Iohexol Clearance in Critically Ill Patients With Augmented Renal Creatinine Clearance

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.