Closed-loop Fluid Administration System: Pilot Study to Evaluate Feasibility

Study Overview
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Brief Summary
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The investigators want to test during anesthesia the feasibility of a closed-loop automated fluid replacement system using cardiac output monitoring as the input value.

Detailed Description
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The optimization of the cardiac output is an important goal during anesthesia to decrease the postoperative morbidity, mortality and the care costs. We want to test if the closed-loop fluid administration is feasible. Two groups will be compared. In all cases: anesthesia will be provided by a closed-loop which aim is to maintain bispectral index between 40 and 60 using propofol and remifentanil. This method permits to have similar depths of anesthesia in all cases. cardiac output will be continuously monitored by LidCO. In one group, fluid replacement is decided by the physician; in the other, fluid replacement is automated using a closed-loop system.

Official Title
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Automated Administration of Fluid Administration Thanks to Hemodynamic Parameters and Cardiac Output During General Anesthesia

Conditions
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Anesthesia

Intervention / Treatment
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* Drug: Open loop
* Device: Closed-loop


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients aged 18-75 years Scheduled for abdominal surgery under general anesthesia and requiring an invasive arterial blood pressure monitoring Consenting to participate in the study Exclusion Criteria: Pregnant, breast feeding women Allergy Pacemaker Psychiatric disease, dementia, brain disease Contraindication to hydroxyethyl starch Inability to measure pulse pressure variability : arrhythmia, spontaneous breathing, or tidal volume < 7 ml/Kg

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Open loop<br>fluid replacement (hydroxyethyl starch 130/0.4) is decided by the physicians according to continuous cardiac output measured by LidCO rapid device | Drug: Open loop<br> <br> * Other names: fluid replacement by Voluven(hydroxyethyl starch 130/0.4);|
| Experimental: Closed-loop<br>Fluid replacement is automated. An algorithm has been developed ; the input value is continuous cardiac output measured by LidCO rapid device; the computer steers iv infusion of hydroxyethyl starch 130/0.4. | Device: Closed-loop<br> <br> * Other names: fluid replacement by Voluven (hydroxyethyl starch 130/0.4) is automated (closed-loop);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean cardiac output index during the surgery |  | One day after anesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time before reaching maximizing cardiac output |  | One day after anesthesia | 
| Volume of fluid replacement during surgery |  | One day after anesthesia | 
| cardiac index during the surgery | Maximum and minimum values during the surgery | One day after anesthesia | 
| arterial hypertension | Number of events treated | One day after anesthesia | 
| Dysfunction of the closed-loop fluid device |  | One day after anesthesia | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anesthesia, Fluid administration, Closed-loop