What is activating clotting time?

Activating clotting time (ACT) is a blood test that measures the time it takes for the blood to clot after activation with an activating agent. This test is commonly used in surgical procedures to monitor the effects of anticoagulant medications and heparin therapy.

In the test, a small amount of blood is drawn from the patient and mixed with an activating agent, which triggers the clotting process. The clotting time is then measured using a coagulation analyzer. Normal ACT values are between 70 and 120 seconds.

The activation agent used in the test can vary depending on the laboratory or clinic performing the test. Typically, kaolin or celite are used as activating agents.

ACT is commonly used in procedures such as cardiopulmonary bypass, hemodialysis, and interventional radiology. A prolonged ACT can indicate a higher risk of bleeding, while a short ACT can indicate a higher risk of clotting.

Overall, ACT is a useful tool for monitoring the patient's coagulation status and ensuring that anticoagulant therapy is effective and safe during surgical procedures.