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Prothrombin-time

Prothrombin Time Calculation

Prothrombin Time Calculator is to calculate the actual time, measured in seconds, for an anticoagulated sample of plasma or whole blood to clot after it is added to a thromboplastin reagent. Thromboplastin is a mixture of tissue factor and calcium chloride.

Related Calculators


Prothrombin Time Calculator

PT patient (seconds)
PT normal (seconds)
ISI
Result
International Normalized Ratio (INR)=

 
   
  


INR = (PT patient/PT normal)ISI

The INR is calculated from the following formula:
* PT patient = patient's measure PT (seconds)
* PT normal = laboratory's geometric mean value for normal patients (seconds)
* ISI = International Sensitivity Index