Indications for long-term oxygen therapy for COPD - McMaster Textbook of Internal Medicine

Table 21.15-1. Indications for long-term oxygen therapy for COPD
PaO2	SpO2 or SaO2	Indications
≤55 mm Hg	≤88%	Always
55-59 mm Hg	88%-89%	If one of these is present: – Cor pulmonale – Pulmonary hypertension – Persistent erythrocytosis (hematocrit >55%)
≥60 mm Hg	≥90%	If one of these occurs: – Exercise limited by hypoxemia (SpO2 <88%) – Nocturnal hypoxemia
Based on Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease: 2020 Report. www.goldcopd.org
COPD, chronic obstructive pulmonary disease; PaO2, partial pressure of oxygen in arterial blood; SaO2, direct measurement of hemoglobin oxygen saturation in arterial blood; SpO2, measurement of hemoglobin oxygen saturation in arterial blood using pulse oximetry.