Haemonetics TEG 6s, User Manual

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Chapter 4, Getting Started 31
Haemonetics
®
TEG
®
6s User Manual P/N 115191-IE, Manual revision: AB
TEG Analyzer Design
Principles of
design
The TEG analyzer approach to the monitoring of patient hemostasis is based
on the following:
1. The end result of the hemostasis process i s the clot.
2. The clot’s physical and developmental properties (rate, strength, and
stability) affect whether the patient will have normal hemostasis, will
hemorrhage or will develop thrombosis.
How the TEG analyzer works
Disposable assay cartridges contain all of the components necessary to allow
the analyzer to prepare samples and perform hemostasis tests.
The analyzer automatically draws the blood into the active area of the
cartridge, meters the exact amount required for the test, and mixes it with the
reagents spotted in the cartridge. The analyzer then monitors the harmonic
motion of a pendant drop of blood in response to external vibration. As the
sample transitions from a liquid state to a gel-like state during clotting, the
modulus of elasticity and resonant frequency increase. The analyzer measures
these variations in resonant frequency during clotting and lysis.The results are
displayed in a table and on a graphical tracing that reflects a hemostasis profile
of clot formation.
The resulting hemostasis profile is a measure of the time it takes for the first
measurable clot to be formed, the kinetics of clot formation, the strength of the
clot, and the breakdown of the clot, or fibrinolysis.
Figure 4-1, TEG tracing parameters
Individual points in the hemostasis profile indicate specific parameters of
patient hemostasis. These parameters – R, K, Angle, MA, and LY30 – are
indicated in the above diagram. The next section describes the TEG analyzer
parameters in more detail.
1. R: Reaction time
2. K: K-time
3.
α
: Angle
4. MA: Maximum Amplitude
5. LY30: Percent Lysis 30
minutes after MA