Inspiratory Muscle Training for Mechanical Ventilator Weaning

(FLEX Trial)

Overseen By Annia Schreiber, MD

Age: Any Age

Sex: Any

Trial Phase: Academic

Sponsor: Unity Health Toronto

Disqualifiers: Severe neuromuscular disorders, chronic respiratory failure, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 5

10 Participants Needed

Trial Summary

What is the purpose of this trial?

Respiratory muscle dysfunction is highly prevalent in patients with prolonged weaning from mechanical ventilation and is strongly associated with weaning failure. Efforts to strengthen the respiratory muscles, aimed at reversing or minimizing the impact of respiratory muscle weakness on clinical outcomes, have generally focused on the diaphragm with specific inspiratory muscle training (IMT) exercises. However, the effectiveness of these exercises and impact on clinical outcomes are not current practice in the majority of ICUs, as they are hardly feasible in ICU patients who often cannot be disconnected from the ventilator and cannot fully cooperate. Promising results have been published concerning non-respiratory training techniques, which can also target the accessory muscles, particularly important in the presence of increased load to the respiratory system, as in the case of the weaning phase. These non-respiratory training techniques would have the advantage of not entailing disconnection of the patient from the ventilator. In particular, in healthy subjects, a quasi-isometric neck contraction, called neck flexion, appeared to generate greater or comparable recruitment of some principal and accessory muscles of respiration, when compared to conventional IMT. However, this has not been studied in patients requiring prolonged mechanical ventilation, for whom IMT with threshold loading devices remains the primary recommended rehabilitation strategy. Therefore, the primary aim of the investigators is to assess the feasibility, tolerability, and safety of neck flexion and to compare them with IMT technique in patients with difficult and prolonged weaning from mechanical ventilation. Secondary aims are: i) to characterize which respiratory muscles are recruited and their level of activation at different levels of ventilatory assistance and ii) to assess which respiratory muscles are recruited and their level of activation during the two techniques and to compare these findings. The hypothesis of the investigators is that neck flexion will be feasible (more than conventional IMT), well tolerated, and safe in patients with difficult and prolonged weaning. The investigators also hypothesize that, reducing the level of assistance and during unassisted breathing, a progressively increasing activation of the diaphragm, neck and trunk respiratory muscles, reflecting increased ventilatory load, will be fund. Finally, the hypothesis of the investigators is that the level of muscle activation/recruitment during neck flexion will be comparable or even greater to that occurring during IMT, as found in healthy subjects. Finding a new and highly feasible rehabilitative technique, able to recruit and train the respiratory muscles (including accessory muscles), will have the potential to promote patients' weaning and improve all related clinical outcomes, and therefore to dramatically shift the paradigm about the role of rehabilitation in ICU.

Eligibility Criteria

This trial is for patients over 16 years old who are on mechanical ventilation due to difficulty weaning off it. They must have failed extubation or breathing trials, be able to trigger the ventilator spontaneously, and be in stable condition with adequate oxygen levels. Participants need to understand simple instructions.

Inclusion Criteria

I use a ventilator due to difficulties in breathing on my own and have had unsuccessful attempts at breathing without it.

I am 16 years old or older.

I can breathe with minimal ventilator support.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

1 week

Baseline Measurements

Baseline measurements including ultrasound and sEMG of respiratory muscles are performed

Up to 72 hours from admission

1 visit (in-person)

Training Phase

Participants undergo Inspiratory Muscle Training (IMT) and Quasi-Isometric Neck Flexion once a week

4 weeks

4 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after training

4 weeks

Treatment Details

Interventions

• Inspiratory Muscle Training
• Quasi-Isometric Neck Flexion

Trial Overview The study tests neck flexion exercises against inspiratory muscle training (IMT) in mechanically ventilated patients struggling with weaning. It aims to see if neck flexion can recruit respiratory muscles effectively without disconnecting from the ventilator.

Participant Groups

Group I: Quasi-Isometric Neck Flexion Experimental Treatment 2 Interventions

On minimal mechanical ventilation support (unassisted/assisted spontaneous breathing) via tracheostomy. Quasi-Isometric Neck Flexion will be performed during mechanical ventilation. Patients will be asked to minimally lift their head from the pillow generating a quasi-isometric neck contraction. 30% will be the target intensity level for neck flexion. The patient will perform 2 sets of 6-10 quasi-isometric neck flexions.

Group II: Inspiratory Muscle Training Experimental Treatment 2 Interventions

Perform 2 sets of 6-10 breaths through a POWERbreathe device, which applies a variable resistance provided by an electronically controlled valve (variable flow resistive load). The training device will be set at 30% of the highest value of three MIP maneuvers. A two-minute rest period with MV support will be provided between each set.

Inspiratory Muscle Training is already approved in European Union, United States, Canada for the following indications:

Approved in European Union as Inspiratory Muscle Training for:

• Chronic Obstructive Pulmonary Disease (COPD)
• Congestive Heart Failure
• Spinal Cord Injury
• Multiple Sclerosis

Approved in United States as Inspiratory Muscle Training for:

• Chronic Obstructive Pulmonary Disease (COPD)
• Congestive Heart Failure
• Spinal Cord Injury
• Multiple Sclerosis
• Cardiac Rehabilitation

Approved in Canada as Inspiratory Muscle Training for:

• Chronic Obstructive Pulmonary Disease (COPD)
• Congestive Heart Failure
• Spinal Cord Injury
• Multiple Sclerosis

Who Is Running the Clinical Trial?

Unity Health Toronto

Lead Sponsor

Trials

572

Recruited

470,000+