Iohexol Clearance in Critically Ill Patients With Augmented Renal Creatinine Clearance

Study Overview
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Brief Summary
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Evaluation of glomerular filtration rate using iohexol plasma clearance in critically ill patients with augmented renal creatinine clearance

Detailed Description
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Single center study in ICU patients with augmented renal clearance comparing glomerular filtration rate (GFR) as measured by iohexol plasma clearance to that measured by creatinine clearance. Primary objective is to compare the GFR estimates made by iohexol plasma clearance (as reference method) and creatinine clearance using Bland-Altman method. Secondary objective are to compare GFR as measured by iohexol plasma clearance to that calculated with the most commonly used renal clearance estimating formulas (Cockcroft and Gault, MDRD and CKD-EPI ), evaluate clinical determinant of the observed differences and evaluate determinants of extracellular volume.

Official Title
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Evaluation of Glomerular Filtration Rate Using Iohexol Plasma Clearance in Critically Ill Patients With Augmented Renal Creatinine Clearance

Conditions
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Augmented Renal Clearance, Critically Ill

Intervention / Treatment
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* Drug: Iohexol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ICU patient 24h Creatinine clearance >130ml/min/1.73m2 Urinary catheterization Affiliation to a social security scheme Exclusion Criteria: Pregnancy CT-scan with contrast media infusion the day of inclusion Documented allergy to contrast media Patient under guardianship / curatorship Patient benefiting from the State Medical Assistance

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Critically ill patients with augmented renal clearance<br>ICU patients with estimated renal clearance over 130ml/min/1.73m2 | Drug: Iohexol<br>* Intravenous injection of 5 ml of iohexol (Omnipaque) to calculate the glomerular filtration rate (area under the curve). Blood samples (2 ml) and urine (2 ml minimum) are to be collected for the determination of iohexol clearance at the following time points: pre-dose, 5 minutes, and 1, 2, 3, 4, 5, 6 hours post dose.<br>* Other names: Omnipaque;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| GFR obtained by the iohexol clearance technique | GFR as measured by iohexol plasma clearance to evaluate its concordance, by the Bland and Altman method, with that obtained by measuring the clearance of creatinine. | 6 hours | 
| GFR obtained by the creatinine clearance technique | GFR as measured by creatinine plasma clearance | 6 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| GFR calculated using the Cockroft-Gault equation | Estimation of GFR using the Cockroft-Gault method based on the serum creatinine clearance measured on the day of intervention and the patient's weight of the day, and the agreement with the GFR measured by the iohexol clearance | 6 hours | 
| GFR calculated using the Modification of diet in renal disease (MDRD) formula | Estimation of GFR using MDRD method based on the serum creatinine clearance measured on the day of intervention and the patient's weight of the day, and the agreement with the GFR measured by the iohexol clearance | 6 hours | 
| GFR calculated using the Chronic Kidney Disease - Epidemiology Collaboration (CKD-EPI) equation | Estimation of GFR using CKD-EPI method based on the serum creatinine clearance measured on the day of intervention and the patient's weight of the day, and the agreement with the GFR measured by the iohexol clearance | 6 hours | 
| Plasmatic Levetiracetam dosing | To detect underdosing and risk of therapeutic failure of Levetiracetam | 6 hours | 
| Plasmatic Vancomycin dosing | To detect underdosing and risk of therapeutic failure of Vancomycin | 6 hours | 
| Plasmatic Piperacillin dosing | To detect underdosing and risk of therapeutic failure of Piperacillin | 6 hours | 
| Plasmatic Cefotaxim dosing | To detect underdosing and risk of therapeutic failure of Cefotaxim | 6 hours | 
| Plasmatic Aminoglycoside dosing | To detect underdosing and risk of therapeutic failure of Aminoglycoside | 6 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Iohexol, Augmented renal clearance, Intensive Care Unit