Assay

Low Molecular Weight Heparin (anti Xa)

Key Words

Low Molecular Weight Heparin, LMWH, anti Xa

Specimen Collection

3.0ml Citrate (Green lid). 1.4ml Citrate for paediatric (Green lid). Fill to mark.

Turnaround time

First working day post-collection

Test indications

Pregnancy, renal impairment and history of bleeding/thrombosis while on Low Molecular Weight Heparins

Interferences

Lipaemia, haemolysis, anticoagulants

Reference Range

Adult reference ranges please refer to the table below, referenced from BSH Guidelines*: 

Paediatric reference ranges, referenced from BSH guidelines*:

"In neonates and children receiving LMWH, we suggest monitoring peack LMWH anti-FXa, aiming for 0.5-1.0iu/mL, in a sample taken 4 hours after subcutaneous injection once steady state has been achieved after administration of at least three doses"

*Measurement of heparin, direct oral anti-coagulants and other non-coumarin anti-coagulants and their effects on haemostasis assays: A British Society for Haematology Guideline - Br J Haematology 2024.205:1302-1318 

Minimum retesting interval

N/A