ORLANDO, FL—A simple breathing technique that takes only minutes to learn can help most patients with amyotrophic lateral sclerosis (ALS) not only coug h more effectively but also swallow more safely. The technique, called “breath stacking,” has been known to improve cough for almost two decades. A new study has shown that it also increases the patient’s ability to protect the airway during swallowing, lowering the risk of aspiration and choking. “This is a very important approach to therapy that can make a big difference to our patients in terms of both quality of life and length of life,” said Robert G. Miller, MD, director of the Forbes Norris MDFA/ALS Research Clinic at California Pacifi c Medical Center in San Francisco, who was not involved in the study. “Unfortunately, relatively few neurologists are familiar with it.” Study investigator Stuart Cleary, PhD, assistant professor of speech pathology and audiology at the University of Alberta in Edmonton, described the fi ndings here at the ALS-MND Society meeting here in December. Breath stacking is meant to interrupt a cycle of poor airway maintenance that is typical in ALS. As breathing muscles weaken, the ability to cough is impaired, leading to accumulation of mucus plugs in the smaller airways. At the same time, poor airway protection during swallowing increases the risk of aspiration. The breath stacking maneuver is simple, Dr. Cleary explained. The patient uses a resuscitator bag equipped with a one-way valve and mouthpiece to take a series of breaths without exhaling, expanding the lungs beyond what he or she can accomplish with a single breath. The resulting stretching of the lungs and chest wall opens clogged airways and increases chest compliance, leading to reduced airway resistance to airfl ow. “This translates to improved lung volumes, higher peak cough fl ows and improved airway clearance,” he said. “As a swallowing therapist, I am interested in protecting the airway during mealtime,” Dr. Cleary said. Anecdotal reports from ALS centers in Canada, where the practice is somewhat more common, indicated the technique seemed to improve swallowing safety, so he set out to test that in a rigorous fashion. Dr. Cleary enrolled 29 ALS patients with a mean age of 65 years, a median ALS Functional Rating Scale score of 28 out of 48, a mean forced vital capacity (FVC) of 58 percent of predicted, and a mean peak cough fl ow (PCF) of 245 L/min. Participants performed fi ve trials of breath stacking, each separated by about 20 seconds. Respiratory and swallowing tests were performed before treatment, and at 15 and 30 minutes afterward. Patients served as their own controls, performing the same tests on different days without breath stacking. Consistent with previous studies, peak cough fl ow improved following breath stacking, rising approximately 50 L/min following treatment, an increase which lasted 30 minutes after treatment. The difference was signifi cant for both time points versus baseline and versus the control value. Dr. Cleary also found that breath stacking improved patients’ ability to perform other airway-clearing techniques, such as throat clearing and “hawking,” as well as the supraglottic swallowing maneuver, which consists of holding one’s breath while swallowing, closing the vocal cords and protecting the airway. The combined effect, Dr. Cleary said, is that for up to 30 minutes after breath stacking, ALS patients were better able to cough, to clear mucus or food stuck in throat, and to swallow safely.
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