Tissue repair in neonatal and pediatric surgery: analysis on infections in surgically implanted natural biomaterials.

INTRODUCTION: Over the past 4 decades commercially available natural and synthetic biomaterials have been employed for various reconstructive procedures in the pediatric population. The aim of this study was to identify the types of commercially available natural biomaterials and their areas of application in the pediatric age group. Furthermore, to perform an analysis to identify areas of application and types of biomaterials those have increased susceptibility to infections in the pediatric population. EVIDENCE ACQUISITION: The literature was reviewed from 1970-2015 using a Medline search and data concerning application of different natural biomaterials was collected. Specific search was performed regarding to infections associated with these biomaterials. EVIDENCE SYNTHESIS: The rate of major infection after implantation of the biomaterial in the group of 298 reviewed cases was 5%. Patients with acute burn wounds which were treated with biomaterials presented the group with higher infection rates of 5-33%. CONCLUSIONS: The demand for these biomaterials has exponentially increased due to the worldwide rise in interest in tissue engineering research. Even using the appropriate techniques of implantation and professional postoperative care biomaterial associated infections cannot be eliminated. However, the current rate of infections is not a limiting factor for using the biomaterials in pediatric surgery.

Cosmetic Outcomes of Sutureless Closure in Gastroschisis.

Purpose A sutureless gastroschisis repair allows for spontaneous closure of abdominal wall defect. We report our experience focusing on final esthetic outcome. Methods Retrospective data were collected from medical reports of all neonates with gastroschisis operated from January 2009 to December 2013. Variables recorded included patients descriptors, management modality, and cosmetic outcome. Results From the overall group of 38 patients with gastroschisis, 20 infants treated with sutureless closure were included in this study. In the analyzed cohort, 17 (85%) children were operated under general anesthesia and 3 (15%) without intubation. Primary reduction was possible in 15 (75%) cases, and in 5 (25%) we used silo. There were two (10%) deaths in late postoperative course due to septic complications. Three (15%) infants needed laparotomy because of adhesions and bowel obstruction. There were no infectious complications of the wound. Only 55% (10/18) of children presented umbilical hernia prior to discharge. Only two (11%) children with umbilical hernia were operated until now. Almost all patients (16/18; 89%) present excellent final cosmetic result without scar formation. Conclusion Sutureless closure of uncomplicated gastroschisis is a safe technique that reduces need of intubation and provides excellent cosmetic results.

Laparoscopic and Laparoscopy-Assisted Resection of Enteric Duplication Cysts in Children.

INTRODUCTION: Enteric duplication (ED) cysts are rare. The commonness of ultrasonographic investigation contributes to an earlier diagnosis of such a pathology before the onset of the first clinical symptoms. A planned mini-invasive surgical treatment during the infancy is proposed. This study presents the possibility and safety of elective laparoscopic or laparoscopy-assisted mini-invasive resection of ileal (IL) and ileocecal (IC) duplications, thus avoiding bowel resection. MATERIALS AND METHODS: A retrospective review was conducted of medical records of 6 patients at the age from 3 to 22 months with the diagnosis of ED, treated in the Department of Pediatric Surgery, Jagiellonian University Medical College, Krakow, Poland, within the period from January 2012 to September 2014. RESULTS: Excision of cysts without bowel resection was performed in five children with IC and IL duplications. Laparoscopic excision was performed in two children with IC duplication; in the other three children (1 IC and 2 IL duplication), laparoscopy confirmed the diagnosis with consecutive cyst excision without bowel resection after external evacuation of the cyst. The external resection of the cecum and Bauhin's valve was necessary in 1 patient with large IC duplication and malrotation. The postoperative course was satisfactory in all the cases. CONCLUSIONS: The laparoscopic approach allows for confirming the diagnosis and accurately defining the exact site of duplication, as well as for effective and safe mini-invasive treatment. Laparoscopic or laparoscopy-assisted excision of ED without bowel resection is a safe option in a significant number of IL and IC duplications.

Comparison of suturing techniques in the formation of collagen scaffold tubes for composite tubular organ tissue engineering.

In order to construct tubes for tissue engineering of composite tubular organs in the gastrointestinal tract, suturing techniques were investigated with regards to (a) type of suture material, (b) state of scaffold, (c) technical variations and (d) changes in scaffold morphology. Collagen scaffolds of 13 mm diameter and 3 mm thickness, in both dry and wet states, were sutured using braided and monofilament sutures. Four suture techniques were employed (a) continuous loop, (b) interrupted loops, (c) interrupted edge sutures and (d) continuous running edge suture. Scanning electron microscopic imaging was performed on the 4 tubes sutured. Monofilament sutures were used for tube formation as braided sutures were unsuitable. Dry scaffolds demonstrated tears during knot tying and fractures when bent around a stent. The interrupted and continuous running edge suture were the most suitable suturing techniques in wet scaffolds; further confirmed by scanning electron microscopy imaging. Our approach to tissue engineer segments of the gastrointestinal tract involves cell-seeding on scaffolds to permit attachment in vitro and later wrapping of scaffold layers of heterogeneous cells to create composite tissue. Scaffolds in wet state can be better sutured with monofilament materials using either the interrupted or running continuous edge suture technique.

Esophagus tissue engineering: in situ generation of rudimentary tubular vascularized esophageal conduit using the ovine model.

PURPOSE: Esophagus replacement using the present surgical techniques is associated with significant morbidity. Tissue engineering of the esophagus may provide the solution for esophageal loss. In our attempts to engineer the esophagus, this study aimed to investigate the feasibility of generating vascularized in situ esophageal conduits using the ovine model. METHODS: Esophageal biopsies were obtained from lambs, and ovine esophageal epithelial cells (OEEC) were proliferated. The OEEC were seeded on to bovine collagen sheets preseeded with fibroblasts. After 2 weeks of maintaining the constructs in vitro, the constructs were tubularized on stents to create a tube resembling the esophagus and implanted into the omentum for in situ tissue engineering. The edges of the omentum were sutured using nonabsorbable suture material. The implanted constructs were retrieved after 8 and 12 weeks. RESULTS: The omental wrap provided vascular growth within and around the constructs as they were integrated along the outer surface area of the scaffold. After removal of the stents, the engineered conduit revealed a structure similar to the esophagus. Histologic investigations demonstrated esophageal epithelium organization into patches on the luminal side and vascular ingrowths on the conduit's outer perimeter. CONCLUSION: Our study demonstrated the seeding of OEEC on collagen scaffolds and formation of a rudimentary conduit resembling esophageal morphology after in situ omental implantation. Vascular coverage and ingrowth in the periphery of the construct could also be demonstrated. These findings hold future promise for the engineering of the esophagus with improved microarchitecture.

Micro-computed tomography for implantation site imaging during in situ oesophagus tissue engineering in a live small animal model.

For tissue engineering of gastrointestinal organs, in situ implantation of constructs in the omentum is performed to utilize the body as a bioreactor for tissue generation. In this approach, constructs are fabricated into tubes, using stents, and implanted in the omentum to induce vascularization. In order to evaluate the constructs and its environment during the period of in situ tissue engineering in the rat model, micro-computed tomography imaging was performed. Imaging using micro-computed tomography was useful in localization of the position of the construct, evaluation of implant site tissue, degree of peripheral inflammation to neighbouring tissues and migration of the implanted construct. Images also enable the estimation of the dimensions of the construct and imaging of cyst formations or fluid accumulations on the luminal side of the tubular construct or ascites formation. Since micro-computed tomography is a non-invasive method, it can be repeated for evaluation of implanted constructs if in situ tissue engineering is performed over longer periods.