Protocol for an independent patient data meta-analysis of prophylactic mesh placement for incisional hernia prevention after abdominal aortic aneurysm surgery: a collaborative European Hernia Society project (I-PREVENT-AAA).

INTRODUCTION: Incisional hernia (IH) is a prevalent and potentially dangerous complication of abdominal surgery, especially in high-risk groups. Mesh reinforcement of the abdominal wall has been studied as a potential intervention to prevent IHs. Randomised controlled trials (RCTs) have demonstrated that prophylactic mesh reinforcement after abdominal surgery, in general, is effective and safe. In patients with abdominal aortic aneurysm (AAA), prophylactic mesh reinforcement after open repair has not yet been recommended in official guidelines, because of relatively small sample sizes in individual trials. Furthermore, the identification of subgroups that benefit most from prophylactic mesh placement requires larger patient numbers. Our primary aim is to evaluate the efficacy and effectiveness of the use of a prophylactic mesh after open AAA surgery to prevent IH by performing an individual patient data meta-analysis (IPDMA). Secondary aims include the evaluation of postoperative complications, pain and quality of life, and the identification of potential subgroups that benefit most from prophylactic mesh reinforcement. METHODS AND ANALYSIS: We will conduct a systematic review to identify RCTs that study prophylactic mesh placement after open AAA surgery. Cochrane Central Register of Controlled Trials, MEDLINE Ovid, Embase, Web of Science Core Collection and Google Scholar will be searched from the date of inception onwards. RCTs must directly compare primary sutured closure with mesh closure in adult patients who undergo open AAA surgery. Lead authors of eligible studies will be asked to share individual participant data (IPD). The risk of bias (ROB) for each included study will be assessed using the Cochrane ROB tool. An IPDMA will be performed to evaluate the efficacy, with the IH rate as the primary outcome. Any signs of heterogeneity will be evaluated by Forest plots. Time-to-event analyses are performed using Cox regression analysis to evaluate risk factors. ETHICS AND DISSEMINATION: No new data will be collected in this study. We will adhere to institutional, national and international regulations regarding the secure and confidential sharing of IPD, addressing ethics as indicated. We will disseminate findings via international conferences, open-source publications in peer-reviewed journals and summaries posted online. PROSPERO REGISTRATION NUMBER: CRD42022347881.

Safety and efficacy of kidney transplantation in patients with aortoiliac stenosis: a retrospective cohort study.

BACKGROUND: The impact of aortoiliac occlusive disease on kidney transplantation remains unclear. This study aims to investigate the clinical outcomes of kidney transplant patients with aortoiliac atherosclerotic stenosis. METHODS: Retrospective data from our transplant center were used to identify patients undergoing kidney transplantation between January 2010 and December 2020. Aortoiliac atherosclerotic stenosis was screened and stratified by the Trans-Atlantic Inter-Society Consensus (TASC) II classification. The primary outcome was patient survival. Secondary outcomes were 90-day mortality, death-censored graft survival, graft function, and arterial complications. Propensity score matching was used to match all patients in the stenosis group with patients without stenosis sharing similar characteristics. RESULTS: The analysis included 655 patients, 524 without stenosis and 131 with aortoiliac stenosis (95 with TASC A/B stenosis and 36 with TASC C/D stenosis). Recipient age [median (IQR), 66 (60-70) vs. 66 (59-71) years; P =0.47], sex [male: 87 (66%) vs. 355 (68%), P =0.85], and comorbidities were comparable between the stenosis and no-stenosis groups. Forty-six (35%) patients with stenosis were symptomatic. Patient survival was significantly lower in the stenosis group compared with the no-stenosis group (TASC A/B: 30.6% vs. no-stenosis: 44.1%, P =0.013; TASC C/D: 11.4% vs. no-stenosis: 44.1%, P <0.001). The incidence rates of artery dissection, lower extremity ischemia, and acute thrombosis were significantly higher in the stenosis group ( P <0.001). However, death-censored graft survival (TASC A/B: 73.6% vs. no-stenosis: 72.9%, P =0.62; TASC C/D: 58.1% vs. no-stenosis: 72.9%, P =0.16) and graft function were comparable between the groups. CONCLUSIONS: Aortoiliac atherosclerotic stenosis significantly impacts patient survival but not graft survival. Our analyses suggest that patients with TASC A/B stenosis have prolonged survival and enhanced quality of life through kidney transplantation. However, for patients with TASC C/D stenosis, kidney transplantation improves quality of life without bringing survival benefits.

