Dynamic diaphragm function trajectory via ultrasound predicts weaning outcomes in mechanically ventilated patients

Plain English summary of protocol

Background and study aims
Mechanical ventilation (MV) is a lifesaving intervention for critically ill patients with respiratory failure. However, the process of liberating patients from the ventilator, known as weaning, remains a significant clinical challenge. Approximately 20-30% of patients experience weaning failure, which is associated with dramatically increased morbidity, mortality, and healthcare costs. Prolonged ventilation can lead to complications such as ventilator-associated pneumonia, diaphragm dysfunction, and ICU-acquired weakness.
Traditional weaning predictors (e.g., rapid shallow breathing index) and clinical parameters often lack sufficient sensitivity and specificity. Recent evidence highlights the critical role of the diaphragm. Ventilator-induced diaphragmatic dysfunction (VIDD) can develop within hours of controlled ventilation and is a key contributor to weaning failure. Bedpoint ultrasonography has emerged as a non-invasive, real-time tool to assess diaphragmatic structure and function through metrics like diaphragmatic thickness, thickening fraction (DTF), and mobility.
However, most studies provide only single or intermittent "snapshots" of diaphragmatic function. The dynamic trajectory of these ultrasound parameters over the course of mechanical ventilation—how they change from initiation, through support, to weaning trials—is poorly characterized but may hold superior prognostic value for weaning outcomes. A detailed understanding of this trajectory could enable earlier identification of patients at risk for diaphragm dysfunction and weaning failure, allowing for timely, personalized interventions such as adjusted ventilator settings, targeted physiotherapy, or pharmacological support.

The Diaphragm-Protective Ventilation (DMV) study is a single-center, prospective cohort study designed to address this knowledge gap. Its primary objective is to establish and validate the predictive value of the longitudinal trajectory of ultrasound-assessed diaphragmatic function for weaning outcomes in critically ill, mechanically ventilated patients. The findings are intended to provide evidence for the early identification of diaphragmatic dysfunction and the optimization of weaning strategies in clinical practice.

Who can participate?
Adult patients aged 18 years old and over receiving invasive mechanical ventilation in the Intensive Care Unit (ICU).

What does the study involve?
This is a prospective cohort study to dynamically assess diaphragmatic function using bedside ultrasound to predict weaning outcomes in mechanically ventilated patients. During the study, researchers will perform ultrasound examinations every other day to monitor indicators such as diaphragmatic thickness, diaphragmatic thickening fraction, and diaphragmatic mobility.

What are the possible benefits and risks of participating?
Potential Benefits:
Participants will be managed under a refined ventilation strategy informed by dynamic ultrasound assessment of diaphragmatic function to predict weaning prognosis. This approach may help reduce the risk of ventilator-associated injury and potentially increase their chances of successful and earlier liberation from the ventilator.
Participants will receive close respiratory physiological monitoring.
Participant's research data will contribute to improving future respiratory treatment strategies for critically ill patients.
Potential Risks and Discomforts:
As an observational study, the primary risk involves participation in more frequent ultrasound examinations. However, ultrasound is a routine, non-invasive, and radiation-free bedside procedure.

Where is the study run from?
This study is conducted in the Intensive Care Unit (ICU) of The First Affiliated Hospital of Jinan University, China.

When is the study starting and how long is it expected to run for?
March 2026 to January 2030.
Total Study Duration: The entire research project (including recruitment, follow-up, and data analysis) is expected to last approximately 4 years.

Who is funding the study?
The First Affiliated Hospital of Jinan University, China.

Who is the main contact?
Dr. Wan-Jie Gu, guwanjie@jnu.edu.cn.

Contact information

Prof Wan-Jie Gu
Public, Principal investigator, Scientific

613 Huangpu Avenue West
Guangzhou
510630
China

ORCID ID	0000-0003-4923-8282
Phone	+86 15850546835
Email	guwanjie@jnu.edu.cn

Study information

Eligibility

Locations

Countries of recruitment

• China

Study participating centres

Results and Publications

Editorial Notes

10/03/2026: Study’s existence confirmed by the Scientific Research Ethics Committee of the First Affiliated Hospital of Jinan University, China.