CHROMOGENIC FACTOR XA ASSAY
(HEPARIN ASSAY,FACTOR Xa ASSAY, LOW MOLECULAR WEIGHT HEPARIN ASSAY, ANTI-XA)
Specimen Collection Requirements
Two light blue (3.2% Buffered Sodium Citrate) top tubes
Ambient (15-25°C) 2 hours from the time of collection, Freeze if transport is > 2 hours
Samples not processed and/or transported as required, clotted samples, samples collected in containers other than 3.2% Buffered Sodium Citrate, tubes filled less than 90%, samples from patients with a Hematocrit greater than 55%, hemolyzed samples due to ex-vivo causes (i.e., difficult draw, poor sample draw), whole blood samples that were frozen before processing
WHOLE BLOOD Ambient: 1 hour PLASMA Ambient: 2 hours from time of collection; Frozen: -20°C 1 month, -70°C 6 months
The type of heparin, unfractionated or specified brand of low molecular weight heparin (i.e., Enoxaparin, Lovenox), the patient is receiving must be noted. The specific type must be provided to perform the testing. If low molecular weight heparin is being used, the brand name, last dose and mode of infusion must be on all orders.
Samaritan Health Services Laboratories
Preliminary Therapeutic Guidelines for LMW Heparin Levels:
Twice-a-Day Subcutaneous: 0.5-1.1 Units/mL
Once-a-Day Subcutaneous: 1.0-2.0 Units/mL
Optimum sampling time is 4hrs post-injection.
Methodology: Anti-Xa Chromogenic assay on the Stago
Thursday, January 5, 2017 03:42:03 AM