Factor Assays

Pathology category

Haematology

Code

See above

Referral code

Request form

Standard

Test information

Note that paediatric samples (<16 y/o) will be referred to Special Coagulation Department, Birmingham Children’s Hospital, Steelehouse Lane, Birmingham, B4 6NH Telephone: 0121 333 9999

Guidelines

Pre-analytical

Discuss urgency of request with laboratory.

A full specimen container per factor is required for accurate testing.

Lipaemic or jaundiced samples may cause problems with testing.

Haemolysed, underfilled or clotted samples will be rejected

Sample transport should be at 4-25C and reach the laboratory ASAP Please note: the samples must arrive within 4 hours of collection otherwise they will be rejected by the laboratory

Reference range

Tube type

Tube type info

2.7ml Blue top citrate (1 per factor)

1.8 ml paediatric citrate (1 per factor)

Special requirements

Usually in discussion with lab.

Minimum volume

1 tube per factor minimum 90% full (to the thick black line on the bottle)  – essential to ensure 1:9 ratio of anticoagulant:blood

Assay frequency

As required – non routine

Urgent Factor VIII & Factor IX available out of hours. Please discuss with laboratory

TAT Inpatient (urgent)

Discuss with lab

TAT Inpatient

Discuss with lab

TAT GP/Outpatient

Discuss with lab

Referral lab

local