Table 1. Formulas for factor consumption... | American Society of Hematology

Table 1.

Formulas for factor consumption based on inhibitor titer, patient weight, and severity of bleeding episode

Inhibitor titer (BU)	Severity of bleeding episode	Factor (type and dosage)
BU = O:	Minor	40 U/kg FVIII
	Moderate	80 U/kg FVIII
	Major	100 U/kg/d × 7d FVIII in hospital
BU = 5:	Minor	40 U/kg FVIII + 50 U/kg FVIII^*
	Moderate	80 U/kg FVIII + 50 U/kg FVIII^*
	Major	100 U/kg/d × 7d FVIII + 50 U/kg FVIII^*
BU = 25:	Minor	aPCC: 180 U/kg^†
		pFVIII^†: 1/4[30 U/kg bid × 2 d + 25^0.25^30 U/kg × 1 dose^‡]
	Moderate	aPCC: 360 U/kg^†
		pFVIII^†: 1/4[30 U/kg/bid × 4 d + 25^0.25^30 U/kg × 1 dose^‡]
	Major	pFVIII: 50,000 U/episode

Inhibitor titer (BU)	Severity of bleeding episode	Factor (type and dosage)
BU = O:	Minor	40 U/kg FVIII
	Moderate	80 U/kg FVIII
	Major	100 U/kg/d × 7d FVIII in hospital
BU = 5:	Minor	40 U/kg FVIII + 50 U/kg FVIII^*
	Moderate	80 U/kg FVIII + 50 U/kg FVIII^*
	Major	100 U/kg/d × 7d FVIII + 50 U/kg FVIII^*
BU = 25:	Minor	aPCC: 180 U/kg^†
		pFVIII^†: 1/4[30 U/kg bid × 2 d + 25^0.25^30 U/kg × 1 dose^‡]
	Moderate	aPCC: 360 U/kg^†
		pFVIII^†: 1/4[30 U/kg/bid × 4 d + 25^0.25^30 U/kg × 1 dose^‡]
	Major	pFVIII: 50,000 U/episode

One-time dose of FVIII to “neutralize” the inhibitor.

The “1/4” represents the 25% failure rate of aPCC and thus the use of pFVIII.

The initial dose for pFVIII was calculated by assuming an antiporcine titer approximately 25% as high as that of the antihuman titer.