Vasodilator-induced Hypovolemia in Living Liver Donors

Study Overview
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Brief Summary
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Induced hypovolemia is known to improve surgical field during living donor hepatectomy. This procedure is conventionally guided by monitoring the central venous pressure (CVP). Stroke volume variation (SVV) is a novel method to substitute with CVP to monitor cardiac preload. The investigators try to evaluate the relationship between CVP and SVV during CVP-guided vasodilator induced hypovolemia (validation study). Then, feasibility of vasodilator induced hypovolemia using the SVV calculated from the validation study will be tested (feasibility study).

Detailed Description
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This is a 2-phases study. first phase validation study : Evaluation of the relationship between CVP and SVV during CVP-guided vasodilator induced hypovolemia second phase feasibility study : Comparison of the surgical field grade between validation study group(CVP guided group) and feasibility study group(SVV guided group)

Official Title
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Vasodilator-induced Hypovolemia in Living Liver Donors: Central Venous Pressure-guided vs Stroke Volume Variation-guided Technique

Conditions
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CVP and SVV During Living Donor Hepatectomy, Surgical Field Grade (Condition of Surgical Field; Bleeding, Tension of the IVC)

Intervention / Treatment
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* Procedure: vasodilator induced hypovolemia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult (20-60 yr) elective living liver donors Exclusion Criteria: not obtained informed consent

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: CVP<br>Central venous pressure-guided vasodilator-induced hypovolemia | Procedure: vasodilator induced hypovolemia<br> <br> * Other names: Milrinone induced hypovolemia;|
| Experimental: SVV<br>stroke volume variation-guided vasodilator-induced hypovolemia | Procedure: vasodilator induced hypovolemia<br> <br> * Other names: Milrinone induced hypovolemia;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| target value of SVV | Target value of SVV is calculated from the linear regression equation that was calculated from scatter plot made with CVP and SVV values during CVP-guided vasodilator induced hypovolemia (validation study). | during living donor hepatectomy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| surgical field | <4 point scale> Grade l: Very lax IVC and hepatic veins, minimal bleeding at resection plane, very easy to operate Grade ll: Lax IVC and hepatic veins, a little bleeding at resection plane, easy to operate Grade lll: Tense IVC and hepatic veins, appreciable bleeding at resection plane, somewhat difficult to operate Grade lV: Very tense IVC and hepatic veins, profuse bleeding at resection plane, very difficult to operate | during living donor hepatectomy | 
| use of inotropics |  | during living donor hepatectomy | 
| estimated blood loss |  | during living donor hepatectomy | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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liver donor, hepatectomy, vasodilator, central venous pressure, stroke volume variation