title: Validation of a point-of-care prothrombin time test after cardiopulmonary bypass in cardiac surgery.
abstract: Point-of-care coagulation monitoring can be used for the guidance of haemostasis management. However, the influence of time on point-of-care prothrombin time testing following protamine administration after cardiopulmonary bypass has not been investigated. Bland-Altman and error grid analysis were used to analyse the level of agreement between prothrombin time measurements from point-of-care and laboratory tests before cardiopulmonary bypass, and then 3 min, 6 min and 10 min after protamine administration. Prothrombin times were expressed as International Normalised Ratios. While the point-of-care and laboratory prothrombin time measurements showed a high level of agreement before bypass, this agreement deteriorated following protamine administration to a mean (SD) bias of -0.22 (0.13) [limits of agreement 0.48-0.04]. Error grid analysis revealed that 35 (70%) of the paired values showed a clinically relevant discrepancy in international normalised ratio. At 3 min, 6 min and 10 min after cardiopulmonary bypass there is a clinical unacceptable discrepancy between the point-of-care and laboratory measurement of prothrombin time.
authors: Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, the Netherlands.
authors: M I
authors: MI
authors: Meesters
authors: Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, the Netherlands.
authors: G
authors: G
authors: Kuiper
authors: Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, the Netherlands.
authors: A B A
authors: AB
authors: Vonk
authors: Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, the Netherlands.
authors: S A
authors: SA
authors: Loer
authors: Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, the Netherlands. c.boer@vumc.nl.
authors: C
authors: C
authors: Boer
mesh_terms: D000368:Aged; D001777:Blood Coagulation / Q000187:drug effects; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D005260:Female; D006494:Heparin Antagonists / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D019095:Point-of-Care Systems / Q000592:standards / Q000706:statistics & numerical data; D000067716:Point-of-Care Testing / Q000592:standards* / Q000706:statistics & numerical data; D011446:Prospective Studies; D011479:Protamines / Q000627:therapeutic use*; D011517:Prothrombin Time / Q000379:methods* / Q000706:statistics & numerical data; D015203:Reproducibility of Results
chemical_list: D006494:Heparin Antagonists; D011479:Protamines
keywords: cardiac surgery; heparin; point-of-care testing; protamine; prothrombin time