haematology users' handbook - University College London Hospitals

Test Specimen type Key Factors
affecting
tests
Notes
Reference
Range
Out of hours
service
Time Limit for
requesting
additional
tests from
time of
venesection
Turnaround
time from
receipt of
sample
Factor Assays
FVIII, FIX, FXI, FXII
FII, FV, FVII, FX
FXIII
Lupus Anticoagulant
test
Dilute Russell’s Viper
Venom Time test
or Taipan Venom
Time test (on
warfarin).
4.5ml Sodium
Citrated samples –
contact the
laboratory for the
number of samples
required (dependent
on tests requested).
3 x 4.5ml Sodium
Citrated samples
Heparin and
Warfarin.
Acute illness
(contact the
laboratory).
Delayed
receipt of
sample
Warfarin,
Heparin and
Rivaroxaban
therapy.
Delayed
receipt of
sample
Required factor assays
must be specified on the
request form.
Lupus Anticoagulant testing
is inappropriate when
patients are receiving
heparin therapy.
An SST sample is required
if Cardiolipin Antibody
testing is also requested.
Contact the
laboratory
Factor VIII
and Factor IX
only: by
agreement
with the
Haematology
Consultant
on call and
subject to
staff
availability.
No out of
hours service
Contact the
Laboratory
Contact the
laboratory
3 working
days
3 working
days
Heparin induced
thrombocytopaenia
(HIT) screen
Heparin:PF4
antibody assay
1 x 4.5ml Sodium
Citrated sample
(preferred)
Urgent test:
send the
sample to the
lab.
Immediately.
This test MUST be
authorised by a
Haematology Consultant
(i.e. not a SpR): contact via
the Haematology SpR
(bleep 7044/7000) or
switchboard out of hours.
Contact the
laboratory
By agreement
with the
Haematology
Consultant
on call and
subject to
staff
availability.
Contact the
Laboratory
Urgent:
1 working
day
Non-urgent:
5 working
days
HAEM-PD-UserHbook V8 Haematology and Blood Transfusion User Handbook Page 24 of 38
Authors: Karen Orfinada (Senior Biomedical Scientist)
Sally McDonald (Senior Biomedical Scientist) Authorised by: Dave Barnett Review Date: August 2015