An assessment of pharmacologic deep vein thrombosis prophylaxis on head and neck free flap outcomes

Objective To compare head and neck free flap outcomes based on usage of pharmacologic deep vein thrombosis (DVT) prophylaxis. Study design Multicenter retrospective study including patients from January 1, 2010 to December 31, 2023. Setting Sixty-eight healthcare organizations in the United States. Methods Patients older than 18 years with head and neck cancer who underwent either non-bony or bony free flap reconstruction were grouped according to whether they received DVT prophylaxis or not on the same day of surgery or postoperatively. Primary outcomes were compared between the groups which included flap failure, the need for blood vessel repair, and flap revision. Results On the same day of surgery, there was no significant difference for non-bony reconstruction for flap failure (RR: 0.95; 95% CI: 0.75–1.20: P : 0.66), blood vessel repair (RR: 0.96; 95% CI: 0.82–1.12; P : 0.60), or flap revision (RR: 0.96; 95% CI: 0.84–1.09; P : 0.53). No differences were also observed for bony reconstruction. Postoperatively, there was an increased rate of flap failure and flap revision for both non-bony ([RR: 0.73; 95% CI: 0.69–0.79; P : <0.0001], [RR: 0.71; 95% CI: 0.66–0.77; P : <0.0001]) and bony reconstruction ([RR: 0.66; 95% CI: 0.59–0.75; P : <0.0001], [RR: 0.66; 95% CI: 0.57–0.73; P : <0.0001]) in the patient groups that did not get DVT chemoprophylaxis. Conclusion Pharmacologic DVT prophylaxis administration in the postoperative period for both bony and non-bony head and neck free flaps is associated with a decreased risk of flap failure and revision. Perioperative administration on the day of surgery had no impact on outcomes.