Assessments of Diaphragm-pleural Mechanics During the Weaning From Prolonged Mechanical Ventilation

Weaning failure from mechanical ventilator is commonly seen in respiratory failure and increases duration of ventilator use, ICU stay, ventilator associated pneumonia and even mortality. The diaphragm serves as one of the most important respiratory mechanism and its function differs the weaning success rate. Since 1980s, ultrasonography assessment in diaphragm movement were developed and further discussion upon whether it serves as a predicting factor for extubation failure. The measurement includes difference of diaphragm thickness, diaphragm excursion or the movement of liver and spleen.

Multiple studies targeted intubated patients with different measurement methods and all resulted with good weaning prediction value.6 Of all the studies, only one study targeted tracheostomy tube patients. They reported diaphragm thickness fraction >36% as cutoff value is associated with successful spontaneous breathing trial (SBT), with a sensitivity of 0.82, specificity of 0.88. However, little comparison with traditional weaning parameters was mentioned in the study. We designed this prospective observational study to evaluate whether diaphragm movement under ultrasound serves as a predicting index of ventilator discontinuation in patients with tracheostomy. The diaphragm movement will also correlate with other parameters such as RSBI, Pi max, Pe max, Tv spont., WEANSNOW score(WS), VO2, APACHE II. Esophageal pressure is also provided as an option for our study population for more information such as pleural pressure, transdiaphragm pressure, etc.

The ultrasonography measurement of diaphragm movement will be performed within 6 hours before discontinuation of ventilator. The patient remains in semi-recumbent position with the convex probe selected for its good penetration. The probe is placed at a craniocaudal axis, 90 degrees to the skin at the lower intercostal spaces to right anterior axillary line (AAL) and left posterior axillary line (PAL), which allows a perpendicular ultrasound beam direction to the diaphragm movement. Liver (border or vascular structure), splenic (border or vascular structure) will be selected as target point and the marked distance of movement during quiet respiration cycle will be measured 10 times with a largest value calculated. Other echo measurements will also be attempted.

The study aims to investigate if the measurement of the diaphragm movement serves as a reliable predicting factor for weaning failure in respiratory care center patients.

Study Overview

• Status: Unknown
• Conditions: Respiratory Failure; Ventilator Weaning
• Intervention / Treatment: Device: Diaphragm ultrasound assessment & Esophageal pressure measurement

• Study Type: Observational
• Enrollment (Anticipated): 200

Contacts and Locations

Study Locations

• Taiwan
  • Taipei, Taiwan
    • Recruiting
    • National Taiwan University Hospital
    • Contact: Chang-Wei Wu, MD; Phone Number: +886952532943; Email: sinceadidas@hotmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: N/A
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients with prolonged mechanical ventilation with tracheostomy tube with admission to respiratory care center in NTUH

Description

Inclusion Criteria:

• Prolonged mechanical ventilation with tracheostomy tube
• Oxygen with a fraction of ≤ 0.4
• Positive end expiratory pressure at ≤ 5 cm H2O
• Pressure support at ≤ 8 cmH2O

Exclusion Criteria:

• No spontaneous breathing
• Unstable hemodynamic status,
• History of peritonitis, intraabdominal operation, empyema, or pleurodesis.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Prolonged mechanical ventilation; Prolonged mechanical ventilation with tracheostomy	Device: Diaphragm ultrasound assessment & Esophageal pressure measurement; Diaphragm ultrasound assessment and/or Esophageal pressure measurement before, during and after spontaneous breathing trial

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weaning success	Liberation from mechanical ventilation	1 month

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ventilator free 30 days after liberation	No mechanical ventilation use in 30 days after liberation	30 days after liberation
Ventilator free 60 days after liberation	No mechanical ventilation use in 30 days after liberation	60 days after liberation
Ventilator free 90 days after liberation	No mechanical ventilation use in 90 days after liberation	90 days after liberation

Collaborators and Investigators

• Sponsor: National Taiwan University Hospital

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2019
• Primary Completion (Anticipated): June 30, 2021
• Study Completion (Anticipated): December 31, 2021

Study Registration Dates

• First Submitted: February 12, 2019
• First Submitted That Met QC Criteria: February 12, 2019
• First Posted (Actual): February 15, 2019

Study Record Updates

• Last Update Posted (Actual): March 25, 2020
• Last Update Submitted That Met QC Criteria: March 24, 2020
• Last Verified: March 1, 2020

More Information

Terms related to this study

• Keywords: Pleural pressure; Esophageal pressure; Prolonged mechanical ventilation
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Respiratory Insufficiency
• Other Study ID Numbers: 201811015RINA

Drug and device information, study documents

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