Meta-analysis of the Effect of Treatment Strategies for Nephrosplenic Entrapment of the Large Colon

Abstract Background A variety of treatment strategies for nephrosplenic entrapment of the large colon are reported, with conflicting evidence in published literature as to the preferred treatment option. Objectives To provide a systematic meta-analytical assessment of the efficacy of different treatment strategies in horses with confirmed or suspected nephrosplenic entrapment. Study design Meta-analysis including non-randomised studies. Methods A comprehensive literature search was performed from January 1970 to January 2017. Inclusion criteria were retrospective studies involving horses with confirmed and suspected nephrosplenic entrapment. A meta-analysis was performed using a random effects model, with the effect size calculated as an odds ratio (OR) with 95% confidence intervals (CI). Statistical significance was P Results Out of 84 peer reviewed publications that met the search criteria, 19 relevant studies were identified. Using an OR as the effect size, the meta-analysis noted that the choice of medical or surgical therapy had no statistically significant effect on survival (P=0.134). Patients treated via the rolling technique were no more likely to resolve with medical management than those treated via jogging (P=0.187). Patients treated with phenylephrine were no more likely to exhibit medical resolution than patients that did not receive phenylephrine, either when all medical treatment methods were considered (P=0.290), or when rolling under general anesthesia was used (P=0.331). Conclusions and clinical significance: Treatment strategy, including medical versus surgical therapy, does not affect the likelihood of resolution of nephrosplenic entrapment. However, the lack of randomized trials mean the results should be treated with caution and case selection remains important.