Effect of Sevoflurane and Propofol on Hepato-splanchnic Pressure and Flow During Hepatobiliary Surgery

Study Overview
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Brief Summary
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Blood loss in hepatobiliary surgery is correlated with an increase in postoperative complications (e.g. transfusion related lung injury and tumor recurrence) and reduced longterm survival. To reduce morbidity and mortality in hepatobiliary surgery, modulation of the hepato-splanchnic blood flow and pressure is used. In liver surgery pharmacological modulations are widely used to prevent blood loss. For pharmacological modulation central venous pressure is commonly used to reduce the pressure in the inferior vena cava, however little is known about pharmacological effect on blood flow in the hepatic artery and portal vein. The modulation of the hepato-splanchnic blood flow can also play an important role, not only for prevention of blood loss but also for survival of the organs (e.g. ischemic injury due to low flow). Volatile anesthetics induce a dose-dependent reduction of the hepato-splanchninc blood flow. Propofol however, increases hepatic blood flow when compared with volatile anesthetics. Pharmacological modulation of hepato-splanchnic bloodflow with anesthetics such as sevoflurane or propofol can play an important role in modulation of ischemia/reperfusion injury and survival of organs. The aim of the study is to determine and to compare the effect of sevoflurane versus propofol on hepatosplanchnic pressure and hepato-splanchnic blood flow during hepatobiliary surgery.

Detailed Description
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All patients receive standardized anesthesia care for hepato-biliary surgery according to the existing anesthesia protocol. The type of anaesthesia will be randomized : propolipid (TIV) or sevorane(inhalation). At designated times, hemodynamic variables will be recorded. These will include: HF (/min) CVP (mmHg), MAP (mmHg) CI (L/min.m2) PPV (pulse pressure variation). Hemodynamic measurement will be done using PiCCO catheter. The hemodynamic measurements will be compared and related to hepato-splanchnic blood flow and pressure measurements performed by the surgeon: Flow v. porta Flow art. hepatica Pressure v. porta Pressure v. cava The flow measurements will be done using ultrasound transit time ﬂow measurements TTFM (Medi-Stim AS, Oslo, Norway). At the same time pressure measurements will be obtained in portal vein and caval vein using a 25-gauge needle which is directly placed in the vein. Both flow and pressure will be simultaneously recorded (VeriQ 4122, Medi-Stim AS, Oslo, Norway). Both measurements will be done during apnea to minimize the effect of ventilation on pressure & flow. Flow values will be expressed in ml per minute, pressure values will be expressed in mmHg.

Official Title
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Effect of Sevoflurane and Propofol on Hepato-splanchnic Pressure and Flow During Hepatobiliary Surgery

Conditions
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General Anesthesia

Intervention / Treatment
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* Drug: Propofol Fresenius
* Drug: sevorane


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult ≥ 18 years (Female or Male) ASA I - II - III Able to comprehend, sign and date the written informed consent document to participate in the clinical trial. Scheduled for hepato-biliary surgery. Exclusion Criteria: Allergy for the medication Renal insufficiency (SCr > 2 mg/dl) Severe heart failure (EF < 25%) Hemodynamic instable patients Arterial fibrillation Sepsis BMI > 40 Severe coagulopathy (INR > 2) Thrombocytopenia (< 80 x 10³ /µL) History of severe postoperative nausea & vomiting

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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group P<br>Group P : Propolipid 1% dose : variable to keep BIS between 40 and 60 | Drug: Propofol Fresenius<br>* Propolipid 1% : IV<br>|
| Experimental: Group S<br>Group S : Sevoflurane dose : variable to keep BIS between 40 and 60 | Drug: sevorane<br>* sevorane Quick fill (sevoflurane) : inhalation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in blood flow in hepatic artery and main portal vein | flow/pressure measurements with echo probe and needle | From randomization until the end of the whipple surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| need of inotropic and/or vasopressor support | total dose of inotropic and vasopressor medication that were used during surgery | From start anesthesia until end of anesthesia | 
| amount of blood loss | amount of blood loss at end of surgery | From start of surgery until end of surgery | 
| amount of colloids given during surgery | total amount of colloids given during surgery | From start of surgery until end of surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hepato-splanchnic blood flow