Pursed-lips breathing for improved oxygenation at altitude

Excerpt

Pursed-lips breathing (PLB) has repeatedly been shown to improve gas exchange with increased arterial oxygenation and saturation (SaO₂) and decreased arterial carbon dioxide levels mainly by promoting slow and deep breathing pattern [1]. These effects were observed in healthy subjects at low and high altitude and in patients with many forms of pulmonary edema and those with obstructive lung diseases as well. Several mechanisms, e.g. deep breathing, recruitment of terminal airspaces, and changes regarding the work of breathing, the ventilation-perfusion matching, the alveolar-capillary pressure difference, or hemodynamic conditions, may be differently important for the improvement of oxygenation and the relieve of symptoms under various conditions. …