Comparison of clinical outcomes between aggressive and non-aggressive intravenous hydration for acute pancreatitis: a systematic review and meta-analysis

Background: Current practice guidelines for optimal infusion rates during early intravenous hydration in patients with acute pancreatitis (AP) remain inconsistent. This systematic review and meta-analysis aimed to compare treatment outcomes between aggressive and non-aggressive intravenous hydration in severe and non-severe AP. Methods: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We systematically searched PubMed, Embase and Cochrane Library for randomized controlled trials (RCTs) on November 23, 2022, and hand-searched the reference lists of included RCTs, relevant review articles and clinical guidelines. We included RCTs that compared clinical outcomes from aggressive and non-aggressive intravenous hydration in AP. Meta-analysis was performed using a random-effects model for participants with severe AP and non-severe AP. Our primary outcome was all-cause mortality, and several secondary outcomes included fluid-related complications, clinical improvement and APACHE II scores within 48 h. Results: We included a total of 9 RCTs with 953 participants. The meta-analysis indicated that, compared to non-aggressive intravenous hydration, aggressive intravenous hydration significantly increased mortality risk in severe AP (pooled RR: 2.45, 95% CI: 1.37, 4.40), while the result in non-severe AP was inconclusive (pooled RR: 2.26, 95% CI: 0.54, 9.44). However, aggressive intravenous hydration significantly increased fluid-related complication risk in both severe (pooled RR: 2.22, 95% CI 1.36, 3.63) and non-severe AP (pooled RR: 3.25, 95% CI: 1.53, 6.93). The meta-analysis indicated worse APACHE II scores (pooled mean difference: 3.31, 95% CI: 1.79, 4.84) in severe AP, and no increased likelihood of clinical improvement (pooled RR:1.20, 95% CI: 0.63, 2.29) in non-severe AP. Sensitivity analyses including only RCTs with goal-directed fluid therapy after initial fluid resuscitation therapy yielded consistent results. Conclusions: Aggressive intravenous hydration increased the mortality risk in severe AP, and fluid-related complication risk in both severe and non-severe AP. More conservative intravenous fluid resuscitation protocols for AP are suggested. Graphical Abstract: [Figure not available: see fulltext.].