Substitution of antithrombin III.

Area of Science:

• Thrombosis and Hemostasis
• Pharmacology
• Critical Care Medicine

Background:

• Antithrombin III (AT III) is a key regulator of coagulation.
• Deficiencies in AT III, both inherited and acquired, increase thrombotic risk.
• Conditions like liver cirrhosis, nephrotic syndrome, polytrauma, and sepsis can lead to acquired AT III deficiency.

Purpose of the Study:

• To outline the indications for AT III substitution therapy.
• To describe the dosing principles for AT III substitution.
• To highlight the importance of normalizing AT III levels in thrombotic complications.

Main Methods:

• Review of clinical indications for AT III substitution.
• Description of standard initial dosing (1 U/kg) to achieve a 1.5% rise in plasma AT III.
• Discussion of dose adjustments based on AT III turnover rates.

Main Results:

• AT III substitution is indicated in inherited deficiency with thrombosis, surgery, or pregnancy complications.
• Substitution may be necessary in acquired deficiency (e.g., liver cirrhosis, nephrotic syndrome) with thrombotic events.
• Therapy is also considered in polytrauma, sepsis, DIC, liver failure, and toxemia.

Conclusions:

• AT III substitution is vital for managing thrombotic risks in various deficiency states.
• Dosing requires careful consideration of individual AT III turnover.
• Achieving and maintaining adequate plasma AT III levels is essential for preventing and treating thrombosis, particularly in DIC.