Dates
Location
8:00 A.M. - 8:15 A.M.
Alan Wells, MD, DMSc; Swathi Balaji, PhD; Paul Bollyky, PhD
8:15 AM - 9:15AM
Judith Campisi, PhD
Details
9:15 A.M. - 9:30 A.M.
9:30 A.M. - 10:30 A.M.
W.J.H. Koopman, PhD; Hillary Coller, PhD
Details
10:30 A.M. - 11:30 A.M.
Gina Griffith, MD; Cheng-Ming Chuong, MD, PhD
Details
11:30 A.M. - 11:45 A.M.
11:45 A.M. - 12:45 P.M.
Kanhaiya Singh, PhD; Aristidis Veves, MD MS Dsc; Kaushal Rege, PhD
Details
12:45 P.M. - 2:00 P.M
Vickie Driver, DPM; Mitchell Sanders, PhD; Gary Robinson, PhD
Details
2:00 P.M. - 3:00 P.M.
Min Zhao, MD, PhD; Janis T. Eells, PhD (Virtual Pre-Recording)
Details
3:00 P.M. - 4:00 P.M.
Sundeep G. Keswani, MD; Katherine A. Gallagher, MD
Details
4:00 P.M. - 4:15 P.M.
4:15 P.M. - 5:15 P.M.
Rivka Stone, MD, PhD
Details
6:30 P.M. - 9:30 P.M.
Registered WHS members are invited to attend. Location: Phoenix Botanical Gardens (Transportation Provided)
7:00 A.M. - 9:00 A.M.
9:00 A.M. - 9:15 A.M.
9:15 A.M. - 10:30 A.M.
Marcus Engel
Details
10:30 A.M. - 10:45 A.M
10:45 A.M. - 11:45 P.M.
Indranil Sinha, MD
Details
11:45 A.M. - 12:00 P.M.
12:00 P.M. - 1:30 P.M.
1:30 P.M. - 1:45 P.M.
1:45 P.M. - 4:00 P.M.
Alan Wells, MD, DMSc; Daria A. Narmoneva, PhD; Amelie Reigl, PhD
Details
4:00 P.M. - 4:15 P.M.
4:15 P.M. - 5:15 P.M.
Marco Romanelli, MD, PhD; Sadanori Akita, MD, PhD
5:15 P.M. - 7:45 P.M.
7:30 A.M. - 9:00 A.M.
9:00 A.M. - 9:15 A.M.
9:15 A.M. - 10:15 A.M.
Marcus Engel
Details
10:15 A.M. - 10:30 A.M.
10:30 A.M. - 11:30 A.M.
Details
Mithun Sinha, PhD; Brian Schmidt, PhD
Adrian Barbul, MD; Amelie Reigl, PhD
Laura K.S. Parnell, BS, MS, CWS; Jane Kim, PhD
Allen Holloway, MD; Carlos Zgheib, PhD
11:30 A.M. - 2:00 P.M.
12:15 P.M. - 2:00 P.M.
Teresa Jones, MD; Robert Gersch, PhD
Details
2:00 P.M. - 2:15 P.M.
2:15 P.M. - 3:15 P.M.
Sebastian Probst, MD; Alberto Piaggesi, MD, PhD(Virtual Recording); Prof. Thomas Bjarnsholt (Virtual Recording)
Details
3:15 P.M. - 3:30 P.M.
3:30 P.M. - 4:30 P.M.
Geoffrey C. Gurtner, MD; Matthew Porteus, PhD
Details
4:30 P.M. - 5:00 P.M.
5:00 P.M. - 5:15 P.M.
5:15 P.M. - 5:45 P.M.
Daria A. Narmoneva, PhD; Carlos Zgheib, PhD, MS
Details
5:45 P.M. - 6:00 P.M.
6:00 P.M. - 7:00 P.M.
Geoffrey C. Gurtner, MD Robert S. Kirsner, MD, PhD; Rodica Pop-Busui MD, PhD; Gayle Gordillo, MD; Michael S. Conte, MD; Marjana Tomic-Canic, PhD; Cathie Spino, ScD; Chandan K. Sen, PhD; Brian M. Schmidt, DPM; Teresa Jones, MD; Sashwati Roy, PhD; Aristides Veves, PhD
Details
7:00 P.M. - 8:30 P.M.
**POSTER PRESENTERS SHOULD ATTEND THIS ENTIRE EVENT**
9:15 A.M. - 10:15 A.M.
Kyle P. Quinn, PhD; Marco Romanelli, MD, PhD; Chelsea Larsen
Details
10:15 A.M. - 10:30 A.M.
10:30 A.M. - 11:30 A.M.
Details
Daria Narmoneva, PhD; Lindsay Steele, PhD
Jaideep Banerjee, PhD; Amanda Spielman, PhD
John Gwin, PhD; Lauren Buchanan, PhD
Kanhaiya Singh, PhD; Amitava Das, PhD; Proma Basu, PhD
11:30 A.M. - 12:00 P.M.
12:00 P.M. - 1:00 P.M.
Geoffrey C. Gurtner, MD; Dot Weir, RN
Details
1:00 P.M.
11:30 A.M. - 2:00 P.M.
N1.01.
CD4+ T-lymphocytes are essential in regulating dermal fibrosis. SCID mice, which lack lymphocytes, heal with worse angiogenesis and fibrosis compared to wild type mice. We have demonstrated that IL-10-producing type 1 regulatory T lymphocytes(Tr1) improve vascularity in the healing wound, accelerate wound closure, and reduce dermal fibrosis in SCID mice. How the immune-modulatory Tr1 regulate angiogenesis is unknown. We therefore hypothesize that Tr1 modulate the pro-angiogenic cytokine balance(VEGF;CXCL12;MIF) to improve fibroblast and endothelial cell angiogenic functions, thereby enhancing neovascularization and wound healing outcome.
Methods:
10BiT murine(M/F;8-12wk) splenocytes were sorted into Tr1 precursors and Naïve T-lymphocytes(Tnaïve). In vitro, dermal fibroblasts were co-cultured with Tnaïve or Tr1 for 24h and gene expression of VEGF and CXCL12 was measured using qRT-PCR. Dermal endothelial cells were cultured with conditioned medium from Tr1 or Tnaïve and branching assay was performed. In vivo, we made 6mm bilateral dorsal full-thickness splinted wounds on SCID or C57BL/6J(WT) mice(female,8-10wk), followed by adoptive transfer of 10^6 Tr1 cells. Wounds were harvested at days 3,7,30. D3 wound protein was measured for VEGF, CXCL12, and MIF. Angiogenic and inflammatory cellular interactions were visualized with imaging mass cytometry(IMC) at D7. D30 wounds were examined for dermal architecture and neovascularization(H&E;CD31).
Results:
Fibroblasts co-cultured with Tr1 had increased expression of VEGF(1.5 fold increase;p<0.001) and CXCL12(1.5 fold increase;p<0.05) compared to untreated fibroblasts. Endothelial cells treated with Tr1conditioned medium demonstrated significantly greater branching and network formation(6.05ą0.15 vs 4.37ą0.56mm, p<0.05). Compared to WT, SCID mice deficient in T-lymphocytes showed abnormally elevated wound VEGF levels at D3(325.3ą24.6 vs 187.4ą42.1 pg/mg total protein, p<0.05), and treatment with Tr1 normalized VEGF in SCID mice to levels similar to WT(177.8ą55.5 pg/mg total protein). Similarly, the positive effect of Tr1-treatment was seen in normalizing the CXCL12 expression in D3 SCID wounds(SCID:1.8ą0.5 vs WT:0.6ą0.4, SCID+Tr1:0.8ą0.5 ng/mg total protein, p<0.05). MIF levels were also reduced by Tr1-treatment in D3 SCID wounds(SCID:800.6ą86.2 vs SCID+Tr1 ng/mg total protein, p<0.01). IMC performed on D7 wounds revealed more mature vessels(?SMA positive) with close cellular approximation of transferred Tr1 cells, indicating their paracrine effects on angiogenesis. WT mice wounds enriched with Tr1 application to wounds at the time of wounding resulted in improved wound maturation with a basket weave collagen structure, more dermal appendages, and increased neovascularization at D30.
