Inspiratory Capacity as an Indirect Measure of Immediate Effects of Positive Expiratory Pressure and CPAP Breathing on Functional Residual Capacity in Healthy Subjects

CPAP and EPAP elicit similar lung deflation in a non‐equivalent mode in GOLD 3‐4 COPD patients

“…After testing for parametric distribution using the Shapiro‐Wilk method, only SpO 2 was log‐transformed to calculate repeated measure two‐way ANOVA tests with t ‐Student comparisons and Bonferroni corrections, with a significance level adjusted to 5%. A PASS software program (PASS.NCSS, LLC, Kaysville, Utah) was used to calculate the sample, simulating a paired analysis based on a previous study . For a maximal arbitrary mean difference of IC between CPAP and EPAP of 3% and a standard deviation of ±5% (two‐sided), a minimum sample of 22 patients was calculated, with a power of 0.803 at the level of α = 0.05.…”

“…A couple of studies have demonstrated that there are patients with a potential to hyperinflation and others to deflation of the lungs with both on CPAP and off CPAP, depending not only on the pressure level studied but also the phenotype of COPD . Both on CPAP and on EPAP can decrease IC in healthy subjects, and sequential IC measures are considered reliable to measure acute lung volume changes both in the laboratory and in primary care …”

Interpretation of Pulmonary Function Tests: Beyond the Basics

“…Although it has been studied mostly in COPD, investigators have found usefulness of IF in other settings as well, including the assessment of therapeutic response to continuous positive airway pressure (CPAP), 58 or in the setting of pulmonary arterial hypertension, where IC was found to be a more useful predictor of survival than the IF. 59 Despite its usefulness, the fact that the IF provides more information on prognosis than in diagnosis has likely limited its use in routine practice, though the number of available studies supporting its value, particularly in emphysema, certainly argue for more frequent use.…”

A drinking straw as an alternative device for creating positive expiratory pressure in people who have undergone thoracic surgery

“…PEP devices are commonly used in physiotherapy 9 . Clinicians often use some alternative devices to create PEP, such as water bottles (bubble-PEP device) or gloves 10,11 , when the access to a classic PEP device either is not available or not easy due to limited resources or other practical reasons.…”

“…Several studies have already investigated alternative devices that create PEP during exhalation by using simple tubes either sunk in the water 10,12 or not 13 , of various tube diameters 14 , with proven therapeutic effect 15,16 .…”