MORE COPD PATIENTS COULD BENEFIT FROM OXYGEN THERAPY

MORE COPD PATIENTS COULD BENEFIT FROM OXYGEN THERAPY

The website 6-minutes, a daily newsletter for Australian doctors, reports on a study that finds many patients ineligible for supplemental oxygen under current criteria could still benefit from oxygen therapy. They conclude that a single daytime measurement of oxygen in the blood may not be the best method of determining who could benefit from oxygen therapy. Researchers find a large number of people are okay during the day, but have oxygen saturations below 90 percent at night. For more information, see:

More COPD patients could benefit from oxygen

Many COPD patients with borderline hypoxaemia would benefit from long term oxygen therapy but are currently excluded due to misleading one-off measurements of oxygenation, Victorian researchers say.

A study of 35 COPD patients with moderate hypoxaemia on resting showed that 24-hour oximetry was able to identify a large subgroup of patients who had clinically significant hypoxaemia throughout the day and especially at night.

The use of ambulatory oximetry showed that 54% of patients spent more than 30% of the monitoring period with oxygen saturation below 90%, “suggesting a significant degree of hypoxaemia that is often missed by point measurement of PaO2,” say the researchers from Barwon Health in the Internal Medicine Journal (online 1 December) .

“We believe this group may include patients with the potential to benefit from this therapy [despite] being ineligible for prescription of long term oxygen therapy according to current criteria,” they write.

The study authors say long term oxygen therapy is known to improve survival, pulmonary dynamics and exercise capacity in patients with severe hypoxaemia, but currently eligibility for oxygen therapy is decided by point measurement of PaO2.

The study also showed that BMI was correlated with daytime hypoxaemia, whereas age and PaO2 were the only significant predictors of nocturnal hypoxaemia.

“Our findings suggest that a single daytime measurement of resting PaO2 may not be the optimal method for determining which patients will benefit from this approach to nocturnal oxygen prescription,” they say.

By Michael Woodhead