Conclusions:
Tr1 improve the balance of angiogenic modulators VEGF, CXCL12, and MIF to promote improved neovascularization and scarring. Enrichment of Tr1 to wounds may be a therapeutic target to enhance wound healing.
N1.02.
Background
Repair after tissue injury involves a dynamic interplay among not just tissue resident cells (e.g., fibroblasts), but also cells recruited from the circulation. Myeloid cells, such as monocytes and macrophages, are derived from hematopoietic precursors and migrate to sites of injury where they play a role in modulating all stages of wound healing and scar formation. There is mounting evidence that mechanical stimuli are also able to modulate monocyte and macrophage response during tissue healing, but the exact mechanisms behind this “mechano-immunomodulation” remain incompletely understood.
Methods
We attached a mechanical strain device to the mouse dorsum to initiate a uniform and consistent strain profile across an incisional wound to create hypertrophic scar (HTS) formation in mice. To investigate mechano-responsive immune cells, we performed parabiosis of wildtype (WT) and GFP+ mice, allowed the mice to develop a shared blood circulation, initiated HTS formation in the WT mouse, and analyzed the cells using single cell RNA sequencing (scRNA-seq), fluorescent-activated cell sorting (FACS), and immunofluorescent staining.
Results
Mechanical modulation significantly upregulated the presence of inflammatory subtypes within the healing tissue, characterized by an increase in infiltrating GFP+ cells from 5.4% to 12.2%. In the GFP+ circulating cells, mechanical strain directly increased the proportion of fibrotic myeloid cells, primarily defined by the monocyte marker Ly6c2 as well as the TGFB responsive and macrophage activating gene Thbs1. Mechanical strain also increased the proportion of inflammatory myeloid cell populations, defined by Ccl and Il6 chemoattractants, and Cd74+ migratory myeloid cells. Utilizing both a pharmacological blocker of focal adhesion kinase (FAK) as well as a myeloid specific FAK knockout (KO), we demonstrated that modulating mechanical signaling abrogated those responses and instead promoted homeostatic myeloid transcriptional fates.
Conclusions
Tissue injury activates a cascade of signaling pathways to recruit and orchestrate various cell types during healing. Our study indicates that modulating mechanical stress directly affects myeloid cell phenotypes and interactions with other cell types in the complicated, multicellular milieu of wound healing. This principle has been previously unexplored in the context of fibrosis and regeneration, with most previous studies focused on fibroblast heterogeneity and transcriptional profiles. To our knowledge, this is the first study to directly investigate the effects of modulating mechanotransduction on immune cell response at the single cell level utilizing parabiosis and wound healing. Collectively, we demonstrate that mechano-immunomodulation of the “early responders” of healing can trigger a cascade of downstream regenerative healing.
N1.03.
N1.04.
N1.05.
N1.06.
Critical limb threating ischemia (CLTI) is a severe form of peripheral arterial disease with markedly reduced blood flow in lower extremities. Type 2 diabetes mellitus increases the incidence and severity of CLTI by 2-4-fold. Hyperglycemia induced endothelial cell dysfunction is recognized as a contributor to such limitation. For CLTI, VEGF therapy has met with limited success. To address such limitation, we applied single-cell RNA sequencing (scRNA-seq) technology to study the endothelial cells of the human diabetic skin. Single-cell suspensions were generated from the human skin followed by cDNA preparation using Chromium Next GEM Single Cell 3′ Gel Bead Kit v3.1(10x Genomics, Inc.) and sequenced on NovaSeq 6000 (Illumina, Inc). Using our published quality control measures, 36,487 cells (from 3 diabetic skin and 5 non-diabetic skin) were chosen for downstream analysis. Global communications analyses of scRNA-seq data using CellChat identified that although VEGF signaling was not significantly altered in diabetic vs non-diabetic skin, phospholipase C Gamma 2 (PLCG2) was significantly down-regulated. The significance of PLCG2 in VEGF mediated increase in endothelial mitochondria function was assessed in cultured human microvascular endothelial (HMEC) cells using extracellular flux (Seahorse™) assay. In HMEC, VEGF enhanced mitochondrial function as indicated by elevation in oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). PLCG2 inhibition impaired the action of VEGF on mitochondrial metabolism (n = 5, *P < 0.05, one-way ANOVA). Follow-up rescue studies therefore focused on understanding the significance of VEGF therapy in presence or absence of endothelial PLCG2 in murine diabetic ischemic tissue. Non-viral tissue nanotransfection technology (TNT2.0) mediated delivery of PLCG2 to endothelial cells was achieved through cadherin-5 promoter driven PLCG2-ORF. Targeted delivery of endothelial PLCG2 promoted the rescue of hind-limb ischemia in diabetic mice (n = 6, *P < 0.05, one-way ANOVA). Improvement of blood flow was also associated with higher abundance of VWF+/CD31+ and VWF+/SMA+ immunohistochemical staining (n = 6, *P < 0.05, one-way ANOVA). TNT-based gene delivery was tolerated well by diabetic ischemic tissue. Taken together, this work identifies endothelial PLCG2 as an important contributor to the success of VEGF therapy in a diabetic ischemic limb setting.
N1.07.
N1.08.
IRD1.
IRD2.
Background: Negative pressure wound therapy (NPWT) drape removal from skin may be painful for patients and inadvertently cause skin damage during the length of therapy. Most NPWT drapes utilize an acrylate adhesive to achieve the seal. To improve the experience associated with NPWT drape removal, a novel hybrid drape was developed. This drape is composed of areas of acrylate adhesive and areas of silicone adhesive. To more fully understand how removal of the hybrid drape versus the acrylate drape affects skin, adhesive removal models have been developed. Existing medical adhesive removal test methods include measuring peel forces during medical product removal from steel, acrylic resin products, or skin. However, the peel force may not be representative of the actual strain that the product imparts to tissue. The current study assessed the differences in strain profiles for acrylate versus hybrid NPWT drapes using a finite element analysis (FEA) to measure strain and deformation that occurs at the tissue interface with the NPWT drape.
Methods: A skin mimic was created from a two-part silicone molding material. The surface of the skin mimic was a polyurethane film. Three NPWT drapes were tested: one acrylate adhesive* drape and two hybrid acrylate plus silicone adhesive drapes (hybrid drape 1 and hybrid drape 2). The drapes were placed on the skin mimic and a high-speed camera captured the NPWT drape removal. The 180-degree peel force was captured at the same time. FEA models of the drapes and drape removal were based on mechanical test data of the drapes as well as the peel force data.
Results: The FEA modeling showed that the maximum principal strain associated with removal of the acrylate drape was 47.3%, whereas the maximum principal strain associated with the removal of hybrid drape 1 was 21.5% and hybrid drape 2 was 16.1%. The average peel force associated with the acrylate drape was 66.1 gf/in, hybrid drape 1 was 112.5 gf/in, and the hybrid drape 2 was 92.2 gf/in. The hybrid adhesive drape had the highest peel force and the lowest skin strain.
Conclusions: NPWT drape removal may, in certain instances, be related to pain and periwound skin injury. This hybrid drape may provide clinicians an option for NPWT that is gentle to skin.
*3M™ V.A.C.® Drape (3M, Maplewood, MN)
IRD3.
IRD4.
IRD5.
IRD6.
