Bilateral spontaneous, simultaneous lower extremity hematomas in a patient on dalteparin

Bleeding related to low-molecular-weight heparins (LMWHs) is typically described as an excess of minor bleeding; however, several reports of spontaneous major bleeding have been noted.

A 58-year-old female presented to the hospital with bilateral spontaneous lower extremity hematomas which rapidly enlarged. CT studies demonstrated active arterial extravasation from small vessels at multiple sites within each leg with no dominant feeding artery identified on either side. She required multiple transfusions, administration of protamine, fresh frozen plasma (FFP), recombinant activated Factor VII and eventual surgery.

Dalteparin provides an effective and economical method of anticoagulation, however there is a risk of significant, spontaneous arterial hemorrhage even in the absence of risk factors.

Dalteparin can cause major spontaneous bleeding from multiple arterial sources.