Assumptions:
(1) The decline in coagulant activity follows first order kinetics.
(2) The factors are primarily intravascular (so distribution volume is the plasma volume).
Parameters:
(1) minimum Factor VIII coagulant activity required (trough below next infusion) in IU/mL, as listed in previous section
(2) baseline Factor VIII coagulant activity prior to any therapy
(3) half-life of Factor VIII activity in hours
amount of Factor VIII activity that much be supplied at trough levels =
= (minimum activity required) - (baseline level) =
= (peak concentration) * EXP((-1) * k * (time in hours since last infusion))
k =
= 0.693 / (half-life in hours)
peak concentration in IU/mL =
= ((minimum activity required) - (baseline level)) / EXP((-1) * 0.693 * (time since infusion) / (half-life in hours))
dose of Factor VIII coagulant activity to provide in IU =
= (peak concentration in IU/mL) * (plasma volume in mL)
