0
Editorial |

The High Road, the Low Road, or Both: Effects of Positive Airway Pressure Route of Administration on Treatment Efficacy for OSA FREE TO VIEW

Nicholas J. Cutrufello, MD; Lee K. Brown, MD, FCCP
Author and Funding Information

FINANCIAL/NONFINANCIAL DISCLOSURES: The authors have reported to CHEST the following: L. K. B. has participated in advisory panels for Philips Respironics and is an insurance claims reviewer for Considine and Associates, Inc. He coedits the sleep and respiratory neurobiology section of Current Opinion in Pulmonary Medicine, wrote on CPAP treatment for obstructive sleep apnea in UpToDate and on obstructive sleep apnea in Clinical Decision Support: Pulmonary Medicine and Sleep Disorders. He is currently coediting an issue of Sleep Medicine Clinics on positive airway pressure therapy. He serves on the Polysomnography Practice Advisory Committee of the New Mexico Medical Board and chairs the New Mexico Respiratory Care Advisory Board. None declared (N.J.C).

aDivision of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM

bDepartment of Electrical and Computer Engineering, University of New Mexico School of Engineering, Albuquerque, NM

CORRESPONDENCE TO: Lee K. Brown, MD, FCCP, Department of Internal Medicine, School of Medicine; and School of Engineering, University of New Mexico, 1101 Medical Arts Ave NE, Bldg No. 2, Albuquerque, NM 87102


Copyright 2016, American College of Chest Physicians. All Rights Reserved.


Chest. 2016;150(6):1174-1176. doi:10.1016/j.chest.2016.09.031
Text Size: A A A
Published online

O ye'll tak' the high road, and I'll tak' the low road,And I'll be in Scotland afore ye,Traditional Scottish Song

When it comes to positive airway pressure (PAP) treatment for OSA, there has been surprisingly little debate concerning the relative efficacy of using the “high road” (nasal route) vs the “low road” (oral route). In the seminal report by Sullivan et al, the nasal route was chosen by reasoning that with the mouth outside of the circuit, a “safety valve” was present should the apparatus malfunction and overpressurize, and there would be an alternate breathing route should the nasal circuit occlude. Thus, nasal masks were the only available interfaces in the early days of continuous PAP (CPAP) until Sanders et al and Prosise and Berry reported the successful administration of CPAP through oronasal interfaces in 1994. Although Prosise and Berry did entertain the possibility that oronasal CPAP might fail to displace the tongue anteriorly, and therefore not adequately suppress obstruction, oronasal interfaces and a few oral-only interfaces soon appeared in the marketplace.

FOR RELATED ARTICLE SEE PAGE 1194

Most clinicians agree that “the best interface is the one that the patient will use.” Clinical guidelines for PAP titration (L. K. B. was a coauthor) incorporate a standard that “the patient should be carefully fitted for the interface (ie, nasal mask, nasal pillows, full-face/oronasal mask), with the goals of maximizing comfort, compensating for significant nasal obstruction, and minimizing leak prior to the PAP titration,” making no distinction between the different routes of administration. Choosing the right mask can often be of critical importance to achieving compliance, which is frequently established in the first week of treatment. Timely intervention if the interface is uncomfortable or leaks is of great importance in achieving early accommodation to PAP therapy; often the patient’s final interface is not the one used during laboratory titration. In general, clinicians have proceeded as if titration results remain valid regardless of subsequent changes in interface make, model, or size or route of administration. Yet, to what extent are we free to change interfaces and assume similar efficacy?

This question has not been ignored but also has not been settled. Meta-analyses by the Cochrane Collaboration and later by Andrade et al of published data concluded that oronasal CPAP is less effective than nasal CPAP (nCPAP). Andrade et al postulated mechanisms through which orally introduced PAP could affect critical closing pressure, resulting in the need for a different (usually higher) treatment pressure. Surprisingly, the Cochrane authors did not find oral-only CPAP to be inferior to nCPAP, and a physiological study by Smith et al found no differences in the pressure/flow relationships when CPAP was administered through the nasal vs the oral-only route.