PURPOSE: Infection is the most likely single cause of delayed healing in chronic wounds. Recent study shows that infected wounds have elevated leukocyte esterase activities as compared with non-infected wounds as determined by a portable device – Detec® Esterase. Here we investigated whether the same device, Detec® Esterase, can be used to screen and diagnose the infection of diabetic foot ulcer (DFU) and venous leg ulcer (VLU) at point-of-care.
METHOD: Wound dressings from 71 DFU patients and 31 VLU patients at the Texas Health Arlington Memorial Wound Care and Limb Salvage Clinic were tested with DETEC® esterase and the device output was compared with subsequent clinical determination of infection on the same wounds. We evaluated the efficiency of the device through sensitivity, specificity, accuracy, and the increase in post-test risk of infection with positive test result.
RESULTS: For DFU patients, the results show that DETEC® Esterase device had good sensitivity (89.8%), fair specificity (45.5%), moderate accuracy (76.1%), and the increase in post-test risk of infection with positive test result of 9.56%. As for VLU patients, the results show that DETEC® Esterase device had comparably good sensitivity (82.1%), moderate specificity (66.7%), good accuracy (80.6%), and a smaller increase in post-test risk of infection with a positive test result of 5.51% because of high prevalence of the condition. Through fisher’s exact test to compare the diagnosis efficiency between DFU and VLU, two tailed p-values for sensitivity, specificity, and accuracy are 0.4825, 0.593, and 0.7975, respectively. Therefore, there are no significant differences in the device diagnosis efficiency between two different wounds. Using a logistic regression model, we determined whether other factors (such as age, gender, race, initial wound size, wound location, and sign of infection) would affect the accuracy of DETEC® Esterase device on diagnosis of infection and found none of these factors has significant effect on diagnosis accuracy of DETEC® Esterase device (age, P=0.4597; gender, P=0.1886; race, P=02401; initial wound size, P=0.9020; wound location, P=0.8549; signs of infection, P=0.456).
CONCLUSION: Our results support that DETEC® esterase can effectively and accurately diagnose and/or screen for infections in DFUs and VLUs. The diagnosis accuracy of the device is not influenced by the patients’ age, gender, race, initial wound size, wound location, and sign of infection.
IRD7.
Background: About one-fifth of diabetes-related hospitalizations are the result of complications from delayed wound healing and pathogen colonization, leading to ~100,000 non-trauma-induced lower-limb amputations per year and ~35,000 deaths in the US each year due to the rise of antibiotic-resistant strains of bacteria. The objective of this research is to develop a flowable cell delivery scaffold to promote tissue regeneration in clean and pathogen-contaminated diabetic wounds. Hypothesis: This shear-thinning-self-assembling-peptide gel matrix (G4matrix) encapsulated with mesenchymal stem cells (MSCs) enhances implanted cell survival and promotes healing in both clean and pathogen-contaminated diabetic wounds vs. control (PBS + MSCs). Methods: 5-mm full-thickness, splinted, excisional wounds (n= 50 mouse, 2 wounds/mouse) are created on the dorsum of each mouse. Tissues were collected at days 2 and 21 post-wounding for further analysis. Results: The G4matrix used in this research are effective against Pa and MRSA. We demonstrated complete clearance of 106 CFU (MRSA) and complete clearance of 106 CFU (Pa) which was significantly (p<0.0001) higher than a non-antimicrobial matrix control. To confirm cell viability, we encapsulated MSCs in G4 matrices for 24 hours and used a luciferase-based assay to quantify cell viability using Relative Luminescence Units (RLU). We demonstrated significantly higher cell viability in G4matrix (p<0.0001) compared to gelatin, our positive control, and PBS. MSCs encapsulated in G4matrix resulted in significant (p < 0.02) reduction in the wound area of non-contaminated wounds at day 21 versus control (PBS + MSCs). Similarly, at day 21, wounds were found to have complete healing with immature epithelium over the center of the wounds for clean wounds. Furthermore, H&E staining of sectioned wound tissue from pathogen-contaminated wounds demonstrated that the wounds treated with G4matrix + MSCs have robust granulation tissue and re-epithelialization with significantly lower edema (p <0.001) at days 2 and 21, and significantly lower leukocyte infiltrate levels (p < 0.02) at days 2 vs. controls. Conclusion: G4matrix + MSCs improved wound closure in non-contaminated and decreased markers of inflammation in contaminated wounds as compared to untreated controls.
P1.
P2.
P3.
P4.
P5.
P6.
P7.
P8.
P9.
P10.
Background
The newly-approved Kerecis is a piscine acellular dermal xenograft. This piscine acellular dermal matrix (ADM) has specific bioactive lipid mediators, omega-3 polyunsaturated fatty acids, and has a positive effect on the process of wound healing. This study aimed to explore the utility of this novel material by comparing healing rates, and suggest the proper timing for applying Kerecis.
Methods
Patients who visited the hospital with acute or chronic deep dermal wounds from June 2019 to May 2020 were enrolled in the study. A total of 48 patients were assessed. All wounds in the experimental group (n=16) were treated only once with Kerecis and a non-adherent absorptive foam material (Therasorb) to cover the ADM. In the control group, daily conventional dressings were provided. All wounds sizes were measured with mass-market computer software in a method suggested by the authors for the first time.
Results
The mean healing rate proved to be faster in the Kerecis group (P<0.05) versus the control group, and no complications were observed. It was statistically proved that treating burn wounds with the ADM showed better healing rates than the conventional method (P<0.05).
Conclusion
This study establishes that managing wounds with the ADM is likely to heal wounds faster than traditional dressings. In addition, for burn wounds, a prolonged application (10 days vs. 5 days after the onset) showed a better wound healing rate (98.8%±2.5% vs. 67.0%±14.3%, respectively, P=0.029).
P11.
BACKGROUND: Antiviral and anti-inflammatory activity of a unique solution of Ag released from Acticoat was tested in standard lab and animal models. Clinical effects of nebulized inhalation of the Ag solution in ventilated patients with MDR bacterial pneumonia, TENS, and COVID-19 were assessed.
METHODS: Ag release kinetics was determined using integration of absorption spectra at 350-650 nm. Inactivation of hHSV1 and SARS-CoV-2 by the Ag solution, colloidal silver, or stable silver nanoparticles was assessed using the ASTM E1052–20 protocol for antiviral testing of agents in solution. Rat lungs infected for 24 hours with Pseudomonas aeruginosa were treated with lavage of silver solution, tobramycin, or water, and rat survival and lung histology were assessed at 48 hours. Anti-inflammatory activity of the Ag solution was assessed using a pig contact dermatitis model. Eight patients, six with burn wounds who developed MDR pneumonia, one with burns who developed COVID-19, and one with TENS, all of whom were placed on ventilators, were treated with nebulized inhalation of the Ag solution and clinical parameters were measured.
RESULTS Silver species (Ag0, Ag+, Ag3+) were rapidly released from the nanocrystalline silver dressing into distilled water at RT, reaching 50% saturation at 24 hours and 90% saturation at 48 hours with a concentration of ~400 mg/mL. The Ag solution inactivated hHSV1 by 4-logs and 5-logs at 4 and 24 hours, and inactivated 1-log and 6-logs of SARS-CoV-2 after 4 and 24 hours, respectively. Neither a colloidal silver product nor a stable Ag nanoparticle product inactivated hHSV1 or SARS-Cov-2 viruses. Lavage of infected rat lungs with the Ag solution prevented death and preserved normal lung tissue histology. Silver nitrate or tobramycin treatments did not prevent death, and massive inflammation and lung tissue destruction was observed histologically. The Ag solution was highly anti-inflammatory in the pig contact dermatitis model. Nebulized inhalation of the Ag solution via ventilator rapidly reversed clinical parameters in all six patients with MDR pneumonia, in the TENS patient, and the COVID-19-infected burn patient. Chest x-rays showed no evidence of silver deposits in lung tissues of any treated patients.
