ARUP's Laboratory Test Directory

Prothrombin Time/International Normalized Ratio : 0030224

Mnemonic: PT INR

Methodology: Electromagnetic Mechanical Clot Detection
Performed: Sun-Sat
Reported: 1-2 days
Specimen Required: Collect: Lt. blue (sodium citrate)

Specimen Preparation: Transfer 1 mL platelet-poor plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)

Storage/Transport Temperature: Frozen.

Unacceptable Conditions: Serum. Refrigerated, clotted, or hemolyzed specimens.

Stability (collection to initiation of testing): Ambient: 24 hours; Refrigerated: Unacceptable; Frozen: 2 weeks
Reference Interval:



       
 
Test Number Components Reference Interval
 International Normalized Ratio Coumadin Therapy:
  INR: 2.0-3.0 conventional anticoagulation
  INR: 2.5-3.5 intensive anticoagulation
 Prothrombin Time 12.0-15.5 seconds

Note: Reference intervals established using 3.2 percent sodium citrate.
CPT Code(s): 85610
Cross References: INR (Prothrombin Time/International Normalized Ratio), Protime, PT/INR (Prothrombin Time/International Normalized Ratio), PT/International Normalized Ratio (Prothrombin Time/International Normalized Ratio)