Prediction of the postoperative pulmonary function and complication rate in elderly patients.

We analyzed the risk factors predisposing elderly patients to develop postoperative respiratory complications (PRCs) and investigated the possibility of predicting the postoperative pulmonary function and PRC rate. The postoperative pulmonary functions were predicted according to a simplified system, which we developed using plain chest roentgenograms from patients with primary lung cancer. Both univariate and multivariate analyses of PRCs were performed in 39 elderly patients with lung cancer from July 1982 to March 1991 (the early period). Based on the results obtained, the permissible extent of lung resection to achieve a predicted postoperative % forced expiratory volume in 1 s (ppo%FEV1.0) and a predicted postoperative % vital capacity (ppo%VC) of more than 55% was selected as the basic criteria for undergoing such an operation after April 1991 (the recent period). A ppo%FEV1.0 and/or ppo%VC of 55% or less was the most significant risk factor for developing PRCs. The PRC rate decreased from 33.3% to 9.8% (P = 0.0251) and the operative mortality rate decreased from 10.3% to 0%. The survival rates for stage I, II. and III cases were not significantly different between the early and recent periods. Decisions made on the operability and the permissible extent of lung resection based on our system using plain chest roentgenograms therefore appeared to reduce the PRC rate and operative mortality rate in elderly patients.