Oyl
0
Prothrombin Time (PT)
$15.90
A blood coagulation test that measures clotting time through the extrinsic pathway, commonly used to monitor warfarin therapy and evaluate clotting factor deficiencies.
 
SKU
005199
CPT
85610
Methodology
Prothrombin time reagent containing thromboplastin and calcium chloride is mixed with the patient plasma and the time to clot formation is measured photo-optically. The calcium chloride overcomes the citrate anticoagulant and allows the tissue factor in the thromboplastin to initiate coagulation. The prolongation of the clotting time correlates with the degree of deficiency or inhibition of the extrinsic pathway factors.
Turnaround Time
Within 1 day
Prothrombin Time (PT) is a blood coagulation test that measures how long it takes for blood to clot through the extrinsic pathway. This test evaluates the function of coagulation factors II, V, VII, X, and fibrinogen, which are essential for normal blood clotting. PT results are reported in seconds and also converted to International Normalized Ratio (INR) values for standardization across different laboratories. Prolonged PT can indicate deficiencies in vitamin K-dependent clotting factors, liver disease, disseminated intravascular coagulation (DIC), or the presence of clotting inhibitors. This test is most commonly used to monitor warfarin (Coumadin) anticoagulant therapy, where the goal is typically an INR between 2.0-3.0 for most conditions. PT testing is essential for patients on blood thinners to ensure they receive adequate protection against blood clots while minimizing the risk of bleeding complications.
Markers Included
International normalized ratio (INR); prothrombin time
Reference Range

See table.

Age

Range

Prothrombin Time (PT)

0 to 30 d

9.8−13.2 sec

1 to 6 m

9.8−12.6 sec

7 m to 1 y

9.8−12.2 sec

2 to 17 y

9.9–12.1 sec

≥18 y

9.1−12.0 sec

International Normalized Ratio (INR)

0 to 1 m

0.9−1.4

>1 m

0.9−1.2

Order Code
005199
Order Code Name
Prothrombin Time (PT)
Order Loinc
34528-0
Result Code
115107
Result Code Name
INR
Uofm
Result Loinc
6301-6
Order Code
005199
Order Code Name
Prothrombin Time (PT)
Order Loinc
34528-0
Result Code
015289
Result Code Name
Prothrombin Time
Uofm
sec
Result Loinc
5902-2
Order Code
Reflex 1
Order Code Name
115109
Order Loinc
INR (Thromborel-S)
Result Code
115109
Result Code Name
INR (Thromborel-S)
Uofm
Result Loinc
6301-6
Order Code
Reflex 1
Order Code Name
015290
Order Loinc
PT (Thromborel-S)
Result Code
015290
Result Code Name
PT (Thromborel-S)
Uofm
sec
Result Loinc
5902-2