In this issue of CHEST, Andrade et al report an elegant experiment in which they directly compared the effects of nasal, oronasal, and oral CPAP through direct visual airway inspection and respiratory monitoring. Eighteen obese adults (55% men) with a wide range of OSA severity were studied during daytime sleep induced by midazolam. CPAP was applied using a custom oronasal mask with pneumatically separate nasal and oral compartments that allowed application of CPAP exclusively through nasal, oral, or combined oronasal routes. During oronasal CPAP, flow monitors specific to each compartment recorded the amount of nasal vs oral breathing. Polysomnography confirmed sleep stage and recorded the presence of sleep-disordered breathing, and nasoendoscopy was used to visualize the retroglossal region. Initial titration with nCPAP determined an optimal effective pressure, which was then applied sequentially through the oronasal and oral routes for 2-min intervals of N2 sleep, totaling three sampling periods for each route. (Oral-only data could not be obtained in 16 subjects.) “Stable breathing” trials were identified when apnea and hypopnea were absent; if present, trials were categorized as exhibiting “unstable breathing.” Retroglossal and epiglottal areas, distances between the epiglottis and posterior pharyngeal wall, the tongue base, and epiglottis, and the lateral pharyngeal walls were measured from nasoendoscopic video recordings.

Of the 18 patients who achieved stable breathing on nCPAP, 12 experienced obstructive events while receiving oronasal CPAP, and unstable breathing occurred in every trial associated with < 50% of airflow through the nasal route. However, ≥ 50% nasal breathing did not invariably eliminate obstructive events, even in a few trials preceded by 100% nasal airflow. Of the 16 patients receiving oral CPAP, only two maintained stable breathing, whereas 14 experienced obstructive events. Uptitration to as high as 20 cm H2O was performed in 10 patients with unstable breathing while using the oronasal or oral route, or both. Two patients exhibited “flow limitation” at 20 cm H2O through the oronasal route, whereas oral CPAP failed in four subjects, and one patient was unable to sleep. Finally, the nasoendoscopic data demonstrated a reduction in the distance between the tongue base and epiglottis, as well as a diminished retroglossal area, when the CPAP route was changed from nasal (previously shown to achieve stable breathing) to oronasal or oral administration.

From these data, Andrade et al concluded that most patients with stable breathing established with nCPAP will experience obstructed breathing when the same pressure is delivered through the oronasal or oral routes and that this is associated with decreases in some airway dimensions. They hypothesized that airflow administered simultaneously through the nose and mouth reduces the pressure gradient between the nasopharynx and oropharynx, allowing gravity to displace the tongue and soft palate posteriorly. Oral-only CPAP could displace the tongue posteriorly with or without the effect of gravity. As an alternative explanation, mouth opening is known to adversely affect pharyngeal critical pressure, as shown previously in a study by Meurice et al of normal subjects.

This well-designed study addresses an important issue that has great relevance to the day-to-day practice of sleep medicine. Significant increases in pressure requirements may result when converting from a nasal to an oronasal or oral interface; moreover, increased levels of CPAP may not provide satisfactory control. Conversely, a patient who underwent titration using an oronasal or oral interface may require lower pressure if switched to nCPAP. One cautionary note: The generalizability of Andrade et al’s data may depend on the sleeping position maintained during the study, which was not specified. Nonsupine sleep may well yield different results compared with supine sleep because of the effects of gravity, and additional studies of this issue should be pursued.

Interrogation of most current PAP devices can provide an estimated apnea-hypopnea index (AHI), and careful attention to these estimates may be helpful if an oronasal or oral interface is substituted for a nasal appliance. Furthermore, autotitration settings may be advantageous over fixed pressures in patients who switch between different interfaces. Clearly, given the difficulty in establishing stable breathing in some of Andrade et al's subjects using pressures up to 20 cm H2O, this is a strategy that warrants careful investigation in future research. Finally, patients who remain or become symptomatic after an interface change, even if estimated AHI is normal, may require retitration in the sleep laboratory. The AHI reported by a PAP device is an estimate only, based on indirect measurement of airflow. This AHI may differ significantly from polysomnographic AHI, particularly with respect to hypopnea.,, Moreover, there is no consistent method by which these devices estimate AHI, and it has been recommended that these values be interpreted with caution. Finally, interface changes may yield other unintended consequences, such as the development of central sleep apnea.

