The Potential Dangers of Recruitment Maneuvers During One Lung Ventilation Surgery

Abstract

Background: Existing evidence regarding lung-protective ventilation (LPV) during one-lung ventilation (OLV) focuses on surrogate outcomes. Our objective was to assess whether an LPV protocol during OLV surgery is associated with reduced respiratory complications.

Materials and methods: This was a matched control retrospective cohort study of patients undergoing pulmonary resection at a tertiary Canadian hospital. The experimental group (n = 50) was derived from primary data of two crossover RCTs, which utilized protocolized LPV strategies with varying levels of positive end-expiratory pressure and recruitment maneuvers. The control group was drawn from a prospectively maintained database; these patients received conventional nonprotocolized ventilation (2000-2010). Each experimental group patient was matched 1:1 with a control group patient with respect to clinically relevant variables (age, sex, diagnosis, smoking status, cardiovascular disease status, comorbidity, BMI, preoperative forced expiratory volume in 1 s, surgery type). Major respiratory complications were defined as composite of acute respiratory distress syndrome, need for new positive-pressure ventilation, and atelectasis requiring bronchoscopy. Paired and unpaired statistical tests were used.

Results: Patients appeared well matched. Major respiratory complications occurred in 8% (n = 4) and 2% (n = 1) of patients in experimental and control groups, respectively (P = 0.50). There was a trend toward increased mortality (4 versus 0, P = 0.06) with protocolized LPV. The patients who died had respiratory complications; one had acute respiratory distress syndrome and two had profound hypoxemia.

Conclusions: There was a nonsignificant trend toward increased mortality with LPV during OLV. Although limited by a small sample size, our findings identify a potential danger to excessive recruitment maneuvers. Larger studies, with clinically important outcomes are needed to better define the risk/benefit trade-offs for LPV during OLV.

Keywords: Lung-protective ventilation; One-lung ventilation; Pulmonary resection; Respiratory complications; Thoracic anesthesia.