Postoperative acute necrotizing pancreatitis of the pancreatic remnant (POANP): a new definition of severe pancreatitis following pancreaticoduodenectomy

Background: Recent studies have suggested acute pancreatitis as a separate pancreatic-specific complication following pancreaticoduodenectomy. However, data on necrotizing pancreatitis of the pancreatic remnant is limited. This study aimed to evaluate parameters of patients undergoing completion pancreatectomy (CP) after initial pancreaticoduodenectomy (PD) and compare those with or without necrosis of the pancreatic remanent. Methods: Patients who underwent CP following PD between January 2005 and December 2017 were identified from a prospectively collected database. Perioperative parameters were recorded, and patients were divided into those with or without histological evidence of necrosis of the pancreatic remnant. Results: Postoperative acute necrotizing pancreatitis (POANP) was histologically detected in 33 (41%) of 79 patients after CP. Serum CRP levels on POD 2 and the day of revision were significantly higher in the POANP group (p < 0.001 for each). POANP was reflected by higher APACHE II and SOFA scores after PD (P < 0.001 for each). Although patients with POANP had an earlier revision, length of ICU and total hospital stay was prolonged (p < 0.001 for each). POANP was associated with more major complications (Clavien-Dindo >= 3) and more often necessitated reoperations within 30 days (p < 0.001 for each). Conclusion: Patients requiring CP following PD for POANP have an increased risk of major complications, and longer hospital stay. CRP levels, APACHE II and SOFA score, seem to correlate with the severity and might predict POANP. Universally accepted definitions with a clinically validated grading system of severity for POAP and POANP are needed to facilitate appropriate treatment strategies and enable comparison of future studies.