J Pediatr Surg

. 2023 Jan 19;S0022-3468(23)00055-6.

 doi: 10.1016/j.jpedsurg.2023.01.036. Online ahead of print. https://pubmed.ncbi.nlm.nih.gov/36797111/

Evaluation of a biodegradable polyurethane patch for repair of diaphragmatic hernia in a rat model: A pilot study

Christina M Theodorou ¹, Alan Taylor ², Su Yeon Lee ¹, Lia Molina Cortez ², Huikang Fu ², Christopher D Pivetti ³, Chaoxing Zhang ³, Anastasiya Stasyuk ¹, Dake Hao ³, Priyadarsini Kumar ³, Diana L Farmer ³, Jun Liao ², Erin G Brown ¹, Yi Hong ⁴, Aijun Wang ⁵

Affiliations expand

• PMID: 36797111
• DOI: 10.1016/j.jpedsurg.2023.01.036

Abstract

Introduction: Congenital diaphragmatic hernia (CDH) repair is an area of active research. Large defects requiring patches have a hernia recurrence rate of up to 50%. We designed a biodegradable polyurethane (PU)-based elastic patch that matches the mechanical properties of native diaphragm muscle. We compared the PU patch to a non-biodegradable Gore-Tex™ (polytetrafluoroethylene) patch.

Methods: The biodegradable polyurethane was synthesized from polycaprolactone, hexadiisocyanate and putrescine, and then processed into fibrous PU patches by electrospinning. Rats underwent 4 mm diaphragmatic hernia (DH) creation via laparotomy followed by immediate repair with Gore-Tex™ (n = 6) or PU (n = 6) patches. Six rats underwent sham laparotomy without DH creation/repair. Diaphragm function was evaluated by fluoroscopy at 1 and 4 weeks. At 4 weeks, animals underwent gross inspection for recurrence and histologic evaluation for inflammatory reaction to the patch materials.

Results: There were no hernia recurrences in either cohort. Gore-Tex™ had limited diaphragm rise compared to sham at 4 weeks (1.3 mm vs 2.9 mm, p = 0.003), but no difference was found between PU and sham (1.7 mm vs 2.9 mm, p = 0.09). There were no differences between PU and Gore-Tex™ at any time point. Both patches formed an inflammatory capsule, with similar thicknesses between cohorts on the abdominal (Gore-Tex™ 0.07 mm vs. PU 0.13 mm, p = 0.39) and thoracic (Gore-Tex™ 0.3 mm vs. PU 0.6 mm, p = 0.09) sides.

Conclusion: The biodegradable PU patch allowed for similar diaphragmatic excursion compared to control animals. There were similar inflammatory responses to both patches. Further work is needed to evaluate long-term functional outcomes and further optimize the properties of the novel PU patch in vitro and in vivo.

Level of evidence: Level II, Prospective Comparative Study.

Keywords: Bioengineering; Congenital diaphragmatic hernia; Diaphragmatic hernia repair; Patch repair.

Copyright © 2023 Elsevier Inc. All rights reserved.