Pentasaccharide FondaparinuxArixtra®

The pentasaccharide fondaparinux (Arixtra®) is a synthetically produced 5-sugar that inhibits factor Xa in the coagulation cascade via antithrombin (a naturally occurring blood clotting inhibitor in the body). The drug is administered by subcutaneous administration (subcutaneously, see c.). Once absorbed into the bloodstream, it binds to antithrombin.

The substance is excreted via the kidneys. The drug is administered at the earliest six hours after an operation. A cross-reaction with HIT type II antibodies could not be detected so far. You can find out more about Arixtra® under our topic: Arixtra®Authorized for patients with a high-risk orthopedic and trauma surgery profile.

Acetylsalicylic acid

The acetylsalicylic acid is also known under the names ASS or Aspirin ®. Its function is to interfere with platelet function (platelet aggregation inhibitor). The administration of ASA alone is not sufficient for the prophylaxis of a thrombus, especially in the deep veins of the legs.

Oral anticoagulants

Oral anticoagulants include vitamin K antagonists such as Marcumar®. Vitamin K is an important cofactor of enzymes that trigger and regulate the blood coagulation cascade. The onset of action is delayed.

It is mainly used as long-term prophylaxis.The following laboratory parameters must be checked regularly: As a measure of the extrinsic path of the blood coagulation cascade, the quick value or thromboplastin time TPZ describes the time to coagulation. Nowadays, the quick value is increasingly being replaced by the INR value (International Normalized Ratio), an international standardization of the quick value. The INR should be between 2.0 and 3.0 to ensure optimal protection.

Quick value/thromboplastin time TPZ
INR

Thrombin inhibitors

Thrombin is the factor II of the blood clotting cascade and, as enzyme, splits the precursor fibrinogen into fibrin (factor I of the clotting cascade), which ultimately forms the blood clot (white thrombus). It also activates other clotting factors. The thrombin inhibitor hirudin does not show any cross-reactions with HIT type II antibodies, so that the active substance is mainly used in patients with known HIT type II for the prevention of thromboembolism.