Licentiate Dissertation in Medical Science

4 ORIGINAL PAPERS 5 ABBREVIATIONS 6 INTRODUCTION 7 Marker substances for GFR 8 Endogenous markers 8 Exogenous markers 8 Clearance techniques for determination of GFR 9 Continuous infusion method 9 Single injection method 10 Single injection, single sample methods 12 AIMS OF THE STUDY 16 MATERIALS AND METHODS 17 Materials 17 Cr-EDTA and Tc-DTPA analysis 18 Iohexol analysis 19 Derivation of a single sample plasma clearance formula by the mean sojourn time approach 19 Statistics 22 RESULTS 23 Clearance according to Brøchner-Mortensen’s one-compartment model compared to Sapirstein’s two-compartment model 23 Derived single sample formulas by the mean sojourn time approach 24 Cr-EDTA clearance (Paper I) 24 Iohexol clearance (Paper II) 26 Low clearance formula (Paper II and III) 26 Test of the derived single sample formulas 27