Article by Diogo Teles & Roberta Lock
Repairing Gastrointestinal Defects with a Duct Tape-like Adhesive
An off-the-shelf bioadhesive patch for sutureless repair of gastrointestinal defects, Science Translational Medicine, 2022
Jingjing Wu et al., Xuanhe Zhao Lab
Gastrointestinal (GI) anastomosis (surgical connection between two channels or tubes) is performed under a wide variety of GI surgeries using sutures, staples, or sealants. This surgical technique is known to carry a high risk of deadly complications for patients and current adhesive options have several limitations that reduce their use and performance. A team at the Massachusetts Institute of Technology (MIT) led by Xuanhe Zhao aims to revolutionize the technique, as reported in a manuscript published in Science Translational Medicine, where they describe a ready-to-use, biocompatible, biodegradable, and bioadhesive patch for the repair of GI defects.
What did these researchers do?
With duct tape as their inspiration, the team developed an off-the-shelf bioadhesive patch to repair GI defects. This thin, flexible, and transparent patch has mechanical properties matching native GI tissue. It also binds strongly in a matter of seconds, unlike current technologies which can take up to several minutes. The GI patch demonstrated biocompatibility comparable to that of the U.S Food and Drug Administration (FDA) approved, already commercially available tissue adhesive, and it was additionally degradable long term, reducing in size and weight 12 weeks after implantation. The patch also presented mechanical properties and adhesive performance far superior to the currently available technologies. This patch was tested in animal models (rats and pigs) and the team showed successful sealing of defects in the colon, stomach, and small intestine, without the use of sutures.
Flexible and transparent GI bioadhesive patch by X. Zhao Lab
Why is this important?
Suturing of GI defects is associated with a high rate of leaks and an increased risk of infection that can lead to death. Different technologies, such as surgical staples, tissue adhesives, and sealants, have been developed to reduce the risk of wound healing failure, but they don’t provide a truly robust or easy repair of GI defects. Surgical staples, for instance, cause additional tissue damage and generate higher localized stress in the tissue, while tissue adhesives and sealants are in suboptimal forms which require further preparational steps or the use of additional devices to provide an external stimulus to initiate tissue sealing. There is a clear need for an easy-to-use technology able to repair GI defects without the need for additional devices or for damaging surrounding tissue while trying to aid in the healing of a wound.
How did the researchers do this?
The team at MIT, using off-the-shelf materials, developed an adhesive hydrogel patch with two layers: a non-adhesive backing layer (hydrophilic polyurethane), and a dry adhesive layer (poly(acrylic acid) N-hydroxysuccinimide ester and polyvinyl alcohol). A third layer can be added on top of the non-adhesive layer to improve handling of the patch. Unlike current tissue adhesives and sealants, this patch comes ready-to-use (whereas most others require multiple steps and tools for application). The patch was successfully tested in live rats and pigs, sealing GI defects.
What comes next?
The work presented in this study is a promising surgical adhesive for the repair of GI defects. Additional studies should be planned to benchmark this technology to current technologies, and to improve its performance. This patch has been tested on simple surgical cuts, but can it seal a wound in a more complicated surgical setting? For example, a more extreme condition would be a leak that is already occurring where digestive fluids are already present. The performance of the GI patch needs to be assessed when exposed to different injury environments. During this validation and optimization process, extensive testing and the resultant feedback from practicing surgeons will be essential in order to optimize a user-friendly patch. Ideally, this GI patch could be tested in other clinical scenarios, aiding in the repair of other organs and injuries. Further studies should also evaluate the degree of inflammation and fibrosis, degradability, and the long-term stability of the repaired defect. Future studies should also evaluate if this technology is best used in isolation or in combination with sutures and/or staples. Nevertheless, this patch has the potential to be highly useful for patients who undergo surgeries for bowel cancers, inflammatory bowel disease, and other GI conditions.