[A case of twice catastrophic pulmonary vasoconstriction-type shock induced with protamine sulfate]

A 71-year-old female was scheduled for the re-replacement of a mechanical mitral valve. After the cardiopulmonary bypass (CPB) she was administered protamine sulfate. Subsequently mean systemic blood pressure went down below 20 mmHg and central venous pressure and mean pulmonary blood pressure were above 50 mmHg, and immediately CPB was restarted as an assist device for circulation. After the second CPB, she was administered protamine sulfate again, and the same shock occurred. At last the third CPB was restarted and the third protamine administration was not undertaken after the third CPB. Although her postoperative drainage may have been relatively much more compared with cases of neutralization of heparin, postoperative course was uneventful in this patient. Administered protamine to neutralize the anticoagulat effects of heparin may often cause temporary treatable hypotension. Although protamine may rarely cause severe pulmonary vasocontriction and anaphylactoid reactions, clinical pictures become critical once these reactions occur. It is important in these cases to identify protamine as the cause of shock and avoid repeating the shocks.