Laboratory Medicine

Test Directory / International Normalised Ratio (INR)

International Normalised Ratio (INR)

Citrated Plasma

Test	International Normalised Ratio (INR)
Common Abbreviations	INR
Profile
Clinical Indication	Calculation derived from the Prothrombin Time (PT/MNPT^ISI). Used to monitor Warfain.
Specimen Type	Blood
Sample Type	Citrated Plasma
Minimum Volume	1 x 3mL (adult) 1 x 1mL (paed) (citrated plasma must be filled to bottle line)
Special Precautions	Only use for Warfarin monitoring.
Stability	24 hrs at room temp
Turnaround Time	1 hour (urgent) 4 hours (routine)
Laboratory	York & Scarborough Hospital
Reference Interval	N/A
Limitations	Haemolysis, gross lipaemia, high haematocrit may interfere with measurement. Over or under filled samples cannot be used due to ratio between blood and citrate
Additional Information

Update for visitors

Visiting restrictions are in place at our hospitals to stop the spread of norovirus. These restrictions will be in place until further notice.

The following wards are closed to visitors:

York Hospital: Ward 29 and Ward 37.

There are four exceptions only to the restrictions. These are:

For patients who are receiving end of life care

Paediatric patients (babies and children)

Maternity care

The family carers of those with dementia

We understand these restrictions can be difficult when a loved one is unwell. The restrictions will be reviewed daily and lifted as soon as it is safe. Thank you for your understanding as we try to reduce the spread of norovirus in our hospitals.