Intended Use - Medtronic LR-ACT Instrucciones De Uso

ACTCART_CH_EN.FM 6/1/04 9:51 am
UC199600212b ML
7 x 9 inches (177.8 x 228.6 mm)

1 INTENDED USE

For use in determining the activated clotting time of whole blood.
For In Vitro Diagnostic Use.
2 SUMMARY
The activated clotting time test was originally described by Hattersley in 1966 (Hattersley, 1966). The test and its variations
have been widely used to monitor the anticoagulant effect of heparin.
utilize either fresh whole blood or citrated whole blood. Three types of cartridges are available (Table I). The Low Range
Activated Clotting Time Cartridge, LR-ACT (catalog # 402-01) and the High Range Activated Clotting Time Cartridge,
HR-ACT (catalog # 402-03), are for use with fresh drawn whole blood, and the Recalcified Activated Clotting Time Cartridge,
RACT (catalog # 402-02) is for use with citrated whole blood. The two fresh draw ACT cartridges are distinguished by their
respective sensitivities to the anticoagulant heparin. The HR-ACT cartridge has a decreased response to heparin which
favors its use in cardiovascular surgery. The LR-ACT cartridge has increased response to heparin, which favors its use in
therapeutic heparin administration.
3 PRINCIPLES OF THE PROCEDURE
The activated clotting time test measures the clotting time of fresh whole blood activated by surface contact. Hattersley's
original procedure used diatomaceous earth as the activating agent. Diatomaceous earth exhibits differing degrees of
contact activation depending on its purity, the source of the deposit, and the particle size and shape. Activated Clotting Time
Cartridges use a specially prepared and standardized kaolin as the activating agent. This kaolin exhibits superior
characteristics in contact activation of blood coagulation and minimizes lot to lot variation in activation characteristics.
The end point of the test is the detection of clot (fibrin) formation. Medtronic Automated Coagulation Timers detect clot
formation by measuring the rate of fall of the plunger-flag mechanism contained in each cartridge channel. The plunger
assembly falls rapidly through an unclotted sample, but the fibrin web formed during clotting impedes the rate of descent.
This is detected by a photo optical system located in the cover assembly of the instrument. Automated Coagulation Timers
perform simultaneous duplicate tests using the two channel cartridge. The clotting times for each channel are displayed in
seconds following completion of the test. By depressing the front panel display switch on the ACT II
and difference of the duplicate tests can be displayed.
4 REAGENTS
Table 1 describes the cartridge reagents (0.1 ml per channel) and maximum prewarm times for the cartridges and cartridges
+ sample:
Cartridge Type Reagent
HR-ACT 12% Kaolin
0.05M CaCl
HEPES Buffer
Sodium Azide
LR-ACT 0.75% Kaolin
0.0025M CaCl
HEPES Buffer
Sodium Azide
RACT 2.2% Kaolin
0.05M CaCl
HEPES Buffer
Sodium Azide
a
HEPES (hydroxyethyl-piperazine-ethanesulfonic acid) buffer.
b
Sodium Azide is a bacteriostatic agent.
c
Kaolin concentration may vary slightly.
5 STORAGE
Store the Activated Clotting Time Cartridges from 2 °C to 25 °C (36 °F to 77 °F) for the expiration dating period indicated on
the cartridge container. Do not use if cartridge appears discolored, cracked or disfigured, or if the reagent appears to have
evaporated or be contaminated.
Do not freeze the cartridges.
Instructions for Use
231036-00
14
Table 1.
Cartridge Max. Prewarm Limits
12 hours
2
a
b
c
12 hours
2
c
12 hours
2
Medtronic Confidential
1,2,3,5,7,12
Medtronic Activated Clotting Time Cartridges
®
instrument the average
Cartridge + Sample Prewarm Limits
Non-applicable.
Perform test immediately.
Non-applicable.
Perform test immediately.
5 min
CS009
INTENDED USE
English 3