<prompt> Patient can safely undergo major lung resection without increased risk of post operative complications if:FEV1 1L, Normal DLCOFEV1 1L, Decreased DLCOFEV1 2L, Normal DLCOFEV12L, Decreased DLCO  <response>: 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 FEV12.0L can tolerate pneumonectomy, and those with an FEV1 of 1.5 L can tolerate lobectomy. Ref: Bailey 27th edition Pgno: 916-917 