Indications for continuous long-term oxygen therapy (LTOT) for patients with chronic lung disease include (table 1):
•Resting arterial oxygen tension (PaO2) less than or equal to 55 mmHg (7.32 kPa), or a pulse oxygen saturation (SpO2) less than or equal to 88 percent
•PaO2 less than or equal to 59 mmHg (7.85 kPa), or an SpO2 less than or equal to 89 percent, if there is evidence of cor pulmonale, right heart failure, or erythrocytosis (hematocrit >55 percent)
•PaO2 of 59 mmHg (7.85 kPa) or lower, or an SpO2 of 88 percent or lower, during exercise or sleep may benefit from administration of supplemental oxygen during those times, although the evidence for benefit is less clear
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