Anti-Xa Assay

Coagulation

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Description

We offer a chromogenic assay for the in vitro measurement of Heparin and their analogues (indirect inhibitors of Factor Xa) and Factor Xa Direct Inhibitors, in citrated plasma. Measuring the concentration of these in patient’s plasma may be used as an aid in the management of patients in some situations. These include bleeding, recurrent thrombosis and bridging with other anticoagulants. Measurement of DOAC’s may be necessary preoperatively or after suspected overdose.

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Indications

A chromogenic Anti-Xa assay is used to quantitate levels of the following drugs:

• Direct Inhibitors of Xa (DOAC’s)
• Apixaban
• Rivaroxaban
• Edoxaban
• Indirect Inhibitors
• Unfractionated/Low Molecular Weight Heparin
• Orgaran
• Fondaparinux

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Sample Type

Plasma (Citrate 2.7ml Blue top) x 1

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Reference Range

Not applicable.

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Turnaround Time

Within 2 weeks (or on demand)

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Testing Frequency

As required (available outside core hours).

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External Notes

The accuracy of all coagulation tests is greatly influenced by pre analytical variables. It is essential that sample quality is given the highest of priorities. Samples which fail to meet quality criteria including age of sample, specimen fill (>90%), haemolysed, clotted or activated samples will be rejected and a repeat sample requested.

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Patient Preparation

No specific requirements.

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References

Kitchen et al. Measurement of non-coumarin anticoagulants and their effects on tests of Haemostasis: Guidance from the British Committee for Standards in Haematology. British Journal of Haematology, 2014, 166, 830-841

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Please note: the above information is subject to change and we endeavour to keep this website up to date wherever necessary.