Noninvasive nasal mask-assisted ventilation in respiratory failure of Duchenne muscular dystrophy.

The effects of noninvasive nasal mask-assisted ventilation were studied in two patients with chronic respiratory failure due to Duchenne's muscular dystrophy. Observations were made with continuous recordings of transcutaneous CO2 and O2 and ear oximetry. In one case, the mean tcPCO2 fell from 72 mm Hg to 43 mm Hg. The tcPO2 increased from 38 mm Hg to 62 mm Hg without supplementary oxygen. In the second case, hypercapnia associated with supplementary oxygen was corrected, and at five months' follow-up, hypoxemia was corrected without supplementary oxygen. Prolonged therapy during sleep has resulted in sustained clinical improvement for more than 18 months.