Optimization of Hepatic Hemodynamics During Liver Surgery

Study Overview
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Brief Summary
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The purpose of this study is to determine if vasopressin and nitroglycerin in combination will affect hepatic hemodynamics, in the setting of liver surgery.

Detailed Description
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The patients in this study (undergoing elective liver resection) will be anesthetized according to routine practice in our hospital. A radial arterial catheter and a central venous catheter will be inserted, as well as a femoral arterial catheter for Picco monitoring. After the dissection phase, catheters will be inserted in the portal and hepatic veins by the surgeon. Base line data (HR, CVP, MAP, CO from thermodilution, portal and hepatic venous pressure, blood gases from radial artery, vena cava superior, hepatic vein and portal vein) will be obtained twice, with 10 minutes of steady state in between. An infusion of vasopressin 4,8 U/h will then be started and continued for 20 minutes. Data will be collected again, and an infusion of nitroglycerine (to a target of MAP 60 mmHg) will be added. After 5 minutes of steady MAP 55-65, the last set of data is collected. 12 Patients will be recruited, and the total data collection is estimated to be completed and assessed after six to nine months.

Official Title
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Effects of Vasopressin and Nitroglycerine in Combination on Splanchnic Blood Flow, and on Hepatic and Portal Venous Pressures in Liver Resection

Conditions
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Portal Blood Pressure, Liver Surgery, Hepatic Hemodynamics

Intervention / Treatment
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* Drug: vasopressin + nitro


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients within ASA-class I-II scheduled for open liver resection Exclusion Criteria: ASA-class III and IV, more than 2 medications for hypertension, BMI > 35, technical difficulties with insertion av catheters, extensive surgery.

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: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: vasopressin + nitro<br>vasopressin + nitroglycerin in simultaneous infusion | Drug: vasopressin + nitro<br>* vasopressin infusion 4,8 U/h for 20 minutes, thereafter nitroglycerine infusion to a MAP of 60 for 5 minutes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Portal and hepatic venous flow after vasopressin and nitroglycerine infusion |  | six - nine months | 
| Pressure in the hepatic and portal veins after vasopressin and nitrovasopressin infusion |  | six - nine months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| lactate in the splanchnic circulation |  | six-nine months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vasopressin, nitroglycerine, portal pressure, portal flow