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bioRxiv · 10.1101/2021.03.12.435203

An Off-the-Shelf Bioadhesive Patch for Sutureless Repair of Gastrointestinal Defects

Wu, J.·Yuk, H.·Sarrafian, T. L.·Guo, C.·Griffiths, L. G.·Nabzdyk, C. S.·Zhao, X.
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Abstract

Surgical sealing and repair of injured and resected gastrointestinal (GI) organs are critical requirements for successful treatment and tissue healing. Despite being the standard of care, hand-sewn closure of GI defects using sutures faces various limitations and challenges. The process remains technically complicated and time-consuming. The needle-piercing and pointwise closure also inflict tissue damage and stress concentration, raising the risk of local failure and subsequent anastomotic leaks. To address these limitations and challenges, we introduce an off-the-shelf bioadhesive GI patch capable of atraumatic, rapid, robust, and sutureless repair of GI defects. The GI patch synergistically integrates a non-adhesive top layer and a dry bioadhesive bottom layer, resulting in a thin, flexible, transparent, and ready to use dressing with tissue-matching mechanical properties. Rapid, robust, and sutureless sealing capability of the GI patch is systematically characterized based on various standard tests in ex vivo porcine GI organ models. In vitro and in vivo rat models are utilized to validate biocompatibility and biodegradability of the GI patch including comprehensive cytotoxicity, histopathology, immunofluorescence, and blood analyses. To validate the GI patchs efficacy in a clinically relevant setting, we demonstrate successful sutureless in vivo sealing and healing of GI defects; namely in rat stomach and colon, and porcine colon injury models. The proposed GI patch not only provides a promising alternative to suture for repair of GI defects but also offers potential clinical opportunities in the treatment and repair of other organs. One Sentence SummaryAn off-the-shelf bioadhesive patch is introduced for facile sutureless repair of gastrointestinal defects, addressing various limitations of conventional suture-based treatments.

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Wu, J., Yuk, H., Sarrafian, T. L., Guo, C., Griffiths, L. G., Nabzdyk, C. S., Zhao, X.. 2021-03-12. An Off-the-Shelf Bioadhesive Patch for Sutureless Repair of Gastrointestinal Defects. https://doi.org/10.1101/2021.03.12.435203

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