In thromboelastography, the tracing measures which sequence of events?

In thromboelastography, the tracing measures which sequence of events?

• A. Clot onset, aggregation, clot strength
• B. Clot onset, clot strength, fibrinolysis
• C. Aggregation, clot onset, clot strength
• D. Clot onset, clot strength, fibrinolysis

Answer: (B)

Thromboelastography shows the evolving clot from its first appearance to its eventual breakdown, so the trace follows onset of clotting, the development of clot strength, and finally fibrinolysis if it occurs. The initial moment is the onset of clot formation (R time), when fibrin strands start to form. Next comes the strengthening of the clot as fibrin polymerization and platelet interaction increase firmness (reflected in the rate of clot growth and the maximum amplitude). If the clot is later dissolved, fibrinolysis causes a decline in clot firmness over time, captured by lysis parameters. Aggregation isn’t treated as a separate discrete step on the TEG trace; the trace’s progression is primarily onset, strength, and breakdown. Therefore, the best sequence is clot onset, clot strength, then fibrinolysis.

Thromboelastography shows the evolving clot from its first appearance to its eventual breakdown, so the trace follows onset of clotting, the development of clot strength, and finally fibrinolysis if it occurs. The initial moment is the onset of clot formation (R time), when fibrin strands start to form. Next comes the strengthening of the clot as fibrin polymerization and platelet interaction increase firmness (reflected in the rate of clot growth and the maximum amplitude). If the clot is later dissolved, fibrinolysis causes a decline in clot firmness over time, captured by lysis parameters. Aggregation isn’t treated as a separate discrete step on the TEG trace; the trace’s progression is primarily onset, strength, and breakdown. Therefore, the best sequence is clot onset, clot strength, then fibrinolysis.