Activated clotting time as a screening test prior to catheter‐based cardiovascular procedures

Abstract

The activated clotting time (ACT) was investigated as a rapid, inexpensive, point-of-service screening test for coagulation abnormalities prior to catheter-based procedures. A total of 963 patients were screened by obtaining a history, standard coagulation profile, and activated coagulation time. The prevalence of normal patients (normal ACT and coagulation profile) was 94% (sensitivity = 91%; specificity = 27%). A normal ACT had a positive predictive value of 95%. The ACT was an acceptable screening test due to its ability to predict positively a low rate of bleeding complication and normal coagulation studies. Patients with ACT > 150 sec should be further evaluated with a screening coagulation panel. Additionally, given its low specificity, coagulation studies should be obtained in high-risk patients since an abnormal ACT does not effectively correlate with abnormal coagulation studies.

Management of regional citrate anticoagulation in pediatric high-flux dialysis: activated coagulation time versus post-filter ionized calcium

“…The ACT is currently a standard procedure for monitoring anticoagulation in extracorporeal circuits, such as in clinical settings of cardiopulmonary bypass, hemodialysis, and apheresis treatment, and during surgical and interventional procedures requiring anticoagulative treatment, including cardiac and vascular surgery [15][16][17]. The ACT has also been advocated as a routine preoperative screening test for detecting coagulation disorders [18,19]. As a whole blood coagulation test, the ACT is affected by different anticoagulants and therefore can be used for monitoring the effects of unfractionated heparin, nafamostat, aprotinin, citrate, and hirudin [20].…”

Study on Blood Compatibility of a Central Venous Catheter and its Pyrogen Test

“…A variety of clotting time tests is used for the detection of the coagulation system. In general,in the clotting tests,the blood compatibility of testing materials is better when the clotting time is longer,which indicates that less coagulation factorsare activated [5].In this study,thecoagulation parameters including TT, PT, APTT and Fg were measured before and after the blood of healthy human flowed through thecentral venous catheter samples,and the plateletfunction parameters including TXB2 and platelet count were also determined. All of the results showed parameters of platelet function and coagulationbefore and after the healthy human blood flowed through the central venous catheter samples were not statistically significantly changed (P> 0.05),suggestingthat the centralvenouscatheter material didnot cause changes in coagulation or plateletfunction.…”

Anticoagulation Management

“…4 The activated clotting time (ACT) is an assessment of the time it takes whole blood to clot in the presence of an activator. 5 The ACT is useful to monitor procedural anticoagulation during invasive procedures because it has a linear relationship with heparin and does not exhibit the variability at high doses that is seen with the aPTT. The ACT also has the added advantage of being an assessment of overall coagulation ability.…”

“…The ACT monitoring regimen is similar to the prolongation of the aPTT, with an ACT of 1.5 to 2.5 times baseline in a fully anticoagulated patient (or >200 seconds if no baseline was performed; normal is <150 seconds). 4,5 Rapid reversal is a major advantage to the use of heparin. Aside from the relatively short half-life of UFH as compared with other anticoagulation agents, heparin may be fully reversed pharmacologically.…”