Modification of prophylactic anticoagulation regimen reduces the incidence of thrombotic complications after venous reconstruction.
Authors: Pogorelova Yulia A. , Frantsiyants Elena M. , Surikova Ekaterina I. , Katelnitskaya Oksana V. , Duritskiy Maksim N. , Kharagezov Dmitry A. , Milakin Anton G. , Stateshny Oleg N. , Kit Oleg I. 
Published: June 2022

e16250 Background: Surgical treatment for pancreatic cancer (PC) with venous reconstruction is associated with a high risk of venous thrombosis. The purpose of this study was to analyze the dynamics of the blood fibrinolytic system in the postoperative period in PC patients after venous reconstruction. Methods: The study included patients with PC (T3N0-1M0), mean age 63 years. Patients of the main group (n = 11) underwent pancreaticoduodenal or corporocaudal resection with venous reconstruction (portal and superior mesenteric veins), mesenteric cross-clamping time 7-40 minutes (average 23 minutes). Patients of the control group (n = 11) received similar surgical treatment without venous resection. All patients received postoperative prophylactic anticoagulation: standard nadroparin 0.4 ml once a day in the control group and a modified regimen of nadroparin 0.1 ml per 10 kg of body weight per day in a low bleeding risk in the main group. Levels of tPA, uPA, PAI-1 and suPAR, and tPA-act, uPA-act, and PAI-1-act activity were determined in the blood plasma by ELISA (Technoclone, Austria; R&D Systems, USA) on days 1-3, 5-7 and 8-14 after surgery. Results: No thrombotic complications were registered in the main group during the 30-day observation period, while 2 patients (18.2%) in the control group were diagnosed with distal venous thrombosis on days 10-14. The frequency of hemorrhagic complications was similar in both groups (9.1% vs 9.1%). Levels of PAI-1 decreased by 2.4 times in both groups on days 1-3 after surgery, tPA increased by 1.7 times (p < 0.01), and tPA-act increased in the main group by 2.9 times. On days 5-7, no changes were registered in the control group, while patients of the main group showed decreased tPA-act by 3.2 times and elevated suPAR and PAI-1 by 2.2 times (p < 0.01) and PAI-1-act by 3.6 times. However, levels of PAI-1-act decreased by 2.2 times (p < 0.01) in the main group on days 8-14, and in control group PAI-1 increased by 2.4 times (р < 0.05). Thus, patients in the main group had 2.4 times higher levels of tPA on days 1-3, compared to the control group, and higher suPAR on days 5-7 (by 1.8 times, p < 0.01), PAI-1 and PAI-1-act by 2.0 times (p < 0.01), and higher tPA (by 4.4 times) on days 8-14. Conclusions: The proposed scheme of prophylactic anticoagulation showed its efficacy and safety. It activated fibrinolysis 1-3 days after surgery. Further on, we could observe signs of enhanced prothrombotic and pro-inflammatory state despite the ongoing anticoagulant therapy, which, however, was not manifested by thrombotic complications. Levels of tPA increased significantly by days 8-14 after venous reconstruction and intestinal ischemia, while inhibitor levels remained high, which can be considered a change in the balance towards activation of fibrinolysis and enhancement of anti-inflammatory processes.