What is an appropriate treatment for severe heparin toxicity?

The appropriate treatment for severe heparin toxicity is the use of protamine sulfate intravenously. Protamine sulfate is a specific antidote for heparin; it binds to heparin and neutralizes its anticoagulant effect. This is particularly important in cases of heparin toxicity where there is a risk of severe bleeding or other complications. Administering protamine sulfate effectively allows the clinician to reverse the effects of heparin, thereby restoring normal hemostasis and mitigating the risks associated with excessive anticoagulation.

In contrast, administering vitamin K is ineffective for heparin toxicity as it is used to counteract the effects of vitamin K antagonists like warfarin, not heparin. Increasing the heparin dosage or continuing its administration would only exacerbate the toxicity and heighten the risk of bleeding, making these options contraindicated in the context of heparin overdose. Thus, using protamine sulfate is the recognized and correct approach to manage severe heparin toxicity.