Thrombin-soaked coils: estimation of thrombin dose

Area of Science:

• Interventional Radiology
• Biomaterials Science
• Biochemistry

Background:

• Thrombin-soaked coils are utilized as embolic agents for various medical conditions.
• High doses of intravascular thrombin may pose risks.
• Estimating thrombin dosage with transcatheter coils is essential for safe and effective treatment.

Purpose of the Study:

• To quantify the thrombin absorption by steel coils used in transcatheter embolization.
• To determine the impact of thrombin concentration and soaking orientation on absorption.
• To establish optimal soaking parameters for thrombin-soaked coils.

Main Methods:

• An in vitro experiment was conducted to measure thrombin absorption.
• Steel coils (8 mm x 5 cm, 0.038-inch) were soaked in varying thrombin concentrations (10,000 U/10 mL and 20,000 U/10 mL).
• Thrombin absorption was assessed based on coil orientation (vertical vs. horizontal) and soaking time.

Main Results:

• Coils soaked in higher thrombin concentrations (20,000 U/10 mL) absorbed significantly more thrombin (average 71.6 U) compared to lower concentrations (10,000 U/10 mL, average 38.4 U).
• Maximum single-coil absorption reached 45.6 U and 88.2 U for the respective concentrations.
• Thrombin absorption plateaued after 1 minute of soaking.
• Vertical orientation maximized thrombin absorption, while horizontal orientation resulted in minimal absorption.

Conclusions:

• The dose of thrombin absorbed by steel coils is dependent on the soaking solution concentration and coil orientation.
• Vertical orientation and sufficient soaking time (≥1 minute) are critical for maximizing thrombin absorption.
• These findings provide valuable data for standardizing the preparation of thrombin-soaked coils as embolic agents.