Pursed lip breathing, called PLB, is a mainstay for people living with chronic obstructive pulmonary disease, or COPD. Exhalation looks almost like a kiss. Physicians at Ohio State University describe it like whistling or playing a flute. Exhaled air is forced through lips held together tightly, or pursed. This slows exhalation by creating resistance; inhalation is normal and unobstructed.
Breathing Patterns
If you have COPD, you have narrow, partly obstructed air passages inside your lungs. Breathing is difficult, but exhaling is harder than inhaling, prolonging exhalation and delaying the next inhalation, making you short of breath.
During exhalation your lungs become smaller to push air out. Your air passages also become smaller, and resistance to air flow becomes even higher. PLB builds up back-pressure inside your lungs and splints your airways open so air can move more freely. PLB helps you exhale more fully and quickly, giving you a more normal ratio of inhalation to exhalation and a more normal breathing pattern.
Breathing Mechanics
Dr. Brian Tiep, reporting in the Journal of Cardiopilmonary Rehabilitation & Prevention, describes PLB as a benefit to disturbed lung mechanics in COPD. COPD traps air in your lungs as it progresses over many years. Your chest expands toward a maximum inhalation position. Ribs are raised, shoulders are held high, and your diaphragm is pushed downward. Taking a deep breath is almost impossible and the mechanics of breathing become exhausting. PLB is helpful because it makes exhalation more efficient and relieves some of the stressed chest wall mechanics.
Lung Volumes
Nobody exhales completely. After a normal exhalation a volume of air stays in your lungs. That stale air, low in oxygen and high in carbon dioxide, dilutes the fresh air you inhale on your next breath. So at its best even normal breathing is inefficient in healthy lungs. But in COPD the over-inflation creates an even bigger volume of stale air you can't exhale. PLB widens your airways and helps you exhale a larger volume of stale air to make more room for new, fresh air.
Oxygen and Carbon Dioxide Exchange
Your lungs absorb oxygen from air you inhale and replaces it with carbon dioxide to exhale. In COPD, trapped air becomes a reservoir for carbon dioxide while your body absorbs more and more oxygen out of it. The proportion of fresh air inhaled relative to the stale air already filling your lungs is too small to replenish the oxygen or eliminate the carbon dioxide fully. Your blood then carries too little oxygen and too much carbon dioxide, an unhealthy imbalance. PLB helps restore the right proportion of fresh air inhaled to stale air in your lungs.
Shortness of Breath
Physicians at the Cleveland Clinic say PLB is one of the most effective ways to relieve shortness of breath. By exhaling more fully, PLB relieves some of the trapped air in your lungs. Rib cage, diaphragm, and neck and shoulder stress is somewhat relieved, and your breathing becomes more efficient. Combined with higher oxygen and lower carbon dioxide levels, shortness of breath is relieved by PLB.
