Vitamin K Dependent Clotting Factors Half Life

Patients with vitamin k deficiency produce decarboxylated forms of the vitamin k dependent factors pivkas proteins induced in vitamin k absence.

Vitamin k dependent clotting factors half life. The aim of this research is to develop a joint model for the vk dependent clotting factors ii vii ix and x and the anticoagulation proteins proteins c and s during warfarin initiation. 127 129 these rare autosomal recessive disorders have an estimated incidence of 1. When vitamin k catalyzed γ carboxylation becomes suppressed these. I received a question recently about coumadin warfarin therapy and coagulation factor half lives.

Vitamin k is an essential cofactor in the activation of certain proteins within your body 1. 4 6 hrs for example falls precipitously initially during the first few days of warfarin therapy and the pt reflects mainly a reduction of factor vii initially. The 4 vit k dependent clotting factors ii vii x. A theoretical model describing the relationship between the half life times of vitamin k dependent coagulation factors and the control frequency of oral anti coagulation therapy is presented.

Rates of decline for each factor is inversely proportional to its half life. The vitamin k dependent coagulation factors are factors ii vii ix x proteins c and s. A theoretical model describing the relationship between the half life times of vitamin k dependent coagulation factors and the control frequency of oral anticoagulation therapy is presented. A short review about the place of coagulation factor vii in the initial phase of blood coagulation is given.

Warfarin acts by inhibiting the reduction of vitamin k vk to its active form thereby decreasing the production of vk dependent coagulation proteins. Vitamin k1 injection phytonadione injectable emulsion usp aqueous dispersion of vitamin k1 for parenteral injection possesses the same type and degree of activity as does naturally occurring vitamin k which is necessary for the production via the liver of active prothrombin factor ii proconvertin factor vii plasma thromboplastin component factor ix and stuart factor factor x. Table iii half life of vitamin k dependent clotting factors factor ii factor vii factor ix factor x t 1 2 elimination h 60 4 2 17 31 duration of action of exogenously administered factors equal to that of endogenously produced factors. Pivka ii has a half life of up to 70 hours shapiro et al 1986 and thus can be measured even after vitamin k therapy and normalization of the pt.

Without the activation step certain biochemical reactions cannot be completed. Combined deficiency of the vitamin k dependent factors may result from missense mutations in the genes for vitamin k reductase vkorc 1 or gamma glutamyl carboxylase.