The incidence of extraction site incisional hernia after minimally invasive colorectal surgery: a systematic review and meta-analysis.

AIM: Minimally invasive colorectal surgery reduces surgical trauma with better preservation of abdominal wall integrity, but the extraction site is still at risk of incisional hernia (IH). The aim of this study was to determine pooled incidence of IH for each type of extraction site and to compare rates of IH after midline, nonmidline and Pfannenstiel extraction. METHOD: A systematic review and meta-analysis was conducted using the PRISMA guidelines. Single-armed and multiple-armed cohort studies and randomized controlled trials regarding minimally invasive colorectal surgery were searched from five databases. Outcomes were pooled and compared with random-effects, inverse-variance models. Risk of bias within the studies was assessed using the Cochrane ROBINS-I and RoB 2 tool. RESULTS: Thirty six studies were included, with a total 11,788 patients. The pooled extraction site IH rate was 16.0% for midline (n = 4081), 9.3% for umbilical (n = 2425), 5.2% for transverse (n = 3213), 9.4% for paramedian (n = 134) and 2.1% for Pfannenstiel (n = 1449). Nonmidline extraction (transverse and paramedian) showed significantly lower odds ratios (ORs) for IH when compared with midline extraction (including umbilical). Pfannenstiel extraction resulted in a significantly lower OR for IH compared with midline [OR 0.12 (0.50-0.30)], transverse [OR 0.25 (0.13-0.50)] and umbilical (OR 0.072 [0.033-0.16]) extraction sites. The risks of surgical site infection, seroma/haematoma or wound dehiscence were not significantly different in any of the analyses. CONCLUSION: Pfannenstiel extraction is the preferred method in minimally invasive colorectal surgery. In cases where Pfannenstiel extraction is not possible, surgeons should avoid specimen extraction in the midline.

Medialization after combined anterior and posterior component separation in giant incisional hernia surgery, an anatomical study.

BACKGROUND: To obtain tension-free closure for giant incisional hernia repair, anterior or posterior component separation is often performed. In patients with an extreme diameter hernia, anterior component separation and posterior component separation may be combined. The aim of this study was to assess the additional medialization after simultaneous anterior component separation and posterior component separation. METHODS: Fresh-frozen post mortem human specimens were used. Both sides of the abdominal wall were subjected to retro-rectus dissection (Rives-Stoppa), anterior component separation and posterior component separation, the order in which the component separation techniques were performed was reversed for the contralateral side. Medialization was measured at 3 reference points. RESULTS: Anterior component separation provided most medialization for the anterior rectus sheath, posterior component separation provided most medialization for the posterior rectus sheath. After combined component separation techniques total median medialization ranged between 5.8 and 9.2 cm for the anterior rectus sheath, and between 10.1 and 14.2 cm for the posterior rectus sheath (depending on the level on the abdomen). For the anterior rectus sheath, additional posterior component separation after anterior component separation provided 15% to 16%, and additional anterior component separation after posterior component separation provided 32% to 38% of the total medialization after combined component separation techniques. For the posterior rectus sheath, additional posterior component separation after anterior component separation provided 50% to 59%, and additional anterior component separation after posterior component separation provided 11% to 17% of the total medialization after combined component separation techniques. Retro-rectus dissection alone contributed up to 41% of maximum obtainable medialization. CONCLUSION: Anterior component separation provided most medialization of the anterior rectus sheath and posterior component separation provided most medialization of the posterior rectus sheath. Combined component separation techniques provide marginal additional medialization, clinical use of this technique should be carefully balanced against additional risks.