title: Thrombocytopenia accompanying a reaction to protamine sulfate.
abstract: Catastrophic pulmonary vasoconstriction, an idiosyncratic reaction to protamine, occurred following cardiopulmonary bypass in a patient with mitral regurgitation. One minute following intravenous injection of 10 mg of protamine, systemic blood pressure decreased precipitously, accompanied by elevated pulmonary arterial pressure, decreased left atrial pressure, and a dilated and poorly contracting right ventricle. These changes spontaneously reversed over five minutes. Rechallenge with protamine was uneventful. Platelet count decreased from 76,000/mm3 to 12,000/mm3. Transient thrombocytopenia occurs predictably in dogs given protamine rapidly. Suggested mechanisms of idiosyncratic pulmonary vasoconstriction in patients should consider the role of the associated thrombocytopenia.
mesh_terms: D000368:Aged; D002315:Cardiopulmonary Bypass; D006350:Heart Valve Prosthesis; D006801:Humans; D007431:Intraoperative Complications; D008168:Lung / Q000098:blood supply*; D008297:Male; D008944:Mitral Valve Insufficiency / Q000601:surgery; D010976:Platelet Count; D011479:Protamines / Q000009:adverse effects*; D013921:Thrombocytopenia / Q000139:chemically induced*; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects*
chemical_list: D011479:Protamines