EARLY AND LONG-TERM FUNCTIONAL OUTCOMES FOLLOWING LUNG VOLUME REDUCTION SURGERY

In the 3 years since an abstract was presented at the annual meeting of the American Society of Thoracic Surgeons, accompanied by a press release, lung volume reduction surgery (LVRS) has become the most controversial topic in the clinical management of patients with emphysema. 4,18,55,100 The procedure, which can be performed using several surgical approaches, entails the resection of 20% to 30% of the diseased lung in patients with diffuse emphysema and has been shown to, among other things, elicit short-term increases in expiratory flow and reduction in thoracic hyperinflation. The widespread execution of the procedure prior to peer-reviewed documentation and long-term follow-up, however, had been viewed cynically by many in the medical community. 18,100 In response to the concerns and a subsequent analysis by the Agency for Health Care Policy and Research, 46 Medicare has chosen to deny reimbursement for the procedure, pending the outcome of a National Institutes of Health (NIH)-supported clinical trial. In recent months, an increasing body of literature has contributed to the understanding of the procedure, although important issues remain incompletely defined: Which outcome parameters are most appropriate to balance the benefits and the risks of surgery? Which surgical approach optimizes benefits and minimizes risk? What is the time course of improvement following surgery compared with an identical control group? Which clinical, physiologic, and radiologic parameters define patients at highest risk or with greatest potential to benefit? Are those parameters similar for short- and long-term benefit? What are the mechanisms of improvement? What level of improvement warrants the expense of the procedure? Is the response to surgery in similar patients identical across institutions? Should surgery be performed in patients with disease characterized by uniform versus heterogeneous parenchymal involvement? This article emphasizes functional and basic physiologic changes that occur following LVRS in patients with emphysema. Whenever possible, peer-reviewed literature is emphasized but, because this is a rapidly evolving technology with much data in review or in press, the authors have relied to some extent on published abstracts and case examples to represent current knowledge and trends in the field. Admittedly, some of the information discussed, which reflects the author's best judgment, may ultimately be disproved.