Determinants of prediction of post-operative lung function in patients undergoing surgical lobectomy

Aim: to evaluate contribution of both CT-virtual lobectomy and anatomic compute in prediction of post-operative FEV1 (poFEV1). Methods: 31 NSCLC (15 COPD) patients, candidate for surgical lobectomy, underwent lung function tests and CT-scan. CT resected and total lung volumes, without (RLV, TLV) and with emphysema extent correction (RLVe, TLVe), number of resected segments and pre-operative FEV1 (preFEV1) were considered to estimate predicted post-operative FEV1 (ppoFEV1). We adopted general formula: ppoFEV1= preFEV1 x [1-(resected volume/total volume)] in both anatomic and radiological computing. Radiological and anatomic methods were performed and the resulting values were compared with poFEV1. Results: Linear regression analysis of poFEV1 showed significative relationships with ppoFEV1 estimated by anatomic method (R2:0,73) and different radiological approaches considering: RLVe and TLVe (R2:0,75); RLVe and TLV (R2:0,76); RLV and TLV (R2:0,79). Multiple regression analysis considering patients with airflow obstruction (FEV1/FVC < 70%) and the numbers of days occurring between surgery and first post-resection functional evaluation (VISITIME) showed: - anatomic method: R2:0,82; - RLVe and TLVe: R2:0,81; - RLVe and TLV: R2:0,82; - RLV and TLV: R2:0,81. Conclusions: anatomic and radiological methods to estimate poFEV1 show similar results. Predictive power for poFEV1 of all methods ameliorates considering VISITIME and airflow obstruction.