We have recently experienced with 3 cases of bilateral lung volume reduction surgery (LVRS) in patients with severe emphysematous disease in an effort to improve pulmonary mechanics. We compared intraoperative total dynamic lung compliance (CT) and % of breath exhaled in one second (V1.0%) obtained immediately pre-lung reduction and immediate post-lung reduction. In addition we also compared preoperative pulmonary function test (PFT) [FEV1, TLC, TG (trapped gas) and FRC] with 3 month postoperative values. Two of the three patients demonstrated post-reduction improvement in dynamic CT while only one patient demonstrated post-reduction improvement in V1.0%. All three patients demonstrated an increase in FEV1 and a decrease in TLC, TG and FRC with the greatest change in one patient who also had a significant reduction in CT and an improvement in V1.0% intraoperatively, and post-lung reduction. Although our results of the 3 cases are preliminary, it appears that side stream spirometry with immediate intraoperative measurement of dynamic CT and V1.0% could play a role in predicting expected follow-up objective pulmonary function tests; improvement in both CT and V1.0% may predict significant improvements in PFT.