We have located links that may give you full text access.
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Heparin neutralization is essential for accurate measurement of factor VIII activity and inhibitor assays in blood samples drawn from implanted venous access devices.
The purpose of this study was to determine the prevalence and effect of heparin contamination in samples drawn from implanted venous access devices (VADs, ports) on factor VIII activity and Bethesda inhibitor assay (BU) and the efficacy of heparinase to neutralize heparin. Plasma samples containing 85, 45, and 2 U/dL factor VIII were spiked in vitro with heparin from 0 to 3 U/mL. Factor VIII activity was assayed with a one-stage clotting assay on paired samples before and after heparinase, 25 mg/mL plasma. Paired patient samples drawn from VADs were assayed for heparin concentration, factor VIII, and BU before and after heparinase. At all three concentrations of factor VIII in vitro, the addition of heparin at 0.12 to 0.25 U/mL decreased assayed factor VIII activity. Heparinase neutralized up to 2 U/mL heparin and resulted in accurate factor VIII determination. Of 105 VAD samples, 47 (45%) had heparin contamination >0.05 U/mL. Of 47 heparin-contaminated samples, 42 showed decreased factor VIII activity in before/after comparisons. False-positive BU results were detected in 6 of 47 heparin-contaminated samples. Heparin contamination occurs frequently in samples drawn from VADs and could increase costs through excessive factor concentrate use. We recommend that all VAD samples be pretreated with heparinase before the assay of factor VIII activity or Bethesda inhibitor titers.
Full text links
Related Resources
Trending Papers
The 'Ten Commandments' for the 2023 European Society of Cardiology guidelines for the management of endocarditis.European Heart Journal 2024 April 18
Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies.Journal of Personalized Medicine 2024 Februrary 4
A Guide to the Use of Vasopressors and Inotropes for Patients in Shock.Journal of Intensive Care Medicine 2024 April 14
Prevention and treatment of ischaemic and haemorrhagic stroke in people with diabetes mellitus: a focus on glucose control and comorbidities.Diabetologia 2024 April 17
Diagnosis and Management of Cardiac Sarcoidosis: A Scientific Statement From the American Heart Association.Circulation 2024 April 19
Eosinophilic Esophagitis: Clinical Pearls for Primary Care Providers and Gastroenterologists.Mayo Clinic Proceedings 2024 April
Essential thrombocythaemia: A contemporary approach with new drugs on the horizon.British Journal of Haematology 2024 April 9
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app