Evaluation of the biological tolerability of the starch-based medical device 4DryField® PH in vitro and in vivo a rat model.

To evaluate in vitro cytotoxicity/biocompatibility as well as in vivo tolerability of the novel polysaccharide 4DryField® PH, certified for haemostasis and adhesion prevention. In vitro cytotoxicity/viability testing according to ISO EN 10,993 using murine and human tumour cell lines incubated with 4DryField® PH (PlantTec Medical GmbH). Using a rat model the impact of 4DryField® PH on animals viability and in vivo effects were macro- and micropathologically assessed. In vitro testing revealed no cytotoxic effect of 4DryField® PH nor enhancement of viability to tumour cell lines. In vivo viability of rats was unimpaired by 4DryField® PH. Bodyweight loss in animals with abdominal injury plus treatment with 4DryField® PH was in the range of controls and less than in injured rats without treatment. At day 7 after surgery no formation of adhesions, neither macroscopic nor histological remnants nor signs of foreign body reaction were present in animals without injury. In animals with peritoneal injury and 4DryField® PH application, histopathological observation revealed minor residuals of polysaccharide in the depth of wound cavity embedded in a thickened subperitoneal layer; however, with a suggested intact neoperitoneum. The presence of mononuclear cells surrounding polysaccharide particles in varying states of degradation was observable as well. 4DryField® PH is not cytotoxic and does not enhance viability of tumour cell lines. High dose of 4DryField® PH of 1.09 g/kg bodyweight is well tolerated and reduces weight loss in animals with peritoneal injury. The biocompatibility of 4DryField® PH can be rated as being excellent.

Poehnert D ，Abbas M ，Maegel L ，Sambale F ，Lavrentieva A ，Kreipe HH ，Klempnauer J ，Winny M ... -  《-》

Comparison of adhesion prevention capabilities of the modified starch powder-based medical devices 4DryField(®) PH and Arista™ AH in the Optimized Peritoneal Adhesion Model.

Adhesion barriers can be based on numerous substances. In the rat Optimized Peritoneal Adhesion Model (OPAM) the starch-based hemostats 4DryField and Arista were tested for their capability to act in a preventive manner against adhesion formation (applied as a powder that was mixed in situ with saline solution to form a barrier gel). Adhesions were scored using the established scoring systems by Lauder and Hoffmann, as well as histopathologically using the score by Zühlke. Animals receiving saline solution were used as controls. As previously published, 4DryField reduced peritoneal adhesions significantly. However, Arista did not lead to a statistically significant reduction of adhesion formation. When comparing 4DryField and Arista applied in the same manner, only 4DryField was significantly effective in preventing peritoneal adhesions. Histopathological evaluations confirmed the results of the macroscopic investigation, leading to the conclusion that starch-based hemostats do not generally have the capability to function as effective adhesion prevention devices.

Poehnert D ，Neubert L ，Klempnauer J ，Borchert P ，Jonigk D ，Winny M ... -  《International Journal of Medical Sciences》

Evaluation of 4DryField® PH as Adhesion Prevention Barrier Tested in an Optimized Adhesion Model in Rats.

Adhesions due to pelvic/abdominal surgery are a common serious pathology possibly entailing severe complications. This study investigates the adhesion prevention capability of the novel starch-based agent 4DryField® PH, which together with saline solution forms a barrier gel. Herein, an optimized adhesion model (OPAM) inducing severe adhesions/agglutinations with high reproducibility was used. In 19 Lewis rats, a 1 × 2 cm abdominal wall defect was created, the peritoneum of the neighboring cecum was abraded, and both injured areas were approximated by suture. Rats were randomized to control (n = 10) or 4DryField PH treatment (n = 9) groups. Another 8 rats had sham surgery for safety assessment of 4DryField PH. At day 7, the quantity and quality of adhesions were assessed macro-/microscopically and evaluated statistically. 4DryField PH treatment significantly reduced the incidence and severity of adhesions as verified by significantly improved adhesion scorings (0.4 vs. 4.5; 1.1 vs. 9). Histology revealed reconstitution of the cecum and abdominal wall including regeneration of the visceral/parietal peritoneum. In sham-operated rats, 4DryField PH did not induce adhesion formation. 4DryField PH gel was highly effective in preventing adhesions. Histologically, the injured cecum and abdominal wall regenerated well in the presence of 4DryField PH. Considering the severity of OPAM trauma, the potential of 4DryField PH to prevent adhesions can be rated excellent.

Poehnert D ，Abbas M ，Kreipe HH ，Klempnauer J ，Winny M ... -  《-》

Comparison of adhesion prevention capabilities of the modified starch powder-based medical devices 4DryField(®) PH, HaemoCer™ PLUS and StarSil(®) in the Optimized Peritoneal Adhesion Model.

Poehnert D ，Neubert L ，Winny M 《International Journal of Medical Sciences》

Evaluation of the Effectiveness of Peritoneal Adhesion Prevention Devices in a Rat Model.

Poehnert D ，Grethe L ，Maegel L ，Jonigk D ，Lippmann T ，Kaltenborn A ，Schrem H ，Klempnauer J ，Winny M ... -  《International Journal of Medical Sciences》