Sensitivities of Thromboplastins to Factor VII Deficiency

Plasma from a factor VII deficient patient was used to compare the sensitivities of thromboplastins from different sources. The results based on time in seconds were compared with those in abnormal control plasmas. The factor VII deficiency was detected with all thromboplastins tested; however, some showed more “sensitivity” than others. Simplastin A was the most sensitive, and the specially prepared brain thromboplastin the least sensitive, to factor VII deficiency.