Safety of pancreatic surgery with special reference to antithrombotic therapy: A systematic review of the literature

BACKGROUND: Postpancreatectomy hemorrhage (PPH) is the most severe type of complication after pancreatic surgery, although the effect of antithrombotic therapy (ATT) on PPH is largely unknown. The safety and efficacy of chemical thromboprophylaxis for venous thromboembolism (VTE) remains controversial. AIM: To elucidate the effect of ATT on PPH. METHODS: Published articles between 2013 and 2020 were searched from PubMed and Google Scholar, and after careful reviewing of all studies, studies concerning ATT and pancreatic surgery were included. Data such as study design, type of surgical procedures, type of antithrombotic drugs, and surgical outcome were extracted from the studies. RESULTS: Nineteen published articles with a total of 37863 patients who underwent pancreatic surgery were included in the systematic review. Fourteen were cohort studies, with only three being prospective in nature. Two studies demonstrated that in patients receiving chronic ATT, which were mostly managed by heparin bridging, the risk of PPH was higher compared with those without ATT, and one study showed that patients with direct-acting oral anticoagulants managed by heparin bridging had significantly higher postoperative bleeding rates than others. The remaining six studies reported that pancreatic surgery can be safely performed in patients receiving chronic ATT, even under preoperative aspirin continuation. Concerning chemical thromboprophylaxis for VTE, most studies have shown a potentially high risk of PPH in patients undergoing chemical thromboprophylaxis; however, its effectiveness against VTE has not been statistically demonstrated, particularly among Asian patients. CONCLUSION: Pancreatic surgery in chronically ATT-received patients can be safely performed without an increase in the occurrence of PPH, although the safety and efficacy of chemical thromboprophylaxis for VTE during pancreatic surgery is still controversial. Further investigation using reliable studies with good design is required to establish definite protocols or guidelines.