P-OGC90 Hiatus Hernia post oesophagectomy for oesophageal cancer: incidence & outcomes

Background The development of a hiatus hernia following oesophagectomy is a well-documented occurrence. The aim of this study is to examine the incidence of hiatus hernia formation, the symptoms patient present with and differences between open and laparoscopic/minimally invasive surgery. Methods A dataset containing data on all patients from an upper GI regional tertiary referral centre were analysed. All subsequent patients who underwent oesophagectomy between Nov 2014 and Nov 2020 were included. Results A total of 268 patients underwent oesophagectomy over this time, of whom 81.0% (n = 217/268) were male and the median age was 68 years old (62-73 years). The median BMI at the time of operation was 27.6Kg/m2 (IQR 24.6-30.7Kg/m2). Over a median follow up of 12 months (IQR 5-21), 4.5% (n = 12/268) developed a hiatus hernia. Amongst these 12, the most common organ in the hernia was the transverse colon (66.7%, n = 8/12) and the small bowel (n = 3). The most reported symptoms in those with a hiatus hernia were respiratory symptoms (cough/breathlessness: n = 5), reflux (n = 3), vomiting (n = 3) and chest pain (n = 3). There was no correlation between BMI and the occurrence of a hiatus hernia (p = 0.145) nor were there differences across males and females in terms of hiatus hernia rates (p = 0.845). In patients who had prophylactic repair of the diaphragm (n = 126/268, 47.0%) the rate of hernia repair was no different (4.8%) compared with those who did not have a prophylactic diaphragmatic repair with sutures (4.2%, p = 0.832). There was however a correlation between the volume of intraoperative blood loss and the occurrence of a hiatus hernia, with increasing blood loss correlating with a higher likelihood of hernia occurrence (r = 0.295, p = 0.037). Conclusions Hiatus hernia is a relatively common occurrence after oesophageal cancer surgery, with most patients suffering from chest symptoms, pain, and reflux. Intra-operative blood loss may influence the chances of developing a hiatus hernia. Prophylactic measures such as reinforcing the diaphragm or hiatus with sutures, do not appear to affect hernia rates.

O46 SUTURABLE MESH IMPROVES OUTCOMES FOR LAPAROTOMY CLOSURE IN COMPARISON TO POLYPROPYLENE SUTURE IN A REALISTIC PORCINE MODEL

Aim Laparotomy closures fail due to suture pull-through. We hypothesize that a novel suturable mesh device may limit pull-through via mechanisms of force distribution at the suture-tissue interface and fibrous encapsulation of the device filaments. This new tissue approximation device may lead to improved outcomes for laparotomy closure. Material and Methods Fifteen domestic swine 74 kg in size were randomly allocated to three groups for epigastric laparotomy closure with either size 0 suturable mesh, number 1 suturable mesh, or number 1 polypropylene. All three devices were placed in running fashion with 1 cm bites and 1 cm travels. Primary endpoints were hernia formation at 13 weeks and a semiquantitative analysis of the histological tissue response. Secondary endpoints included adhesions, surgical site occurrence (SSO), and documentation of “loose sutures”. Results There were numerically fewer hernias in the number 1 suturable mesh group. Nine of the 10 suturable mesh devices were well encapsulated within the tissues and could not be pulled away, while 4 of the 5 polypropylene sutures were loose. Adhesions were least for number 1 suturable mesh. Histologically, the suturable mesh implanted devices showed good fibrovascular ingrowth and were judged to be “non-irritants”. The soft tissue response was statistically greater (p = .006) for the number 1 suturable mesh than for the number 1 polypropylene. Conclusions The mechanism of how meshes support closure sites is clearly demonstrated with this model. Suturable mesh has the potential to change surgical algorithms for abdominal wall closure.

P047 SUTURE-TOOL: A SUTURING DEICE FOR SWIFT AND STANDARDIZED ABDOMINAL APONEUROSIS CLOSURE

Aim Introduction Surgeons can reduce incisional hernia formation by adhering to standardized techniques for incisional wound closure. This is often neglected by the time a long operation is to be ended and can lead to the risk of developing an incisional hernia or a wound rupture. To address this issue, a suturing machine (Suture-TOOL) was developed for swift and standardized abdominal closure. The aim was to compare the user safety, speed, and suturing quality between Suture-TOOL and manual Needle-Driver suturing. Material and Methods Fifteen surgeons who were specialists in surgery, urology, and gynaecology as well as surgical trainees were invited. The Suture-TOOL was presented to the surgeons who read the instructions for use before starting the test. Each surgeon closed nine 15-cm-long incisions in a human body model; six with Suture-TOOL and three with the Needle-Driver technique. Gloves were examined for puncture damage. Endpoints were suture-length/wound-length (SL/WL)-ratio, closure time, number of stitches, learning curve, and glove puncture rate. A VAS-evaluation concerning different Suture-TOOL user impressions was completed. Results SL/WL-ratio ≥4 was 98% for Suture-TOOL versus 69% for Needle-Driver (p < 0,001). Suture time was shorter for Suture-TOOL (p = 0,013). The median SL/WL-ratio was similar between the groups. The learning curve plateaued after three closures using Suture-TOOL. Two glove punctures were detected—all in the Needle-Driver group. Suture-TOOL received high VAS scores for all measured functionalities. Conclusions Suture-TOOL is a promising device for clinical use. It is safe, easy, and fast resulting in a high-quality suture lines with a short learning curve and a high functionality ranking.

