The technique of pursed lip breathing allow the patients to control the oxygenation and ventilation. This technique is performed by allowing the person to inspire through the nose exhale through the mouth at a slow controlled flow. This technique works by moving oxygen into your lungs and carbon dioxide out of your lungs. Pursed lip breathing (PLB) helps to slow down breathing rate and relieving shortness of breath by keeping the airways open longer. So patients can remove the air that is trapped in to the lungs.
In a recent systematic review that is published in 2018, PLB was shown to significantly improve ventilation related outcomes such as respiratory rate and minute ventilation, but not dyspnea and exercise capacity.
Diaphragmatic breathing (DB), that is also called deep breathing, this breathing is done by contracting the diaphragm, a muscle located horizontally between the thoracic cavity and abdominal cavity. During this type of breathing, air enters in to the lungs, the chest does not rise and belly expands. Diaphragmatic breathing encourages fully oxygen exchange, that is the beneficial trade of incoming oxygen for out going carbon dioxide.