CONCLUSIONS Nebulized inhalation of a unique solution of Ag species released from the nanocrystalline silver wound dressing appears to be a highly effective new treatment for patients with MDR pneumonia, TENS, and COVID-19 due to its unique triple combination of antimicrobial, anti-inflammatory, and anti-viral actions.
P12.
BACKGROUND: Persister bacterial phenotypes such as small colony variants (SCV) are a subpopulation of antibiotic-tolerant bacterial cells that are often hyperbiofilm forming in nature. The key to managing such hostile biofilms of persister bacteria is complete eradication and one approach is to dismantle the structural framework of these biofilms. Extracellular DNA is a major component of the biofilm. DNase treatments can eradicate standard biofilms but not persister biofilms (iScience, 2019). Our work showed that, fragmented extracellular DNA (eDNA) released from a persister strain of Pseudomonas aeruginosa (PAO1?wspF) biofilm was responsible for resistance to disruption by DNase. PAO1?wspF biofilm can be disrupted by the drug aurine tricarboxylic acid (ATA), a chemical inhibitor of covalent binding between eDNA and protein. In this study, we tested the efficacy of GelATA wound care dressing (ATA incorporated into a polymer-based gel) against polymicrobial persister biofilm infection in a preclinical porcine burn wound model.
METHODS: Eight 2”x2” full thickness burn wounds were created on the dorsum of (70-80lb) female domestic white pigs (n=4) using a standardized method published by us. Polymicrobial biofilm infection was established with clinical isolates of P.aeruginosa (PAO1 ?wspF) and Staphylococcus aureus (S. aureus rexB). Wounds were treated with either standard of care dressing (ActicoatTM) or GelATA once weekly. At D28 postburn, treatment of GelATA treated wounds was switched to ElastogelTM alone until D56. Progression of wound healing was followed using non-invasive imaging: Digital images and Trans Epidermal Water Loss (TEWL). Histopathological examination and Scanning Electron Microscopy (SEM) of the burn wounds were performed at D56.
RESULTS: SEM imaging of GelATA treated wounds showed disrupted biofilm formation with less bacterial colonization compared to ActicoatTM treatment. Furthermore, GelATA significantly (p<0.05) enhanced wound closure and re-epithelialization of persister biofilm-infected wounds (p<0.05). Interestingly, improved wound closure with inhibition of biofilm formation resulted in functional healing which was evident by significant decrease in TEWL (p<0.05) and improved skin barrier function in GelATA treated wounds.
CONCLUSIONS: This work presents first in vivo evidence for the efficacy of ATA in disrupting persister biofilm and promoting improved wound closure, functional and as photographed, in a porcine burn wound model.
P13.
BACKGROUND: Critical Limb Ischemia (CLI) is the most severe and advanced stage of peripheral arterial disease (PAD), defined by impaired circulation to the lower extremities and characterized by ischemic rest pain, non-healing ischemic ulcers, and gangrene with both life and limb threatening complications. The reported similarities of the vascular and immunological systems between humans and pigs makes the porcine model relevant for pre-clinical studies. Most of the currently reported preclinical models of CLI, including porcine, are inadequate to sustain long-term ischemia causing major tissue damage. Other approaches involving upstream vascular blockade are not specific for the limb and involve pelvic ischemia causing adverse effects. This work sought to develop a surgical approach wherein pelvic blood supply remains unaffected yet the limb suffers from ischemia such that skeletal muscle necrosis is evident.
METHODS: Unilateral CLI was induced by surgical transection of 1” of the common femoral artery (CFA) via infra-inguinal incision and retroperitoneal dissection in female domestic white pigs (n=5). X-ray arteriography (XRA) and computed tomography angiography (CTA) were done pre and post transection to assess the successful induction of ischemia up to d28. The effect of ischemia on limb function, perfusion, and degree of ischemic myopathy were assessed weekly by laser speckle imaging (LSI), CTA, XRA, femoral artery duplex ultrasound scans, and histologic examination.
RESULTS: Successful induction of CLI was achieved. Gait disturbance and limping were recorded in all pigs. XRA and CTA showed complete cessation of blood flow downstream of the CFA without jeopardizing the pelvic vessels and organs. Arterial duplex indicis (pulsatility index, resistive index and systolic to diastolic ratio) were significantly lower in ischemic limb compared to contralateral limb, demonstrating successful vessel occlusion and development of ischemia (p<0.05). Significant decrease in skin perfusion was evident in the ischemic limb (p<0.05). Ischemic myopathic morphological changes with inflammatory infiltrates were evident using H&E histological analysis, associated with architectural and biomechanical changes in muscle myofibers. Such findings were corroborated with ultrasound elastography findings of increased muscle stiffness.
CONCLUSIONS: This preclinical model robustly recapitulates features characteristic of human CLI and lends itself to mechanistic studies and therapeutic interventions.
P14.
Background and Objective
Non-healing wounds are a major cause of morbidity and mortality in collagen disease patients. Recently, we have reported the novelty of serum free ex vivo expansion system called Quantity and Quality Culture System (QQc) using peripheral blood mononuclear cells (PbMNC) as non-invasive and effective vascular and tissue regenerative cell therapy. After demonstrating high vasculogenic and wound healing potential of this technology with murine and porcine animals, we have begun enrolling collagen disease patients with non-healing wounds in a prospective phase I/II clinical trial. The objective of this study is to investigate the safety and efficacy of MNC-QQ therapy for these patients.
Material and Methods:
The first phase I study was performed by drawing 200ml of peripheral blood (PB) from collagen patients with chronic (>3 months) ischemic extremity ulcers. PbMNC were isolated and cultured in QQc for one week without passaging or media changes. Under local anesthesia, 2×107 MNC-QQc were injected within 20 cm2 of the wound. To obtain higher efficacy, we performed second stage phase I study by changing the protocol by lowering the blood draw to 100ml and injecting three times with one month interval in the calf and plantar area. The safety and efficacy were evaluated. Wound closure, VAS scale, skin perfusion pressure (SPP), TcPo2, laser doppler, thermography and angiography were performed to evaluate efficacy post therapy.
Results:
Two patients of Buerger`s disease and Scleroderma were enrolled in the first stage phase I study. One patient with Malignant rheumatoid in the second stage phase I study. All the wounds extended into bone or tendon and were in the digits of the hand and foot. No major adverse effects were observed. All patients did not undergo major amputation. Significant increase in vascular perfusion with decrease in VAS scale were seen in all patients.
Conclusion?
The outcomes of this prospective clinical study indicate the safety and feasibility of MNC-QQc cell therapy in patients with collagen ischemic nonhealing wounds. This methodology will allow us to transplant highly vasculogenic EPCs from small amount of blood draw. This will be the world`s first non-invasive and effective peripheral blood vascular stem cell therapy for limb salvage.
P15.
Healing wounds infected with bacteria requires agents that (1) overcome drug-resistant pathogens, (2) disrupt biofilms, and (3) reduce inflammation from pathogen associated microbial molecules (PAMPS). We show data that one molecule — 600 Da BPEI that is PEGylated to improve safety — accomplishes these 3 goals. PEG-BPEI potentiates common antibiotics against drug-resistant Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae. These pathogens both intrinsic and acquired antibiotic resistance, making clinical management of infection a real challenge, particularly when these bacteria are sequestered in biofilms. Against Enterobacteriaceae and their biofilms, the potency of ?-lactam antibiotics is restored with 600-Da branched polyethylenimine (600-Da BPEI). Checkerboard assays using microtiter plates demonstrate the potentiation of piperacillin, cefepime, meropenem, imipenem, and erythromycin antibiotics. Growth curves demonstrate that a combination of 600-Da BPEI and piperacillin produces bacteriostatic effects. Scanning electron microscopy (SEM) was used to confirm that the combination treatment leads to abnormal morphology. Data collected with isothermal titration calorimetry and fluorescence spectroscopy demonstrate a mechanism of action in which potentiation at low concentrations of 600-Da BPEI reduces diffusion barriers from lipopolysaccharides without disrupting the outer membrane itself. LPS also stimulates pattern recognition receptors, leading the release of pro-inflammatory cytokines. BPEI and PEG-BPEI bind to LPS to reduce cytokine production. Coupled with the ability to overcome reduce antibiotic activity and biofilms exopolymers, PEG-BPEI provides new opportunities to counter the rise of multidrug-resistant infections.
