2023 FSA Podium and Poster Abstracts
P047: ANAPHYLACTIC REACTION TO PROTAMINE DURING CARDIAC SURGERY REQUIRING CARDIAC MASSAGE AND REINSTITUTION OF CARDIOPULMONARY BYPASS
David T McDougal, DO1; Harshvardhan Rajen, MD1; Jessica Alonso, MD1; Jason Hall, MD2; 1HCA Florida Kendall; 2HCA Florida Aventura
Intro/Background: Protamine sulfate is a polypeptide commonly used to reverse heparin anticoagulation during cardiac surgery. Allergic reactions to protamine are known, although life-threatening reactions are rare. We report the case of an anaphylactic reaction to protamine that occurred during coronary artery bypass graft (CABG) surgery that required reheparinization and reinstitution of cardiopulmonary bypass. We review risk factors of this adverse reaction and our perioperative management.
Methods/Results (Case): A 67 year old male with past medical history of hypertension was brought into our facility for STEMI and found to have multivessel coronary artery disease requiring surgical intervention. During the surgery, after the cannulas for cardiopulmonary bypass were removed, protamine was administered over 10 minutes and hemostasis was achieved. Shortly thereafter, the patient became hypotensive, bradycardic, and pulmonary artery pressures increased. It was suspected that the patient was experiencing an anaphylactic reaction to the protamine. Medications administered included increasing vasopressors, calcium chloride, and epinephrine but the patient continued to decompensate. It was decided to administer additional heparin and reinstitute cardiac bypass. The chest was reopened, cardiac massage was performed and upon arresting the heart, the patient hemodynamically stabilized. Cardiac function returned and all vasopressors and inotropes were stopped. The heart was arrested for about 30 minutes. The patient was successfully weaned off cardiopulmonary bypass without reversal and brought to the critical care unit. Postoperatively the patient continued to bleed from the sternal wound. After evaluation by the surgeon, the patient was brought for emergency re-exploration of the chest. An arterial bleed was found at a branch of the right coronary artery, which likely occurred during reinstitution of cardiopulmonary bypass or in the brief period of manual open chest compressions used to maintain blood pressure during repeat cannulation. Following hemostasis, patient was brought back to critical care unit and postoperative care continued without additional complications.
Discussion: Protamine is a strongly cationic polypeptide that reverses the anticoagulant effects of heparin. Protamine combines with heparin to form a salt with no anticoagulation properties. It is used in heparin reversal after the removal of cardiopulmonary bypass, after dialysis, invasive vascular procedures and acute strokes. Protamine is often administered slowly or a test dose is given in order to detect any adverse reactions. Risk factors include history of past protamine exposure, vasectomy, fish allergies, and insulin dependent diabetes. The most common reaction to protamine administration is an anaphylactic response. This can be observed as hypotension, bronchoconstriction, bradycardia, and pulmonary hypertension. Incidence of major adverse reactions during cardiac surgical procedures range from 0.28% to 2.6%, although some literature reports up to 10.6%. Treatment includes steroids, albuterol, antihistamines, vasopressors, fluid administration, and echocardiography for monitoring cardiac function. If symptoms are refractory to these treatments, cardiac massage and reinstitution of cardiopulmonary bypass can be attempted.
Conclusion: Although new medications for anticoagulation and reversal during CABG and cardiopulmonary bypass are being researched, the gold standard remains heparin and protamine. Physicians administering protamine must be vigilant for signs of reaction and communicate with the surgical team to achieve the best outcome.