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POCT Prothrombin Time, Fingerstick

Item Value
Approval req'd? No
Available Stat? Yes
Test code
Test group Prothrombin time
Performed by Authorized Point of Care testing site staff
In House Availability During clinic hours
Method Thromboplastic activation, magnetic bead endpoint detection (Coaguchek S¨)
Collection Instructions Venipuncture samples may be collected using only plastic syringes. Glass tubes or syringes may not be used.

See Coagucheck procedure for proper fingerstick sample collection technique
Container type
Amount to Collect One drop
Sample type Capillary (fingerstick) blood (venous whole blood acceptable)
Preferred volume One drop
Min. Volume 10 µL
Units INR
Normal range
Normal (untreated) 0.9-1.2
Critical value An INR > 5.0 must be confirmed with a Prothrombin Time performed in the Clinical Laboratory
Synonyms PT; coumadin; warfarin
Additional information The CoaguChek should not be used with patients having the following conditions:
a. Lupus anticoagulant
b. Triglyceride > 500
c. Bilirubin > 20
d. On heparin therapy within the last 24 hours.
e. Hematocrit < 30 or > 52.

Collect only the first drop of blood from a fingerstick. The second drop of blood may have begun the clotting process.

Plasma and serum are not acceptable for testing.

The minimum volume is 10 uL. Low sample volume will cause ERROR display.

Do not attempt to add more blood to the test strip after testing has begun. Repeat test with a new fingerstick and equipment.

If the patient is on intravenous infusion therapy, do not collect the sample from the same arm.

The CoaguChek S monitor, test strips, and Code Chip operate on magnetic principles. It is important to keep these items away from magnetic materials and magnetic fields. Magnetic fields will erase the calibration information on the Code Chip
Last Updated 11/17/2011 4:03:05 PM
Entry Number 1120
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