Intraoperative Hypovolemia and Fluid Therapy

Study Overview
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Brief Summary
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Postoperative organ dysfunction severely affects the prognosis of surgical patients. Despite several trials evaluating restrictive or liberal fluid strategies, the ideal fluid replacement strategy remains controversial. Owing to the risk of altered tissue perfusion, a key trigger of organ dysfunction, the purpose of this study was to compare the influence of restrictive and liberal fluid regimens, using a goal-directed approach, on hypovolemia and postoperative organ dysfunction.

Detailed Description
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Despite several trials evaluating restrictive or liberal fluid strategies, the ideal fluid replacement strategy remains unanswered. Although recent studies suggest that intraoperative fluid restriction may reduce postoperative morbidity and promote faster recovery, extrapolation to individual patients remains difficult. Indeed, whether fluid overload may expose tissue to oedema, impairing oxygenation and wound healing, fluid restriction may, conversely, expose to hypovolemia, which occurs frequently during abdominal surgery, leading to tissue hypoperfusion and organ dysfunction. To date, the restrictive and liberal fluid substitution strategies have not been compared using a goal-directed approach. In addition, recent data suggest that targeting early indicators of hypoperfusion, such as central venous oxygen saturation (ScvO2), which reflects the oxygen delivery/consumption relationship, may be important in the management of patients undergoing major surgery. No data are available on the effects of intraoperative fluid volume replacement strategy on ScvO2 modifications. The purpose of this study is first to evaluate the influence of restrictive and liberal fluid replacement strategies on both hypovolemia and postoperative organ dysfunction using an oesophageal doppler goal-directed approach (with goal = peak aortic velocity variation and stroke volume optimization) during major abdominal surgery. The second objective is to investigate the effects of fluid loading on ScvO2 modifications.

Official Title
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Restrictive Versus Liberal Intraoperative Goal-directed Fluid Management During Major Abdominal Surgery:a Prospective Randomized Study

Conditions
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Hypovolemia, Organ Dysfunction

Intervention / Treatment
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* Other: restrictive and liberal fluid therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Major intraabdominal surgery Exclusion Criteria: Age < 18 years Pregnancy Body mass index > 35 kg/m2 Emergency surgery Coagulopathy Sepsis or Systemic inflammatory response syndrome (SIRS) Hepatic failure (prothrombin ratio < 50%, factor V < 50%) Contraindication for epidural analgesia

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

Allocation: Randomized
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: restrictive fluid<br>Restrictive fluid administration: 6 ml kg-1 h-1 of crystalloids (lactated Ringer's solution) | Other: restrictive and liberal fluid therapy<br>* In both group, when hypovolemia is suspected (peak aortic velocity variation > 13%): fluid bolus (hydroxyethyl starch 130/0.4/6%) according to a predefined algorithm designed to maintain peak aortic velocity < 13% and no further increases in SV<br>|
| Experimental: liberal fluid<br>Liberal fluid administration: 12 ml kg-1 h-1 of crystalloids (lactated Ringer's solution) | Other: restrictive and liberal fluid therapy<br>* In both group, when hypovolemia is suspected (peak aortic velocity variation > 13%): fluid bolus (hydroxyethyl starch 130/0.4/6%) according to a predefined algorithm designed to maintain peak aortic velocity < 13% and no further increases in SV<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of intraoperative hypovolemia |  | intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative organ failure postoperative complications (included anastomotic leak, perianastomotic abscess) |  | postoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Intraoperative fluid, Monitoring, Oesophageal Doppler, Abdominal surgery, major abdominal surgery