Monday, September 17, 2007

A Nasal Cannula Can Be Used to Treat Obstructive Sleep Apnea

A Nasal Cannula Can Be Used to Treat Obstructive Sleep Apnea

American Journal of Respiratory and Critical Care Medicine Vol 176. pp. 194-200, (2007)

Brian M. McGinley1, Susheel P. Patil1, Jason P. Kirkness1, Philip L. Smith1, Alan R. Schwartz1 and Hartmut Schneider1

1 Johns Hopkins Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland

Correspondence and requests for reprints should be addressed to Hartmut Schneider, M.D., Ph.D., Johns Hopkins Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Room 4B47, Baltimore, MD 21224. E-mail:

Rationale: Obstructive sleep apnea syndrome is due to upper airway obstruction and is associated with increased morbidity. Although continuous positive airway pressure efficaciously treats obstructive apneas and hypopneas, treatment is impeded by low adherence rates.

Objectives: To assess the efficacy on obstructive sleep apnea of a minimally intrusive method for delivering warm and humidified air through an open nasal cannula.

Methods: Eleven subjects (age, 49.7 ± 5.0 yr; body mass index, 30.5 ± 4.3 kg/m2), with obstructive apnea–hypopnea syndrome ranging from mild to severe (5 to 60 events/h), were administered warm and humidified air at 20 L/minute through an open nasal cannula.

Measurements and Main Results: Measurements were based on standard sleep-disordered breathing and arousal indices. In a subset of patients pharyngeal pressure and ventilation were assessed to determine the mechanism of action of treatment with nasal insufflation. Treatment with nasal insufflation reduced the mean apnea–hypopnea index from 28 ± 5 to 10 ± 3 events per hour (p < 0.01), and reduced the respiratory arousal index from 18 ± 2 to 8 ± 2 events per hour (p < 0.01). Treatment with nasal insufflation reduced the apnea–hypopnea index to fewer than 10 events per hour in 8 of 11 subjects, and to fewer than 5 events per hour in 4 subjects. The mechanism of action appears to be through an increase in end-expiratory pharyngeal pressure, which alleviated upper airway obstruction and improved ventilation.

Conclusions: Our findings demonstrate clinical proof of concept that a nasal cannula for insufflating high airflows can be used to treat a diverse group of patients with obstructive sleep apnea.


Scientific Knowledge on the SubjectHigh levels of continuous positive airway pressure (CPAP) are needed to alleviate obstructive apneas; low compliance with CPAP impedes its therapeutic effectiveness; and, because hypopneas can be treated with low levels of CPAP, nasal insufflation of air might effectively treat mild obstructive sleep apnea.

What This Study Adds to the FieldNasal insufflation can provide distinct clinical advantages over CPAP for a substantial proportion of the patient population with sleep apnea.

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