138 Evaluation of Healing Outcomes Combining Negative Pressure Wound Therapy with Autologous Skin Cell Suspension and Meshed Autografts: Pre-Clinical and Clinical Evidence

Abstract

\n \n \n Negative pressure wound therapy (NPWT) is an option for securing meshed split thickness skin grafts (mSTSGs) after burn excision to optimize skin graft adherence, working by minimizing disruption by shear forces and promoting the continual removal of wound bed drainage. Recently, the use of autologous skin cell suspension (ASCS) has been approved for use in treating full-thickness burn injuries in conjunction with mSTSGs. Limited data exists regarding the impact of NPWT on healing outcomes when the cellular suspension is utilized. It was hypothesized that NPWT in conjunction with ASCS+mSTSGs would aid in skin graft adherence without compromise to healing outcomes.\n \n \n \n In this study, a Duroc pig model of burn, excision, mSTSG, ASCS + NPWT was used (n=2), where each animal had 2 sets of paired burns. Four wounds received mSTSG+ASCS+NPWT through post-operative day 3, and 4 wounds received mSTSG+ACSC+ traditional ASCS dressings. Percent re-epithelialization was measured using digital planimetry and Image J. Graft-adherence was evaluated using a scale with blinded reviewers (0=no graft loss, 4= >50% graft loss). Histological architecture, pigmentation, elasticity, and blood perfusion and blood vessel density were assessed at multiple time points through 2 weeks. After the evaluation of its effectiveness in animal models, the same surgical technique, including NPWT, was used in patients with full-thickness burns (n=9), and wound healing trajectories were described.\n \n \n \n In the Duroc pig study, all wounds healed within 14 days with minimal scar pathology and no significant differences in percent re-epithelialization between NPWT and non-NPWT wounds were observed (61.09 ± 9.01 and 61.15 ± 0.82% at Day 7). Additionally, no differences were detected for pigmentation, perfusion, or blood vessel density. Overall, the non-NPWT group had higher amounts of graft loss (1.0 ± 1.41 vs. 0 ± 0). NPWT-treated wounds had significantly improved elasticity (NPWT=109.5 ± 21.23 vs. non-NPWT=177.5 ± 35.4, p< 0.05). There were no differences in histological architecture between treatment groups. Patients had a median age of 53 (37–69), and median TBSA of 12.5 (8–18) resulting primarily from scald burns (67%). There were no reported morbidities, and all wounds were re-epithelialized within an expected time period. The use of NPWT promoted graft adherence, and was useful as a bolster dressing in wounds that crossed joints.\n \n \n \n These data suggest the positive attributes of the cellular suspension delivered are retained following the application of NPWT. Re-epithelialization, revascularization, and repigmentation are not adversely impacted.\n