Assessment of airflow obstruction during CPAP by means of forced oscillation in patients with sleep apnea

The forced oscillation technique (FOT) is a noninvasive method to measure respiratory resistance (Rrs) potentially useful for monitoring upper airway obstruction in patients with obstructive sleep apnea/hypopnea syndrome (SAHS). The aim of this work was to test the clinical suitability of FOT in assessing dynamic changes in airflow obstruction in patients with SAHS during continuous positive airway pressure (CPAP) and to investigate the CPAP dependence of Rrs. Forced oscillation (5 Hz) was applied to six male patients with SAHS submitted to CPAP titration procedure. Esophageal pressure was measured with a balloon-tipped catheter. Mid-inspiratory resistance (Rrs,i), mid-expiratory resistance (Rrs,e), and esophageal pressure swings (deltaPes) were computed for the respiratory events recorded at each CPAP level. Rrs,i decreased markedly and significantly from 36.0 +/- 4.0 cm H2O x s/L (mean +/- SEM) at baseline CPAP (4 cm H2O) to 13.1 +/- 2.8 cm H2O x s/L at optimal CPAP (11.3 +/- 0.4 cm H2O). Rrs,e showed a faster decrease with increasing CPAP reaching normal values at approximately 8 cm H2O. Rrs,i was strongly correlated (r2 = 0.94) with deltaPes. Our results suggest that FOT can be used as an alternative to the esophageal balloon for assessing airflow obstruction in patients with SAHS and for CPAP titration. Moreover, FOT allows us to detect phasic changes in resistance within the breathing cycle.

Medienart:

Artikel

Erscheinungsjahr:

1998

Erschienen:

1998

Enthalten in:

Zur Gesamtaufnahme - volume:157

Enthalten in:

American journal of respiratory and critical care medicine - 157(1998), 5 Pt 1 vom: 23. Mai, Seite 1526-30

Sprache:

Englisch

Beteiligte Personen:

Navajas, D [VerfasserIn]
Farré, R [VerfasserIn]
Rotger, M [VerfasserIn]
Badia, R [VerfasserIn]
Puig-de-Morales, M [VerfasserIn]
Montserrat, J M [VerfasserIn]

Themen:

Journal Article
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 16.06.1998

Date Revised 15.11.2006

published: Print

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM095436618