Postoperative serum hyperamylasemia (POH) predicts additional morbidity after pancreatoduodenectomy: It is not all about pancreatic fistula

Abstract

BackgroundThe association between postoperative serum hyperamylasaemia (POH) and morbidity has been hypothesized but rarely explored once occurring with or without (POH-exclusive) a combined postoperative pancreatic fistula (POPF). MethodsAnalysis of patients who consecutively underwent pancreaticoduodenectomy from 2016 to 2020. POH was defined as serum amylase activity greater than the institutional upper limit of normal (52 U/L), persisting within the first 48 hours postoperatively (postoperative day [POD] 1 and 2). ResultsAmong 852 patients, 15.8% developed POH-exclusive. Compared with patients without POH or POPF (64.3%), they showed a significantly higher postoperative burden (Clavien-Dindo ≥II: 52.6% vs 30.8%) with increased rates of bacteraemia (12.6% vs 6%), pleural effusion (13.3% vs 5.3%), postpancreatectomy haemorrhage (13.3% vs 7.5%), postpancreatectomy acute pancreatitis (PPAP) (10.3% vs 0%), and organ site infections (18.5% vs 10.9%; all P < .05). A total of 13.8% experienced POH with POPF leading to the worse outcome. The combined occurrence of POH with POPF led to a shorter median time to morbidity (3 PODs, 95% confidence interval [CI] 2.2–3.7 vs 6 PODs, 95% CI 4.2–8; P < .001) than patients experiencing POPF-exclusive (5.9%). In all, 46.6% of POH patients developed POPF. Body mass index (BMI) (odds ratio [OR] 1.1), male sex (OR 2.1), increased drain fluid amylase on POD 1 (OR 1.001), and increased C-reactive protein (OR 1.01) were independent risk factors for POPF once POH has occurred. ConclusionPOH has relevant postoperative clinical implications, independently from POPF occurrence. Developing POH with POPF leads to an earlier onset of higher postoperative burdens. Once POH is diagnosed, risk factors for additional POPF could identify patients who may benefit from additional surveillance, specific drains protocols, and preventive strategies.