Analytical and clinical performance of three hand-held point-of-care creatinine analyzers for renal function measurements prior to contrast-enhanced imaging.

BACKGROUND: As iodine-based contrast can cause deterioration of renal function in patients with impaired kidney function, guidelines advise to measure creatinine and calculate estimated glomerular filtration (eGFR) prior to administration. Point-of-care (POC) devices seem an attractive alternative to central laboratory testing but uncertainty regarding analytical and clinical comparability remains. METHODS: This study compared three POC devices, i-STAT (Abbott), StatSensor (Nova) and epoc (Siemens) with a central laboratory method (enzymatic creatinine, Siemens Vista 1500 platform). 120 patients were included and underwent simultaneous finger prick capillary blood analysis on the StatSensor and heparine whole blood analysis on StatSensor, i-STAT and epoc. RESULTS: All POC devices generated results which showed considerable variability around the creatinine value of the reference standard, with StatSensor having the widest (-1,12-1,11 mg/dL) and epoc the tightest (-0,49-0,49 mg/dL) 95% limits of agreement. I-STAT showed the highest clinical concordance with the reference standard (Kappa: 0,94) and had the smallest average analytical error (6%) for creatinine and eGFR compared to the reference standard, meeting the predefined criteria of 8,87% and 10%, respectively. Epoc only met criteria for eGFR. StatSensor did not meet any of the criteria. CONCLUSIONS: I-STAT and epoc were, analytically and clinically, the most performant POC devices included in this study but showed to be less user-friendly. StatSensor did not meet any of the error criteria, neither for creatinine nor for eGFR measurements, and gave more clinical major classification errors. However, it proved to be more user-friendly compared to the other POC devices.