Randomized controlled trial: neostigmine for intra-abdominal hypertension in acute pancreatitis

BACKGROUND: Intra-abdominal hypertension (IAH) in acute pancreatitis (AP) is associated with deterioration in organ function. This trial aimed to assess the efficacy of neostigmine for IAH in patients with AP. METHODS: In this single-center, randomized trial, consenting patients with IAH within 2 weeks of AP onset received conventional treatment for 24 h. Patients with sustained intra-abdominal pressure (IAP) ≥ 12 mmHg were randomized to receive intramuscular neostigmine (1 mg every 12 h increased to every 8 h or every 6 h, depending on response) or continue conventional treatment for 7 days. The primary outcome was the percent change of IAP at 24 h after randomization. RESULTS: A total of 80 patients were recruited to neostigmine (n = 40) or conventional treatment (n = 40). There was no significant difference in baseline parameters. The rate of decrease in IAP was significantly faster in the neostigmine group compared to the conventional group by 24 h (median with 25th–75th percentile: −18.7% [− 28.4 to − 4.7%] vs. − 5.4% [− 18.0% to 0], P = 0.017). This effect was more pronounced in patients with baseline IAP ≥ 15 mmHg (P = 0.018). Per-protocol analysis confirmed these results (P = 0.03). Stool volume was consistently higher in the neostigmine group during the 7-day observational period (all P < 0.05). Other secondary outcomes were not significantly different between neostigmine and conventional treatment groups. CONCLUSION: Neostigmine reduced IAP and promoted defecation in patients with AP and IAH. These results warrant a larger, placebo-controlled, double-blind phase III trial. Trial registration Clinical Trial No: NCT02543658 (registered August /27, 2015). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13054-022-03922-4.