The risk of postoperative pulmonary complications in lung resection candidates with normal FEV₁and DL_CO: a prospective multicenter study

IntroductionAccording to the guidelines for preoperative assessment of lung resection candidates, patients with normal forced expiratory volume in the first second (FEV1) and diffusing capacity for carbon monoxide (DLCO) are at low risk for postoperative pulmonary complications (PPC). However, PPC affect hospital length of stay and related health care costs. We aimed to assess risk of PPC for lung resection candidates with normal FEV1and DLCO(>80% predicted) and identify factors associated with PPC.MethodsThree hundred and ninety-eight patients were prospectively studied at 2 centers between 2017 and 2021. PPC were recorded from the first 30 post-operative days. Subgroups of patients with and without PPC were compared and factors with significant difference were analyzed by uni- and multivariate logistic regression.ResultsOne hundred and eighty-eight subjects had normal FEV1and DLCO. Of these, 17 patients (9%) developed PPC. Patients with PPC had significantly lower pressure of end-tidal carbon dioxide (PETCO2) at rest (27.7versus29.9; p=0.033) and higher ventilatory efficiency (VE/VCO2) slope (31.1versus28; p=0.016) compared to those without PPC. Multivariate models showed association between rest PETCO2(OR 0.872; p=0.035) and VE/VCO2slope (OR 1.116; p=0.03) and PPC. In both models, thoracotomy was strongly associated with PPC (OR 6.419; p=0.005 and OR 5.884; p=0.007, respectively). Peak oxygen consumption failed to predict PPC (p=0.917).ConclusionsRest PETCO2adds incremental information for risk prediction of PPC in patients with normal FEV1and DLCO. We propose rest PETCO2be an additional parameter to FEV1and DLCOfor preoperative risk stratification.