Comparison of Improvacuter EDTA Tube with BD Vacutainer EDTA Tube for Routine Hematological Analysis: Clinical Significance of Differences, Stability Study, and Effects of K₂ and K₃ EDTA

BACKGROUND: The type of blood collection tubes is an important pre-analytical factor that may affect test results. We compared the test results of the Improvacuter EDTA tube (Improve Medical, China) with those of the currently used BD Vacutainer EDTA tube (Becton Dickinson, USA) and investigated the effects of K₂ and K₃ EDTA additives. METHODS: Peripheral blood samples from 100 outpatients were collected into the aforementioned tubes. The samples were evaluated for 17 hematological analytes, hemoglobin A1c, and erythrocyte sedimentation rate (ESR). The results were analysed using the paired t-test for comparison. Bland-Altman plots and Passing-Bablok regressions were used for analytes with statistically significant differences in the comparison. If the differences were not within total allowable error, they were defined as clinically significant. For stability testing, the initial results were compared against those from samples preserved for 72 hours. White blood cell count, red blood cell count, platelet count, and mean corpuscular volume from both tubes were compared to ascertain the differences between K₂ and K₃ EDTA additives. RESULTS: Hematocrit, mean corpuscular volume, mean corpuscular haemoglobin concentration, and ESR showed statistically significant differences (P<0.05) between two tubes. However, these differences were not considered clinically significant. Most of the analytes presented statistically significant differences in stability test; however, they were not clinically significant either. Additionally, the differences in the hematological parameters shown in the outcome were not clinically significant, depending on the type of the EDTA additives. CONCLUSIONS: The results indicate that Improvacuter EDTA tubes showed satisfactory performance. We conclude that the tubes are suitable for common clinical hematological use.

Evaluation of i-STAT CHEM8+ Point-of-Care Chemistry Analyzer

BACKGROUND: We evaluated the analytical performance of the Abbott i-STAT CHEM8+, a point-of-care testing system that measures 8 basic chemical analytes, namely, sodium, potassium, chloride, total carbon dioxide, BUN, creatinine, glucose, and ionized calcium. METHODS: The precision and linearity of 8 analytes were evaluated according to the CLSI guidelines EP15-A and EP6-A, respectively, using standard material provided by the manufacturer. i-STAT CHEM8+ and other primary methods (e.g. Hitachi Clinical Analyzer 7600 for 7 analytes, Nova CCX for ionized calcium) were also compared according to the CLSI guideline EP9-A2, using 113 patient samples. RESULTS: The standard deviation (SD) of within-run and total precision of 7 analytes except chloride was within the claimed SD or within the verification value. The coefficient of variation of total precision of 7 analytes except creatinine was within 2%. With regard to linearity, all 8 analytes showed first-order equation or at least no statistical difference with the first-order equation. We observed that the efficiency of i-STAT CHEM8+ was comparable to that of primary methods, and that this method has potential applications in the clinical laboratory. CONCLUSIONS: i-STAT CHEM8+ showed good precision and linearity, and an efficiency comparable to that shown by routine chemistry analyzers; thus, it has potential applications in the clinical laboratory. It can provide much faster results and relatively accurate value to clinicians in need of immediate results, such as in an emergency unit or in the intensive care unit.

Evaluation of i-STAT CHEM8+ Point-of-Care Chemistry Analyzer

BACKGROUND: We evaluated the analytical performance of the Abbott i-STAT CHEM8+, a point-of-care testing system that measures 8 basic chemical analytes, namely, sodium, potassium, chloride, total carbon dioxide, BUN, creatinine, glucose, and ionized calcium. METHODS: The precision and linearity of 8 analytes were evaluated according to the CLSI guidelines EP15-A and EP6-A, respectively, using standard material provided by the manufacturer. i-STAT CHEM8+ and other primary methods (e.g. Hitachi Clinical Analyzer 7600 for 7 analytes, Nova CCX for ionized calcium) were also compared according to the CLSI guideline EP9-A2, using 113 patient samples. RESULTS: The standard deviation (SD) of within-run and total precision of 7 analytes except chloride was within the claimed SD or within the verification value. The coefficient of variation of total precision of 7 analytes except creatinine was within 2%. With regard to linearity, all 8 analytes showed first-order equation or at least no statistical difference with the first-order equation. We observed that the efficiency of i-STAT CHEM8+ was comparable to that of primary methods, and that this method has potential applications in the clinical laboratory. CONCLUSIONS: i-STAT CHEM8+ showed good precision and linearity, and an efficiency comparable to that shown by routine chemistry analyzers; thus, it has potential applications in the clinical laboratory. It can provide much faster results and relatively accurate value to clinicians in need of immediate results, such as in an emergency unit or in the intensive care unit.