However, "during the early developmental years, LVRS was performed at times in inappropriate patients or under suboptimal settings, and the ensuing variable results led to questions about the therapeutic value of the procedure," said Robert L. Berger, MD, Associate Clinical Professor of Surgery at Harvard Medical School in Boston.
In addition, the number of patients who could be considered as candidates for the surgery exceeded one million in the United States alone, and with each surgery costing ,30,000 to ,35,000, the procedure was implicated as an insupportable financial burden for the health care industry.Thus, health insurers, including Medicare, discontinued their coverage of the procedure,despite its apparent success. However, noted Dr. Berger, LVRS produced impressive results consistently in a carefully selected population of patients with advanced emphysema.
Thus, in response to the intense controversy generated by the denial of a presumably effective palliative treatment, several single-center, randomized clinical trials and the National Emphysema Treatment Trial (NETT),which had a patient population of 1,218,were undertaken to assess the effectiveness of LVRS.All of these trials, especially NETT, yielded valuable information regarding the use of LVRS, but more data are necessary for definitive conclusions.
The Canadian Lung Volume Reduction (CLVR) surgery study and the Overholt-Blue Cross Emphysema Surgery Trial (OBEST) are two independent, multicenter, randomized clinical trials that compared LVRS plus optimal medical therapy with medical treatment alone.Because the studies were nearly identical in design, patient characteristics, and outcomes, noted Dr. Berger
, their results were combined in order to get a larger series with more power.
These differences are attributed to prevailing health care practices in the two countries rather than to differences in patient characteristics or treatment factors, Dr. Berger
In the combined-cohort LVRS group, FEV1
increased by 28.8,, while total lung capacity and residual volume decreased by 12.4, and 24.3,, respectively.Pco2 decreased by 2.9 mm Hg, and Dlco rose by 1.11 mm/min/mm Hg at six months.
..."Several distinct categories of patients who would most likely benefit from LVRS at the present state of the art have been well defined," said Dr. Berger, who was the director of the OBEST study.
"In the case of LVRS, one must determine the worth of getting a bedridden person out of bed in order to enable him/her to walk, to become more active, and perhaps a working individual in society," said Dr. Berger
."It is well to remember that the economics of a therapeutic intervention usually apply to the larger universe and are irrelevant to the individual patient who is unable to perform simple daily chores because of a disabling illness.He/she cares much less about economics than about the promise of regaining function from a therapeutic intervention."
Advances in the surgical procedure could reduce both the risks and costs of LVRS."Indeed, several nonsurgical approaches are undergoing laboratory and early clinical testing," Dr. Berger
pointed out."These procedures, performed through a bronchoscope, involve placement of one-way valves, creating pathways in the airway system of the lung, or remodeling the lung through deployment of biologic agents that initiate shrinkage and volume reduction of the diseased lung tissue through scar formation."
If found to be safe and effective, he
continued, "these nonsurgical approaches could revolutionize the field of lung volume reduction for advanced emphysema."