Serial Diaphragm Ultrasound Evaluation During Inspiratory Muscle Training in Prolonged Mechanical Ventilation

NCT07709793 | Completed

• 1 other identifier: 202102400A3
• Study Type: interventional
• Target: 36
• Locations: 1 country
• Sites: 1

Brief Summary

Diaphragm dysfunction contributes to prolonged mechanical ventilation (PMV) and difficult weaning. Inspiratory muscle training (IMT) may improve respiratory muscle performance, while serial diaphragm ultrasound offers a bedside method for monitoring diaphragmatic recovery. This study used diaphragm ultrasound to evaluate the effects of high- versus low-intensity IMT in patients with PMV and diaphragm dysfunction. In this prospective study, patients received high- or low-intensity IMT for up to 2 weeks or until ventilator liberation. Respiratory mechanics, including respiratory rate, tidal volume, minute ventilation, rapid shallow breathing index, and maximal inspiratory pressure, were assessed twice weekly. Diaphragm excursion and thickening fraction were also measured serially after IMT initiation. Changes in respiratory physiological parameters and diaphragm ultrasound measurements were compared between the two IMT groups, and differences in ventilator liberation outcomes were evaluated.

Conditions

Prolonged Mechanical Ventilation

Keywords

diaphragm ultrasound; prolonged mechanical ventilation; ventilator weaning; inspiratory muscle training; training intensity, maximal inspiratory pressure

Outcome Measures

Primary Outcomes (2)

• Changes in diaphragm excursion measured by diaphragm ultrasound

  From enrollment to the end of study at 2 weeks.

• Changes in thickening fraction measured by diaphragm ultrasound

  From enrollment to the end of study at 2 weeks.

Secondary Outcomes (6)

• Successful ventilator liberation

  From enrollment to the end of study at 2 weeks.

• Change in maximal inspiratory pressure (PImax)

  From enrollment to the end of study at 2 weeks.

• Change in respiratory rate (RR)

  From enrollment to the end of study at 2 weeks.

• Change in tidal volume (VT)

  From enrollment to the end of study at 2 weeks.

• Change in minute ventilation (MV)

  From enrollment to the end of study at 2 weeks.

Study Arms (2)

high intensity IMT

EXPERIMENTAL

high IMT training intensity

Procedure: High intensity IMT

low intensity IMT

ACTIVE COMPARATOR

low IMT training intensity

Procedure: Low intensity IMT

Interventions

High intensity IMT PROCEDURE

high intensity IMT: high intensity training

high intensity IMT

Low intensity IMT PROCEDURE

low intensity IMT: low intensity training

low intensity IMT

Eligibility Criteria

• Age: 20 Years - 100 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Willing and able to provide written informed consent.
• Adults aged \>20 years.
• Patients requiring mechanical ventilation for \>21 days and admitted to the Respiratory Care Center (RCC).
• Hemodynamically stable and not receiving vasopressor therapy.
• Clinically stable and considered by the attending physician to be ready to begin weaning from mechanical ventilation. Ventilator settings must meet all of the following criteria:
• (1) Fraction of inspired oxygen (FiO₂) \< 0.60. (2) Positive end-expiratory pressure (PEEP) ≤10 cmH₂O. (3) Able to trigger spontaneous breaths on the ventilator. (4) Respiratory rate \<25 breaths/min. (5) Respiratory muscle weakness confirmed by maximal inspiratory pressure (MIP), defined as MIP \<30 cmH₂O.

You may not qualify if:

• Hemodynamic instability, including cardiac arrhythmia, decompensated heart failure, or acute coronary syndrome.
• Active hemoptysis.
• Presence of a chest tube.
• Use of home mechanical ventilation.
• Uncontrolled pain or dyspnea.
• Patients determined to be ventilator-dependent and requiring long-term mechanical ventilation.
• Patients or their legally authorized representatives who are unwilling or unable to provide written informed consent.

Sponsors & Collaborators

• Chang Gung Memorial Hospital: lead

Study Sites (1)

Linkou Gung Memorial Hospital

Taoyuan, Taiwan

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Attending Physician of Pulmonary and Critical Care Medicine

Study Record Dates

• First Submitted: July 7, 2026
• First Posted: July 17, 2026
• Study Start: March 9, 2023
• Primary Completion: May 27, 2025
• Study Completion: June 30, 2025
• Last Updated: July 17, 2026

Record last verified: 2026-07

Locations

TW (1)