Explanation: Although heparin-induced thrombocytopenia (HIT) is rare in children, it is most common after open heart surgery in infants who have been previously exposed to unfractionated heparin. Because this child has evidence of thrombosis as well, the unfractionated heparin must be discontinued while assessing for HIT, and another form of anticoagulation must be initiated to prevent further thrombotic complications. Enoxaparin is a low-molecular-weight heparin (LMWH)and has cross reactivity with unfractionated heparin. Warfarin cannot be initiated without a bridge with another anticoagulant. Removing the femoral catheter is not emergent and may not be necessary because the thrombus is nonocclusive.
