Weight Gain After Lung Volume Reduction Surgery Is Not Correlated With Improvement in Pulmonary Mechanics: Materials and Methods

23 Sep

Preoperative Evaluation for LVRS
All patients underwent a detailed history and physical examination. Spirometry and lung volume measurements were performed with a calibrated pneumotachograph (Medical Graphics Co; St. Paul, MN) and values were expressed as a percent of the predicted values published by Morris et al. Lung volumes were measured in a whole body plethysmograph and the data expressed as a percent of predicted values.
Chest imaging was obtained as previously reported. Dobut-amine echocardiography was routinely performed to screen for cardiac disease. If right ventricular function appeared compromised or if pulmonary hypertension was suspected, a right-heart catheterization was performed. Similarly, if left ventricular wall motion abnormalities were noted during dobutamine infusion, a left-heart catheterization was performed. comments

All patients undergoing LVRS were required to complete > 6 weeks of intensive pulmonary rehabilitation. Programs emphasized education and exercise training, with the latter including both lower and upper extremity conditioning. The preoperative target for successful rehabilitation was the ability to exercise on a treadmill at 1 to 1.5 miles per hour on the level, for a continuous 30-min period. The pulmonary function data shown were obtained following completion of pulmonary rehabilitation. Patients were encouraged but not required to reenter pulmonary rehabilitation after surgery.
Surgical techniques for study patients included either median sternotomy with bilateral apical lung volume reduction utilizing a linear stapler buttressed with strips of bovine pericardium, or bilateral lower lobe reduction via muscle-sparing thoracotomies. The location and volume of tissue to be resected was guided by findings from the chest imaging studies, which delineated those areas involved with severe emphysematous change receiving minimal, if any, perfusion.