Although the predicted postoperative FEV1 is the best parameter in predicting postoperative complications after resection, its limitations are that it is unreliable in predicting outcomes among patients whose preoperative FEV1 is >70%, and it is most accurate in predicting lung function 3 to 6 months after a lobectomy [270]. The post-lobectomy FEV1 may be more than 30% lower than the predicted value during the first days to weeks postoperatively.