Aprotinin and bleeding in profoundly hypothermic perfusion

Area of Science:

• Cardiovascular Surgery
• Hemostasis and Thrombosis
• Pharmacology

Background:

• Clinical observations suggested aprotinin may impair hemostasis during deep hypothermic perfusion.
• Acute Type A aortic dissection requires complex surgical intervention, often involving hypothermia.

Purpose of the Study:

• To evaluate the effect of aprotinin on blood loss and hemostatic function in patients undergoing deep hypothermic perfusion for acute Type A aortic dissection.

Main Methods:

• Retrospective analysis of 80 consecutive acute Type A dissection patients (1987-1992).
• Comparison of blood loss in patients who received aprotinin versus those who did not, particularly during deep hypothermic perfusion (<20°C).
• Analysis of re-entries, hospital deaths, and coagulation defects.

Main Results:

• Patients treated with aprotinin experienced significantly greater blood loss (1,929 ml/24h) compared to controls (837 ml/24h).
• Aprotinin group had six re-entries and a higher incidence of bleeding and thrombosis-related deaths.
• Four surviving aprotinin patients developed severe coagulation defects.

Conclusions:

• Aprotinin may inhibit essential protease enzymes crucial for maintaining blood fluidity during hypothermic low-flow states.
• Aprotinin use in profound hypothermia may lead to disseminated intravascular coagulation, platelet consumption, abnormal bleeding, and thrombotic events.
• Cautious use of aprotinin is recommended in patients undergoing profoundly hypothermic perfusion for aortic dissection surgery.