Introduction The use of antiplatelet (AP) and anticoagulation (AC) therapy after autogenous vein repair of traumatic arterial injury is controversial. The hypothesis in this study was that there is no difference in early postoperative outcomes regardless of whether AC, AP, both, or neither are used. Methods The American Association for the Surgery of Trauma (AAST) PROspective Observational Vascular Injury Treatment (PROOVIT) registry was queried from November, 2013, to January, 2019, for arterial injuries repaired with a vein graft. Demographics and injury characteristics were compared. Need for in-hospital reoperation was the primary outcome in this four-arm study, assessed with two ordinal logistic regression models (1. no therapy vs. AC only vs. AC and AP; 2. no therapy vs. AP only vs. AC and AP). Results 373 patients (52 no therapy, 88 AP only, 77 AC only, 156 both) from 19 centers with recorded Injury Severity Scores (ISS) were identified. Patients who received no therapy were younger than those who received AP (27.0 vs. 34.2, p = 0.02), had higher transfusion requirement ( p < 0.01 between all groups) and a different distribution of anatomic injury ( p < 0.01). After controlling for age, sex, ISS, platelet count, hemoglobin, pH, lactate, INR, transfusion requirement and anatomic location, there was no association with postoperative medical therapy and in-hospital operative reintervention, or any secondary outcome, including thrombosis ( p = 0.67, p = 0.22). Conclusions Neither AC nor AP alone, nor in combination, impact complication rate after arterial repair with autologous vein. These patients can be safely treated with or without antithrombotics, recognizing that this study did not demonstrate a beneficial effect.