Clinical and Applied Thrombosis/Hemostasis (May 2020)

From Hemophilia to Deep Venous Thrombosis Patient Samples: How to Perform an Easy Coagulometer Validation Process According to Available Guidelines

  • Silmara Aparecida de Lima Montalvão PhD,
  • Ana Paula Francisco,
  • Bittar Letícia Queiroz da Silva MSc,
  • Stephany Cares Huber PhD,
  • Helder José Aguiari,
  • Maria Carmem Gonçalves Lopes Fernandes,
  • Priscila Soares Elidio,
  • Beatriz de Moraes Martinelli,
  • Isa Macedo Tony MSc,
  • Marina Pereira Colella PhD,
  • Joyce Maria Annichinno-Bizzachi PhD

DOI
https://doi.org/10.1177/1076029620915512
Journal volume & issue
Vol. 26

Abstract

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Validation protocols for the evaluation of coagulometers are needed to help professionals select the most suitable system for their regular laboratory routines. The objective of this study was to show how high standard protocols for the coagulometer validation process can fit into the daily laboratory routine. For this study, 45 healthy individuals and 112 patient samples were analyzed. From the patient samples, 51 were investigated for deep venous thrombosis, 27 for coagulopathy, 19 for antivitamin K therapy, and 15 for hemophilia. For the assessment, the performance of the 3 coagulometers and 1 point-of-care device was considered. One of the coagulometers was a new acquisition evaluated for precision, linearity, throughput, and carryover in the first moment, and the new coagulometer was then compared with the other well-established equipment in the laboratory. In normal plasma, coefficient of variation was ≤1.8% for total precision in screening tests and ≤3.5% for within-run precision in specific assays. For prothrombin time/international normalized ratio, no significant difference was found when comparing methods. Our study showed how to compare the capacity of a reagent in order to discriminate patients with severe hemophilia from patients with moderated hemophilia, and the κ coefficient agreement was 0.669 (95% confidence interval: 0.3-1.0; P < .001). d -dimer evaluated in patients with deep venous thrombosis and controls showed a 20% discrepancy between the methods. In our experience across Latin America, the number of laboratories that has performed this process is limited. In this study, we demonstrated how to adapt the validation process for the hemostasis laboratory routine to help the professional chose the best and more suitable option.