The primary objectives in assessing the bleeding risk of patients:
- Preoperatively, identify pre-existing bleeding disorders or patients at a higher risk for bleeding
- Recognize compromised hemostasis (haemostasis) in bleeding patients, during and after surgery
- Monitor treatment in these situations
A thorough clinical bleeding history, using a detailed questionnaire and a physical examination, is complemented by laboratory tests and point-of-care (POC) tests.32
These tests are carried out preoperatively. Initial screening investigations include complete blood count (CBC), activated partial thromboplastin time (aPTT) and prothrombin time (PT). Patients with abnormal results require further investigation:32
- If a defect of primary hemostasis is suspected, the bleeding time should be performed, followed by platelet function tests (such as aggregometry and measurement of von Willebrand factor)
- If coagulation seems to be affected, clottable fibrinogen, thrombin time (TT) and individual coagulation factors should be measured
- If excessive fibrinolysis is suspected, fibrin and fibrinogen degradation products (e.g. D-dimers) should be measured.
Point-of-care (POC) testing takes place at or near the patient, outside the conventional laboratory setting. It is a valuable tool in an emergency situation or in perioperative bleeding because POC devices provide rapid results, which helps direct appropriate and targeted therapy.33
Two point-of-care devices allow a rapid and global evaluation of coagulation by assessing the viscoelastic properties of native blood:
- Thromboelastography (TEG®) analyzes whole blood coagulation and fibrinolysis by assessing the change in clot strength over time33
- Rotation thromboelastometry (ROTEM®) is an enhancement of classical thromboelastography, with minor changes in how the device works.
These POC devices are widely used to monitor coagulation and breakdown of the clot (lysis) in cardiac surgery, liver transplantation, trauma and obstetrics.32-33
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