P16.
Introduction: Infection in surgical wounds is dangerous and costly, significantly increasing morbidity rates and often exceeding ,000 per case.1 Cultures from surgical site infections (SSIs) show that organisms specific to the endogenous flora of the anatomical region are the infection culprits. For example, Cutibacterium acnes is overrepresented in SSIs of the shoulders and breasts, but transdermal sites are commonly infected by Staphylococcus epidermidis and Staphylococcus aureus—standard skin flora members, suggesting that many SSIs derive from patients’ skin flora.2 We hypothesized that biofilm-dwelling organisms deep in the skin survive antiseptic skin preparation and contribute to infection during surgical wound healing. The purpose of this study was to quantify bacterial biofilm survivors in a porcine model following an on-label chlorhexidine gluconate (CHG) presurgical scrub.
Methods: Using 4% CHG surgical skin preparation, 40 skin samples were harvested from 5 Yorkshire pigs during surgery. Control data were collected using a sterile water scrub. Pieces were immediately transferred to sterile neutralizing broth. Following tissue processing, a serial dilution was performed and plated. Plates were incubated in aerobic and anaerobic conditions, and colony forming units (CFUs) were counted and normalized per g of tissue.
Results: Aerobic and anaerobic bacteria levels following surgical scrub were 4.021×103 ± 48 and 3.748×103± 52 CFU/g, respectively. Sterile water-scrubbed tissue had 2.275×104 ± 300 and 2.149×104 ± 340 CFU/g in aerobic and anaerobic conditions, respectively.
Discussion: The data suggest that bacteria survive an alcohol-CHG scrub and remain at infectious dose levels as surgical prep reduced the total bacteria by less than one log10 unit. With the presence of a foreign body (i.e. implanted biomaterials), infectious dose was reported as low as 102 using inoculated silk sutures3. In this model, skin prep with CHG was insufficient to eliminate deep-dwelling biofilms, indicating infection risk during surgical wound healing.
References: (1) Kurts et al. J Arthroplasty (2012). (2) Williams. Targeting Biofilms in Translational Research, Device Development, and Industrial Sectors (2019). (3) Elek and Conen. British J Exp Pathol (1957).
P17.
Purpose
The purpose of this study is to assess the healing of acute wounds treated with full thickness skin grafts processed by a novel skin morselizing device in an animal model
Introduction
Full thickness skin grafts, by the nature of their thickness and limited donor areas, are not optimal grafts for compromised graft beds or very large wounds. Full thickness grafts that could be morselized into thinner segments and spread out over larger areas would have the benefits of both the full thickness skin graft donor site and the expandability and thin profile of a split graft.
Methods
Full thickness wounds (2 X 2 cm) were made in the back of 3 Yorkshire Pigs in the experimental model for acute wounds in the skin graft experiment. The wounds were then treated with either morselized full thickness skin at 1:10 dilution expansion, 1:40 dilution expansion, or controls. The wounds were then treated with a 3-layer compression dressing. 2 animals were sacrificed at day 8 to assess histology and one animal was sacrificed at day 21, the end of the study. Digital images of the wound were taken at Day 0, 8, 14, and 21. Healing percentage was assessed by visual analysis with evaluation by 10 wound specialists.
Results
Results showed greatly reduced healing time in the morselized skin groups with the 1:10 dilution group showing the most rapid healing. This group showed a comparison of 10 percent versus 90 percent at 8 days for the control and 1:10 dilution respectfully. There was minimal difference between the fine and course morsels. All wounds were healed by day 21 of the study.
Conclusion
The skin grafting results were consistent with previous studies in the grafting of acute or clean wounds. Prospective human studies and wound stratification and will be needed to further access this skin grafting technology.
P18.
Background :
Antimicrobial triple therapy for Mycobacterium leprae is standard of care, however, there is a paucity of information detailing the treatment of these rare wounds’ care in contemporary world settings. The use of amniotic membrane stem cells and biomaterial scaffolds CTP has been used to expedite wound healing1, 2 in leprosy. This report describes the effective use of a non-human CTP matrix in a Hansen’s disease case.
Methods:
In April 2021, a 91 year old woman presented with right arm open ulcer. History between March 2020 and January 2021 included swelling and pain in the upper extremity, that had progressively worsened to new raised lesions and rash on trunk, and other limbs. She had no social or environmental risk factors. In March 2021, after an MRI showed an edematous skin ulcer, involving subcutaneous , biceps and brachioradialis muscles, she underwent an incisional biopsy. Diffuse non-caeseating granulomatous tissue was seen on path, with (+) AFB stains, confirmed DNA hsp65 PCR for Mycobacterium lepromatosis and negative immunostains for sarcoma, sarcoid and lymphoma.
On physical exam, the dehisced arm wound was tender with 25% necrosis, peri-wound erythema, and undermining of 2cm. X-rays were negative for osteomyelitis. Treatment consisted of repeated excisional debridement, cleansing with chlorohexidine, daily Prontosan (B.Braun Bethlehem,PA) and compression. She was referred to Bellevue hospital Hansen clinic; she was started on minocycline, and dapsone . Rifampin was added in July. Four applications of CTP (cross-linked extracellular matrix with polyhexamethylene biguanide (Pura Ply AM Organogenesis, Canton MA)) were used on the arm ulcer from July to August.
Results:
Initial presentation the wound measured 5cmx6.4cmx1.2cm (32cm2). Standard of care therapy was able to reduce size to 5cmx4.9cmx0.3cm (24.5cm2 ) in 78 days ( 0.096cm2 /day). After four applications of CTP, on triple therapy and collagen with silver, the wound closed (99 days, 0.247cm2/day).
Conclusion:
The adjunctive use of a cross-linked extracellular matrix with broad spectrum polyhexamethylene biguanide was an effective treatment modality in a patient confirmed to have Hansen’s disease with skin involvement. Use of non-human CTP for leprosy may help improve healing time for open ulcers, and complement triple therapy for granulomatous disease.
1.Natallya FR et al.Effective healing of leprosy chronic plantar ulcers by application of human amniotic membrane stem cell secretome gel.Indian J Dermatol,2019 May-Jun 64(3):250
2.Sivasubramanian,S. etal. Leprosy-associated chronic wound management using biomaterials. J Glob Infect Dis.2018 apr-jun;10(2):99-107
P19.
BACKGROUND: Effective wound healing requires a multitude of biologic processes. Key prerequisites include: adequate blood supply, robust granulation tissue ingrowth, increased re-epithelialization, and infection control.
STUDY GOAL: Identify the optimal routes of administration, doses, and delivery times for P12 that address the key prerequisites for effective wound healing.
METHODS: In vitro human dermal fibroblast and endothelial cell growth assays; in vivo small and large animal models to assess adequate blood supply, angiogenesis, granulation tissue formation, re-epithelialization, and rapid wound closure; and in vitro anti-bacterial assays.
