Pursed-lips Breathing and Dynamic Hyperinflation
|ClinicalTrials.gov Identifier: NCT02203058|
Recruitment Status : Completed
First Posted : July 29, 2014
Last Update Posted : July 29, 2014
Background: Dynamic hyperinflation (DH) is an important factor leading to dyspnea and consequent limitations in functional capacity of chronic obstructive pulmonary disease (COPD) patients. It has not been completely elucidated whether pursed-lips breathing (PLB) is able to minimize DH and its effects on exercise tolerance in these patients. The aim of this study was to evaluate the acute effect of PLB on DH and functional capacity in patients with COPD.
Design: Randomized cross-over study. Setting: The study will be conducted in an outpatient pulmonary rehabilitation program in Florianópolis, Brazil.
Subjects: Twenty-five patients with COPD (16 men, mean age 64 (7) years, FEV1=41.7 (14.7)% predicted, BMI=27.6 (5.13)kg/m2).
Interventions: Patients will randomly perform two six-minute walk tests with and without PLB (6MWTPLB and 6MWTNon-PLB) and two Glittre-ADL tests with and without PLB (TGlittrePLB and TGlittreNon-PLB).
Main measures: At baseline and immediately after the tests, the inspiratory capacity (IC) will be assessed by the slow vital capacity (SVC) maneuver.
|Condition or disease||Intervention/treatment||Phase|
|Chronic Obstructive Pulmonary Disease||Other: Pursed-lips breathing Other: No pursed-lips breathing||Not Applicable|
Pulmonary function testing Lung function will be tested using an Easy One spirometer (NDD Medical Technologies Inc., Zurich, Switzerland), and calibration checked before each evaluation. Spirometry will be performed in accordance with ATS/ERS standards (Miller et al, 2005). The predicted values will be calculated from the equations proposed by Pereira et al. (2007).
Inspiratory capacity (IC) measurement IC will be measured with the patient in the sitting position, using an Easy One portable spirometer (NDD Medical Technologies Inc., Zurich, Switzerland), before and immediately after the tests, by the slow vital capacity maneuver starting from a stable end-expiratory volume, in accordance with ATS/ERS standards (Miller et al,2005). A minimum of three maneuvers (maximum of eight) will be performed and, in order to be considered reproducible, two curves could not vary by more than 5% or 150mL. The higher value of two reproducible curves will be used for analysis. DH is considered when the IC decreased 10% and/or 150mL or more compared to the basal value (O'Donnell et al, 2001).
Six-minute walk test The 6MWT will be performed according to the guidelines of the American Thoracic Society (2002). Pulse oxygen saturation (SpO2; Oxi-Go, Oximeter Plus, Roslyn Heights, New York, USA) and dyspnea (Borg CR10 scale) will be measured at the beginning and at the end of the test. Predicted values for walking distance will be calculated according to Iwama et al. (2009).
Glittre-ADL test The TGlittre consists of completing a circuit as follows: from a sitting position, the subject stands up and walks along a flat 10-m long course, in the middle of which there is a two-step ladder (each step 17 cm high x 27 cm deep) to be climbed; after completing the 10 m, the subject faces a shelf containing three 1-kg objects positioned on the top shelf (shoulder height) and moves them one by one to the bottom shelf (waist height) and then to the floor; the objects are then returned to the bottom shelf and finally to the top shelf again; the subject walks back, climbing up and down the steps, until reaching the starting point (chair), sits down and immediately begins the next lap. The subjects carry a weighted backpack (2.5 kg for women, 5.0 kg for men) and are instructed to complete five laps on this circuit as quickly as possible. SpO2 and dyspnea index (Borg CR10 scale) will be measured at the beginning of the test, at the end of each lap, and at the end of the test (Skumlien et al, 2006).
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||25 participants|
|Intervention Model:||Crossover Assignment|
|Masking:||None (Open Label)|
|Official Title:||Pursed-lips Breathing Reduces Reduces Dynamic Hyperinflation Induced by Activities of Daily Living Test in Patients With COPD|
|Study Start Date :||March 2012|
|Actual Primary Completion Date :||March 2013|
|Actual Study Completion Date :||July 2013|
Experimental: Pursed-lips breathing
All patients performed both tests (six-minute walk test and Glittre ADL test) with pursed-lips breathing.
Other: Pursed-lips breathing
Expiration with pursed-lips during functional capacity tests.
Placebo Comparator: No pursed-lips breathing
All patients performed both tests (six-minute walk test and Glittre ADL test) without pursed-lips breathing.
Other: No pursed-lips breathing
To avoid pursed-lips breathing, subjects use a a mouthpiece (2cm diameter X 2cm length) such as the one used in pulmonary functional tests.
- Dynamic hyperinflation [ Time Frame: At the beginning and immediately after de six-minute walk test and Glittre ADL test. ]Effect of pursed-lips breathing on inspiratory capacity during the six-minute walk test and Glittre-ADL test.
- Six-minute walk test performance [ Time Frame: Both tests (with and without pursed-lips breathing) will be held at least two days to one week apart. ]Effect of pursed-lips breathing on the distance walked (meters) during the six-minute walk test.
- Glittre-ADL test performance [ Time Frame: Both tests (with and without pursed-lips breathing) will be held at least two days to one week apart. ]Effect of pursed-lips breathing on the time spent (minutes) performing the Glittre-ADL tes.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02203058
|Núcleo de Aisstência, Ensino e Pesquisa em Reabilitação Pulmonar|
|Florianópolis, Santa Catarina, Brazil, 88080-350|
|Study Director:||Anamaria F Mayer, PhD||Universidade do Estado de Santa Catraina|