Characterization of postoperative acute pancreatitis (POAP) after distal pancreatectomy

Postoperative acute pancreatitis has recently been reported as a specific complication after pancreatoduodenectomy. The aim of this study was to characterize postoperative acute pancreatitis after distal pancreatectomy.

We analyzed the outcomes retrospectively of 368 patients who underwent distal pancreatectomies during the period January 2016 to December 2019. Postoperative acute pancreatitis was defined as an increase of serum amylase activity greater than our laboratory normal upper limit on postoperative days 0 to 2. We assessed the incidence of postoperative acute pancreatitis after distal pancreatectomy and examined possible predictors of postoperative acute pancreatitis and relationships of postoperative acute pancreatitis with postoperative pancreatic fistula.

The rates of postoperative acute pancreatitis and postoperative pancreatic fistula after distal pancreatectomy were 67.9% and 28.8%, respectively. Patients who developed postoperative acute pancreatitis experienced an increased rate of severe morbidity (18.4 vs 9.3%; P = .030). Neoadjuvant therapy (odds ratio 0.28, 0.09-0.85; P = .025), age ≥ 65 y (odds ratio 0.34, 0.13-0.85; P = .020), duct size (odds ratio 0.02, 0.002-0.47; P = .013), pancreatic thickness (odds ratio 3.4, 1.29-8.9; P = .013), resection at the body-tail level (odds ratio 4.3, 1.15-23.19; P = .041), and neuroendocrine histology (odds ratio 1.14, 1.06-3.90; P = .013) were independent predictors of postoperative acute pancreatitis. Furthermore, postoperative acute pancreatitis was an independent predictor of postoperative pancreatic fistula (odds ratio 5.8, 2.27-15.20; P < .001). Postoperative pancreatic fistula occurred in 37% of patients who developed postoperative acute pancreatitis. Patients developing postoperative acute pancreatitis alone demonstrated a statistically significantly increased rate of biochemical leakage and bacterial contamination in the peripancreatic drainage fluid.

Postoperative acute pancreatitis is a frequent event after distal pancreatectomy and, despite its close association with postoperative pancreatic fistula, evidently represents a separate phenomenon. A universally accepted definition of postoperative acute pancreatitis that applies to all types of pancreatic resections is needed, because it may identify patients at greater risk for additional morbidity immediately after pancreatic resections.