Consistency of Carotid Doppler Blood Flow and Thermodilution Technique

Study Overview
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Brief Summary
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Currently, the gold standard method to estimate CO is the thermodilution technique, pulmonary artery catheter (PAC) and PiCCO system included, however, the invasiveness and complexity of the thermodilution technique have limited their usefulness in many clinical scenarios. By measuring the carotid blood flow, continuous carotid doppler technique has been reported to noninvasively estimate cardiac output (CO) and other parameters related to cardiac contractility and fluid status in various cardiovascular disorders. However, to the best of our knowledge, few study has been reported to evaluate the consistency of this technique in cardiac surgery patients. The aim of this study is to evaluate the tracking ability of CO changes measured by continuous carotid doppler technique in cardiac surgery patients, use the thermodilution technique as the referenced.

Official Title
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The Consistency of Tracking Changes of Cardiac Output by Carotid Doppler Blood Flow and Thermodilution Technique in Cardiac Surgery Patients

Conditions
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Cardiac Surgery

Intervention / Treatment
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* Behavioral: passive leg raising
* Drug: Dobutamine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult cardiac surgery patients with thermodilution technique monitoring mechanical ventilation Exclusion Criteria: life threatening arrhythmia severe valve regurgitation left ventricular ejection fraction less than 30% patients with mechanical circulatory support

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: cardiac surgery patients with thermodilution technique monitoring<br> | Behavioral: passive leg raising<br>* transfer a patient from semi-recumbent position to supine position with a 45° leg lifting<br>Drug: Dobutamine<br>* infusion dobutamine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| cardiac output by thermodilution method | measuring cardiac output using thermodilution method | 5 minutes after the patients was sedated | 
| cardiac output by continuous carotid doppler blood flow | measuring cardiac output using continuous carotid doppler blood flow | 5minutes after the patients was sedated | 
| cardiac output by thermodilution method | measuring cardiac output using thermodilution method | 2 minutes after passive leg raising | 
| cardiac output by continuous carotid doppler blood flow | measuring cardiac output using continuous carotid doppler blood flow | 2 minutes after passive leg raising | 
| cardiac output by thermodilution method | measuring cardiac output using thermodilution method | 15 minutes after termination of passive leg raising | 
| cardiac output by continuous carotid doppler blood flow | measuring cardiac output using continuous carotid doppler blood flow | 15 minutes after termination of passive leg raising | 
| cardiac output by thermodilution method | measuring cardiac output using thermodilution method | 30 minutes after dobutamine infusion | 
| cardiac output by continuous carotid doppler blood flow | measuring cardiac output using continuous carotid doppler blood flow | 30 minutes after dobutamine infusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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carotid doppler; hemodynamic