Complex abdominal wall reconstruction in the setting of contamination and active infection: a systematic review of fistula and hernia recurrence rates JD Hodgkinson, Y Maeda, CA Leo, J Warusavitarne, C Vaizey Department of Colorectal Surgery, St Mark’s Hospital, Harrow, Middlesex, United Kingdom Introduction When performing abdominal wall reconstruction (AWR), the presence of active infection, contamination or enterocutaneous fistula can greatly increase the risk of post-operative wound infection, hernia recurrence and developing fistulae. Minimal evidence is available to guide the surgeon regarding the risk of complications in this context. Aims We aim to establish the outcomes of complex AWR for VHWG grade 3 and 4 defects. Methods The analysis was conducted according to PRISMA guidelines (Figure 1). A systematic search of the MEDLINE database was performed using the MeSH search terms ‘enterocutaneous fistula’, ‘hernia’, ‘abdominal wall hernia’, abdominal wall defect’, ‘abdominal wall reconstruction’, ‘infection’ and ‘contamination’ in combination with the functions ‘AND’ and ‘OR’. Studies reporting exclusively on outcomes from single-staged repair of complex AWR in VHWG grade 3 and 4 were included. Studies including outcomes from VHWG grade 1 and 2 or from non-complex hernia repairs and studies describing the management of acute contamination (for example trauma laparotomy) were excluded. Pooled data were analysed to establish rates of fistula and hernia recurrence (Figure 2). Figure 3: A table demonstrating rates of fistula recurrence by repair method Figure 4: A table demonstrating rates of hernia recurrence by repair method Results 13 studies were included, consisting of 520 contaminated complex AWR, including 230 enterocutaneous fistula repairs. The average follow-up period was 22.3 months. Fistula recurrence was seen in 24 patients (10.4%). Suture repair alone had the lowest rate (1.7%), followed by non-biological mesh (10.3%) and biological mesh reinforcement (12%) (Figure 3). There were 129 (24.8%) reported hernia recurrences. Suture repair alone had the lowest rate (14.7%), followed by biological mesh reinforcement (25.7%) and non-biological mesh (37.9%) (Figure 4). When comparing the rate of recurrence based on fascial closure, independent of mesh use, hernias recurred significantly less frequently when fascia was closed compared to when a bridging mesh was used (16.3% (47/289) versus 40% (18/45) respectively (p=<0.001) (Fishers exact test)). Conclusion In nearly one-quarter of cases, the hernia recurred. Suture methods alone recur less often than those reinforced by mesh however this is likely a result of suture repair being used in less complex cases. Rates of recurrent fistula are comparable with reported series describing ECF repair alone, thus it is feasible to perform simultaneous ECF repair and AWR. 2B Records identified through database (n = 538) Screening Included Eligibility Identification Additional records identified through other sources (n = 2) Records after duplicates removed (n = 391) Records screened (n = 391) Records excluded (n = 259) Exclusion: Non-relevant – 150 Case report – 54 Reviews – 18 Non-English - 37   Full-text articles assessed for eligibility (n = 132) Full-text articles excluded (n = 119) Non-relevant – 87 Case report – 24 Reviews - 7 Studies included in qualitative synthesis (n = 13) Studies included in quantitative synthesis (systematic review) (n = 13) Figure 1: A PRISMA flow chart demonstrating study selection Figure 2: A table demonstrating study characteristics, patient demographics and hernia details. The Pouch Disease Activty Index {Sandborn W.J., 1994} A total score of <7 = remission A total score of >7 = active disease