Premium
Flow–volume curve changes in patients with obstructive sleep apnoea and brief upper airway dysfunction
Author(s) -
Campbell Alastair H,
Guy Paul A,
Rochford Peter D,
Worsnop Christopher J,
Pierce Robert J
Publication year - 2000
Publication title -
respirology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 85
eISSN - 1440-1843
pISSN - 1323-7799
DOI - 10.1046/j.1440-1843.2000.00220.x
Subject(s) - medicine , airway , confounding , body mass index , cardiology , area under the curve , volume (thermodynamics) , peak flow meter , exhalation , anesthesia , asthma , physics , quantum mechanics
Objective : Patients with obstructive sleep apnoea (OSA) and those with brief upper airway dysfunction (BUAD) have been reported to have abnormalities of maximal flow–volume curves. This study was designed to assess the ability of flow–volume curves to predict the presence of OSA or BUAD. Methodology : Four maximal flow–volume manoeuvres performed by 33 OSA patients and 16 BUAD patients were compared with those of 36 normal subjects. Flow–volume indices, their variability, saw‐toothing in the curve and an algorithm based on the flow ratios and shape of the curves were assessed. Results : When the confounding factors, body mass index (BMI), age, gender and smoking status were taken into account, there was no significant difference in a variety of indices derived from the flow–volume curves between OSA and normal subjects. No BUAD patient had normal flow–volume curves as determined with the algorithm. After BMI, age, gender and smoking status were accounted for, decreased forced expiratory volume in 1 s (FEV 1 ), and increased variability of peak expiratory flow (PEF)/peak inspiratory flow (PIF) and FEV 1 /PEF remained significantly associated with BUAD. Conclusions : These findings suggest that flow–volume curve indices have no value in predicting OSA. Some abnormalities are found in patients with BUAD; a normal flow–volume curve makes the diagnosis of BUAD unlikely.