Experimental and morphological substantiation of intraperitoneal alloplasty at incisional abdominal hernias
Introduction. The treatment of incisional abdominal hernias (PAH), especially the ones of large and giant sizes, continues to be a challenge despite the introduction of modern alloplasty and laparoscopic surgery. The application of classical methods of alloplasty, including «onlay», «sublay», «inlay», combined with component separation technique (CST), is still accompanied by a relatively high incidence of local wound complications such as seroma (30.8-60.4%), suppuration (1.5-4.8%), ligature fistulas (1.2-3%) meshoma (0.06-1.6%), leading to the recurrence of hernias (10-15%). This is due to the fact that during application of such techniques, extensive dissection of tissues is performed, and a large number of blood and lymph vessels are damaged. In addition, by the «onlay» method, the mesh implant is in contact with the subcutaneous tissue. The use of intraperitoneal alloplasty with special mesh with adhesive coating reduces postoperative complications of the surgical wound. The study of morphological changes in the tissues of the abdominal wall at intraperitoneal placement of mesh implants and their comparison with classical alloplasty methods have not yet been performed.
Objective: To prove feasibility intraperitoneal placement of mesh implant during postoperative abdominal hernias.
Materials and methods. With the view to substantiate the intraperitoneal alloplasty at incisional abdominal hernias, experimental and morphological study of 80 Wistar rats has been conducted. The response of tissues in the anterior abdominal wall and internal organs at alloplasty of hernial defects has been studied in a number of ways. Depending on the alloplasty way, the animals were divided into 4 groups. In group I intraperitoneal alloplasty was performed using Parietex composite mesh with anti-adhesive coating; in group ІІ − intraperitoneal alloplasty with polypropylene mesh; in group ІІІ − placement of polypropylene mesh in the subcutaneous space over the stitched muscular-aponeurotic defect; in group IV – contact stitching of the defect without mesh implant.
Results. In the early postoperative period, 11 rats died: 2 of group I and 1 of group IV (overdose of anaesthetic medications), 6 of group II (development of peritonitis due to early peritoneal commissures because of adhesions of the intestine to the mesh which caused intestinal obstruction, necrosis of the bowel loops), 2 of group III (suppuration of surgical wound, abscess formation).
Macroscopic evaluation of the abdominal cavity at the 30th, 60ht and 120th days displayed the following results: in group I thin commissures between the edges of the mesh and internal organs are observed, the mesh is well-adhered on the part of the abdominal wall; in group II – rough commissures between the entire surface of mesh and the internal organs is observed, abdominal wall along with the mesh forms a thick inflammatory infiltrate; in group III – sporadic commissures between internal organs are observed, the mesh has partly adhered on the part of aponeurosis. In all cases, the signs of chronic inflammation were observed, in 2 cases – abscesses in the abdominal wall with rejection of the implanted mesh; in group IV – sporadic commissures in the abdominal cavity.
The results of histological studies are the most indicant in animals who were euthanized on the 120th day, due to the best adherence of the mesh with the connective tissue and the formation of mature postoperative cicatrix.
The results of the study showed that in animals of group I with intraperitoneal placement of composite mesh implant with adhesive coating, the uniform adhesion of the mesh with connective tissue was observed with minimal signs of inflammation, formation of neoperitoneum (mesh was covered with a layer of mesothelium on the part of the abdominal cavity) which prevented the mesh implant from adherence to internal organs, while the intraperitoneal placement of polypropylene mesh was accompanied by chronic inflammation, the formation of abscesses, severe coalescence of the intestine with the mesh, leading to intestinal obstruction. This fact confirms the need to use only intraperitoneal alloplasty and only special mesh with adhesive coating.
The use of intraperitoneal alloplasty as compared with the «onlay» method has a significant advantage. This is confirmed by severe inflammation of muscle-aponeurotic tissue, hypoderm and skin, wound suppuration, abscess formation, rejection of polypropylene mesh implant at its subcutaneous location.
From 2009 to 2014 in the Ukrainian center of surgical treatment of abdominal hernias 82 patients with incisional ventral hernias of gigantic sizes using intraperitoneal alloplasty underwent surgery. Patients were aged from 30 to 80. The results showed that intra-abdominal pressure in the postoperative period was at 5±2.1 mm Hg; abdominal compartment of the syndrome was not observed. Seroma was observed in 6 (7.3±2.9)% patients, suppuration of surgical wound – in 2 (2.4±1.7)%, chronic infiltrate – in 2 (2.4±1.7)%, ligature fistulas of the anterior abdominal wall – in 1 (1.2 ± 1.2)%, meshoma was not observed, inpatient periods were 7±1,2 days.
Chronic pain in the area of mesh implantation during 6-8 months after surgery was observed in 1 (1.6±1.6)% patient and it was eliminated by prescribing physical therapy and nonsteroidal anti-inflammatory drugs. Hernia recurrences were detected in 1 (1.6±1.6)% patient. These results indicate that intraperitoneal alloplasty at giant incisional hernias has significant advantages as compared to classical techniques of alloplasty.
Conclusions. The results showed that intraperitoneal placement of composite mesh coated with anti-adhesive coating reduces the incidence of local wound complications, it does not cause adhesions mesh with the internal organs and provides optimum germination connective tissue mesh implant due to its contact with the parietal peritoneum, which stimulates the active formation of neoperitoneum. It confirms the highest efficiency of intraperitoneal allohernioplasty compared to the method of placement of the implant in the grid.