Oxygen Therapy in COPD.

Long-term oxygen therapy (LTOT) at home has been demonstrated to improve survival in patients with COPD and severe resting hypoxemia. Support for LTOT is based on 2 landmark trials published nearly 4 decades ago. These results form the basis for reimbursement and prescription of LTOT to this day. Recent work has demonstrated no outcome benefit of LTOT in stable COPD patients with moderate desaturation at rest or during activity. Oxygen therapy during activity and exercise has been shown to alleviate symptoms and maintain arterial oxygen saturation, but not improve long-term outcomes. Oxygen therapy in COPD has a number of physiologic, functional, and biologic effects, not all of which are completely understood. Oxygen therapy in exacerbations of COPD can be both helpful and harmful. New guidance on the use of oxygen therapy during pre-hospital care has been published in the United Kingdom. Technology for LTOT represents a challenge for physicians writing prescriptions, durable medical equipment suppliers, caregivers, and patients. New technology for automated control of LTOT shows promise but is hampered by regulatory processes and cost pressures. Recent changes in government reimbursement for home oxygen therapy also present challenges. This paper will review the current evidence regarding LTOT in COPD and the impact on mortality and functional outcomes as well as reviewing technological challenges.