Oxygen is used as a medical treatment in both chronic and acute cases, and can be used in hospital, pre-hospital or entirely out of hospital, dependent on the needs of the patient and their medical professionals' opinions.
oxygen to breathe either during a temporary worsening of their condition, or throughout the day and night. It is indicated in COPD patients with arterial oxygen partial pressure PaO 2 ≤ 55 mmHg (7.3 kPa) or arterial
oxygen saturation SaO 2 ≤ 88% and has been shown to increase lifespan.
