ACT
Pronunciation: A-C-T
Also written as: ACT — activated clotting time
A bedside test measuring the time for blood to clot, used to monitor anticoagulation during cardiac surgery.
Full Definition
Activated clotting time (ACT) is a point-of-care coagulation test that measures the time required for whole blood to clot in the presence of a contact activator such as kaolin or celite. In cardiothoracic anesthesia and cardiac surgery, ACT monitoring is essential for managing anticoagulation during cardiopulmonary bypass. Normal ACT values range from 80-120 seconds, while therapeutic anticoagulation for bypass requires ACT values greater than 480 seconds. The test provides rapid results allowing for real-time adjustment of heparin dosing and monitoring of protamine reversal.
Usage
Usage note: Always capitalize as acronym; specify target values when documenting.
In Context
- "The ACT was 520 seconds, confirming adequate anticoagulation for bypass initiation." — perfusion record
- "Serial ACT measurements guided heparin dosing throughout the procedure." — anesthetic record