Assessment of Perioperative Protamine Reactions in Patients With Fish Allergies: A Retrospective Observational Study.

Objectives: To retrospectively assess the incidence and severity of perioperative protamine reactions in adult patients with documented history of fish allergy.

Design: Retrospective observational study.

Setting: Large academic tertiary referral center.

Participants: Adults with fish allergies undergoing surgeries involving protamine, between January 1, 2008, and March 1, 2018.

Interventions: Perioperative protamine administration in patients with documented fish allergy.

Measurements And Main Results: Perioperative protamine and anaphylactic reactions were reviewed. A diagnosis of anaphylaxis or protamine reaction was based on clinical suspicion, perioperative events, and postoperative evaluations. Among 214 patients, 2 cases (<1%) of anaphylaxis or protamine reactions occurred. Cardiac procedures were most common (67%). The median intraoperative heparin dosage was 46,000 IU, and the median protamine dosage was 310 mg. Nearly all patients (99%) were admitted to the intensive care unit postoperatively, with a median hospital stay of 6.5 days (interquartile range, 5.2-14.6 days). There were 3 deaths (1%) within 30 days, and 15 (7%) within 1 year.

Conclusions: The study findings suggest that in patients with a history of fish allergy, cross-reactivity with protamine is unlikely, as anaphylaxis and/or protamine reactions were rare in this patient population in the perioperative environment. Based on these findings, this study does not recommend avoiding protamine solely based on a history of fish allergy when heparin reversal is required during surgery.