Mini-fluid Challenge in Predicting Fluid Responsiveness During Prone Position Spine Surgery

Study Overview
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Brief Summary
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Perioperative fluid management is crucial for patients' outcome. Muller et al developed a Mini-fluid challenge method  to predict fluid responsiveness and the efficacy. The investigators design the study to investigate the effectiveness of mini-fluid challenge test in prone position surgery.

Detailed Description
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Perioperative fluid management is crucial for patients' outcome. Series of studies have indicated that adequate fluid management optimizes the cardiac out put, improves tissue perfusion, thus decrease the risk of postoperative morbidity. Muller et al developed a Mini-fluid challenge method  to predict fluid responsiveness and the efficacy. To the best of our knowledge, the efficacy of the test was not discussed in the perioperative care in prone position surgery. The investigators design the study to investigate the effectiveness of mini-fluid challenge test in prone position surgery.

Official Title
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The Effectiveness of Mini-fluid Challenge in Predicting Fluid Responsiveness During Prone Position Spine Surgery

Conditions
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Anesthesia

Intervention / Treatment
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* Other: Mini-fluid challenge


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: meet both of Patients receiving scheduled prone position spine surgery BMI 18.5 30 kg.m-2 Exclusion Criteria: age younger then 20 yrs or elder than 80 yrs pregnant women patients in intensive care units patients with the underlying disease including respiratory failure(FEV1/FVC < 70 % and FEV1 < 50%), heart failure(NYHA score =III、IV), kidney failure(eGFR< 60 ml.min-1.1.73m-2), liver failure patients with ongoing infection patients allergic to voluven

Ages Eligible for Study
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Minimum Age: 20 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: Mini-Fluid Challenge arm<br>Fluid challenge test will be presented after induction of anesthesia at a steady state. Fluid challenge test includes 2 components: 100 ml colloid infusion in 1 min followed by 400 ml colloid infusion in 14 mins. Hemodynamic parameter after 1 minute of the end of the 1st and 2nd colloid infusion bolus will be collected. Applied colloid: hydroxyethyl starch | Other: Mini-fluid challenge<br>* Mini-fluid challenge test with 100mL colloid infusion in 1 min<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of cardiac index after fluid loading | interpretate the correlation of mini-fluid challenge and conventional fluid challenge | 3hr | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| pulse pressure variation(PPV) | interpretate the correlation of PPV and conventional fluid challenge | 3hr |