Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT00000571 |
Other study ID # |
209 |
Secondary ID |
R01HL034019 |
Status |
Completed |
Phase |
Phase 3
|
First received |
October 27, 1999 |
Last updated |
December 28, 2015 |
Start date |
February 1986 |
Study information
Verified date |
April 2001 |
Source |
McGill University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
United States: Federal Government |
Study type |
Interventional
|
Clinical Trial Summary
To test the effectiveness of ventilatory muscle rest (VMR) using home negative pressure
ventilation (NPV) in improving exercise performance, alleviating dyspnea, and improving the
quality of life in patients with severe chronic obstructive lung disease.
Description:
BACKGROUND:
The potential importance of respiratory, chiefly inspiratory-muscle, fatigue had only
recently been appreciated. If inspiratory muscles fail, so does ventilation and tissue
respiration. There are theoretical reasons to postulate inspiratory muscle failure in
chronic obstructive pulmonary disease, and suggestions that it may occur in an acute form
with exacerbations and in a chronic form during 'stability'. There are two therapeutic
strategies available for prevention and treatment of inspiratory muscle fatigue: training
inspiratory muscles to increase their efficiency and resting fatigued muscles. The former
should work if chronic fatigue is not present, and the latter should allow recovery from
chronic fatigue, so the two approaches are not necessarily mutually exclusive. This proposal
was originally designed to test the efficacy of each of these therapies alone and also in
combination; however, given the experience of a pretrial period, these goals were scaled
back. Since there was reason to believe that VMR may be more effective than IMT, the trial
focused on VMR and sham VMR only.
Ventilatory muscle rest was applied using a negative pressure ventilation suit sealed at the
patient's hips, arms, and neck. A widebore tube connected to a fitting in the suit above the
grid on the chest and upper abdomen transmitted negative pressure to the chest wall from the
pump, thereby inflating the lungs.
The evidence for chronic inspiratory muscle fatigue in patients with COLD resided largely in
several relatively poorly controlled studies indicating that nocturnal artificial
ventilation, which presumably rested the inspiratory muscles, produced improvement in
daytime function and blood gases. The trial produced some badly needed data on both the
occurrence of inspiratory muscle fatigue in COLD patients and its treatment with VMR.
DESIGN NARRATIVE:
Randomized, blinded. A total of 1,231 patients in the metropolitan Montreal area were
screened. Of these, 348 were recruited to enter a four week stabilization period, and 184
were subsequently randomized to either active or sham negative pressure ventilation (NPV). A
five day in-hospital period was used to train patients in ventilator use and obtain baseline
measures of exercise capacity, lung function, respiratory symptoms, and quality of life.
Randomization was stratified on the basis of whether or not the patient had been receiving
oxygen at home. Home ventilation treatment took place during a following 12-week period.
Respirator use was recorded from patient logs and from concealed meters installed in the
units. Patients received four home visits by physiotherapists during the 12-week period and
returned to the hospital for follow-up at four and twelve weeks post-discharge for
reassessment. The principal outcome measure was the distance in meters walked in six
minutes. Secondary outcome measures were cycle exercise endurance time, severity of dyspnea,
quality of life, arterial blood gas tensions, and respiratory muscle strength.