Comparison between Conventional and Protective One-Lung Ventilation for Ventilator-Assisted Thoracic Surgery

Abstract

Recent papers suggest protective ventilation (PV) as a primary ventilation strategy during one-lung ventilation (OLV) to reduce postoperative pulmonary morbidity. However, data regarding the advantage of the PV strategy in patients with normal preoperative pulmonary function are inconsistent, especially in the case of minimally invasive thoracic surgery. Therefore we compared conventional OLV (V_T 10 ml/kg, FiO₂ 1.0, zero PEEP) to protective OLV (V_T 6 ml/kg, FiO₂ 0.5, PEEP 5 cmH₂O) in patients with normal preoperative pulmonary function tests undergoing video-assisted thoracic surgery. Oxygenation, respiratory mechanics, plasma interleukin-6 and malondialdehyde levels were measured at baseline, 15 and 60 minutes after OLV and 15 minutes after restoration of two-lung ventilation. P_aO₂ and P_aO₂/FiO₂ were higher in conventional OLV than in protective OLV (P P <0.05); however, the magnitudes of increase were not different between the groups. Postoperatively there were no differences in the number of patients with P_aO₂/FiO₂ <300 mmHg or abnormalities on chest radiography. Protective ventilation did not provide advantages over conventional ventilation for video-assisted thoracic surgery in this group of patients with normal lung function.