Kaolin Activated Clotting Time - Abbott i-STAT 1 System Manual

The i-STAT Kaolin Activated Clotting Time test,
®
activation of the coagulation cascade.
In traditional ACT tests, coagulation is initiated by mixing a whole blood sample with a particulate activator,
and complete activation is indicated when extensive or localized clots form as activated thrombin converts
fibrinogen to fibrin. These clots are mechanically detected.
The i-STAT ACT test is similar to traditional ACT tests except that the endpoint is indicated by the
Kaolin
conversion of a thrombin substrate other than fibrinogen and an electrochemical sensor is used to indicate
the event of this conversion. The substrate used in the electrogenic assay has an amide linkage that mimics
the thrombin-cleaved amide linkage in fibrinogen.
The substrate is H-D-phenylalanyl-pipecolyl-arginine-p-amino-p-methoxydiphenylamine which has the
structure:
Phenylalanine - Pipecolic acid - Arginine -- NH - C
Thrombin cleaves the amide bond at the carboxy- terminus of the arginine residue (denoted by the two
dashes) because the bond structurally resembles the thrombin-cleaved amide linkage in fibrinogen. The
product of the thrombin-substrate reaction is the electrochemically inert tripeptide Phenylalanyl - Pipecolyl
- Arginine and the electroactive compound
electroactive compound is detected amperometrically, and the time of detection is measured in seconds.
The test reports the Activated Clotting Time (ACT) in seconds.
The i-STAT ACT test is calibrated to match the Hemochron Celite FTCA510 using prewarmed reagent
Kaolin
tubes. However, users of the i-STAT
to report ACT results as calibrated against the Hemochron Celite ACT using non-prewarmed (ambient
temperature) tubes. This customization affects the Patient path only, and will not be applied to the Control
or the Proficiency Testing pathway.
The customization in effect (prewarm or non-prewarm calibration mode) is identified on the analyzer screen
as PREWRM or NONWRM, respectively. Please note that different locations within a given hospital may
utilize different customization profiles. Prior to patient sample testing, ensure the appropriate calibration
mode is employed. For a comprehensive discussion of this customization feature, please see the Technical
Bulletin entitled "ACT Test Result Calibration Options: PREWARMED vs. NON-PREWARMED Result
Calibration Modes for the i-STAT
If results appear inconsistent with the clinical assessment, the patient sample should be re-tested using
another cartridge.
Intended Use
The i-STAT Kaolin Activated Clotting Time (
blood, and is used to monitor high-dose heparin anticoagulation frequently associated with cardiovascular
surgery.
Rev. Date: 31-Jan-12

KAOLIN ACTIVATED CLOTTING TIME/

( ACT)
KAOLIN
Kaolin
1
NH
3
1 analyzer may choose to customize their individual i-STAT locations
®
1 Analyzer".
®
ACT) test is an in vitro diagnostic test that uses fresh, whole
Kaolin
Art: 715878-00M
ACT, is a measure of the time required for complete
H - NH - C H - OCH
6 4 6 4
- C H - NH - C H - OCH
+
6 4 6 4
3
. The formation of the
3