(WHS-L3.05) FINITE ELEMENT ANALYSIS, PRECLINICAL, AND PROTEOMIC ASSESSMENT OF A NOVEL 7-DAY EXTENDED WEAR PEEL AND PLACE NEGATIVE PRESSURE WOUND THERAPY DRESSING
Thursday, May 16, 2024
10:30 AM – 11:30 AM East Coast USA Time
Problem: Negative pressure wound therapy (NPWT)* with reticulated open cell foam (ROCF)^ necessitates frequent dressing changes as tissue ingrowth may occur if left in place for greater than 72 hours.
Objective: These studies evaluated key wound healing-associated characteristics of a novel NPWT peel and place dressing† designed for extended wear use.
Methods: Finite element analysis (FEA) was conducted using computer simulation to evaluate the effects of NPWT on tissue deformations produced by the peel and place dressing. Wound models were developed, with clinical input, incorporating dimensional specifications and material properties for the relevant tissue layers (epidermis, dermis, subcutaneous fat, muscle, and bone). An additional preclinical assessment was conducted using a swine model with full-thickness, excisional paraspinal wounds in 11 animals, and continuous -125mmHg NPWT for 7 days. The study was designed to assess long term wear; therefore, no dressing changes were performed throughout the 7-day study. The wounds were dressed with either peel and place dressing or ROCF. Biopsies were collected for protein extraction and tissues excised for histology at study termination. The extracted protein was assessed using a multiplex immunoassay to quantify wound healing biomarkers, and histologic morphometry was used to measure granulation tissue thickness. The study was approved by an Institutional Animal Care and Use Committee (IACUC) and animal care complied with all applicable national and local regulations.
Results: FEA revealed homogenous tissue displacements, uniform tissue tensile strains, and notable volume of tissue engagement. Preclinical results demonstrated significantly more granulation tissue than ROCF (p < 0.05) with tissue ingrowth being limited to only the ROCF treatment (p < 0.0001). Proteomic analysis of wound healing-associated cytokines/chemokines and heparin-binding endothelial like growth factor (HB-EGF) demonstrated elevated levels of interleukins (IL)-1α, IL-1β, IL-1ra, IL-8, IL-12, and HB-EGF in the peel and place dressing treatment as compared to ROCF (p < 0.05).
Conclusion: Greater mechanical stimulation generated by the peel and place dressing, as illustrated by FEA, is likely to have contributed to cell signal transduction, promoting elevated levels of wound healing biomarkers. The elevated presence of these critical biomarkers, in turn, supported greater granulation tissue formation promoted by the peel and place dressing. This outcome, along with mitigated tissue ingrowth, support the effectiveness of the peel and place NPWT dressing for 7-day extended-wear. *3M™ V.A.C.® Therapy; ^3M™ V.A.C.® Granufoam™ Dressing; †Peel and Place Dressing (3M, San Antonio, TX)