Diaphragmatic Ultrasound as a Guide Tool During Weaning From Mechanical Ventilation

Study Overview
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Brief Summary
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To assess value of adding ultrasound derived variables to the usual parameters on success rate of weaning from mechanical ventilation in critically ill patients and to validate sensitivity and specificity of ultrasound derived variables (thickening fraction /diaphragmatic excursion)

Detailed Description
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Difficult weaning from mechanical ventilation (MV) is a common problem in critically ill patients. Many parameters have been developed to aid weaning from MV such as P/F ratio (PO2/FiO2) and rapid shallow breathing index (respiratory rate/tidal volume), however, sensitivity and specificity for most variables are still variable in literature. Multiple studies have found that patients tolerantof SBTs were found to have successful discontinuationsat least 77% of the time. Causes of weaning failure include: airway and lung dysfunction, brain dysfunction, cardiac dysfunction, diaphragm dysfunction, and endocrine dysfunction . Diaphragmatic dysfunction is a common cause of weaning failure , however most of the traditional methods used for evaluation of diaphragmatic function (fluoroscopy, trans-diaphragmatic pressure measurement) are invasive and not available. Ultrasound assessment of diaphragmatic function has been developed recently providing an easy and safe method for evaluation of diaphragmatic excursion and thickening. It was found that weaning failure (Re-intubation within 48 hours) was associated with diaphragmatic excursion <1 cm and thickening fraction <28% several studies reported the value of diaphragmatic ultrasound to predict weaning failure ,however no one of them used diaphragmatic ultrasound to guide weaning. previous studies showed that failure rate of weaning from mechanical ventilation was 27% ,however failure rate in our department was 43% adding ultrasound derived values aims for improving success rate of weaning from mechanical ventilation.

Official Title
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Diaphragmatic Ultrasound as a Guide Tool During Weaning From Mechanical Ventilation (Randomized Controlled Trial)

Conditions
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Diaphragmatic Ultrasound in Weaning

Intervention / Treatment
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* Device: diaphragmatic ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Critically ill patients intubated for more than 48 hours who are ready for weaning Exclusion Criteria: • Age < 18 years surgical dressings over the right lower rib cage which would preclude ultrasound examination patients with chest trauma, thoracotomy, diaphragmatic paralysis, diaphragmatic injury and diaphragmatic surgery patients with neuromuscular diseases ( myasthenia gravis ,Muscular dystrophies ,Multiple sclerosis and Amyotrophic lateral sclerosis)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Group S<br>weaning readiness will be evaluated with the standard criteria :- A) Clinical assessment:- Resolution of acute phase of disease for which patient was intubated Adequate cough Absence of excessive tracheobronchial secretions B) Objective criteria:- Adequate oxygenation:PaO2>60mmHg with PEEP<8,SaO2>90%,FIO2 <0.5,PaO2/FIO2>200 Respiratory rate <30 PH and PaCO2 appropriate for patients' baseline respiratory status Hemodynamically stable :minimal or no vasopressor/inotropes,no evidence of myocardial ischemia HR<140 beats/minute Patient is arousable or Glasgow coma scale (GCS)>13 | |
| Experimental: Group SD<br>weaning readiness will be evaluated with the following criteria:- A) Clinical assessment:- Resolution of acute phase of disease for which patient was intubated Adequate cough Absence of excessive tracheobronchial secretions B) Objective criteria:- Adequate oxygenation:PaO2>60mmHg with PEEP<8,SaO2>90%,FIO2 <0.5,PaO2/FIO2>200 Respiratory rate <30 PH and PaCO2 appropriate for patients' baseline respiratory status Hemodynamically stable :minimal or no vasopressor/inotropes,no evidence of myocardial ischemia HR<140 beats/minute Patient is arousable or Glasgow coma scale (GCS)>13 C) Ultrasound criteria:- • Diaphragmatic excursion >11 mm | Device: diaphragmatic ultrasound<br>* Diaphragmatic excursion; Diaphragmatic movement will be measured with a 3.5-MHz US probe (Mindray machine, DC-N6).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Success rate of weaning from mechanical ventilation in both groups | (The trial will be considered a successful weaning trial if the patient passed 48 hours without the need for neither invasive nor non-invasive ventilation) | 48 Hours after weaning | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Rapid shallow breathing index (RSBI) and its correlation with ultrasound derived variables |  | baseline | 
| • Days of ventilation (before weaning trial) in correlation to diaphragmatic dysfunction |  | baseline | 
| • Number of weaning trials prior to inclusion in the study |  | baseline |