogate for alveolar stress and strain 13,14 and has an inverse relationship with static lung compliance. Airway driving pressure has emerged as the only ventilation parameter that is independently associated with adverse outcomes in ventilated patients; tidal volume, plateau pressure, and PEEP were not associated with pulmonary complications or mortality when they do not influence driving pressure in patients with acute respiratory distress syndrome (ARDS) 14e16 or in patients undergoing major surgery.…”

An optimal protective ventilation strategy in lung resection surgery: A prospective, single- center, 3-arm randomized controlled trial

“…There are some studies reporting that there is no signi cant difference in clinical variables between protective and conventional ventilation strategies. However, they were mostly observational cohort studies or randomized controlled trials conducted in humans without regulating other factors affecting protective ventilation strategy, such as PEEP, FiO 2 , or alveolar recruitment [26][27][28][29][30] .…”