Activated
Partial Thromboplastin Time (aPTT) - 2
Normal range:
25 – 38 seconds
Clinical application:
Used to monitor heparin therapy
Therapeutic range:
2 – 2.5 times normal control (50 –
95 seconds)
Used to screen for coagulopathies
such as deficiencies of:
XII
X
V
II
I
Intrinsic pathway
Common pathway
XI
IX
VIII
