a polymerisation disorder, whereas a reduced MCF with a normal CFT rather indicates a deficiency of clottable substrate (fibrinogen and / or platelets).Fibrinolysis is detected by the lysis of the clot (ML > 15%) or by the finding of a better clot formation (shorter CFT, greater MCF) in APTEM as compared to EXTEM. Several centres already use, in massive bleeding, a shortening of the CT in APTEM, as compared to EXTEM, as a trigger for an antifibrinolytic drug administration.
The assessment of the ROTEM® platelet analysis is carried out along the time axis (from left to right): A disturbed platelet aggregation is indicated by a decreased amplitude (curve). As causes, the intake of drugs that are influencing the platelet function or platelet dysfunctions due to e.g extracorporeal assist devices, surgery, or others have to be considered. Drugs which can influence the platelet aggregation are cyclooxygenase inhibitors (e.g. patient treatment with acetylsalicylic acid), GP IIb/IIIa receptor blockers (e.g. patient treatment with GP IIb/IIIa antagonists) or ADP receptor blocker (e.g. patient treatment with thienopyridines or direct ADP receptor antagonists). With the ROTEM® platelet differential diagnosis and the tests ADPTEM, TRAPTEM and ARATEM the reason for a decreased platelet aggregation can be determined.
In summary the ROTEM® analysis provides:
- Rapid information from the beginning of clot formation until its dissolution
- Concentration and activity of coagulation factors (incl. F XIII)
- Effects of anticoagulants like heparin or hirudin
- Fibrin generation and stabilisation
- Contribution of other drugs (e.g. plasma expanders)
- Platelet function and aggregation
- The balance between plasmatic and platelet derived contributions to haemostasis
- (Hyper-) fibrinolysis