Air leak during CPAP titration as a risk factor for central apnea.

Abstract

OBJECTIVES:

Emergence of central sleep apnea has been described in the setting of continuous positive airway pressure (CPAP) initiation. The underlying mechanism is unclear; however, we postulate that air leak washing out anatomical dead space is a contributing factor.

DESIGN:

Data were obtained from 310 patients with obstructive sleep apnea (OSA) who underwent either split-night or full-night CPAP titration during January to July of 2009. The majority (n = 245) underwent titration with a nasal mask. Average total leak and maximum total leak were measured at therapeutic CPAP level. Unintentional leak was calculated by subtracting manufacturer-defined intentional leak from maximum leak.

RESULTS:

SUBJECTS WERE DIVIDED INTO TWO GROUPS: central apnea index (CAI) during titration < 5/hour and ≥ 5/hour. The groups were similar in terms of gender, age, BMI, and AHI. The CAI < 5 group had a median average leak of 45.5 L/min (IQR 20.8 L/min) versus 51.0 L/min (IQR 21.0 L/min) with CAI ≥ 5 (p = 0.056). Maximum leak was 59.5 L/min (IQR 27.0 L/min) with CAI < 5 and 75.0 L/min (IQR 27.8 L/min) with CAI ≥ 5 (p = 0.003). In the subset of subjects titrated using a nasal mask, median average leak was 42.0 L/min (IQR 17.0) in the CAI < 5 group and 50.0 L/min (IQR 16.8) in the CAI ≥ 5 group (p = 0.001). In the CAI < 5 group, median maximum leak was 57.0 L/min (IQR 23.0) versus 74.5 L/min (IQR 24.3) in the CAI ≥ 5 group (p < 0.001).

CONCLUSIONS:

Leak during CPAP titration is associated with the development of acute central apnea; these data may have mechanistic and therapeutic implications for complex apnea.

COMMENTARY:

A commentary on this article appears in this issue on page 1193.

• Authors: Sydney B Montesi, Jessie P Bakker, Mary Macdonald, Lauren Hueser, Stephen Pittman, David P White, Atul Malhotra
• Journal: Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine (J Clin Sleep Med) Vol. 9 Issue 11 Pg. 1187-91 (Nov 15 2013) ISSN: 1550-9397 [Electronic] United States
• PMID: 24235901 (Publication Type: Journal Article)

Topics

• Continuous Positive Airway Pressure (instrumentation, methods)
• Electroencephalography (methods)
• Female
• Humans
• Male
• Masks (adverse effects)
• Middle Aged
• Polysomnography (methods)
• Risk Factors
• Sleep Apnea, Central (etiology)
• Sleep Apnea, Obstructive (therapy)