Evaluation of Diaphragmatic Function in Mechanically Ventilated Patients With Transient Shear Wave Elastography
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 30
- Locations
- 2
- Primary Endpoint
- Change in transdiaphragmatic pressure
Study Overview
Brief Summary
Mechanical ventilation is a life-saving treatment that can be associated with diaphragm dysfunction, a potentially deleterious acquired disability. It may be the consequence of disuse - under mechanical ventilation, respiratory muscles are unloaded - or the consequence of muscle overuse because of insufficient unloading. Evaluating diaphragm function is therefore crucial to optimally tailor the ventilator assistance. Measurement of transdiaphragmatic pressure (Pdi) is the reference method to assess diaphragm function but it invasiveness hinders the generalization of its use. Previous studies have reported that ultrasound can quantify diaphragm thickening and that diaphragm thickening fraction (TFdi) is a good marker of diaphragm function. Since diaphragm becomes stiffer when it contracts, the investigators aim at exploring whether the measurement of diaphragm stiffness by transient shear wave elastography would improve the evaluation of diaphragm function with ultrasound.
Therefore, the objectives of the study are to evaluate the performance of transient shear wave elastography applied to the diaphragm to estimate Pdi in mechanically ventilated patients as compared to TFdi and to correlate the changes in elastography derived indices, in TFdi and in Pdi into different ventilatory conditions and during a spontaneous breathing trial. Pdi will be obtained using catheters positioned in patients' stomachs and esophagus and diaphragm stiffness will be assessed by measuring the shear modulus of the diaphragm with a dedicated ultrasound machine (Aixplorer, Ultrasonic). TFdi will be also measured as previously reported. Pdi, TFdi and shear modulus will be measured at the end of each four following 10 minutes-conditions: 1) baseline with initial ventilator settings (set by the physician in charge of patient); 2) 25%-increase in pressure support and initial PEEP; 3) 25%-decrease in pressure support and initial PEEP and 4) initial level of pressure support and ZEEP. Finally, the same measurements will be done at the beginning of a 30 minutes spontaneous breathing trial.
Detailed Description
Objective :
The main objective is to correlate ultrasound indices (thickness, thickening, rigidity) to the measurement of transdiaphragmatic pressure in the evaluation of the diaphragmatic function of patients under mechanical ventilation.
Secondary objectives are: 1. Correlate thickening of the diaphragm with Pdi, 2. Correlate diaphragmatic thickening with diaphragmatic stiffness 3. Describe these correlations under different levels of pressure ventilatory support, 4. Describe the evolution of diaphragmatic stiffness, thickening and Pdi pressure during a ventilator liberating trial.
The primary endpoint is the measurement of Pdi. The secondary endpoints are the diaphragm thickening fraction and diaphragm stiffness.
Methods :
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Diagnostic
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Outcomes
Primary Outcomes
Change in transdiaphragmatic pressure
Time Frame: Through patient participation, an average of 1 day
Reference method to assess diaphragm function computed as the difference between esophageal pressure and gastric pressure
Secondary Outcomes
- Success or failure at the spontaneous breathing trial(Through patient participation, an average of 1 day)
- Change in diaphragm stiffness(Through patient participation, an average of 1 day)
- Change in diaphragm thickness and thickening as expressed by the thickening fraction (ratio of the difference between inspiratory and expiratory thickness over expiratory thickness).(Through patient participation, an average of 1 day)