In many cases of advanced emphysema — a chronic, progressive lung condition that interferes with breathing — reducing the size of the lungs by surgically removing lobes from both sides has been shown to improve both survival and quality of life. But some emphysema patients can’t tolerate this bilateral operation.
Now a study conducted by researchers at Washington University School of Medicine in St. Louis and the University of Pennsylvania Health System has shown that unilateral, or one-sided, lung volume reduction surgery has significant benefits for some emphysema patients, offering help to those who are not candidates for the bilateral surgery.
The researchers described their work in January at the 42nd annual meeting of the Society of Thoracic Surgeons, a not-for-profit educational organization representing more than 4,800 chest surgeons worldwide.
“A certain subset of emphysema patients are poor candidates for bilateral surgery,” says Bryan Meyers, M.D., associate professor of surgery. “Patients who have scarring on one side of their chest from past surgery, patients with coexisting heart conditions and the small segment of patients whose emphysema affects only one side of their lungs — these are all candidates for a unilateral lung volume reduction procedure.”
The presentation at the annual meeting discussed outcomes for 49 emphysema patients who underwent unilateral lung volume reduction surgery at the School of Medicine and Barnes-Jewish Hospital. After the procedure, the patients on average had over 30 percent increased lung function as measured by how much air they could blow out with a vigorous breath in one second. Although the improvement in function gradually decreased, as expected with this incurable and progressive disease, the benefits lasted at least three years for the average patient.
Tests also showed that the unilateral surgery patients had lower amounts of air left in the lung after exhalation, indicating they could exhale more thoroughly. This improvement also gradually decreased but lasted at least five years for the average patient.
In addition, requirements for supplemental oxygen declined substantially after the operation.
“We saw not only a functional benefit but also a survival benefit from the unilateral surgery,” Meyers says. “After three years, 83 percent of the patients who had the unilateral procedure were still alive and after five years, 55 percent had survived. That’s a significant increase in survival rate compared to emphysema patients who don’t have surgery.”
Survival for patients who had the unilateral procedure was the same as for a similar group of patients who had the bilateral procedure, and a national trial of lung volume reduction surgery clearly demonstrated that the bilateral procedure increases survival.
The current bilateral lung volume reduction procedure was pioneered at the School of Medicine in 1993 to treat end-stage emphysema. Removal of 20 percent to 30 percent of the lung on each side allows the remaining, less-diseased portion of the lung to function better, giving patients an improved quality of life.
“Try taking a deep breath and then another breath without exhaling the first, and you’ll get a feel for what happens in emphysema,” Meyers says. “The lungs of emphysema patients are maximally expanded because the lung’s air sacs have lost their elasticity and can’t push air out. With the expansion of the lungs and chest, the patients don’t have much ability to move air back and forth. But we found if we remove part of the lungs, we make it possible for the ribs and diaphragm to return to a more normal position, and it becomes easier for the patients to breathe.”
Early reported successes led to the lung volume reduction procedure’s rapid spread, but concerns about the safety and effectiveness led to a systematic evaluation of patient selection criteria and long-term outcomes in the National Emphysema Treatment Trial (NETT), which ran from 1996 to 2002.
Excluding patients at high risk of dying after surgery or with little chance of functional benefit, NETT researchers found that on average, patients with severe emphysema who undergo lung volume reduction are more likely to function better and don’t face an increased risk of death compared to those who receive only medical therapy. Overall, patients who had the surgery were more likely than those who were treated only medically to improve in function, symptoms and quality of life.
“As the result of NETT, Medicare now pays for bilateral lung volume reduction surgery for qualified emphysema patients,” Meyers says. “But they need more data on the efficacy of the unilateral procedure before they will approve coverage, and we believe this study helps provide that.”
Sultan PK, Meyers BF, Guthrie TJ, Davis GE, Yusen RD, Lefrak SS, Patterson GA, Cooper JD. Unilateral lung volume reduction: Long-term outcome in 49 emphysema patients. Presented at the 42nd annual meeting of the Society of Thoracic Surgeons. January 2006.
Funding from the National Institutes of Health supported this research.
Washington University School of Medicine’s full-time and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s