RESULTS: Cyclized P12 (cP12), at optimal 0.01mg/kg iv dose in a porcine burn model, reduces microvascular occlusion by aggregated RBCs at 24h post-burn, increases re-epithelialization at 10d post burn (Asif et al. WRR 24:501-512,2016), and promotes wound closure at 14d post-burn (data submitted to an Investigation New Drug, IND, for cP12). Pharmacokinetics of cP12 porcine studies and a cP12 Phase 1 clinical trial showed that 0.01mg/kg cP12 iv gives blood concentrations of 100pM to 10nM over the first 2 hours of administration (data submitted to an IND for cP12). Importantly, P12 at 100pM-10nM dilates the mucocutaneous microvasculature of the hamster cheek pouch (Frame et al. Microcirculation 24:e12369,2017). Thus, 100pM to 10nM cP12 blood concentrations probably clear RBC aggregates from peri-burn microvasculature in our porcine burn model via microvascular dilation and thus promote burn wound healing. In contrast, P12 at 10–30uM promotes cultured fibroblast survival and growth by biasing platelet-derived growth factor-BB (PDGF-BB) activity toward cell survival/growth and away from apoptosis in vitro (Lin et al JID134:1119-1127,2014; Zhu et al JID 134:921-929,2014), and stimulates fibroblast migration in vitro (Prasad et al WRR27:634-649,2019). Furthermore, 10–30uM P12 also stimulates in vitro and in vivo human endothelial cell angiogenesis (see McTigue et al. 2022 WHS Abstract). Importantly, cP12 applied topically at 600uM promotes early healing in acute porcine wounds (likely 10-30uM concentration deep within the wound since the delivery vehicle is <1/10 volume of wound bed)(WRR 27:634-649,2019). Recently we found that cP12 is an anti-microbial peptide (AMP) as determined by sequence analysis and by bacterial growth inhibition (100nM-1uM) and bacterial killing (10uM or higher) of P aeruginosa and S aureus. Thus, 600uM P12 applied topically at the wound surface would be a strong anti-microbial.
CONCLUSIONS: The mechanisms of action of P12 are differentially concentration-dependent and therefore tunable by changing the route of administration, dose, and/or duration of delivery. Perhaps two routes of administration, e.g. cP12 iv and topically, might be synergistic.
P20.
Introduction: Infection is the most dangerous and costly postoperative complication, increasing morbidity rates and often exceeding ,000 per case.1 Cultures from surgical site infections (SSIs) show that organisms specific to the flora of the anatomical region are the infection culprits.2 This data suggests that most SSIs are derived from patients’ own skin flora. We hypothesize that bacteria is surviving a preoperative skin preparation of povidone iodine (PI), thus allowing bacterial survivors to contaminate surgical wound sites and contribute to infection. In this work, we quantified, biofilm-forming bacterial isolates that survived in porcine skin tissue following an on-label preoperative skin preparation with PI.
Methods: 40 porcine skin samples were harvested from five surgeries following an on-label use of PI 7.5% scrub and 10% paint surgical skin preparation kits. Control samples were collected from necropsies following a sterile water scrub for a baseline bioburden. Each sample was transferred to a sterile container with Dey-Engley neutralizing broth. Each sample was homogenized, vortexed, and sonicated. A 10-fold serial dilution was performed in duplicate. A representative count of colony forming units (CFUs) for the PI prepared skin and control skin were compared. To ensure sterility, the same procedure was performed with only Dey-Engley and plated to verify there was no contamination
Results: Aerobic and anaerobic bacteria CFUs following PI skin preparation were 1.20×103 of tissue and 7.36×102 CFU/g, respectively. Control tissue had approximately 2.27×104 and 2.15×104 CFU/g for aerobic and anaerobic, respectively.
Discussion: This data shows that PI may be insufficient to reduce biofilm burdens to below infectious dose levels. Additional work is needed to determine if bioburden levels are similar in human skin. Data indicate that if porcine and human skin respond similarly, surgeons using the very best aseptic technique and procedures may introduce significant levels of bacteria into surgical site wounds and contribute to post-operative infection.
References: (1) Kurts et al. J Arthroplasty (2012). (2) Williams. Targeting Biofilms in Translational Research, Device Development, and Industrial Sectors (2019).
P21.
PURPOSE: Sterile gloves are essential for complex wound care and reconstructive surgery, but little research has been published on glove fit. Sterile gloves sizes 5 1/2 – 9 are produced by all manufacturers. The finger lengths are fixed for all sizes. However, many wearers have fingers that are shorter or longer than usual, causing functional limitations secondary to incorrect glove finger length and fingertip fit.
METHODS: A multi question confidential electronic survey of sterile glove finger length fit was sent to 6180 glove wearers from 3 organizations; the American Society of Plastic Surgeons (ASPS), International Society of Plastic and Aesthetic Nurses (ISPAN), and the Association of Plastic Surgery Associates (APSA). Data was collected for this descriptive study in 2020 – 2021 and statistical analyses were performed using SPSS Version 2 Statistical Software.
RESULTS: The survey yielded 500 responses, with some respondents not answering all questions. The response rate from ASPS members was 8.2%, and 7.3% from all groups combined. Most survey responders were ASPS members (86.6%); 62.7% were male. 58% had 15 or more years working in plastic surgery. The most common reason for glove finger length dissatisfaction was fingers too long (41.6%).
Of all responders, 28.51% were very likely, and 16.01%, moderately likely, to want to use gloves with longer or shorter fingers if available, a total of 44.52%. For all males total likelihood of wanting such gloves was 38.28%, and for females the likelihood of wanting gloves with variable finger lengths was 56.97%. For the z test of independent proportions there were significant differences: z = -3.86, p < .001 [95% CI = -.279, -.092]. Women were more likely to want to use short or long-fingered gloves as compared to men.
36.04% of all respondents would pay increased cost for such gloves:10% extra by 25.11% respondents, 25% extra by 11.43% respondents.
The response from all males willing to pay additional cost was 32.98% and from females 43.11%.
CONCLUSIONS: The data indicate that current sterile gloves do not support hand anatomy variations. A high percentage of sterile glove users would want gloves with variable finger lengths if such gloves were available. Better fitting sterile gloves should facilitate the processes of wound management.
P22.
Purpose: This study examined serum metabolic profiles associated with healing versus non-healing in chronic venous leg ulcers (CVLUs) over time in a cohort of older adults.
Methods: Serum samples (N=60) from an ongoing R01 study (R01NR016986) were collected and stored in the biorepository and then analyzed at the Southeast Center for Integrated Metabolomics (SECIM) at the University of Florida. An LC-MS untargeted metabolomics approach using high-resolution mass spectrometry (HRMS) combined with ultra-high-pressure liquid chromatography (UHPLC) was utilized to examine metabolites of 30 individuals (>50 years of age) with CVLUs at two timepoints (T1 = baseline and T2 = 4 or 8 weeks). There were 20 participants in group 1 (non-healed CVLUs) and 10 participants in group 2 (healed CVLUs). Data from positive and negative ion modes were separately subjected to statistical analyses. An ANOVA test statistic was used to examine significant changes in metabolites over time. Multivariate analysis included PCA and PLS-DA to identify significant metabolites.
Summary of Results: There were 2109 features detected from the positive mode (POS) and 2889 features in the negative mode (NEG). Identified metabolites (N =25), including Octanoylcarnitine (POS), Salicylamide (POS), Linoleic Acid (NEG), and Arachidonic Acid (NEG), significantly changed over time. The remaining (N = 230) significant metabolites are detectable; however, the chemical structure has not been identified and therefore are identified numerically. PLS-DA results revealed 54 (POS) and 42 (NEG) features were significant with a VIP score of > 2. Among the top 15 significant features in the positive and negative data sets, only 2 were known metabolites, 2-Methylglutaric Acid and Octanoylcarnitine.
Conclusion: Our data indicate LC-MS is a feasible approach for detecting significant metabolites present in serum samples of individuals with CVLUs. Significant changes in metabolites were detected, as well as significant metabolites in positive and negative data sets. Many significant metabolites are not yet identified. The utility of metabolomics in wound science is contingent upon continuing to identify and define the uncharacterized metabolites. Additional studies with larger cohorts are needed to test these concepts independently, improve understanding of healing trajectories, and develop targeted interventions for managing and treating CVLUs.
