Patient can safely undergo major lung resection without increased risk of post operative complications if:

Pulmonary Function Test: Pulmonary function studies are routinely performed when any resection greater than a wedge resection will be performed. Of all the measurement available, the two most valuables are FEV1 and DLCO. For every 10% decline in patients DLCO, the risk of any pulmonary complication (as estimated by Odd ratio) increased by 42%. patients with FEV1>2.0L can tolerate pneumonectomy, and those with an FEV1 of >1.5 L can tolerate lobectomy. Ref: Bailey 27th edition Pgno: 916-917