Delayed double reading of whole blood clotting test (WBCT) results at 20 and 30 minutes enhances diagnosis and treatment of viper evenomation

The whole blood clotting test (WBCT) is a simple test of coagulation that is often used in the assessment, diagnosis, and therapeutic monitoring of snakebite patients in sub-Saharan Africa. WBCT requires only a clean glass tube and several milliliters of venous blood and is ideal for use in poorly equipped health centers throughout the rural areas where 95% of snakebites occur. However, questions surrounding the accuracy and reliability of the test remain unanswered due to variations in testing conditions and a lack of comparative research with which to validate them. This is the first study to evaluate WBCT results at both 20-min (WBCT20) and 30-min (WBCT30) reading times in the same group of snakebite patients. Methods In order to define the best reading time, the authors compared the results of serial WBCT evaluation at both 20 and 30 min after collection in 23 patients treated for snake envenomation in Bembèrèkè, northern Benin. Results WBCT results were identical at both reading times in patients without coagulopathy or when coagulation was restored permanently following a single dose of antivenom. Out of 17 patients with coagulopathy, 14 showed discrepancies between WBCT20 and WBCT30 results in at least one pair of serial evaluations. These could be completely contradictory results (e.g. normal clot at WBCT20 and no clot at WBCT30) or a marked difference in the quality of the clot (e.g. no clotting activity at WBCT20 and an unstable partial clot at WBCT30)...

Pruebas del coagulograma y componentes de la hemostasia. Utilidad para diagnosticar las diátesis hemorrágicas / Tests of coagulation and hemostasis components. Usefulness for diagnosing hemorrhagic diathesis

El coagulograma comprende un conjunto de pruebas que exploran la participación de todos los componentes de la hemostasia: endotelio vascular, actividad plaquetaria, factores plasmáticos y fibrinolíticos. Con frecuencia, la ejecución de estas pruebas resulta compleja para el personal técnico, por lo que la profundización en el conocimiento e interpretación de los resultados de cada una de estas, debe redundar en el fortalecimiento y preparación de los profesionales de la salud. En el presente trabajo se describen las principales pruebas del coagulograma convencional, el principio y los valores de referencia de cada una, así como las posibles enfermedades de acuerdo con la alteración del sistema hemostático que corresponde a la alteración del coagulograma, con el objetivo de brindarle al médico una información básica para la correcta ejecución y adecuada interpretación de los resultados

Coagulogram comprises a set of tests, which explore the participation of all components of hemostasia: vascular endothelium, platelet activity, plasma and fibrinolytic factors. Often, the technical staff finds complex to do these tests, so deepening knowledge, understanding, and interpreting the results of each of these tests should result in strengthening and training of health professionals. This paper describes the main conventional coagulation tests, the beginning and the reference values of each of them, and the possible diseases according to the alteration of the hemostatic system corresponding to the alteration of coagulation, with the aim of providing medical background information for the proper performance and proper interpretation of results