Partial Thromboplastin Time


Partial Thromboplastin Time, PTT

  • Background
  1. Evaluates Intrinsic Clotting Pathway integrity
  2. Plasma collected in a tube containing citrate, which binds Calcium and prevents initial clotting
  3. Calcium is added back to plasma, and time to clotting is measured
  • Labs
  • Normal
  1. Range: 25-41 sec
  • Causes
  • Increased