Planned Versus On-Demand Relaparotomy Strategy in Initial Surgery for Non-occlusive Mesenteric Ischemia.

BACKGROUND: There has been insufficient evidence regarding a treatment strategy for patients with non-occlusive mesenteric ischemia (NOMI) due to the lack of large-scale studies. We aimed to evaluate the clinical benefit of strategic planned relaparotomy in patients with NOMI using detailed perioperative information. METHODS: We conducted a multicenter retrospective cohort study that included NOMI patients who underwent laparotomy. In-hospital mortality, 28-day mortality, incidence of total adverse events, ventilator-free days, and intensive care unit (ICU)-free days were compared between groups experiencing the planned and on-demand relaparotomy strategies. Analyses were performed using a multivariate mixed effects model and a propensity score matching model after adjusting for pre-operative, intra-operative, and hospital-related confounders. RESULTS: A total of 181 patients from 17 hospitals were included, of whom 107 (59.1%) were treated using the planned relaparotomy strategy. The multivariate mixed effects regression model indicated no significant differences for in-hospital mortality (61 patients [57.0%] in the planned relaparotomy group vs. 28 patients [37.8%] in the on-demand relaparotomy group; adjusted odds ratio [95% confidence interval] = 1.94 [0.78-4.80]), as well as in 28-day mortality, adverse events, and ICU-free days. Significant reduction in ventilator-free days was observed in the planned relaparotomy group. Propensity score matching analysis of 61 matched pairs with comparable patient severity did not show superiority of the planned relaparotomy strategy. CONCLUSIONS: The planned relaparotomy strategy, compared with on-demand relaparotomy strategy, did not show clinical benefits after the initial surgery of patients with NOMI. Further studies estimating potential subpopulations who may benefit from this strategy are required.