Abstract
BACKGROUND: Retrospective analyses have associated elevated mechanical power (MP) during one-lung ventilation (OLV) with reintubation rates and emergent non-invasive ventilation. Nonetheless, the study design and chosen outcomes may limit the generalizability of these findings to postoperative pulmonary complications (PPCs) in patients undergoing thoracoscopic lobectomy. The aim of this study was to evaluate whether this association remained robust under a standardized anesthesia protocol. METHOD: A prospective cohort study was conducted at a tertiary hospital among adults aged 50-80 years. Respiratory signals, chest computed tomography, and blood sampling were routinely measured. MP was defined as the sum of the energy transferred to overcome airway resistance and temporarily stored in the elastic lung tissue in one minute. The primary endpoint was the association of MP and PPCs. The secondary endpoints were the occurrence of impaired postoperative oxygenation, changes in lung aeration compartments, and systemic inflammatory factors during the perioperative period. RESULTS: Patient recruitment lasted from August 1st 2022 to July 19th 2024 and included 118 participants. The incidence of PPCs was 33.9 %. MP during OLV and normalization to lung volume in non-surgical lungs, as well as the elastic and resistive components of MP, were independently associated with PPCs (ORadj =1.67 [1.01, 2.76], p =0.044; 1.68 [1.04, 2.71], p =0.033; 1.81 [1.16, 3.11], p =0.046; and 2.61 [1.09, 6.27], p =0.031, respectively). Compared with resistive components, dynamic elastic component of MP had a stronger dominance on PPCs (contribution to pseudo-R2 0.029 vs. 0.015). The relationship between MP and PPCs was non-linear (p =0.047), with a reflection point at MP of 3.7 J.min-1. Compared to those without PPCs, patients with PPCs exhibited higher perioperative IL-10 levels and consistently poor lung aeration—both preoperatively in the non-dependent region and postoperatively in the mid-ventral region. Changes in biomarkers did not differ between patients; however, IL-8 levels showed consistent associations with PPCs during the perioperative observation period. CONCLUSION: Under lung-protective ventilation, MP during OLV was independently and non-linearly associated with PPCs, driven predominantly by its dynamic elastic component and accompanied by specific inflammatory and aeration changes. CLINICAL TRIAL REGISTRATION: Number ChiCTR2200062173 (restarted on July 27th 2022). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-026-03776-1.