Effect of Stepwise Lung Recruitment Maneuver on Oxygenation, Lung Mechanics and Lung Injury Biomarkers During Lung Resection Surgery: A Prospective Randomized Controlled Single Blinded Study

Abstract

Background: One lung ventilation for lung resection surgery may affect oxygenation, impair lung mechanics and increase the incidence of acute lung injury. Lung recruitment maneuver may improve these conditions. Settings and Design: This study was a prospective randomized controlled single blinded clinical trial. Methods: Forty patients scheduled for elective lung resection surgeries using one lung ventilation under general anaesthesia were randomly allocated into two groups. Control (C) group was subjected to conventional mechanical ventilation of tidal volume of 8 ml/kg and 5 ml/kg for total lung ventilation (TLV) and one lung ventilation (OLV), respectively, and PEEP of 5 cmH2O and (LR) group which was subjected to stepwise lung recruitment twice: The first lung recruitment (LR1) was performed after (OLV) to the dependent lung, while the second lung recruitment (LR2) was performed after resuming (TLV). Arterial blood gases, lung mechanics and serum tumor necrosis factor alpha were recorded at multiple time points during the study. The proposal and raw data were registered on PACTR as PACTR202001518687696. Results: There was a significant decrease in PaO2/FIO2 during OLV baseline in comparison to TLV baseline (P = < 0.001*) in both groups. While, in LR group, there was a significant increase in PaO2/FIO2 and dynamic compliance during OLV-20 min after recruitment (P = <0.001*), during TLV-20 min after recruitment (P = < 0.001*) and during TLV-end (P = <0.001*). TNF-⍺ level was significantly higher in control group 1 h after surgery and 24 h postoperative. Conclusion: Stepwise lung recruitment maneuver improved oxygenation parameters and lung mechanics during lung resection surgery and decreased the expression of lung injury biomarkers. Abbreviations: OLV: one lung ventilation; TLV: total lung ventilation; RM: recruitment maneuver; LR: lung recruitment; TNF-⍺: tumor necrosis factor alpha; VCV: volume controlled ventilation; PCV: pressure controlled ventilation; VT: tidal volume; FIO2: fraction of inspired oxygen; ALI: acute lung injury; ppoFEV1%: predicted postoperative forced expiratory volume in 1 s; BAL: Bronchoalveolar lavage.