P23.
Background: Women and adolescents who undergo pelvic radiation and/or surgery often face lifelong sequelae from resulting vaginal fibrosis. Unfortunately, there are few treatment options due to the lack of vaginal fibrosis research. Our goal is to develop a reproducible vaginal fibrosis model in mice to fundamentally understand potential healing mechanisms in order to ultimately evaluate treatment and prevention options for alleviating associated symptoms for the almost 200,000 women affected.
Methods: Six to seven-week-old C57Bl/6J mice were anesthetized and instilled vaginally with normal saline (control) or 2.5U/kg bleomycin following physical trauma to induce epithelial disruption using a 0.079” diameter brush (B+ED). This was repeated 5 times over 10 days, and mice were euthanized 1 day, 3 weeks, and 6 weeks after the last instillation (n=3-7). Vaginal tissue was harvested for trichrome staining to evaluate collagen content and localization as well as flash frozen for qPCR analysis. Statistical significance was determined by t-test between control and B+ED at each time point.
Results: One day after the last instillation, there was no difference between total positive collagen staining within the vaginal submucosa between control and B+ED mice. Similarly, after 6 weeks of recovery, no difference in total collagen between control and B+ED vaginal tissue was found. However, after 3 weeks there was significantly more collagen in B+ED vaginal tissue compared to control. Additionally at 3 weeks after the last instillation, using pooled samples and a qPCR fibrosis array, we found increased Acta2, Col1a2, Col3a1, Timp3, and Timp4, as well as a decrease in Mmp13, Mmp8, and Mmp9 when comparing B+ED to control vaginal tissue.
Conclusion: Together our data suggest that epithelial disruption accompanied by bleomycin vaginal instillation results in established fibrosis at 3 weeks after the final regimen, likely through a coordinated action of increased synthesis and decreased degradation of collagen. However, the murine vagina has the ability to recover by 6 weeks. This provides us with a valuable tool to elucidate mechanisms of vaginal fibrosis and potential prevention and treatments for the many women suffering from vaginal fibrosis.
P24.
Background: Inappropriate scarring can result in significant morbidity that negatively impacts physical, functional, and psychosocial outcomes, particularly of the face. There remains a need to study how scarring perception varies among ethnic groups as well as scar impact on broader quality-of-life themes such as career and sexual well-being.
The objective of this study is to evaluate Caucasian and Asian patients’ perception of the impact of their facial scars on symptoms, appearance, psychosocial health, career, and sexual well-being using the SCAR-Q and the CS scales.
Method: A total of 149 facial surgery patients from five providers completed the SCAR-Q, and Career/Sexual Well-Being (CS) scales via phone or email. A higher score on both assessments indicates a more positive patient perception.
Results: Of the respondents, 50.3% were Asian and 49.7% were Caucasian. Patients underwent blepharoplasty (n=56), rhinoplasty (n=21), eyelid revision (n=19), face lift (n=18), Moh’s surgery (n=7), chin augmentation (n=6), craniotomy (n=6), and other procedures (n=16). Caucasian patients scored significantly better on the SCAR-Q (mean rank=86 vs. 64), appearance (mean rank=89 vs. 61), psychosocial (mean rank=83 vs. 67), and CS (mean rank=93 vs. 58) scales than Asian patients (P=.003, P<.001, P=.017, and P<.001 respectively) (Figure 1). There was a significant correlation between duration after surgery and symptoms scores for Asian (r=0.326, P=.004) and Caucasian patients (r=0.319, P=.011).
Conclusions: Asian patients are more likely to have more negative perceptions of their scar’s appearance, symptoms, psychosocial impact, career impact, and sexual well-being impact than Caucasian patients. Scar symptoms may improve over time while appearance, psychosocial, career, and sexual well-being impact may not. This study highlights the need to improve scar follow-up care, counseling, or other enhancement measures for patients of differing ethnicities.
P25.
Background
Chest keloids often converged into a large lesion on the chest in some patients. Such keloids often lead to obstacles to excision and reconstruction. We describe our surgical treatment using a half keystone flap. It was subsequently followed by immediate 1000cGy radiation therapy.
Methods
We prospectively gathered patients with chest keloids between May 2021 and Dec 2021.
Also, we analyzed our data from March 2017 and Dec 2020 retrospectively without radiation therapy.
Results
Of the 20 patients, Fifteen patients thought that the esthetic result was good (75%), and five patients thought the result was acceptable (25%). None patient was dissatisfied. (figure.1)
Conclusion
Half keystone flaps are effective surgical methods for managing large chest keloids. It can offer enough skin flap coverage for keloid wound resurfacing with a stable blood supply to assure satisfactory results.
P26.
P27.
P28.
Introduction:
Distal third lower extremity wounds caused by trauma, arterial insufficiency, or necrotizing soft tissue infections are difficult to heal, and often result in amputations. Plastic surgeons often refer to this zone as “no man’s land”, in reference to the paucity of local flap options and the inability to successfully utilize free tissue transfers in the setting of comorbidities or optimized arterial insufficiency that remains incapable of supporting a free flap. We present an underutilized local flap for limb salvage in complex distal third leg and ankle wounds that would typically require amputation.
Methods:
A retrospective chart review of a single surgeon’s adipo-fascial turnover flaps for lower extremity limb salvage were reviewed for demographic data, wound etiology, and outcome. Patients who had been recommended for amputation by a surgical specialist and were not a candidate for free tissue transfer reconstruction were included in the review.
Results:
Seven patients aged 37-78 (mean 52) were included. The etiology of the wounds included three wounds from trauma, three from arterial insufficiency, and one from necrotizing infection. Three patients had laterally based sural perforators and four had medially based posterior tibial perforators. Donor sites were closed with autologous full thickness skin grafting. All patients had complete wound healing (2 patients required secondary operations for flap ischemia and debridement with flap advancement) without need for amputation. All patients were able to successfully ambulate postoperatively.
Conclusion:
Complex distal third lower extremity and ankle wounds with exposed bone and tendons are challenging to heal by secondary intention. As a result, free tissue transfer has been the standard flap reconstruction for this anatomical region. In patients that are unable to have free tissue transfer, flap reconstruction with an adipo-fascial turnover flap should be considered prior to an amputation.
P29.
Temporal hollowing deformity (THD) is a contour irregularity in the frontotemporal region, which is a common complication following surgical dissection of the temporal region or use of the coronal approach for neurosurgery. THD is characterized by a concave contour within the pterional region, along the temporal fossa and posterior to the lateral orbital rim, which results in facial asymmetry in the frontal view Here, we present our clinical experience of correction of THD using serratus anterior (SA) muscle and fascia free flaps.
Between March 2016 and December 2018, 13 patients presenting with THD were treated with SA free flap. The mean age of the patients was 47.8 years. The patients received craniectomy due to subarachnoid hemorrhage, epidural hematoma, or brain tumor. All patient underwent cranioplasty with autologous bone, poly-methyl-methacrylate, or titanium mesh.
On average, the correction of THD was performed 17 months (range; 12 – 24 months) after cranioplasty. The SA muscle and fascia flap size ranged from 5 x 5 cm to 10 x 8 cm. The operation time was 107.3 minutes (range; 75 – 150 minutes). All of the flaps survived without complications. The mean follow-up duration was 20.3 months (range; 12 – 48 months).
The goal of THD correction is to permanently restore aesthetic form and symmetry. Vascularized free tissue transfer provides sufficient soft tissue volume to correct THD permanently, and the robust blood supply ensures volume augmentation effect even in an irradiated or contaminated surgical field. The disadvantages of free tissue transfer include its complexity, long surgical time and hospitalization period, and donor site morbidity. For correction of THD, the SA muscle and fascia flap is among the best candidates to permanently restore aesthetic form and symmetry.