References

Sullivan C.E. .Issa F.G. .Berthon-Jones M. .Eves L. . Reversal of obstructive sleep apnoea by continuous positive airway pressure applied through the nares. Lancet. 1981;1:862-865 [PubMed]journal. [PubMed]
 
Sanders M.H. .Kern N.B. .Stiller R.A. .Strollo P.J. Jr..Martin T.J. .Atwood C.W. Jr.. CPAP therapy via oronasal mask for obstructive sleep apnea. Chest. 1994;106:774-779 [PubMed]journal. [CrossRef] [PubMed]
 
Prosise G.L. .Berry R.B. . Oral-nasal continuous positive airway pressure as a treatment for obstructive sleep apnea. Chest. 1994;106:180-186 [PubMed]journal. [CrossRef] [PubMed]
 
Kushida C.A. .Chediak A. .Berry R.B. .et al Clinical guidelines for the manual titration of positive airway pressure in patients with obstructive sleep apnea. J Clin Sleep Med. 2008;4:157-171 [PubMed]journal. [PubMed]
 
Budhiraja R. .Parthasarathy S. .Drake C.L. .et al Early CPAP use identifies subsequent adherence to CPAP therapy. Sleep. 2007;30:320-324 [PubMed]journal. [PubMed]
 
Bachour A. .Vitikainen P. .Maasilta P. . Rates of initial acceptance of PAP masks and outcomes of mask switching. Sleep Breath. 2016;20:733-738 [PubMed]journal. [CrossRef] [PubMed]
 
Chai C.L. .Pathinathan A. .Smith B. . Continuous positive airway pressure delivery interfaces for obstructive sleep apnoea. Cochrane Database Syst Rev. 2006;:CD005308- [PubMed]journal
 
Andrade R.G. .Piccin V.S. .Nascimento J.A. .Viana F.M. .Genta P.R. .Lorenzi-Filho G. . Impact of the type of mask on the effectiveness of and adherence to continuous positive airway pressure treatment for obstructive sleep apnea. J Bras Pneumol. 2014;40:658-668 [PubMed]journal. [CrossRef] [PubMed]
 
Smith P.L. .O'Donnell C.P. .Allan L. .Schwartz A.R. . A physiologic comparison of nasal and oral positive airway pressure. Chest. 2003;123:689-694 [PubMed]journal. [CrossRef] [PubMed]
 
Andrade R.G.S. .Madeiro F. .Piccin V.S. .et al Impact of acute changes in CPAP flow route in sleep apnea treatment. Chest. 2016;150:1194-1201 [PubMed]journal. [CrossRef]
 
Meurice J.C. .Marc I. .Carrier G. .Sériès F. . Effects of mouth opening on upper airway collapsibility in normal sleeping subjects. Am J Respir Crit Care Med. 1996;153:255-259 [PubMed]journal. [CrossRef] [PubMed]
 
Brown L.K. . Adaptive servo-ventilation for sleep apnea: technology, titration protocols, and treatment efficacy. Sleep Med Clin. 2010;5:419-437 [PubMed]journal. [CrossRef]
 
Prasad B. .Carley D.W. .Herdegen J.J. . Continuous positive airway pressure device–based automated detection of obstructive sleep apnea compared to standard laboratory polysomnography. Sleep Breath. 2010;14:101-107 [PubMed]journal. [CrossRef] [PubMed]
 
Desai H. .Patel A. .Patel P. .Grant B.J. .Mador M.J. . Accuracy of autotitrating CPAP to estimate the residual apnea-hypopnea index in patients with obstructive sleep apnea on treatment with autotitrating CPAP. Sleep Breath. 2009;13:383-390 [PubMed]journal. [CrossRef] [PubMed]
 
Ueno K. .Kasai T. .Brewer G. .et al Evaluation of the apnea-hypopnea index determined by the S8 auto-CPAP, a continuous positive airway pressure device, in patients with obstructive sleep apnea-hypopnea syndrome. J Clin Sleep Med. 2010;6:146-151 [PubMed]journal. [PubMed]
 
Schwab R.J. .Badr S.M. .Epstein L.J. .Gay P.C. .et al An official American Thoracic Society statement: continuous positive airway pressure adherence tracking systems. The optimal monitoring strategies and outcome measures in adults. Am J Respir Crit Care Med. 2013;188:613-620 [PubMed]journal. [CrossRef] [PubMed]
 
Montesi S.B. .Bakker J.P. .Macdonald M. .et al Air leak during CPAP titration as a risk factor for central apnea. J Clin Sleep Med. 2013;9:1187-1191 [PubMed]journal. [PubMed]
 

Figures

Tables

References

Sullivan C.E. .Issa F.G. .Berthon-Jones M. .Eves L. . Reversal of obstructive sleep apnoea by continuous positive airway pressure applied through the nares. Lancet. 1981;1:862-865 [PubMed]journal. [PubMed]
 
