Restrictive vs Goal Directed Fluid Therapy During Hepatobiliary Surgery

Study Overview
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Brief Summary
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Restrictive fluid management is usually the current standard practice for patients undergoing liver surgery. The general idea is to maintain a low central venous pressure in order to decrease blood loss and improve the quality of the surgical field. However, this strategy , considered as rather restrictive, can be associated with patient's harm, mainly acute kidney injury. Today, Goal directed fluid therapy (GDFT) is a well accepted strategy to optimize fluid administration in patients undergoing major surgery which aimed to maintain normovolemia without being too liberal. The goal of this randomized controlled trial is to compare these two strategies on Urethral Perfusion index measured with a new IKORUS UP probe (Foley catheter made smarter with embedded photoplethysmographic sensing technology).

Detailed Description
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Restrictive fluid administration aiming at maintaining a low central venous pressure (low-CVP) during liver surgery has always been considered as a gold standard strategy because it decrease blood loss and improve the quality of the surgical field. However, this strategy , rather restrictive, can be associated with patient harm (mainly AKI). Today, Goal directed fluid therapy (GDFT) is a well accepted strategy to optimize fluid administration in patients undergoing major surgery.Some studies have shown that this strategy is feasible for such patient population. There is currently a lack of data supporting the advantage of one strategy over the other in this patient population.While a restrictive fluid strategy can advantage the surgeon, it can also disadvantage the patient as in order to avoid hypotension, vasopressors administration is required. If the patient is hypovolemic, such strategy may cause acute kidney injury. The goal of this randomized controlled trial is to compare these two strategies on Urethral Perfusion index measured with a new Foley catheter with embedded photoplethysmographic sensing technology). This new technology allows for continuous and easy monitoring of urethral tissue perfusion The investigators hypothesis is that patients in the GDFT group will have better Urethral Perfusion index (uPI) during surgery (via a better cardiac blood flow optimization) compared to patients in the restrictive (low CVP) group.

Official Title
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Impact of Goal-directed Versus Restrictive Fluid Therapy on Urethral Tissue Perfusion in Hepatobiliary Surgery: A Prospective Randomized Controlled Trial

Conditions
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Liver Surgery

Intervention / Treatment
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* Procedure: GDFT
* Procedure: LOW CVP (restrictive group)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: -All adults patients undergoing a liver surgery and equipped with a cardiac output monitoring device Exclusion Criteria: -Atrial fibrillation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 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
Interventional Model Description: Single center randomized controlled superiority study
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Low CVP group (restrictive group)<br>Standard practice: the goal is to keep the CVP < 7 mmHg during surgery. Baseline of crystalloid of 2ml/kg/h max in all patients. EV 1000 monitoring device (Edwards Lifesciences, Irvine, USA) will be used but values will be blinded to the anesthesiologist in charge of the patient. Mean Arterial pressure (MAP) should be kept over 65mmHg during surgery (standard practice) with continuous norepinephrine infusion Additionnal fluid administration is given to the patient at the end of the surgery (standard practice) UPi is blinded in all groups | Procedure: LOW CVP (restrictive group)<br>* Goal = CVP < 7mmHg and only 2 ml/kg/h max during surgery.<br>|
| Experimental: GDFT group<br>The goal is to keep stroke volume variation below 13% during surgery with mini fluid challenge of 100 ml of balanced crystalloid using the monitoring device (Edwards Lifesciences, Irvine, USA). Of course, the values will not be blinded to the anesthesiologist in charge of the patient. All patients have a baseline crystalloid: 2ml/kg/h and mini fluid challenges per 100 ml as described above. Mean Arterial pressure (MAP) should be kept over 65mmHg during surgery (standard practice) with continuous norepinephrine infusion UPi is blinded in all groups | Procedure: GDFT<br>* The titration of fluid will be based on stroke volume variation. The goal is to maintain this variable < 13% during surgery with multiple mini fluid challenge of 100 ml of balanced crystalloid.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Urethral Perfusion index | average of the Urethral Perfusion index values | during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Urethral Perfusion index | average of the Urethral Perfusion index values during the first 15-30 minutes of the surgery | during surgery | 
| Urethral Perfusion index | average of the Urethral Perfusion index values during the last 15-30 minutes of the surgery | during surgery | 
| Amount of fluid during surgery | amount of crystalloid received during the surgery | during surgery | 
| Amount of vasopressors | amount of vasopressors received during surgery | during surgery | 
| Stroke volume index | average of stroke volume index during surgery | during surgery | 
| stroke volume variation | average of stroke volume variation during surgery | during surgery | 
| cardiac index | average of cardiac index during surgery | during surgery | 
| incidence of acute kidney injury | incidence of acute kidney injury measured with the KDIGO classification | At postoperative day 7 | 
| length of stay in the hospital | length of stay in the hospital | Postoperative day 30 | 
| Incidence of postoperative complications | Incidence of postoperative complications | Postoperative day 30 |