Update Systematic Review, Meta-Analysis and GRADE Assessment of the Evidence on Parastomal Hernia Prevention-A EHS,...

Objective: To perform a systematic review and meta-analysis on the effectiveness of prophylactic mesh for the prevention of parastomal hernia in end colostomy, with the ultimate objective to summarize the evidence for an interdisciplinary, European rapid guideline. Methods: We updated a previous systematic review with de novo evidence search of PubMed from inception up to June 2022. Primary outcome was quality of life (QoL). Secondary outcomes were clinical diagnosis of parastomal hernia, surgery for parastomal hernia, and 30 day or in-hospital complications Clavien-Dindo ≥3. We utilised the revised Cochrane Tool for randomised trials (RoB 2 tool) for risk of bias assessment in the included studies. Minimally important differences were set a priori through voting of the panel members. We appraised the evidence using GRADE and we developed GRADE evidence tables. Results: We included 12 randomized trials. Meta-analysis suggested no difference in QoL between prophylactic mesh and no mesh for primary stoma construction (SMD = 0.03, 95% CI [-0.14 to 0.2], I² = 0%, low certainty of evidence). With regard to parastomal hernia, the use of prophylactic synthetic mesh resulted in a significant risk reduction of the incidence of the event, according to data from all available randomized trials, irrespective of the follow-up period (OR = 0.33, 95% CI [0.18-0.62], I² = 74%, moderate certainty of evidence). Sensitivity analyses according to follow-up period were in line with the primary analysis. Little to no difference in surgery for parastomal hernia was encountered after pooled analysis of 10 randomised trials (OR = 0.52, 95% CI [0.25-1.09], I² = 14%). Finally, no significant difference was found in Clavien-Dindo grade 3 and 4 adverse events after surgery with or without the use of a prophylactic mesh (OR = 0.77, 95% CI [0.45-1.30], I² = 0%, low certainty of evidence). Conclusion: Prophylactic synthetic mesh placement at the time of permanent end colostomy construction is likely associated with a reduced risk for parastomal hernia and may confer similar risk of peri-operative major morbidity compared to no mesh placement. There may be no difference in quality of life and surgical repair of parastomal hernia with the use of either approach.