3-2 Chapter 3: Evaluating Global Hemostasis with the Sonoclot Analyzer
Sonoclot Analyzer Quantitative Outputs
The shape of the Sonoclot Signature tracks the hemostasis process. Quantitative results are extracted from
the Signature to characterize specific aspects of hemostasis performance. These results are: ACT, Clot Rate,
and Platelet Function results. Results are displayed on the instrument’s LCD module. An understanding
of the relationship between these results and the Sonoclot Signature is useful in understanding both the
meaning of the results and the performance of the associated aspect of hemostasis performance. More
details follow.
Sonoclot Signature Phases
In each test run on the Sonoclot Analyzer, a reagent is added to a whole blood sample that initiates the
clot formation process. The resulting Sonoclot Signature can be divided into separate phases that relate
to specific aspects of hemostasis performance.
Coagulation Reaction Phase
This first phase is the period from the beginning
of the test when the sample is still a liquid until
the point when fibrinogen begins to convert
into a fibrin gel, thus increasing the viscosity of
the sample. The Sonoclot Analyzer produces
an automated result, the Activated Clotting
Time (ACT). This result is the time when the
viscosity measurement rises by 1.0 Clot Signal
units on the Sonoclot Signature.
Clot Formation Phase
This phase is the period when fibrinogen
converts to fibrin and forms a fibrin gel. The
Sonoclot Analyzer produces an automated
result, the Clot Rate. The Clot Rate is the
maximum slope of the Sonoclot Signature
during initial gel formation.
Reference Signature
Minutes
0.0
5.0
10.0
15.0
20.0
25.0
30.0
Clot
Signal
0
25
50
75
100
125
Group Description
Style Time Test Application Result Range Comment
Clot Retraction Phase
Platelet Function -
the amount of
change in the
Signature after
clot formation
Reference Signature
Minutes
0.0
5.0
10.0
15.0
20.0
25.0
30.0
Clot
Signal
0
25
50
75
100
125
Group Description
Style Time Test Application Result Range Comment
Reaction Time
Coagulation Reaction Phase
