dTDI During a SBT to Predict Extubation Failure in Preterm Infants

Study Overview
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Brief Summary
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Weaning from mechanical ventilation is a critical issue and the diaphragmatic disfunction has been demonstrated to play an important role in extubation failure. the aim of present investigation is to evaluate diaphragmatic excursion velocity during in patients undergoing spontaneous breathing trial through tissue Doppler analysis in both inspiration and expiration.

Official Title
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Diaphragmatic Tissue Doppler Imaging During a Spontaneous Breathing Trial to Predict Extubation Failure in Preterm Infants

Conditions
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Premature

Intervention / Treatment
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* Device: diaphragmatic tissue Doppler imaging，dTDI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: premature infants with gestational age <32 weeks and supported by invasive mechanical ventilation ≥48 hours All the indications for extubation are met：cough or vomiting due to spontaneous breathing and sputum aspiration; ventilator parameters in recent 24 hours: MAP < 8cmH2O, RR < 30 times/min, FiO2 < 30%; Arterial blood gas: pH > 7.25, (PaCO2< 60mmHg, BE < 8mmol/L, oxygen saturation > 90% a successful SBT parents or legal guardians sign informed consent to attend this study Exclusion Criteria: accidental extubation chest CT or bronchoscopy during hospitalization indicated congenital airway dysplasia complex congenital heart disease congenital metabolic diseases, neuromuscular diseases severe brain injury surgical mechanical ventilation give up before extubation; pneumothorax or pleural effusion no consent is signed

Ages Eligible for Study
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Minimum Age: 2 Days
Maximum Age: 6 Months

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| the failure group<br>Re-intubation within 48 h after passing the SBT was defined as failed weaning. | Device: diaphragmatic tissue Doppler imaging，dTDI<br>* dTDI was performed at the end of the SBT to assess excursion, velocity, and acceleration.<br>|
| the success group<br>Extubation and invasive mechanical ventilation was not needed within 48 h after extubation was defined as successful weaning. | Device: diaphragmatic tissue Doppler imaging，dTDI<br>* dTDI was performed at the end of the SBT to assess excursion, velocity, and acceleration.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in diaphragmatic displacement velocity | Inspiratory and expiratory diaphragmatic displacement velocity evaluated with tissue doppler during the assisted ventilation modality which preceded the trial, during the spontaneous breathing trial and in spontaneous breathing. | an average of 20 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diaphragmatic acceleration and deceleration | Diaphragmatic acceleration and deceleration evaluated with tissue doppler during the assisted ventilation modality which preceded the trial, during the spontaneous breathing trial and in spontaneous breathing. | an average of 20 minutes | 
| Gas exchange - arterial carbon dioxide tension | Arterial blood gases sample | through each trial completion, an average of 20 minutes | 
| Gas exchange - pH | Arterial blood gases sample | an average of 20 minutes | 
| Gas exchange - arterial oxygen tension | Arterial blood gases sample | an average of 20 min | 
| Silverman Andersen Respiratory Severity Score (SA-RSS) | SA-RSS to assess work of breathing after extubation. | an average of 20 min | 
| Number of patients who experienced weaning failure | the need for non invasive ventilation or re-intubation due to any cause | 48 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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tissue Doppler imaging, Premature infants, extubation, diaphragm