Fluid Investigation Colloid vs Crystalloid Reg. Renal Hemodynamics and Function

Study Overview
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Brief Summary
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Comparing the effects of crystalloid versus colloid fluid resuscitation in CABG patients postoperatively regarding renal blood flow, glomerular filtration rate and renal oxygen demand.

Detailed Description
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Due to blood loss and SIRS postoperative hypovolemia is a usual feature after CABG surgery. Substantial controversy persists regarding the best choice of fluid to be used for resuscitation in this setting regarding renal function and oxygen supply-demand matching. In our study we aim to investigate differences in functional renal parameters by dividing patients postoperatively in two groups, substituted either with crystalloid fluid, Ringer-Acetat, 20 ml/kg or colloid, HES 6% (130/0,4) 10 ml/kg under 20 minutes. Central and renal hemodynamics will be measured before (baseline) and after fluid administration by blood sampling and thermodilution in both pulmonary artery catheter and renal vein catheter. Measurement endpoints will mainly consist of central hemodynamics, renal blood flow, GFR and renal oxygen extraction rate which we aim to compare between groups.

Official Title
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Colloid vs Crystalloid Infusion Postoperative in CABG Patients Regarding Renal Hemodynamics and Function

Conditions
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Renal Impairment

Intervention / Treatment
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* Drug: crystalloid
* Drug: colloid


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: elective fast track CABG patients, postoperative Exclusion Criteria: hemodynamic instability preoperative renal impairment major postoperative bleeding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: crystalloid<br>crystalloid fluid administration, Ringer-acetat 20ml/kg under 30 minutes | Drug: crystalloid<br> <br> * Other names: NaCl;|
| Experimental: colloid<br>colloidal fluids administration, HES 6% (130/0,4) 7ml/kg under 30 minutes | Drug: colloid<br> <br> * Other names: Tetraspan;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline and differences inbetween groups in glomerular filtration rate, measured at different timepoints | GFR measured by thermodilution and blood- and urine sampling baseline1 (0min), baseline2 (+30min), timepoint1 (+65min), tp2 (+85min), tp3 (+105min), tp4 (+125min) | 125min after baseline-measures | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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elective CABG, renal impairment, GFR, renal blood flow, colloid, crystalloid, thermodilution technique, oxygen supply demand