An Open-Label Randomized Controlled Trial Comparing Effectiveness of Aggressive Hydration Versus High-dose Rectal Indomethacin in the Prevention of Postendoscopic Retrograde Cholangiopancreatographic Pancreatitis (AHRI-PEP)

BACKGROUND: Although rectal administration of nonsteroidal anti-inflammatory drugs is recommended as the standard pharmacologic modality to prevent postendoscopic retrograde cholangiopancreatography (ERCP) post-ERCP pancreatitis (PEP), vigorous periprocedural hydration (vHR) with lactated Ringer's solution (LR) is emerging as an effective prophylaxis modality for PEP. There has been no head-to-head comparison between these 2. STUDY: This was a single-center, randomized, open-label, noninferiority, parallel-assigned, equal allocation, controlled clinical trial in a tertiary care hospital. Consecutive adults referred for ERCP, satisfying predefined inclusion criteria, underwent simple randomization and blinded allocation into 2 groups. Those allocated to vHR received intravenous LR at 3 mL/kg/h during procedure, 20 ml/kg bolus immediately afterward, and then at 3 mL/kg/h for another 8 hours. Those randomized to rectal Indomethacin received only per-rectal 100 mg suppository immediately post-ERCP. Assuming PEP of 9% in Indomethacin arm and noninferiority margin of 4%, we calculated sample size of 171 patients in each arm for 80% power and α-error 5%. Primary outcome was incidence of PEP, within 1 week, as defined by Cotton's criteria. All analysis were done by intention-to-treat. RESULTS: Between October, 2017 to February, 2018, 521 patients were assessed. In all, 352 were enrolled, 178 randomized to vHR, and 174 to per-rectal Indomethacin. Baseline details and ERCP outcomes were not different between 2 groups. PEP occurred in 6 (1.7%) overall, with 1 (0.6%) in hydration arm, and 5 (2.9%) in indomethacin arm; an absolute risk reduction of 2.3% (95% confidence interval: 0.9%-3.5%) and odds ratio of 0.19 (95% confidence interval: 0.02-1.65). Three patients developed severe PEP, all receiving indomethacin. CONCLUSIONS: vHR with LR is noninferior to postprocedure per-rectal Indomethacin for PEP prevention (ClinicalTrials.govID:NCT03629600).