Using this procedure, published reports have indicated benefits in some patients. LVRS downsizes the lungs by resecting badly diseased emphysematous tissue that is functionally useless. During the course of surgery, one lung is continually ventilated while the lumen of the contralateral lung is clamped. Subsequently, normal areas of lung deflate as blood flows past the alveoli and resorbs oxygen, while emphysematous portions of the lung with less blood flow and reduced surface area remain inflated and are targeted for resection. LVRS is believed to improve function of the lung by restoring pulmonary elastic recoil and correcting over-distention of the thorax and depression of the diaphragm.
Some patients experience better respiratory mechanics and relief from severe dyspnea .
The reported benefits of LVRS in some patients include improved airflow, functional capacity and quality of life. It is unclear which patients benefit most from the surgery. As in any major thoracic procedure, there are risks. Despite optimistic reports, the morbidity, mortality and financial costs associated with LVRS appear to be high, indicating the need for further studies of both short and long term outcomes to truly evaluate the efficacy of LVRS and which patients it benefits the most. The National Emphysema Treatment Trial fills this need.