PROTIME-INR

Test Code

LAB320

Alias/See Also

Prothrombin Time; Protime; Pro-time, PT

CPT Codes
85610

Includes

Prothrombin time in seconds; international normalized ratio (INR)

Instructions

"Routine venipuncture;
do not use syringe for collectionBlue top (sodium citrate) tube2.7 mL; 90% of tube must be filled."

Transport Temperature

Room temperature

Specimen Stability

Room temperature, stable 12 hours.

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

"Tube <90% full; visible hemolysis; clotted specimen; improperly labeled specimen
blood collected with anticoagulants such as EDTA, heparin, oxalate, or citrate"

Methodology
Turbidimetric clot detection (optical density)

Setup Schedule

Daily

Report Available

Urgent: 4 hours; inpatient STAT: 1 hour; outpatient STAT: 2 hours

Reference Range

"Prothromibin Time (PT): 11.6-14.3 sec
INR: 0.83 - 1.21 ; Critical Level: Less than 0.19 or Greater than 5.01
Therapeutic ranges: INR: 2.0-3.0: prophylaxis for venous thromboembolism, and treatment for deep vein thrombosis and pulmonary embolism.INR: 2.5-3.5: mechanical heart valves, recurrent embolism."

Clinical Significance

"The prothrombin time is a measure of the extrinsic coagulation pathwayinvolving factors II, V, VII, X, and fibrinogen. It is used to monitororal anticoagulant therapy. The INR is used for comparison of protimeresults for patients that are on chronic stable oral anticoagulanttherapy (i.e. Coumadin or warfarin).
Click here to see COAGULATION TESTING ALGORITHM
Click here to see FROZEN PLASMA DOSING ALGORITHM"

Additional Information
Guidelines For HyperCoagulable Testing
Frozen Plasma Dosing Algorithm to Correct INR
NCD Prothrombin Time (PT)

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.