Chest ACCP Education Calendar
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Guest Access | Sign In via User Name/Password
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow View responses
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Article Archive
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via ISI Web of Science (1)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Spicuzza, L.
Right arrow Articles by Di Maria, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Spicuzza, L.
Right arrow Articles by Di Maria, G.
(Chest. 2006;130:774-779.)
© 2006 American College of Chest Physicians

Effect of Treatment With Nasal Continuous Positive Airway Pressure on Ventilatory Response to Hypoxia and Hypercapnia in Patients With Sleep Apnea Syndrome*

Lucia Spicuzza, MD, PhD, FCCP; Luciano Bernardi, MD; Rossella Balsamo, MD; Nicola Ciancio, MD; Riccardo Polosa, MD, PhD and Giuseppe Di Maria, MD, FCCP

* From Dipartimento di Medicina Interna e Medicina Specialistica (Drs. Spicuzza, Balsamo, Polosa, and Di Maria), Sezione di Malattie Respiratorie, Università di Catania, Catania; Unità Operativa di Clinica Pneumologica e Medicina Respiratoria del Sonno (Dr. Ciancio), Azienda Ospedaliera Garibaldi, Catania; and Dipartimento di Medicina Interna e Patologia (Dr. Bernardi), IRCCS S. Matteo, Università di Pavia, Pavia, Italy.

Correspondence to: Lucia Spicuzza, MD, Dipartimento di Medicina Interna e Medicina Specialistica, Sezione di Malattie Respiratorie, Via Passo Gravina 187, 95125 Catania, Italy; e-mail: luciaspicuzza{at}tiscali.it

Abstract

Background: The increase in peripheral chemoreflex sensitivity in patients with obstructive sleep apnea (OSA) is associated with activation of autonomic nervous system and hemodynamic responses. Nasal CPAP (nCPAP) is an effective treatment for OSA, but little is known on its effect on chemoreflex sensitivity.

Objectives: To assess the effect of nCPAP treatment or placebo (sham nCPAP) on ventilatory control in patients with OSA.

Setting: Sleep laboratory of Azienda Ospedaliera Garibaldi.

Patients: Twenty-five patients with moderate-to-severe OSA.

Design and measurements: Patients were randomly assigned to either therapeutic nCPAP (use of optimal pressure, n = 15) or sham nCPAP (suboptimal pressure of 1 to 2 cm H2O, n = 10) in a double-blind fashion and treated for 1 month. A rebreathing test to assess ventilatory response to normocapnic hypoxia and normoxic hypercapnia was performed at basal condition and after 1 month of treatment.

Results: The use of therapeutic nCPAP or sham nCPAP did not affect daytime percentage of arterial oxygen saturation (SaO2%) or end-tidal PCO2. The normocapnic hypoxic ventilatory response was reduced after 1 month of treatment with nCPAP (the slope was 1.08 ± 0.02 L/min/SaO2% at basal condition and 0.53 ± 0.07 L/min/SaO2% after 1 month of treatment, p = 0.008) [mean ± SD], but not in patients treated with sham nCPAP (slope, 0.83 ± 0.09 L/min/SaO2% and 0.85 ± 0.19 L/min/SaO2% at basal condition and after 1 month, respectively). The normoxic hypercapnic ventilatory response remained unchanged after 1 month in both groups. No changes in ventilatory response to either hypoxia or hypercapnia were observed after a single night of nCPAP treatment.

Conclusion: The ventilatory response to hypoxia is reduced during regular treatment, but not after short-term treatment, with nCPAP. Readjusted peripheral oxygen chemosensitivity during nCPAP treatment may be a side effect of both reduced sympathetic activity and increased baroreflex activity, or a possible continuous positive airway pressure-related mechanism leading to a reduced activation of autonomic nervous system per se.

Key Words: hypercapnia • hypoxia • nasal continuous positive airway pressure • obstructive sleep apnea • ventilatory response




eLetters:

Read all eLetters

Untitled
Rosa D Grembiale, et al.
Chest Online, 16 Mar 2007 [Full text]

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2006 by the American College of Chest Physicians.