Development and evaluation of an absorbable and highly elastic thread to optimize the suture quality of complex intestinal anastomosis ("E-Suture 2.0")

• Applicants: Professor Dr.-Ing. Thomas Gries; Professor Dr. Andreas Lambertz
• Subject Area: General and Visceral Surgery ; Biomaterials
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 386716105

After a visceral surgical resection, intestinal continuity is in many cases restored by a manual suture (anastomosis). A postoperative leak - the so-called anastomotic leakage - is a complication that is highly relevant for patients and the healthcare system. It leads to the escape of intestinal secretions into the abdominal cavity with subsequent inflammation of the peritoneum (peritonitis), creating a life-threatening situation for the affected patient. One of the main causes of anastomotic leakage is tissue destruction (“comet tail defect”), which is caused by cutting of the suture into the tissue. Therefore, in order to avoid anastomotic leakage, a reduction of suture tension to a non-pathological level without corresponding tissue destruction is of decisive importance.As part of an initial project funded by the DFG, we hypothesized that the suture quality of an intestinal anastomosis can be positively influenced by changing suture geometry as well as suture elasticity. Elastic and surface-modified threads were developed and evaluated in vitro and in animal models in vivo. In summary, the thread elasticity could be identified as a positive influencing factor, an influence of the change in thread geometry was not observed. Now, we present a follow-up project that continues the successfully completed project in several areas:While the production of non-resorbable, elastic threads from thermoplastic polyurethanes (TPU) was initially investigated due to the lower technical textile complexity, resorbable, elastic threads are now to be made from resorbable TPU, since the threads used in everyday clinical practice are made of poly-p-dioxanone ( PDS) are also absorbable. Accordingly, a PDS thread is now used as control group and not a polyvinylidene fluoride thread (PVDF) as in the previous project. Furthermore, while small intestinal anastomosis were sutured as "standard anastomosis" with the new threads initially to demonstrate the feasibility in a large animal model, anastomosis of the pancreas and thus complex intestinal anastomosis known as "problem anastomosis” are to be addressed now.Based on the promising results of the completed project, the follow-up project presented here represents a logical further development. Both the textile-technical properties of the threads and the in vivo evaluation in the animal model become significantly more complex and closer to reality.

• DFG Programme: Research Grants