Early postoperative serum hyperamylasemia: Harbinger of morbidity hiding in plain sight?

Background: The clinical significance of postoperative serum pancreatic enzyme elevation after pancreatoduodenectomy is understudied. We hypothesized that elevation in serum enzymes predicts morbidity and mortality after pancreatoduodenectomy. Methods: Retrospective review of 677 patients who underwent pancreatoduodenectomy at a single institution from 2013 to 2019. Patients were categorized based on serum enzyme concentrations. Patient characteristics, drain amylase, and outcomes among groups were compared. Results: In total, 415 of 677 patients had postoperative serum amylase concentrations measured. Of these, 243 (59%) were normal, 96 (23%) were classified as postoperative serum hyperamylasemia, and 76 (18%) were classified as postoperative acute pancreatitis. Major morbidity was lower among patients with normal enzyme concentration (10%) and higher in patients with postoperative serum hyperamylasemia (23%) and postoperative acute pancreatitis (18%) (P =.008). Patients with normal enzymes were less likely to develop postoperative pancreatic fistula (5%) compared with patients with postoperative serum hyperamylasemia (26%) and postoperative acute pancreatitis (21%) (P <.001) and less likely to develop delayed gastric emptying (9% vs 23% and 20%, respectively); P =.002. No difference in mortality was seen among groups. Conclusion: Elevated serum pancreatic enzyme concentration occurs frequently after pancreatoduodenectomy and is associated with increased postoperative morbidity. Serum enzyme concentration should be considered in management after pancreatoduodenectomy.