Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 1
pubmed:dateCreated
1991-1-17
pubmed:abstractText
Because flow-volume loops (FVLs) are clinically useful in evaluating upper airway (UA) obstruction and the fact that patency of the nasopharyngeal ventilatory pathway is important to the prevention of obstructive sleep apnea (OSA), the present study examined the role of nasal compared with oral FVLs in evaluating patients with OSA. Fourteen obese male patients 56 +/- 3 yr of age with a mean apnea plus hypopnea index (AHI) of 51 +/- 9/h were studied along with 14 nonobese, healthy, age- and sex-matched control subjects whose mean AHI was 6 +/- 1/h. Nasal and oral FVLs obtained in the normal subjects indicated the nose behaved like a variable resistor, with flow limitation during inspiration but not during expiration. In the patient group, flow limitation was observed during expiration as well as inspiration indicating nondistensibility of the nasopharyngeal ventilatory pathway in the patients compared to the control subjects. A change in body position from upright to supine in the OSA group was associated with small reductions in expiratory but not inspiratory flow rates. The area under the nasal supine flow-volume loop (FVLANaSup) was found to be highly correlated with awake resting PaO2 (r = 0.80) and PaCO2 (r = -0.83) in the patient group. In addition, multiple linear regression analysis revealed that PaO2 and the area under the nasal FVLs independently contributed to the prediction of AHI with a multiple R of 0.89. These results suggest that limitations to ventilation via the nasopharynx may significantly influence both gas exchange and the frequency of sleep-disordered breathing in patients with OSA.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0003-0805
pubmed:author
pubmed:issnType
Print
pubmed:volume
142
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1288-93
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Nasal and oral flow-volume loops in normal subjects and patients with obstructive sleep apnea.
pubmed:affiliation
Mayo Sleep Disorders Center, Mayo Clinic, Rochester, Minnesota 55905.
pubmed:publicationType
Journal Article, Clinical Trial, Comparative Study, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't