NASAL CONTINUOUS POSITIVE AIRWAY PRESSURE - A NEW TREATMENT FOR NOCTURNAL GASTROESOPHAGEAL REFLUX

Nasal continuous positive airway pressure (CPAP) reduces nocturnal gas troesophageal reflux (GER) in obstructive sleep apnea syndrome (OSAS) patients. The primary objectives of our investigation were to determin e if CPAP could reduce reflux in non-OSAS patients and, if so, by what mechanism. Esophageal pH was monitored for 48 h in six nocturnal refl ux patients. During the first 24 h, basal reflux data were collected; the second night, nasal CPAP was administered (pressure = 8 cm H2O). E sophageal manometry was obtained in six healthy adult volunteers both on and off nasal CPAP (pressure = 8 cm H2O) to ascertain CPAP's effect s on esophageal pressure and peristalsis. The six reflux patients expe rienced less nocturnal GER while on CPAP. The mean percent time esopha geal pH < 4 was reduced from 27.7 +/- 10.0 to 5.8 +/- 2.6 (p < 0.004); the mean reflux duration dropped from 2.1 +/- 0.6 to 0.9 +/- 0.5 min (p < 0.03); and the mean duration of longest reflux improved from 84.3 +/- 32.6 to 13.8 +/- 6.9 min (p < 0.01). The CPAP raised the mean res ting midesophageal pressure by 4.4 cm H2O (p < 0.01) and the mean rest ing lower esophageal pressure (LES) by 13.2 cm H2O (P < 0.02) in the h ealthy volunteers. Nasal CPAP effectively reduced nocturnal GER in six patients with nocturnal reflux. The antireflux activity of CPAP is li kely due to passive elevation of intraesophageal pressure and possibly to reflex LES constriction.