Chronic Obstructive Lung Disease - Oxygen-Replacement Therapy

Oxygen-Replacement Therapy

Eventually, lung function may worsen to the point that patients may need to rely on supplemental oxygen provided through portable or stationary tanks.

Continuous Therapy. Continuous oxygen therapy (more than 15 hours a day) is the only treatment for emphysema that has been proven to prolong survival in certain patients. It also improves alertness, motor speed, and hand strength. Usually continuous oxygen therapy is recommended for patients under the following circumstances:

• Lung oxygen level is below 55 mm/Hg while the patient is resting.
• Resting oxygen level is less than 60 mm/Hg, and the patient has right heart failure or an abnormal increase in red blood cells.

The patient should receive enough oxygen to keep the oxygen level at 65 mm/Hg ideally, but at no less than 60 mm/Hg, or at an oxygen saturation level of at least 90%. Additional oxygen flow may be needed during sleep or exertion (physical activity).

About 40% of patients improve enough in 1 month to stop continuous treatment, although such patients should be observed closely. COLD frequently deteriorates, requiring reinstitution of oxygen therapy. Some patients worsen in spite of treatment, although at this point it is not possible to predict who is at risk for oxygen therapy failure. The addition of nitric oxide, a gas that dilates blood vessels, may offer additional benefits.

Intermittent Oxygen. Patients with less severe COLD who are not on permanent oxygen maintenance may need supplemental oxygen during specific circumstances:

• Patients whose oxygen level drops below 55 mm/Hg only while exercising may benefit from supplemental oxygen during physical activity. Supplemental oxygen does not necessarily improve exercise performance, but it does enhance delivery of oxygen to the muscles while they are working.
• Oxygen may be needed at night for patients whose oxygen level drops below 55 mm/Hg during sleep. Such patients usually experience fitful, poor-quality sleep. This type of oxygen therapy does not appear to affect survival or to delay prescription of continuous oxygen therapy.