Sanders M.H. .Kern N.B. .Stiller R.A. .Strollo P.J. Jr..Martin T.J. .Atwood C.W. Jr.. CPAP therapy via oronasal mask for obstructive sleep apnea. Chest. 1994;106:774-779 [PubMed]journal. [CrossRef] [PubMed]
 
Prosise G.L. .Berry R.B. . Oral-nasal continuous positive airway pressure as a treatment for obstructive sleep apnea. Chest. 1994;106:180-186 [PubMed]journal. [CrossRef] [PubMed]
 
Kushida C.A. .Chediak A. .Berry R.B. .et al Clinical guidelines for the manual titration of positive airway pressure in patients with obstructive sleep apnea. J Clin Sleep Med. 2008;4:157-171 [PubMed]journal. [PubMed]
 
Budhiraja R. .Parthasarathy S. .Drake C.L. .et al Early CPAP use identifies subsequent adherence to CPAP therapy. Sleep. 2007;30:320-324 [PubMed]journal. [PubMed]
 
Bachour A. .Vitikainen P. .Maasilta P. . Rates of initial acceptance of PAP masks and outcomes of mask switching. Sleep Breath. 2016;20:733-738 [PubMed]journal. [CrossRef] [PubMed]
 
Chai C.L. .Pathinathan A. .Smith B. . Continuous positive airway pressure delivery interfaces for obstructive sleep apnoea. Cochrane Database Syst Rev. 2006;:CD005308- [PubMed]journal
 
Andrade R.G. .Piccin V.S. .Nascimento J.A. .Viana F.M. .Genta P.R. .Lorenzi-Filho G. . Impact of the type of mask on the effectiveness of and adherence to continuous positive airway pressure treatment for obstructive sleep apnea. J Bras Pneumol. 2014;40:658-668 [PubMed]journal. [CrossRef] [PubMed]
 
Smith P.L. .O'Donnell C.P. .Allan L. .Schwartz A.R. . A physiologic comparison of nasal and oral positive airway pressure. Chest. 2003;123:689-694 [PubMed]journal. [CrossRef] [PubMed]
 
Andrade R.G.S. .Madeiro F. .Piccin V.S. .et al Impact of acute changes in CPAP flow route in sleep apnea treatment. Chest. 2016;150:1194-1201 [PubMed]journal. [CrossRef]
 
Meurice J.C. .Marc I. .Carrier G. .Sériès F. . Effects of mouth opening on upper airway collapsibility in normal sleeping subjects. Am J Respir Crit Care Med. 1996;153:255-259 [PubMed]journal. [CrossRef] [PubMed]
 
Brown L.K. . Adaptive servo-ventilation for sleep apnea: technology, titration protocols, and treatment efficacy. Sleep Med Clin. 2010;5:419-437 [PubMed]journal. [CrossRef]
 
Prasad B. .Carley D.W. .Herdegen J.J. . Continuous positive airway pressure device–based automated detection of obstructive sleep apnea compared to standard laboratory polysomnography. Sleep Breath. 2010;14:101-107 [PubMed]journal. [CrossRef] [PubMed]
 
Desai H. .Patel A. .Patel P. .Grant B.J. .Mador M.J. . Accuracy of autotitrating CPAP to estimate the residual apnea-hypopnea index in patients with obstructive sleep apnea on treatment with autotitrating CPAP. Sleep Breath. 2009;13:383-390 [PubMed]journal. [CrossRef] [PubMed]
 
Ueno K. .Kasai T. .Brewer G. .et al Evaluation of the apnea-hypopnea index determined by the S8 auto-CPAP, a continuous positive airway pressure device, in patients with obstructive sleep apnea-hypopnea syndrome. J Clin Sleep Med. 2010;6:146-151 [PubMed]journal. [PubMed]
 
Schwab R.J. .Badr S.M. .Epstein L.J. .Gay P.C. .et al An official American Thoracic Society statement: continuous positive airway pressure adherence tracking systems. The optimal monitoring strategies and outcome measures in adults. Am J Respir Crit Care Med. 2013;188:613-620 [PubMed]journal. [CrossRef] [PubMed]
 
Montesi S.B. .Bakker J.P. .Macdonald M. .et al Air leak during CPAP titration as a risk factor for central apnea. J Clin Sleep Med. 2013;9:1187-1191 [PubMed]journal. [PubMed]
 
NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543