Ultrasound Assessment of Changes in the Diameter of the Common Carotid Artery After Increasing the Preload of the Heart

Study Overview
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Brief Summary
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Passive leg raise (PLR) and fluid challenge are useful tools in assessing the fluid responsiveness. However, they require continuous monitoring of cardiac output, which is usually an invasive technique and in some cases not always available. Vascular ultrasound can be an alternative to cardiac output monitoring in a fluid status evaluation. The common carotid artery (CCA) is an easily accessible vessel. It has recently been noted that the diameter of this artery changes after an intravenous fluid bolus. It is possible that the change in the diameter of the common carotid artery during passive leg raise and fluid challenge can be a predictor of fluid responsiveness.

Official Title
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Ultrasound Assessment of Changes in the Diameter of the Common Carotid Artery After Increasing the Preload of the Heart With Passive Leg Raise and Intravenous Fluid Infusion

Conditions
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Critical Illness, Fluid Responsiveness

Intervention / Treatment
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* Diagnostic Test: fluid responsiveness assessment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: mechanically ventilated patients with circulatory failure, who are monitored with PiCCO and need fluid responsiveness assessment Exclusion Criteria: contraindication for the volume administration (hydrostatic pulmonary edema or other evidence of fluid overload) contraindication for PLR test (e.g. after trauma) lack of possibility to examine the carotid arteries bilateral carotid surgery in the past bilateral anatomical defects of the carotid arteries unstable cardiac rhythm (e.g. atrial fibrillation)

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Acute circulatory failure<br>Mechanically ventilated patients with acute circulatory failure, monitored with PiCCO method, who need fluid responsiveness assessment. | Diagnostic Test: fluid responsiveness assessment<br>* During the procedure, the investigator will be imaging one of the carotid arteries with ultrasound. In expiratory phase, four sets of three video loops will be recorded: before and after PLR and then before and after fluid challenge. There also will be noted hemodynamic parameters measured with PiCCO monitor. The fluid challenge is defined as administration of 500ml of crystalloid in less than 10 minutes. Later, another investigator, who will be blinded to other data, will measure the maximal and minimal diameter of CCA in each loop. The measurements will be averaged and eventually two values (maximal an minimal) from each set will be obtained.<br>* Other names: fluid challenge;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in the diameter of the common carotid artery | The diameter will be measured with ultrasound | 1 minute after PLR test and 1 minute after fluid challenge | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation the value of changes in the diameter of CCA as the predictor of fluid responsiveness. | The changes in the diameter of CCA will be compared with the changes in cardiac output measured with PiCCO method. | 1 minute after PLR test and 1 minute after fluid challenge | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Passive Leg Raise, Fluid Challenge, Common carotid artery