Factor VIII Activity

Message

Performed in the Hematology Laboratory x5475, 76. Sample MUST be drawn to minimum fill line on tube.

Test Code

Alias/See Also

Factor VIII

CPT Codes
85240

Preferred Specimen

Plasma

Minimum Volume

2.7 mL. Sample MUST be drawn to minimum fill line on tube or the sample will be rejected as QNS.

Instructions

If drawn with other coagulation assays: for up to 3 tests draw 2, 2.7mL sodium citrate tubes. For 4 or more tests, draw 3, 2.7 mL sodium citrate tubes.

Transport Container

Light Blue Top (Sodium Citrate), 2.7 mL draw tubes

Transport Temperature

Room temperature

Specimen Stability

Refrigerator Stability: 4 hours
Plasma is stable for 6 months frozen at -70 degrees C.

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Gross hemolysis, QNS, Clotted

Methodology

Optical clot detection

Setup Schedule

Monday-Friday from 8-4pm. Can be performed on weekends and holidays from 7-3 pm with Hematology Pathologist approval only.
Special arrangements for STAT/after hours testing can be made by calling the Hematology laboratory at x5475.

Reference Range

0 -	5 days	50%	154%
		50%	154%
5 days -	1 month	50%	157%
		50%	157%
1 month -	3 months	50%	125%
		50%	125%
3 months -	6 months	50%	109%
		50%	109%
6 months -	150 years	50%	150%
		50%	150%
**Female Ranges are in BLUE

Clinical Significance

To work up abnormal PTT; congenital or acquired deficiencies; to monitor hemophilia or vWD treatment

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.