Agreement between serum creatinine and fingerstick creatinine measurements in adult patients admitted to the emergency department

INTRODUCTION: Critically ill patients are frequently encountered in the emergency department (ED) and requiring rapid diagnosis and treatment. It has been shown that fingerstick tests shorten examination and treatment durations in the ED. The aim of this study was to assess the agreement between fingerstick creatinine measurements and serum creatinine values obtained by laboratory enzymatic testing. METHODS: This study was conducted as a single center, prospective, observational study. 250 patients aged 18 years and over who applied to the adult emergency department between 12.12.2023 and 30.12.2023 and underwent the necessary serum biochemistry examination were included in the study. In addition to the blood biochemistry tests were requested by the patients' doctors, blood samples taken from the patients' fingertips were scanned using the i-STAT device and a creatinine cartridge. Intraclass correlation coefficient (ICC) was used to examine the consistency between serum creatinine values measured in the laboratory and fingerstick creatinine values, and the type 1 error level was set as 0.05. A graphical approach, the Bland-Altman plot was used to examine the agreement between measurements. A significance level of 0.05 was used for all comparisons. RESULTS: In this study, after exclusion of 4 patients due to kit problems, 133 patients (54.16%) were female and 113 patients (45.94%) were male. The median age was found to be 55.5. A strong agreement was found between the measured values (ICC: 0.996). Patients when analyzed among themselves in terms of admission complaints, existing diseases, age, gender, admission vital signs and glomerular filtration rates, a strong agreement was observed between fingertip creatinine and serum creatinine in each group. CONCLUSION: In conclusion, the fingerstick creatinine test may be considered for early use in patients presenting to the ED, as it is easily applicable in examination and treatment management and has strong agreement rates with laboratory values.