Echo FLOW Versus (Non-)Invasive Haemodynamics

Study Overview
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Brief Summary
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Rationale: Diligent fluid management is instrumental to improve postoperative outcome, cost and quality of care. Objective: To determine the accuracy of brachial, femoral and carotid blood flow measurement with ultrasound compared to intermittent transpulmonary thermodilution cardiac output measurement, invasive and non-invasive pulse-contour analysis. Study design: Observational study - Prospective clinical non-intervention measurement study. Study population: Adult ASA 1-2 patients, scheduled for open upper GI surgery Intervention (if applicable): Not applicable. We will perform non-invasive ultrasound measurements of the femoral, carotid and brachial blood flow right before induction and under anaesthesia. Main study parameters/endpoints: Femoral, carotid and brachial blood flow determined by ultrasound and blood flow variation and the accuracy compared to transpulmonary thermodilution cardiac output, stroke volume variation, and pulse-contour analysis derived cardiac output (invasive or non-invasive) at the following time points during surgery; (limited for femoral site as it cannot be measured during surgery): (1) before induction of anaesthesia, (2) after induction, (3) 15 minutes after start of surgery, (4) before and (5) after (1-2 minutes) a fluid bolus, (6) before and (7) after start of vasopressors, (8) before and (9) after Trendelenburg position and (10) after surgery before end of anaesthesia (figure 1). A fluid bolus will be performed as part of standard care (goal-directed fluid therapy). The vasopressor and Trendelenburg position time points are optional measurements. We will also measure (continuous) invasive femoral blood pressure (SBP, DBP, MAP), non-invasive blood pressure, SVV, central venous pressure (when available), heart rate, SpO2, PFI, etCO2.

Official Title
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The Accuracy of Ultrasound Derived Carotid, Femoral and Brachial Artery Compared to Conventional Intra-vascular Methods Flow-related Parameters

Conditions
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Cardiac Output, Low, Cardiac Output, High

Intervention / Treatment
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* Diagnostic Test: carotid blood flow measurement with ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elective open GI surgery Invasive arterial blood pressure monitoring Informed consent Exclusion Criteria: Significant stenosis > 30% or abnormal anatomy of aortic, femoral, carotid or brachial artery Cerebrovascular accident Atrial fibrillation COPD stage 3-4 Lobectomy / pneumectomy Active pneumonia Cardiac failure Severe heart valve regurgitation or stenosis Not able to measure brachial or carotid artery blood flow during surgery Contra-indications for femoral arterial catheter placement (e.g., vascular graft)

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 |
| --- | --- |
| Patients undergoing major upper abdominal surgery<br>major open upper abdominal surgery eg pancreatic, liver surgery | Diagnostic Test: carotid blood flow measurement with ultrasound<br>* carotid blood flow measurement with ultrasound vs transpulmonary thermodilution calibrated continuous cardiac output measurements<br>* Other names: transpulmonary thermodilution calibrated continuous cardiac output measurements;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiac output | blood flow determined by ultrasound and the accuracy compared to transpulmonary thermodilution calibrated continuous cardiac output | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiac output change | Change in blood flow compared to change in cardiac output | change from baseline cardiac output 1 minute after intervention (fluid challenge, vasopressor administration, or Trendelenburg) |