Estimation of Creatinine Clearance in Patients with Unstable Renal Function, without a Urine Specimen

Abstract

Background: There is a significant need to estimate creatinine clearance easily in acutely ill patients with unstable renal function, who have rapidly changing serum creatinine values and who need careful individualization of drug dosage, all without the problems associated with having to collect the traditional carefully timed urine specimen. Method: The daily change in the total amount of creatinine is the difference between its production and excretion. Production is estimated based on studies by others, using many carefully timed urine specimens. Daily creatinine production is related both to age and to the serum creatinine concentration. Urinary excretion of creatinine is equal to creatinine clearance times the average of a pair of timed serum creatinine concentrations, times the duration of the collection (usually 24 h). Results: Good correlation was found between conventional measured creatinine clearances and the estimated values. The estimates had a precision essentially equal to that of the traditional method. Conclusions: One can now estimate the creatinine clearance which makes serum creatinine change from an initial concentration at one stated time to another concentration at another stated time, for a patient of a stated age, gender, height and weight, without requiring a urine specimen. This method has been incorporated into software to perform the calculations easily and rapidly, and has been integrated into the USC*PACK PC programs for planning, monitoring and adjusting individualized dosage regimens of drugs.

Acute kidney disease and renal recovery: consensus report of the Acute Disease Quality Initiative (ADQI) 16 Workgroup

“…The Jelliffe equation for unstable kidney function, which is calculated on the basis of the volume of distribution and creatinine kinetics rather than steady state parameters such as body weight or age, correlated well with CCr in a small study of 12 patients in the ICU 33,34 . The kinetic eGFR, which similarly to the Jelliffe equation, estimates GFR on the basis of the creatinine kinetics has shown promise in renal transplant recipients, but should be validated in other cohorts such as hospitalized patients with native kidneys 35 .…”

Variability in Trough Total and Unbound Teicoplanin Concentrations and Achievement of Therapeutic Drug Monitoring Targets in Adult Patients with Hematological Malignancy

“…MDRDa and MDRD had the lowest bias. CG-TBW and the Jelliffe equation (JEL) (25) had the highest precision. Accuracy, in terms of the highest percentage of estimates within 30% of the measured CL CR , was the highest for JEL and CG-TBW.…”

Five-year experience with donation after cardiac death kidney transplantation in a Canadian transplant program: Factors affecting outcomes

“…DGF was defined as the need for dialysis in the first week post-transplant, while slow graft function (SGF) was defined as serum creatinine >265 µmol/L on day 5, without a need for dialysis. 4 Creatinine clearance was calculated using the CockcroftGault equation (for stable creatinine) or the Jeliffe equation 5 for non-steady-state creatinine, such as one would expect in the first postoperative week.…”