[Complications caused by protamine. 2. Therapy and prevention]

Area of Science:

• Pharmacology and Toxicology
• Cardiovascular Medicine
• Anaphylaxis Research

Context:

• Protamine sulfate is crucial for reversing heparin anticoagulation but can cause severe anaphylactic/anaphylactoid reactions.
• These reactions present as hypotension, vasodilation, and right ventricular dysfunction, complicating surgical procedures.
• Current treatment and prevention strategies for protamine reactions are limited and often ineffective.

Purpose:

• To review and summarize current approaches to treating and preventing protamine-induced anaphylactic/anaphylactoid reactions.
• To evaluate the efficacy of various symptomatic treatments and prophylactic measures.
• To identify potential future therapeutic targets for preventing these adverse events.

Summary:

• Treatment of protamine reactions is symptomatic, addressing hypotension with volume infusion and catecholamines, and improving coronary perfusion in cases of right ventricular dysfunction.
• Prevention is challenging due to the lack of reliable diagnostic tests for identifying susceptible individuals; slow protamine infusion and avoiding hypovolemia are recommended.
• General prophylaxis with H1/H2 antagonists is not justified, and while alternatives like prostacyclin or hexadimethrine exist, their use is situational. Thromboxane receptor antagonists show future promise.

Impact:

• Highlights the limitations of current protamine reaction management, emphasizing symptomatic care over prophylaxis.
• Informs clinical practice regarding the cautious use of protamine and the limited options for prevention.
• Suggests future research directions, particularly in pharmacologic prevention targeting pathways like thromboxane.