Activated clotting time

The activated (blood) coagulation time ( English Activated clotting time, ACT ) is a measure of blood clotting , and indicates the time after which whole blood by the addition of kaolin begins to clot (generation of coagulation ).

The ACT is used in particular for rapid blood coagulation testing ( POCT ) close to the patient , in order to monitor the necessary anticoagulation with heparin when using a dialysis or heart-lung machine . The advantage over other coagulation tests such as aPTT is that the patient's blood does not have to be centrifuged before the test, but with ACT whole blood is immediately introduced into the measuring device. Measured values are available within a few minutes. Another advantage of the ACT is that it still enables the blood coagulation inhibition to be measured even with strong heparinization, whereby the aPTT would be extended into the no longer measurable range.

The normal value for the ACT depends on the manufacturer and is around 80–100 seconds and should, for example, be around 400–600 seconds when connected to the heart-lung machine.

Individual evidence

↑ Reinhard Larsen: Anesthesia and intensive medicine in cardiac, thoracic and vascular surgery . Springer, Berlin et al. (1st edition 1986) 2012, ISBN 978-3-642-21020-4 .

[Larsen_2012_p.-1] Reinhard Larsen: Anesthesia and intensive medicine in cardiac, thoracic and vascular surgery . Springer, Berlin et al. (1st edition 1986) 2012, ISBN 978-3-642-21020-4 .