Validation of Nicom Device to Measure Stoke Volume Variation

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the ability of NICOM (Noninvasive cardiac output monitor) to detect stroke volume variation induced by leg raising or fluid expansion during surgery

Official Title
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Validation of NICOM for the Detection of Modification of Stroke Volume

Conditions
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Anesthesia

Intervention / Treatment
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* Procedure: Volume loading
* Drug: Ringer solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing general anesthesia with an expected duration exceeding two hours gastrointestinal surgery, urological or gynecological surgery. Exclusion Criteria: Difficulty of venous access. Contraindication for the use of oesophageal Doppler Contraindication for the use of Nicom Contraindication for the use of bispectral index Pregnant or lactating women

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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low volume<br>The protocol will follow the following steps : basal measurements (heart rate, arterial pressure, stroke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) followed by passive leg rising and additional measurements (heart rate, arterial pressure, stoke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) second basal measurements (heart rate, arterial pressure, stoke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) followed by low volume loading (250 ml of Ringer solution) and additional measurements (heart rate, arterial pressure, stoke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) | Procedure: Volume loading<br>* Volume loading with Ringer Lactate<br>Drug: Ringer solution<br> <br> |
| Experimental: High volume<br>The protocol will follow the following steps : basal measurements (heart rate, arterial pressure, stroke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) followed by passive leg rising and additional measurements (heart rate, arterial pressure, stoke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) second basal measurements (heart rate, arterial pressure, stoke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) followed by low volume loading (500 ml of Ringer solution) and additional measurements (heart rate, arterial pressure, stoke volume estimated by esophageal Doppler, stoke volume estimated by Nicom) | Procedure: Volume loading<br>* Volume loading with Ringer Lactate<br>Drug: Ringer solution<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stroke volume variation | Stroke volumes measured by esophageal Doppler and by Nicom: at baseline, after leg passive rising, and after volume loading | 6 hours |