Objective: Peritoneal adhesions following surgery are a common, serious pathology with severe complications. Appropriate animal adhesion models are essential for the assessment of adhesion preventing medical devices. This study introduces a variation of an established rat model in which highest degree adhesions are induced with excellent reproducibility (OPAM = optimized peritoneal adhesion model). Thus, this model seems to be eligible to study effects of adhesion preventing devices.Methods: 24 Lewis male rats were divided into four groups (OPAM, WSFX, sham-OPAM, sham-WSFX). The OPAM technique comprised cecal abrasion, creation of an abdominal wall defect plus approximation of injured areas by a suture, which was compared to a setting of lesions without suture fixation (WSFX). All rats were sacrificed at day 7. Macroscopic and histopathological evaluations were performed. Results were statistically analyzed using ANOVA and Dunnett's test.Results: In OPAM rats macroscopic analyses revealed a 90% incidence adhesion of cecum to the abdominal wall, all adhesions imposing as complete agglutination. In WSFX animals incidence of adhesions formation was 75%, while in both sham groups there were no adhesions at all. Histology showed the structure of adhesions with merged smooth muscle of colon and skeletal muscle of abdominal wall in all cases.Conclusion: OPAM technique provides adhesions of injured areas with a better probability than with conventional methods. All OPAM adhesions impressed as highest degree adhesions, i.e. agglutination. Due to high reproducibility in incidence and extend of adhesion formation, the OPAM is recommended for testing of adhesion prevention medical devices.

Background: Abdominal operations are followed by adhesions, a prevalent cause of abdominal pain, and the most frequent cause for bowel obstruction and secondary female infertility. This rat study addresses adhesion prevention capability of Adept®, Interceed®, Seprafilm®, and a novel device, 4DryField® PH which is provided as powder and generates its effect as gel.Methods: Sixty-eight male Lewis rats had cecal abrasion and creation of an equally sized abdominal wall defect, and were grouped randomly: A control group without treatment (n=10); two groups treated with 4DryField® PH using premixed gel (n=15) or in-situ gel technique (n=16); one group each was treated with Seprafilm® (n=8), Interceed® (n=9), or Adept® (n=10). Sacrifice was on day 7 to evaluate incidence, quality, and quantity of adhesions, as expressed via adhesion reduction rate (AR). Histologic specimens were evaluated. Statistical analyses used ANOVA and unpaired t-tests.Results: 4DryField® PH significantly reduced incidence and severity of adhesions both as premixed gel (AR: 85.2%) and as in-situ made gel (AR: 100%), a comparison between these two application techniques showed no differences in efficacy. Seprafilm® did not reduce incidence but severity of adhesions significantly (AR: 53.5%). With Interceed® (AR: 3.7%) and Adept® (AR: 16.1%) no significant adhesion-reduction was achieved. Except for inflammatory response with Interceed®, histopathology showed good tissue compatibility of all other devices.Conclusion: 4DryField® PH and Seprafilm® showed significant adhesion prevention capabilities. 4DryField® PH achieved the highest adhesion prevention effectiveness without restrictions concerning mode of application and compatibility and, thus, is a promising strategy to prevent abdominal adhesions.

This single-center prospective, controlled observational study investigates the impact of incisional negative pressure wound therapy on wound healing processes and its potency to prevent superficial surgical site infections (SSSI) after reversal of a double loop ileostomy. Furthermore, this study gains insight in socioeconomic aspects, like duration of hospital stay and, for the first time, patient's quality of life during the incisional negative pressure wound treatment. To address this question, an interventional group of 24 patients treated with incisional negative pressure wound therapy (Prevena incisional wound management system, KCI, Germany) and a respective control cohort of 25 patients treated with a standard sterile dressing were observed for 30 days in the postoperative course. Postoperative incisional negative pressure wound therapy resulted in statistically significant decreasing duration of hospital stay (6 days vs. 9 days, p 5 0.019) and lower rates of SSSIs (12.5% vs. 20.0%, p 5 0.478) in accordance with a not statistically significant decreased necessity of postoperative antibiotic therapy (12.5% vs. 36%, p 5 0.051). To survey subjective items of well-being and quality of life, all patients were asked to answer a questionnaire. Patients of both groups noticed increasing quality of life after reversal of their ileostomy. However, patients treated with an incisional negative pressure wound therapy had a superior improvement of a variety of subjective items, resulting in an overall much better satisfaction with the course of wound healing. Our findings suggest, that incisional negative pressure wound therapy seems to be a reasonable therapeutic option to reduce incidence of SSSIs and to have a beneficial impact to patient's quality of life, as well as, socio-economic aspects.