Better Consensus Needed for Anticoagulation Use Following HN Free Flap Procedures

by Amy E. Hamaker •

Is there a preferred protocol for the postoperative use of anticoagulation after free tissue transfer in head and neck ablative procedures, particularly in relation to free flap complications?

BOTTOM LINE

There is currently no consensus in the literature on the optimal anticoagulation therapy in patients undergoing free flap reconstruction of the head and neck, and inadequate evidence to develop a standardized protocol.

Background: Free flap outcomes have improved drastically since the introduction of microvascular surgery, but postoperative complications, mostly as the result of venous thrombosis at the pedicle anastomosis, still occur. Despite routine anticoagulant and antiplatelet agent administration, most surgeons rely on anecdotal evidence based on prior use, personal outcomes, and training experiences rather than a set regimen.

Study design: Systematic literature review of 21 English-language studies.

Setting: PubMed, Ovid, and Cochrane databases.

Synopsis: Across all studies, outcome measure homogeneity was present, but anticoagulation medication administration protocols varied widely. Anticoagulation regimens included heparin, LMWH, aspirin, dextran-40, prostaglandin E1 (PGE1), or no anticoagulation. There were 231 incidences of free flap failure (4.4%) across all studies; individual study rates ranged from 0.0% to 10.7%. Thrombosis and hematoma incidence across all studies were 4.5% and 2.2%, respectively, and ranged from 0.0% to 10.4% and 0.6% to 7.2%, respectively, in individual studies. Aspirin showed the lowest rate of free flap failure and thrombosis and had an acceptable hematoma rate when compared to other options, but dosage (75 mg to 325 mg) and administration route (oral, rectal) were inconsistent. The highest free flap failure and thrombosis rates and lowest hematoma rate were with dextran. The overall flap failure rate for heparin or LMWH was similar to published and accepted rates (between 2% and 9%). PGE1 had flap failure, thrombosis, and hematoma formation rates comparable to other therapies. Limitations included heterogeneous medication use and treatment protocols, small sample sizes, and a lack of specific randomized controlled studies.

Citation: Barton BM, Riley CA, Fitzpatrick JC, et al. Postoperative anticoagulation after free flap reconstruction for head and neck cancer: a systematic review. Laryngoscope. 2018;128:412–421.