Selective and Continuous Transarterial Heparin Infusion: Postmicrosurgical Therapy of Lower Leg Reconstruction for Cases with Recipient Artery Damage.

Background: Microsurgical lower extremity reconstruction is challenging because of high incidence of vascular thrombosis compared to microsurgical head and neck reconstruction. The risk of vascular pedicle thrombosis increases, if patients have arterial sclerosis or intimal dissection at the recipient artery. We performed selective and continuous transarterial heparin infusion for postoperative anticoagulant therapy.

Methods: Fifteen patients (10 men and 5 women; mean age of 55.1 years; range of 16-86 years) received lower leg reconstruction using free flap. Postoperatively, a catheter was inserted into the femoral artery during surgery. Heparin infusion was performed through the catheter as a postoperative therapy for patients who had a risk factor of vascular pedicle thrombosis. Until two days post-operation, heparin was started between 5,000 and 10,000 IU per day. In postoperative days 3 and 4, half of the initial dose of heparin was administered. In postoperative days 5 and 6, 25% of the initial dose of heparin was administered.

Results: Recipient arteries were the posterior tibial (n=11), anterior tibial (n=2), lateral circumflex femoral (n=1), and medial sural (n=1) arteries. Thirteen of the 15 cases showed arterial sclerosis or intimal dissection at the recipient artery. There was no case of vascular thrombosis. Hematoma formation at flap recipient was observed in four cases. Their initial heparin dose was than 8.5±1.7 U/kg/h.

Conclusion: Continuous transarterial heparin infusion was an effective anticoagulant therapy for the patients who had received free tissue transfer to a lower extremity. The initial dose of heparin should not exceed 6.5 U/kg/h.