Low level of postoperative plasma antithrombin III is associated with portal vein thrombosis after liver surgery.

PURPOSE Although decreased antithrombin-III (AT-III) is a risk factor for portal vein thrombosis (PVT) in patients with liver cirrhosis, the association between postoperative PVT and postoperative AT-III levels is unknown in patients undergoing hepatectomy. METHODS Patients who underwent hepatectomy between 2015 and 2018 were retrospectively analyzed. Postoperative PVT was assessed on CT at days 6-9 after hepatectomy. One-to-one propensity score (PS) matching was used to match the baseline characteristics. RESULTS Of the 295 patients included in this analysis, 19 patients (6.4%) were diagnosed with postoperative PVT. The AT-III level on postoperative day (POD) 3 predicted postoperative PVT with a sensitivity/specificity of 74%/59% (AUC, 0.644; cut-off value, 60%; p = 0.032). Multivariate analysis revealed that AT-III levels ≤ 60% on POD3 (OR, 3.01; 95% CI 1.02-8.89; p = 0.046), cirrhosis (OR, 5.88; 95% CI 1.92-18.0; p = 0.002) and right-sided hepatectomy (OR, 4.16; 95% CI 1.45-11.9; p = 0.0079) were significant risk factors for postoperative PVT. After PS matching, 56 patients with and without AT-III supplementation were analyzed. The two groups had a similar incidence of PVT (p = 0.489). CONCLUSIONS Patients with AT-III levels ≤ 60% on POD3 should be carefully followed up regarding postoperative PVT. Our results did not support the efficacy of routine AT-III supplementation for the prophylaxis of postoperative PVT.