Transcutaneous Carbon Dioxide Pressure (tcPCO2) Monitoring for the Prediction of Extubation Failure in the ICU

Study Overview
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Brief Summary
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Difficult weaning from ventilation and extubation failure are major issues in intensive care, concerning 30% and 12% of patients respectively. These can be partly explained by the lack of accuracy of spontaneous breathing trial (SBT) failure criteria to predict extubation failure. The investigators performed a pilot study to evaluate transcutaneous carbon dioxide pressure (tcPCO2) monitoring during SBTs. The results showed that the difference between maximum and initial tcPCO2 (or ΔtcPCO2) was significantly higher in the group of patients who failed SBTs according to the usual criteria. Moreover, the results suggested that ΔtcPCO2 could be an accurate and early criterion for SBT failure. The size of the study could not examine ΔtcPCO2 regarding extubation failure. Therefore, the main objective of this study is to determine if Δ tcPCO2 during SBTs is associated with extubation failure.

Official Title
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Is Transcutaneous Carbon Dioxide Pressure (tcPCO2) Monitoring During Spontaneous Breathing Trials Useful to Predict Extubation Failure in Mechanically Ventilated Patients in the ICU?

Conditions
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Ventilator Weaning

Intervention / Treatment
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* Procedure: tcPCO2 measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: > 18 years old, ICU indicated invasive mechanical ventilation via orotracheal or nasotracheal intubation presence of criteria for initiation of the weaning process as stated on our ICU's protocol resolution of the disease leading to mechanical ventilation Exclusion Criteria: mechanical ventilation during less than 24 hours Tracheotomy and tracheostomy at ICU admission Pregnancy Patient under legal protection Patient enrolled in another study regarding weaning or CO2 metabolism

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
Intervention Model: Single Group Assignment
Interventional Model Description: tcPCO2 will be monitored in all patients performing SBTs. The difference between maximal and initial tcPCO2 (ΔtcPCO2) in patients succeeding extubation will be compared with ΔtcPCO2 in patients failing extubation.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: tcPCO2 measurement arm<br>Patients will be monitored by tcPCO2 during spontaneous breathing trials | Procedure: tcPCO2 measurement<br>* tcPCO2 continuous monitoring during spontaneous breathing trials<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference between maximum and initial tcPCO2 (ΔtcPCO2) during SBTs in patients who fail extubation compared to patients who have been successfully extubated. | Extubation failure: need for reintubation, rescue non invasive ventilation or death within 7 days following extubation | 7 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between ΔtcPCO2 and extubation failure after adjustment on post extubation ventilation protocols (preventive non invasive ventilation or preventive Optiflow) | Different post-extubation ventilation protocols may include preventive non invasive ventilation or Optiflow. | 7 days | 
| Association between extubation decisions and ΔtcPCO2. |  | 1 week | 
| Adverse Events associated with tcPCO2 monitoring. |  | 1 week | 
| Optimal ΔtcPCO2 threshold to predict extubation failure by a ROC curve. |  | 7 days | 
| Compare ROC curves obtained by different extubation failure predictors | ROC curves obtained with: usual SBT failure criteria deltatcPCO2 alone usual criteria and ΔtcPCO2 combined shallow breathing index shallow breathing index and ΔtcPCO2 combined ΔtcPCO2, shallow breathing index and usual SBT failure criteria combined | 7 days | 
| Determine if ΔtcPCO2 is an early predictor of extubation failure (happening before other criteria of failed SBT) |  | 7 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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