COMPARISON OF CREATININE CLEARANCE ESTIMATION METHODS IN PATIENTS WITH TRAUMA

The abilities of a modified Cockcroft-Gault equation and the standard equation to estimate creatinine clearance (CL(alpha)) in trauma patien ts were compared. The medical records of patients with stable renal fu nction who had been treated for trauma and had had a 24-hour urine col lection for creatinine measurement were reviewed. Creatinine concentra tions in urine and serum were used to calculate the actual CL(alpha), which was normalized to 1.73 sq m. CL(alpha) was estimated by the modi fied equation (which normalized body weight to 72 kg) and by the stand ard equation using ABW, IBW, and dosing body weight (DBW). Values deri ved with the standard equation were normalized to 1.73 sq m. The predi ctive performances of the modified and standard equations in estimatin g the actual CL(alpha) were then compared. Fifty patients were enrolle d. The standard equation using IBW or DBW produced estimates that diff ered significantly from the actual CL,. The modified equation and the standard equation using ABW did not differ significantly in bias or pr ecision, but both were significantly less biased than the standard equ ation using IBW or DBW. The only significant difference among equation s in precision was between the modified equation (the more precise) an d the standard equation using IBW. There were no clinically significan t differences among methods in gentamicin dosing simulations. The modi fied Cockcroft-Gault equation can be used to estimate Cl-alpha in trau ma patients with stable renal function.