Effects of Alveolar Recruitment and Positive End-Expiratory Pressure on Oxygenation during One-Lung Ventilation in the Supine Position

Abstract

Purpose

Hypoxemia during one-lung ventilation (OLV) remains a serious problem, particularly in the supine position. We investigated the effects of alveolar recruitment (AR) and positive end-expiratory pressure (PEEP) on oxygenation during OLV in the supine position.

Materials and Methods

Ninety-nine patients were randomly allocated to one of the following three groups: a control group (ventilation with a tidal volume of 8 mL/kg), a PEEP group (the same ventilatory pattern with a PEEP of 8 cm H ₂O), or an AR group (an AR maneuver immediately before OLV followed by a PEEP of 8 cm H ₂O). The tidal volume was reduced to 6 mL/kg during OLV in all groups. Blood gas analyses, respiratory variables, and hemodynamic variables were recorded 15 min into TLV (TLV _baseline), 15 and 30 min after OLV (OLV ₁₅ and OLV ₃₀), and 10 min after re-establishing TLV (TLV _end).

Results

Ultimately, 92 patients were analyzed. In the AR group, the arterial oxygen tension was higher at TLV _end, and the physiologic dead space was lower at OLV ₁₅ and TLV _end than in the control group. The mean airway pressure and dynamic lung compliance were higher in the PEEP and AR groups than in the control group at OLV ₁₅, OLV ₃₀, and TLV _end. No significant differences in hemodynamic variables were found among the three groups throughout the study period.

Conclusion

Recruitment of both lungs with subsequent PEEP before OLV improved arterial oxygenation and ventilatory efficiency during video-assisted thoracic surgery requiring OLV in the supine position.