Ventilator-based Inspiratory Muscle Training for Patients With Respiratory Failure

Ventilator-based Inspiratory Muscle Training: Trigger Sensitivity Adjustment Versus Stepwise Pressure Support Reduction for Patients With Respiratory Failure

This study will be conducted to compare the effectiveness of progressive inspiratory flow trigger sensitivity rising versus stepwise pressure support reduction as ventilator-based inspiratory muscle training methods on weaning and extubation success in mechanically ventilated patients with respiratory failure.

Study Overview

• Status: Not yet recruiting
• Conditions: Respiratory Failure; Mechanical Ventilation Complication
• Intervention / Treatment: Other: routine plan of weaning and Conventional Chest Physiotherapy; Other: adjustment of parameters on mechanical ventilation device

Detailed Description

Acute respiratory failure (ARF) remains a leading contributor to morbidity and mortality in intensive care settings. It accounts for approximately 10% to 15% of medical ICU admissions and up to 50% to 75% of prolonged ICU stays exceeding seven days, with a reported mortality rate of around 40%. Inspiratory muscle weakness is common in mechanically ventilated patients, particularly with prolonged ventilation. Inspiratory muscle training could limit or reverse these detrimental effects and promote quicker, successful weaning. Unfortunately, especially when the weaning process started late, the significant loss of muscle strength means that between 5% and 15% of patients being weaned repeatedly fail to regain respiratory autonomy. Several strategies aim to reduce weaning duration and MV time in patients requiring prolonged ventilation, including inspiratory muscle training (IMT); however, evidence for its effectiveness remains limited and inconsistent. Alternatively, ventilator-based approaches such as trigger sensitivity optimization or gradual pressure support (PS) reduction offer valid equipment-free methods that may preserve muscle activity and enhance synchrony. Despite their potential, these strategies have not been rigorously evaluated in randomized controlled trials.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Mahmoud E Ragab, MSc; Phone Number: +201001218587; Email: mr.syndrome.264@gmail.com
• Study Contact Backup: Name: SHYMAA T Mohamed, PhD; Phone Number: +201021088610; Email: Shimaa.taha395@gmail.com

Study Locations

• Egypt
  • Giza Governorate
    • Cairo, Giza Governorate, Egypt, 11956
      • kasr Al Ainy Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Acute respiratory failure patients in the ICU are receiving MV for 48 h or more in a controlled mode.
• Their ages will range from 40 to 55 years old, and both sexes will be included.
• Conscious and oriented patients with a Glasgow coma score ≥13 (≥9T).
• Alertness score with a Richmond Agitation-Sedation Scale (RASS) will be from 0 to -1.
• All patients in this study must be hemodynamically and medically stable.
• Patients must be able to trigger spontaneous breaths on the ventilator but couldn't generate maximum inspiratory pressure more than -15 mbar.

Exclusion Criteria:

• Persistent hemodynamic instability as life-threatening conditions or comorbidities interfere with and compromise weaning, like cardiac arrhythmia, pericardial effusion, congestive heart failure, or acute coronary syndrome.
• Severe breathlessness when spontaneously breathing.
• Any progressive neuromuscular disease, such as myopathy or neuropathy, that would interfere with responding to inspiratory muscle training due to inadequate training performance of the inspiratory muscle.
• Spinal cord injury.
• Skeletal pathology (scoliosis, flail chest, spinal instrumentation) that would seriously impair the movement of the chest wall and ribs.
• Patients in a coma or under heavy sedation (RASS ≤ -2) and with respiratory muscle paralysis.
• High peak airway pressure (barotrauma), high PEEP >10, or active pneumothorax.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Conventional Chest Physiotherapy; twenty mechanically ventilated patients with acute respiratory failure, who will receive the routine plan of weaning and conventional chest physiotherapy from MV twice a day with a 4-6 hour gap between for 4-5 days a week till extubation.	Other: routine plan of weaning and Conventional Chest Physiotherapy; Chest Physiotherapy including: ▪ Postural Drainage ▪ Manual techniques for airway clearance (percussion, vibration, shaking) Adding to range of passive to active movements of the limbs
Experimental: Trigger Sensitivity IMT; twenty mechanically ventilated patients with acute respiratory failure, who will receive inspiratory muscle training by gradual inspiratory flow trigger sensitivity optimization in addition to the routine plan of weaning and conventional chest physiotherapy from MV, twice a day with a 4-6 hour gap between, for 4-5 days a week till extubation.	Other: routine plan of weaning and Conventional Chest Physiotherapy; Chest Physiotherapy including: ▪ Postural Drainage ▪ Manual techniques for airway clearance (percussion, vibration, shaking) Adding to range of passive to active movements of the limbs; Other: adjustment of parameters on mechanical ventilation device; adjust the parameters of the mode of training on mechanical ventilation according the group of patients
Experimental: Stepwise Pressure Support Reduction IMT; twenty mechanically ventilated patients with acute respiratory failure, who will receive inspiratory muscle training via stepwise pressure support reduction in addition to the routine plan of weaning and conventional chest physiotherapy from MV, twice a day with a 4-6 hour gap between, for 4-5 days a week till extubation.	Other: routine plan of weaning and Conventional Chest Physiotherapy; Chest Physiotherapy including: ▪ Postural Drainage ▪ Manual techniques for airway clearance (percussion, vibration, shaking) Adding to range of passive to active movements of the limbs; Other: adjustment of parameters on mechanical ventilation device; adjust the parameters of the mode of training on mechanical ventilation according the group of patients

