IMT in Ventilatory Muscle Metaboreflex in COPD

Not Applicable

Completed

• Conditions: Chronic Obstructive Pulmonary Disease
• Interventions: Other: SHAM; Other: Inspiratory Muscle Training

• Registration Number: NCT01945398
• Lead Sponsor: Federal University of Rio Grande do Sul

Brief Summary

This research intends to evaluate if inspiratory muscle training (IMT) reduces inspiratory muscle metaboreflex through the decrease of calf vascular resistance and increase of calf blood flow in Chronic Obstructive Pulmonary Disease (COPD).

Detailed Description

Patients will be selected from the Hospital de Clinicas de Porto Alegre's COPD ambulatory, by convenience. Afterwards, patients will be submitted to pulmonary function test (spirometry) and cardiopulmonary exercise tests (incremental and submaximal), maximal inspiratory pressure evaluation and induction of the inspiratory muscle metaboreflex through venous occlusion plethysmography. Disease specific health related quality of life questionnaire (Saint George Respiratory Questionnaire) and daily life dyspnea questionnaire (Baseline Dyspnea Index and Transitional Dyspnea Index) will be administered at the first and last visit of each subject. Patients will undergo inspiratory muscle training for 30 minutes per day, 7 times a week, for 8 weeks, with Inspiratory Muscle Trainer device (PowerBreath Inc.). There will be a weekly follow up at the institution's Clinical Research Center, where maximal inspiratory pressure (PImax) and inspiratory training techniques will be reevaluated. After this period, tests of pulmonary function, questionnaires exercise tolerance and induction of the inspiratory muscle metaboreflex will be reevaluated.

Study Timeline

• Study Start: 2013-06
• Study First Submitted: 2013-09-15
• Study First Submitted QC: 2013-09-17
• Study First Posted: 2013-09-18
• Primary Completion: 2015-02
• Study Completion: 2015-02
• Status Verified: 2015-12
• Last Update Submitted: 2015-12-02
• Last Update Posted: 2015-12-03

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 13

Inclusion Criteria

Selection of subjects will be made through the Hospital de Clinicas de Porto Alegre Pneumology Service's COPD ambulatory. The inclusion criteria consist of -patients with COPD with functional confirmation through spirometry as by previously defined criteria.

Those selected must be classified as GOLD II-IV, with moderate to severe expiratory flow obstruction.

Exclusion Criteria

Patients will be considered ineligible for this study if they

• develop COPD exacerbation 8 weeks prior to recruitment
• if systemic corticosteroids are utilized (in the last three months)
• if there is history of acute myocardial infarction (in the last three months)
• if there is presence of neuromuscular disease
• history of cardiovascular disease or active smoking (in the last 6 months)
• clinical history of peripheral vascular disease and if age is equal or superior to 85 years

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Sham IMT	SHAM	Patients in the placebo group will be submitted to inspiratory muscle training with the same equipment as the intervention group, however without a resistance generating spring.
Inspiratory Muscle Training (IMT)	Inspiratory Muscle Training	Patients from the inspiratory muscle training group will utilize a linear pressoric resistance equipment with an inspiratory charge of 30% of maximum inspiratory pressure (adjusted weekly), during 7 days of the week, session duration of 30 minutes, during 8 weeks.

Primary Outcome Measures

Name	Time	Method
Calf blood flow	8 weeks

Secondary Outcome Measures

Name	Time	Method
Time to exercise tolerance (tlim)	8 weeks	Exercise time during high intensity submaximal Cardiopulmonary exercise testing
Maximum Inspiratory Pressure	8 weeks
The St George's Respiratory Questionnaire	8 weeks
Calf vascular resistance	8 weeks	Calf blood flow/mean arterial pressure
Baseline Dyspnea Index/Transitional Dyspnea Index	8 weeks

Trial Locations

Locations (1)

Hospital de Clinicas de Porto Alegre; 🇧🇷 Porto Alegre, Rio Grande do Sul, Brazil