Protamine Sulfate Infusion's Rare Side Effect: Severe Hypertension, Tachycardia

Protamine sulfate is an agent used to antagonize the anticoagulant effect of heparin. Some side effects may occur during the administration of this agent. The most common side effects are hypotension, bradycardia, pulmonary vasoconstriction, and hypoxemia. However, hypertension and tachycardia may also occur, albeit rarely. Here, we present a case in which hypertension and tachycardia developed during protamine sulfate infusion in open-heart surgery.