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Spontaneous breathing trial (SBT)	documenting the frequency (total number) of spontaneous breathing trials for each patient until successful extubation	From initiation of the first SBT until successful extubation, up to 48 hours
Burn's Wean Assessment Score	Calculate the percentage of the total score to indicate the extent of improvement and the probable readiness for weaning (in %). The 26-item checklist assigns 1 point for "yes" responses, with a total score up to 26. Scores below 17 (65%) suggest insufficient readiness for weaning, while scores ≥ 17 indicate probable readiness for weaning.	baseline (Day 1, prior to intervention) and immediately before initiation of successful SBT
Duration of MV	defined as the time from study randomization to successful unassisted breathing (in days)	from randomization to successful unassisted breathing, up to 48 hours
weaning success rate	absence of ventilatory support 48 hours after discontinuation of MV. Inability to tolerate or pass SBT or to be liberated from invasive ventilatory support indicates weaning failure (in %).	Within 48 hours following extubation
Extubation success rate	defined as the proportion of subjects who did not die and were not re-intubated 48-72 hours after the scheduled extubation. The inability to sustain spontaneous breathing after removal of the endotracheal tube, requiring either reintubation or the use of NIV within this specified period, indicates extubation failure (in %).	Within 72 hours following extubation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Gas analysis	Measure the results of the arterial blood gas analysis before beginning the intervention and follow up on its progression through the study and get the final results once weaning occurs. Lower PaCO₂ during MV is independently associated with successful weaning, while higher levels are linked to weaning failure	baseline (Day 1, prior to intervention) and within 48 hours after liberation from mechanical ventilation
Negative Inspiratory Force	Negative inspiratory force (cmH₂O) will be measured via the mechanical ventilator as an index of global inspiratory muscle strength, consistent with ATS/ERS recommendations for weaning assessment.	Baseline (Day 1, prior to intervention) and immediately following completion of successful SBT
Respiratory Rate	Respiratory rate (breaths/min) will be measured from the mechanical ventilator as an indicator of respiratory load and breathing pattern	Baseline (Day 1, prior to intervention) and immediately following completion of successful SBT
Minute Ventilation	Minute ventilation (L/min) will be measured from the mechanical ventilator.	Baseline (Day 1, prior to intervention) and immediately following completion of successful SBT
Static Lung-Thorax Compliance	Static lung-thorax compliance (mL/cmH₂O) calculated from ventilator parameters.	Baseline (Day 1, prior to intervention) and immediately following completion of successful SBT
Rapid Shallow Breathing Index	The Rapid Shallow Breathing Index (breaths/min/L) is calculated as respiratory rate divided by tidal volume (RSBI).	Baseline (Day 1, prior to intervention) and immediately following completion of successful SBT
The Horowitz index (also known as the oxygenation or Carrico index)	The PaO₂/FiO₂ ratio is a key indicator of hypoxemia severity and pulmonary recruitment in respiratory failure. Normal values range from 400 to 500 mmHg, while values below 300 mmHg indicate pulmonary dysfunction	baseline (Day 1, prior to intervention) and within 48 hours after liberation from mechanical ventilation
Integrative weaning index	It is a composite parameter that was calculated as the product of static compliance (Cst), arterial oxygen saturation, and the RR/TV "RSBI": IWI = Cst × SaO2/RSBI (mL/cm H2O breath/minute/L). It is a reliable and accurate tool for predicting SBT outcomes and determining readiness for spontaneous breathing as an initial weaning step. An oxygen concentration of 0.35 will be preset prior to calculation, as it influences the outcome based on the formula. A value above 25 indicates a likelihood of successful weaning.	baseline (Day 1, prior to intervention) and immediately before initiation of successful SBT

Collaborators and Investigators

• Sponsor: Cairo University
• Investigators: Principal Investigator: Mahmoud E Ragab, M.Sc., Kasr Al Ainy hospital, Cairo University; Study Chair: Nesreen G' EL-NAHAS, PhD, Cairo University

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): March 1, 2027

Study Registration Dates

• First Submitted: December 1, 2025
• First Submitted That Met QC Criteria: January 17, 2026
• First Posted (Actual): January 20, 2026

Study Record Updates

• Last Update Posted (Actual): January 20, 2026
• Last Update Submitted That Met QC Criteria: January 17, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Respiratory Insufficiency
• Other Study ID Numbers: VENTILATOR-BASED TRAINING

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: data is available with the corresponding author on reasonable request

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No