ORAL-NASAL CONTINUOUS POSITIVE AIRWAY PRESSURE AS A TREATMENT FOR OBSTRUCTIVE SLEEP-APNEA

The effect of continuous positive airway pressure (CPAP) applied via a mask covering the nose and mouth (oral-nasal CPAP=ONCPAP) on obstruct ive sleep apnea (OSA) was studied in ten male patients with a mean (+/ - SD) age of 48.1 +/- 11.1 years who could not tolerate nasal CPAP (NC PAP) due to nasal congestion. Using ONCPAP at pressures of 11.0 +/-, 4 .5 cm H2O, the apnea+hypopnea index was reduced from 58.3 +/- 22.3 (ba seline night) to 5.2 +/- 1.6 events per hour (ONCPAP night) (p<0.001). Five of these patients were studied on a subsequent night with a dual chamber mask allowing separate measurement of nasal and oral now. All patients had combined oral and nasal flow at times during the night, but the fraction of time spent with this breathing pattern was lower d uring sleep than wakefulness. In a separate study, we compared the eff ects of a therapeutic level of CPAP pressure (12.8 +/- 2.5 cm H2O) app lied through a nasal mask (NCPAP) and ONCPAP in a different group of p atients (mean age 60 +/- 14.6 years) with moderate to severe OSA using NCPAP on a long-term basis. The apnea-hypopnea indexes on NCPAP night s (7.2 +/- 3.5) and ONCPAP nights (7.6 +/- 4.9 events per hour of slee p) were very similar. We conclude that ONCPAP may be a reasonable trea tment alternative in patients who cannot tolerate NCPAP due to nasal c ongestion and that the pressure required to maintain upper airway pate ncy may be similar to the level required using NCPAP.