OBJECTIVE: To identify predictors of failed enema reduction in children with intussusception. METHODS: PubMed and EMBASE were searched for all studies published over a 20-year time frame, prior to March 25, 2020. Original articles that reported predictors of failed enema reduction were included. The pooled odds ratio (OR) for successful enema reduction according to various features was calculated. The combined estimates were meta-analytically pooled by random-effects modeling. The risk of bias was assessed using the National Institute of Health Quality Assessment Tool. This review was registered to the PROSPERO (CRD42020190178). RESULTS: A total of 38 studies, comprising 40,133 cases, were included. The shorter duration of symptoms (< 24 h; combined OR, 3.812; 95% CI, 2.150-6.759) and abdominal pain (combined OR, 2.098; 95% CI, 1.405-3.133) were associated with the success (all p < 0.001). Age < 1 year (combined OR, 0.385; 95% CI, 0.166-0.893; p = 0.026), fever (combined OR, 0.519; 95% CI, 0.371-0.725; p < 0.001), rectal bleeding (combined OR, 0.252; 95% CI, 0.165-0.387; p < 0.001), and vomiting (combined OR, 0.497; 95% CI, 0.372-0.664; p < 0.001) were associated with the failed reduction. The ascites (combined OR, 0.127; 95% CI, 0.044-0.368; p = 0.001), left-sided intussusception (combined OR, 0.121; 95% CI, 0.058-0.252; p < 0.001), and trapped fluid (combined OR, 0.179; 95% CI, 0.061-0.525; p = 0.017) on US were associated with the failed reduction. CONCLUSIONS: Successful predictors for intussusception reduction have been summarized. This evidence can help identify patients who are more likely to fail non-operative reduction and could be potential surgical candidates. KEY POINTS: â¢ A shorter duration of symptoms and presence of abdominal pain were associated with increased probability of success. â¢ Age (less than 1 year), presence of fever, rectal bleeding, vomiting, and presence of ascites, left-sided intussusception, or trapped fluid on ultrasonography were associated with decreased probability of success. â¢ This study suggests that various clinical and ultrasonography predictors would help identify patients who are more likely to fail nonoperative reduction and identify potential preoperative candidates.
Predictors of failed enema reduction in children with intussusception: a systematic review and meta-analysis