Whole blood clotting test explained

Whole blood clotting test
Purpose:	to check coagulation mechanism in the blood following a snake bite

The whole blood clotting test is a blood test used to check the coagulation mechanism in the blood following a snake bite.^[1] If the test is positive after a bite in South East Asia it indicates the snake was a viper rather than an elapid.^[1] It can also be used to assess the effectiveness of antivenin therapy.^[2]

Method

This test indirectly measures the severity of defibrinogenation in envenomed samples.^[3] The test is done by collecting 2 ml of venous blood in a dry and clean glass tube. The clot and stability of the formed clot is checked after 20 minutes.^[4]

Notes and References

1. Book: Guidelines for the management of snake-bites . 2010 . WHO . 73 . https://web.archive.org/web/20140209033057/http://apps.searo.who.int/PDS_DOCS/B4508.pdf. dead. February 9, 2014. ((978-92-9022-377-4)).
2. Chippaux. J. P.. Williams. V.. White. J.. 1991. Snake venom variability: methods of study, results and interpretation. Toxicon. 29. 11. 1279–1303. 10.1016/0041-0101(91)90116-9. 0041-0101. 1814005.
3. Sano-Martins. I. S.. Fan. H. W.. Castro. S. C.. Tomy. S. C.. Franca. F. O.. Jorge. M. T.. Kamiguti. A. S.. Warrell. D. A.. Theakston. R. D.. September 1994. Reliability of the simple 20 minute whole blood clotting test (WBCT20) as an indicator of low plasma fibrinogen concentration in patients envenomed by Bothrops snakes. Butantan Institute Antivenom Study Group. Toxicon. 32. 9. 1045–1050. 10.1016/0041-0101(94)90388-3. 0041-0101. 7801340.
4. Benjamin. Jordan Max. Chippaux. Jean-Philippe. Sambo. Bio Tamou. Massougbodji. Achille. 2018-05-16. Delayed double reading of whole blood clotting test (WBCT) results at 20 and 30 minutes enhances diagnosis and treatment of viper envenomation. The Journal of Venomous Animals and Toxins Including Tropical Diseases. 24. 14. 10.1186/s40409-018-0151-1. 1678-9199. 5956810. 29796013 . free .