THE EFFECT OF NASAL CPAP ON NOCTURNAL REFLUX IN PATIENTS WITH APERISTALTIC ESOPHAGUS

It has been shown that nasal continuous positive airway pressure (nasa l CPAP) significantly reduces nocturnal reflux both in patients with s leep apnea and in patients without sleep apnea but consistent abnormal nocturnal reflux. The mechanism by which CPAP is thought to reduce re flux includes the elevation of the resting lower esophageal sphincter (LES) pressure. In this study, we tested the effect of nasal CPAP in t wo groups of patients with aperistaltic esophagus but with different r esting LES pressure. Seven patients with scleroderma esophagus and six patients treated for achalasia were tested over a 48-h period. On the first night, the patients were untreated; on the second night, both g roups received applied nasal CPAP at 8 cm H2O pressure. The percentage of time the pH <4.0, the number of reflux events >5 min, and the leng th of the longest reflux event were all significantly reduced in the p atients with achalasia (p<0.03), but not in the scleroderma group (p>0 .20). These results suggest that a residual resting LES pressure great er than that demonstrated by patients with scleroderma (>10 mm Hg) may be necessary for nasal CPAP to affect nocturnal reflux.