# Variation in and deviation from protective ventilation during lung surgery

## TL;DR

This study examines how ventilation strategies during lung surgery vary and how they relate to postoperative complications.

## Contribution

The study identifies low adherence to protective ventilation guidelines and links high peak inspiratory pressure to increased complications.

## Key findings

- Only 7.5% of surgeries adhered to low tidal volume guidelines during OLV.
- Higher peak inspiratory pressure was associated with increased postoperative pulmonary complications.
- Longer duration of one-lung ventilation also increased complication risk.

## Abstract

One-lung ventilation (OLV) is used for most lung resections. Protective ventilation strategies aim to limit volutrauma, atelectrauma, and barotrauma to reduce postoperative pulmonary complications (PPCs). We aimed to describe patterns in ventilatory strategies used during OLV, identify factors that affect these strategies, and investigate their relationship with PPCs.

Consecutive eligible patients undergoing lung surgery at a tertiary thoracic center were enrolled in this prospective cohort study. Real-time data capture of intraoperative ventilation parameters was performed. Complications were assessed prospectively using the validated Ottawa Thoracic Morbidity and Mortality classification system. Univariate statistics were described regarding adherence to low tidal volume (VT), airway pressures, and positive end-expiratory pressure (PEEP). Multivariable regression models interrogated the relationships between PPCs (outcome variable), patient factors, and ventilatory parameters (predictor variables).

A total of 225 patients were included. The median VT, PEEP, driving pressure, and plateau pressure were 6.4 mL/kg, 5 cmH2O, 9.5 cmH2O, and 15.3 cmH2O, respectively. The percentage of surgeries within defined protective limits (VT < 5 mL/kg, PEEP ≥5 cmH2O, driving pressure ≤15 cmH2O, and plateau pressure ≤25 cmH2O) at least 75% of the OLV time were 7.5%, 86.7%, 67.4%, and 55.8%, respectively. An increased proportion of time with peak inspiratory pressure >25 cmH2O (odds ratio [OR], 3.62; 95% confidence interval [CI], 1.15-12.03; P = .0302) and duration of OLV (OR, 3.44; 95% CI, 1.88-6.65; P = .00011) were associated with PPCs.

Adherence to lung-protective ventilation recommendations was low. Higher peak inspiratory pressure is associated with PPCs, supporting barotrauma during OLV as a culprit. This is a target for quality assessment and knowledge translation efforts.