Chromogenic Factor VIII Assay
Label Mnemonic: | CH8 |
Epic code: | LAB8465 |
Downtime form: | Doctor/Provider Orders - Pathology Core and Specialty Care Nursery |
Hemostasis/Thrombosis
6240 RCP
356-3573
6240 RCP
356-3573
Specimen(s):
Plasma
Collection Medium:
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Light Blue top tube 2.7 mL (Na Citrate) |
Minimum:
Full draw; 2.7 mL light blue top
Rejection Criteria: Short drawn tube, clot, traumatic tap (excessive hemolysis).
Delivery Instructions:

Turn Around
Time:
24–48 hours
Reference Range:
43–159%
Methodology:
Chromogenic
CPT Code:
85130
See Additional Information:
Impact of Common Anticoagulants on Coagulation Tests
Impact of Common Anticoagulants on Coagulation Tests
The chromogenic factor VIII activity assay utilizes bovine factor X and human thrombin and factor IXa. It is insensitive to emicizumab, but may yield unreliable results in the presence of direct oral anticoagulants (dabigatran, rivaroxaban, apixaban), high concentrations of heparin (>2 IU/mL), strong lupus anticoagulants (ratio >1.8), or the Mim8 bispecific antibody.