Valve Study Shows Some Benefits and Some Risks
Over the past year, I have been asked by a few patients with COPD in my practice, “What else can you do to help my breathing get better?” Each of these individuals is taking available long-acting inhaled bronchodilators, is participating in pulmonary rehabilitation program, and is on oxygen.
In response to the question, I describe the possibility of a research study where a doctor passes a flexible scope thru the mouth and then into the breathing tubes to look inside the lungs (called bronchoscopy).
Umbrella-like valves are attached to the end of the scope and then placed into the breathing tubes to collapse part of the lung which is not functioning.This allows the “good lung” to expand and allows the diaphragm (the main breathing muscle) to work more effectively. Ideally, this will improve lung function and make it easier to breathe. The procedure is called bronchoscopic lung volume reduction.
Diagram of scope passed thru mouth into the lungs (called bronchoscopy)
Photo of umbrella device taken from inside a breathing tube. The umbrella will block air from entering the lung leading to collapse.
In the United States, this procedure is considered investigational which means additional studies are required to evaluate benefits and risks before approval by the Food and Drug Administration.
In June 2015, Dr. Davey and her colleagues published the results of a study (in the journal Lancet, volume 386) involving 50 patients with severe emphysema. In Group 1 (25 patients), valves were placed by a bronchoscope (a scope passed thru mouth into breathing tubes) to cause collapse of one lobe of the lung. Group 2 (25 patients) was considered as a control group as individuals had the same bronchoscope passed into the breathing tubes to mimic the first group, but no valves were place (sham or fake).
The study was performed at the Royal Brompton and Imperial College in London, United Kingdom, a leading respiratory research institute. The study was not sponsored by a commercial company.
The study had several very specific requirements for individuals to enter the study:
View of umbrella valves positioned into breathing tubes that block entry of air and collapse the lung
RESULTS at 3 months after procedure:
Outcome Group 1 Group 2 (control group) Signficant
Change in FEV1 + 8.8% + 2.9% Yes
Change in 6 min walk + 27 yards + 3 yards Yes
Change in exercise time on cycle + 25 sec – 11 sec Yes
Quality of life – 4.4 units – 3.6 units No
(the lower the score the better quality of life)
RISKS: Two patients in Group 1 died within 90 days of the procedure. One patient in Group 2 was too sick to return for follow-up testing. Two patients in Group 1 had a pneumothorax (air in the space around the lung due to rupture) which occurred at 3 days and at 12 days after the procedure). Both patients who had a pneumothorax needed a tube placed between the ribs in order to remove the air and allow the hole to heal. Four patients coughed out a valve before 3 months.
MY COMMENT: As often seen in studies, some individuals improved a lot after the procedure while others did not improve at all. Any treatment including placement of valves into the lung requires the individual to consider both benefits and possible risks. In the northeast, the closest research site in the study is Beth Isreal-Deaconess Medical Center in Boston.
- general emphysema with a lobe in one lung as a target to collapse (we all have 3 lobes in the right lung and 2 lobes in the left lung)
- an intact interlobar fissure on CT scan of the chest (this means that air should not be able to pass from an open lobe to the collapsed lobe after the valve has been placed)
- the key breathing test result – forced expiratory volume in one second (FEV1) – less than 50% of predicted
- low exercise capacity (unable to walk more than 450 meters (492 yards) in six minutes
- the need to stop because of shortness of breath after walking 100 yards or after a few minutes on the level