O38 PROPHYLACTIC LIQUID MESH - A SMALL ANIMAL EXPERIMENT

Aim Background: Surgical mesh is widely used not only to treat but also to prevent incisional hernia formation. Despite much effort by material engineers, the ‘ideal' mesh mechanically, biologically and surgically easy to use remains elusive. Advances in tissue engineering and nanomedicine have allowed new concepts to be tested with promising results in both small and large animals. Abandoning the concept of a pre-formed mesh completely for a ‘pour in liquid mesh’ has never been tested before. Material and Methods Thirty rabbits underwent midline laparotomy with closure using an absorbable suture and small stitch small bites technique. In addition, their abdominal wall closure was reinforced by a liquid nanofibrous scaffold composed of a fibrin sealant and nanofibers of poly-ε-caprolactone with or without hyaluronic acid or the sealant alone, placed as an ‘onlay’ over the closed abdominal wall. The animals were sacrificed at 6 weeks and their abdominal wall was subjected to histological and biomechanical evaluations. Results All the animals survived the study period with no major complication. Histological evaluation showed an eosinophilic infiltration in all groups and foreign body reaction more pronounced in the groups with nanofibers. Biomechanical testing demonstrated that groups treated with nanofibers developed a scar with higher tensile ultimate and yield strength. Conclusions The use of nanofibers in a liquid form applied to the closed abdominal wall is easy to use and improves the biomechanical properties of healing fascia at 6 weeks after midline laparotomy in a rabbit model.

Hernia formation after single-stage umbilical vein marsupialization in three foals diagnosed with omphalophlebitis.

Omphalophlebitis in foals is treated with complete resection of the affected umbilical remnants. When total resection cannot be accomplished, umbilical vein marsupialization can be implemented with minimally reported complications. This case series highlights hernia formation as a potential complication following one-stage umbilical vein marsupialization.

Cystic adventitial disease of the popliteal artery and ILIAC vein

These two cases of successful treatment of a rare vascular disorder – cystic adventitial disease (CAD). Case 1: CAD of the popliteal artery with narrowing of the popliteal artery and intermittent claudication. Case 2: CAD of iliac vein with irreducible femoral hernia formation and iliac vein subocclusion. We described preoperative planning, surgical intervention and postoperative management in our cases. Surgery after careful preoperative planning is only one effective method of treatment of CAD and has good long-term results.

On the features of the preperitoneal space multifascial structure in clinical and anatomical issues

AIM: to determine the prospects for the preventive endoprosthetics of the abdominal wall at preventing the development of postoperative ventral hernias. MATERIALS AND METHODS: A meta-analysis of the literature data performed to determine the effectiveness of preventive endoprosthetics for the prevention of ventral hernia formation. Topographical study has been conducted to explore the most promising levels of the mesh location. RESULTS: During the meta-analysis it has been found that performing preventive endoprosthesis of the anterior abdominal wall t in the preperitoneal space reduces the frequency of ventral hernias. There were no significant differences in the frequency of infectious complications and serom in the experimental and control groups according to studied publications. During the preparation it has been distinguished that between the transverse fascia and the peritoneum there is a preperitoneal fascia consisting of two leaves, which is most manifest in the lateral parts. In the umbilical region above linea arcuata the preperitoneal fascia is thinned and represented by separate fibers that are difficult to differentiate as a structure between the transverse fascia and the peritoneum. In the lateral parts of the abdominal wall, the preperitoneal fascia is well expressed. It has been distinguished that the retroperitoneal fascia, formed by the junction of two sheets of the Gerot fascia continues into the fascia between the transverse fascia and the peritoneum. CONCLUSION: Preventive endoprosthesis of the anterior abdominal wall is an effective and safe method of preventing the formation of postoperative ventral hernias. The anterior abdominal wall is characterized by a complex multifascial structure, which is of fundamental importance for various types of surgery. Between the transverse fascia and the peritoneum there is preperitoneal fascia which is represented by two leaflets. Its continuation is the retroperitoneal fascia (5 figures, 2 tables, bibliography: 8 refs).

