Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
This is the time it takes anticoagulated plasma to clot after being exposed to tissue factor and calcium. It is used as part of a clotting screen and is senstive to deficiencies in Factors VII, X, V, II and Fibrinogen. It is also the basis of the INR which is used to monitor and control Vitamin K antagonist anticoagulant therapy.
Specimen container paediatric:
Light blue – sodium citrate
Specimen container adult:
Light blue – sodium citrate
Minimum volume paediatric:
1.3mL
Minimum volume adult:
2.7mL
Special requirements:
Tube must be correctly filled to line, to ensure correct ratio of blood to anticoagulant, ensure adequate mixing.
Sample stability:
24 hrs
Transport requirements:
Samples should be transported to lab without delay
Freq analysis:
Continuous
Add on test:
[email protected] (external)
Quality assurance:
UK NEQAS Blood Coagulation
Reference ranges:
Prothrombin Time 10 to 13 seconds.
Note: For Haemostatic tests, paediatric reference ranges may be different to adult ranges.
Other info:
As part of a coagulation screen.