Inhibition of Estrogen Signaling Reverses Established Inguinal Hernias

Background: An inguinal hernia occurs when an intestinal loop or fat pushes through a weak spot in the lower abdominal muscle (LAM), causing a painful bulge that has the potential to cause bowel obstruction. Despite a high prevalence in men (~25%), non-surgical approaches are not available to treat this disease. We recently found a critical role of estrogen and estrogen receptor alpha (ERα) in inguinal hernia formation. To examine this further, we use a humanized aromatase mouse model (Aromhum) where all of the male mice develop scrotal hernias as a pre-clinical model to test the first pharmacological intervention for inguinal hernias. These mice are utilized because their skeletal muscle tissue contains aromatase and produces estradiol (E2), which acts via ERα in the LAM stromal fibroblasts and leads to fibrosis and muscle atrophy. Hypothesis: E2-ERα modulation can inhibit and reverse the formation of inguinal hernias in Aromhum mice by reducing LAM fibrosis and atrophy. Results: We tested three types of treatments to inhibit E2-ERα signaling: letrozole, fulvestrant, and raloxifene. Letrozole, an aromatase inhibitor, was shown to inhibit hernia formation and reversed small (150-175 mm2) scrotal hernias (n = 10-15/group, p<0.0001). The LAM tissues also showed a reduction in fibrosis (n = 5-8/group, p = 0.0004) and a concurrent increase in myofiber cross-sectional area (n = 5-8, p=0.0356) compared to placebo-treated mice. Similarly, fulvestrant and raloxifene, E2-ERα antagonists, also inhibited hernia formation (n = 10-15/group). Most interestingly, both drugs reversed large and severe hernias (>200 mm2, n = 10-15/group), accompanied by a decrease in muscle fibrosis and increase in myofiber cross-sectional area (ongoing study, n = 10-11, p<0.0001) compared to placebo mice. The drug-treated mice had lower expression of pro-fibrotic genes such as Mmp3, Emb, Spon2, Timp1, and Tgfb1 in the LAM tissues compared to placebo-treated LAM. Furthermore, we analyzed the differences in extracellular matrix producing genes and muscle regeneration markers between the placebo and drug-treated muscle tissues. Conclusion: We find that inhibition of the E2-ERα signaling pathway can reverse mild or severe inguinal hernias. Successful treatment is accompanied by decreased skeletal muscle fibrosis and reversal of myocyte atrophy. These interventions are promising non-surgical treatment options for patients suffering from severe and recurrent inguinal hernias.

MO701COMBINED PROCEDURE OF PRE- EXISTING ABDOMINAL WALL HERNIA REPAIR AND PERITONEAL CATHETER INSERTION. LONG TERM FOLLOW- UP IN PERITONEAL DIALYSIS TREATMENT

Background and Aims Successful peritoneal dialysis (PD) program requires a combination of optimal peritoneal access and low incidence of complications. Between pitfalls of this modality are early mechanical complications such as leak, malfunction, and new abdominal wall hernia formation in the long term of PD treatment. Pre-existing abdominal wall hernia is a relative contraindication for PD. Hernias are also a known and not uncommon complication over the course of PD and one of the causes of technique failure. In our center, a physical examination and an ultrasound for hernias detection are routine procedures before the start of PD. If a hernia is discovered, combined hernia repair and catheter implantation are performed. The aim of this study was to assess to long- term results of this approach. Method The current study presents the retrospective analysis of 10 years' experience of our PD program (1.01.2009 – 31.12. 2018) including all incident PD patients who underwent their first peritoneal catheter placement procedure during the study period. The primary endpoints of the study were the rate of hernia formation in the course of PD treatment, type of hernias, identification risk factors for hernia formation and rate of hernia recurrence after previous repair. The secondary endpoint was the rate of procedure-related complications: infectious, leaks and primary catheter malfunction in patients who underwent surgical catheter insertion compared to percutaneous technique. Patients were followed until the end of PD treatment or until 31.10.2019. Results A total of 211 patients were included in the analysis. Of these, 24.5% underwent surgical procedures and 75.5% percutaneous insertion. Mean follow-up was 23.3 ± 25 months (2 to 96 months). About half (53.1%) of the patients were diabetic, aged 64.2±13 years. In 32 patients (15%) a preventive hernia repair with a simultaneous catheter implantation were performed. Patients who underwent a preventive hernia repair were significantly older than other patients (69.4±11.1 years versus 63.2±13.1 years, P=0.013). During the study period, 203 of 211 patients were treated by PD. Thirty three (16.1%) have developed 38 new hernias. Patients suffering from a new hernia during PD were predominantly male, with longer dialysis vintage than patients without new hernia formation (35.3±22.8 months versus 23±22.9, respectively. P=0.001). Five of 33 patients suffered multiple hernias, including recurrent hernias at the same site. Most common types were inguinal and umbilical (44.7% each other), while only few were incisional or ventral. None of our patients suffered from a pericatheter one. The overall rate of new hernias development was 0.09/patient/years. Neither age, comorbidities, obesity nor polycystic kidney disease did not increase the rate of hernia formation during the course of PD treatment. There was no significant association between type of catheter insertion procedure (surgical/percutaneous) and infections, leakages or catheter function. Leak incidence in diabetic patients was significantly higher in comparison with nondiabetic patients (8% versus 1%, P=0.021). Infectious complications were not different between diabetic and not diabetics patients (5.4% among diabetic patients versus 2% nondiabetic, P=0.29). Conclusion Our findings show that male gender and prolonged peritoneal dialysis duration are the main risk factors for the appearance of hernias in the course of PD therapy. Our data also confirm previous observations that the placement of PD catheter using a paramedian incision approach significantly reduces the incidences of exit site and incision hernias. We suggest that early diagnosis of latent asymptomatic hernias and hernia repair prior to starting PD can improve technique survival.