P30.
Background: International guidelines advise use of supplemental L-arginine as part of specialized nutrition for partial or full thickness pressure injury in malnourished or at-risk adults.1 A 5-10 day protocol of high protein immunonutrition (HPIM) containing supplemental L-arginine, n-3 fatty acids and dietary nucleotides has been repeatedly demonstrated to help reduce infection and length of stay after surgery.2 Since little is known about HPIM in chronic wounds, we evaluated a 30-day course of HPIM in a malnourished adult with a full thickness chronic leg ulcer requiring limb salvage surgery.
Methods/Case Description: A 57-year-old white male had a 4-month history of a worsening right lower leg ulcer, initiated by minor trauma, but 34 cm3 in size on his first visit, with extensive exposure of tendon. Biopsy confirmed pyoderma gangrenosum; treated with high dose oral prednisone (60 mg daily), and surgery planned.
Physical exam identified muscle wasting and patient reported a 15% weight loss of usual body weight in the past month. A Mini-Nutritional Assessment3 score of 7 also indicated a malnourished patient. Clinicians stressed the importance of HPIM and after a taste test, he committed to consuming 2 HPIM cartons/day for 30 days (400 calories, 36 grams of protein and 8.4 g L-arginine daily). He was provided with a 1-month supply of HPIM samples, a record keeper, flavoring tips and a list of high protein foods. After HPIM samples were exhausted, patient utilized standard oral nutritional supplements for additional calories and protein for 3 weeks prior to surgery.
Results: Compliance with HPIM was confirmed at follow-up visits. Within one week of starting HPIM, the wound demonstrated increased granulation tissue, and within one month patient had gained 14 pounds. Tendon removal and successful surgical skin graft closure took place after approximately two months of nutrition intervention with healing by primary intention.
Conclusion: Despite the use of high dose steroids and pre-existing malnutrition, a highly motivated patient and health care providers committed to nutritional intervention resulted in successful limb salvage surgery including a skin graft. Clinic taste test, record keeping and removing barriers such as cost facilitated the success of specialized nutritional supplementation.
1. EPUAP, NPIAP & PPPIA. Quick Reference Guide. Emily Haesler (Ed.). EPUAP/NPIAP/PPPIA: 2019.
2. Adiamah A et al. Ann Surg 2019;270(2): 247-256.
3. Kaiser MJ et al. J Nutr Health Aging 2009;13: 782-788.
P31.
Background: A 5-10 day protocol of high protein immunonutrition (HPIM) containing supplemental L-arginine, n-3 fatty acids and dietary nucleotides has been repeatedly demonstrated to help reduce infection and length of stay after surgery.1 Since little is known about HPIM in chronic wounds, we evaluated a 30 -day course of HPIM in a malnourished adult with a severe ischemic foot injury requiring limb salvage surgery.
Methods/Case Description: A 34-year-old previously healthy African American female had a 21-day stay in intensive care for sepsis with hypotension and disseminated intravascular coagulopathy (DIC) causing bilateral foot ischemia. Three months later she presented to the wound center with a 15 pound weight loss, a right transmetatarsal amputation (TMA) with a non-healing area (1 cm3), and 2 ischemic ulcerations of the left plantar and lateral foot with exposed bone (70 cm3, 8 cm3). Skin perfusion pressure demonstrated that perfusion of the lateral foot was insufficient for healing (23 mmHg) and surgery was scheduled.
A Mini Nutrition Assessment2 score of 7 indicated a malnourished patient. Clinicians stressed the importance of HPIM and after a taste test, she committed to consuming 2 HPIM cartons/day for 30 days (400 calories, 36 grams of protein and 8.4 g L-arginine daily). She was provided with a 1-month supply of HPIM samples, a record keeper, flavoring tips and a list of high protein foods.
Results: Compliance with HPIM was confirmed at follow-up visits. Within two weeks of starting HPIM, the TMA site closed and granulation tissue was noted on left foot wounds despite tissue hypoxia. Approximately 1 week after completing HIPM, she underwent an extensive foot resection of infected bone and ischemic tissue which was closed primarily and healed without difficulty. She was ambulating 12 weeks later.
Conclusion: A highly motivated patient and health care providers committed to nutritional intervention with HPIM resulted in successful limb salvage surgery despite preoperative malnutrition and an existing non-healing surgical wound. Clinic taste test, record keeping and removing barriers such as cost facilitated the success of specialized nutritional supplementation.
1. Adiamah A et al. Ann Surg 2019;270(2): 247-256.
2. Kaiser MJ et al. J Nutr Health Aging 2009;13: 782-788.
P32.
We have studied daily jet lavage irrigation in the nursing home setting for the past three years with excellent safety and wound cleansing compared to the standard of care. This report discusses the addition of antiseptic as a low pressure irrigated fluid.
Methods:
A 72-year-old male has a large difficult stage 4 pelvic pressure injury over the sacrum for the past 8 years that has not responded to standard of care treatment. After surgical debridement, he was entered into our investigational study where the wound was treated daily (ave. 5 days/week) with low pressure jet lavage irrigation with 3 liters of fluid (IRB #6066, Stirling Investigational Review Board, Atlanta, Ga). After 13 months treatment, we noticed that wound cleansing was not complete with our protocol. We added squeeze bottle irrigation with modified sodium hypochlorite getting the complete cleansing we sought. The IRB reviewed use of the antiseptic and approved the application through the jet lavage irrigator. We have now done 120 daily treatments over 6 months and assessed a small series of exams. After a long weekend of standard care with simple saline soak gauze dressings, we typically found a heavy bacterial growth (>log 4 colony forming units/gram of tissue) of three different bacteria, Acinetobacter baumannii, Pseudomonas aeruginosa, and group B Streptococcus.
Autofluorescence imaging was done after treatment on Monday with 72 hours interval from prior treatment.
Results:
After seven ‘long weekends’ three-day intervals, autofluorescence imaging revealed completely removed detectable bacteria by our method (Sensitivity: <log 2 colony forming units/gram of tissue). The wound appeared ‘black’ with the 405 NM violet light. We have identified no complications or concerns with this experience.
Conclusions:
This study confirms that jet lavage irrigation remains an important method for early wound bed preparation and bioburden debris removal. In grossly contaminated wounds, irrigation may not remove all the bacteria. Irrigating antiseptic solution under low pressure under 15 PSI has proven to be a valuable adjunct for this process.
P33.
The purpose of this case report is to examine the benefits of “holistic” wound care in reducing the cost of invasive surgeries and amputations. Our patient is a 69-year-old diabetic man who presented to our wound center with a 2-month-old, painful, draining, necrotic, malodorous wound on the back of his ankle, with an exposed Achilles tendon. The patient did not know how the wound started. He was very upset and verbalized with staff about not having received appropriate care so far for his wound. He was diagnosed with mixed arterial-venous disease by a vascular surgeon.
With his medical comorbidities, our patient was at risk for severe infection and amputation. A “holistic” plan of care was established, with all wound care provided at the wound center with close monitoring. The frequency of wound center visits was 3x/week with the same team, physician visit once a week, and wound nurse twice a week. Wound care included standard care with cleaning the wound and skin with Hibiclens, topical cadexomer iodine, multilayer compression for edema control, and serial debridements. This frequency of visits was to keep the wound clean and effectively compress edema and drainage control. The patient kept the dressing and bandages on between visits. He was provided ongoing education on his condition, progress of the ulcer, and risks of wound failure. The wound has had a progressive increase in healthy granulation covering all of the Achilles tendon, new epithelization, wound contraction, and no pain. His wound is expected to heal completely. He is also more compliant and satisfied with his medical treatment and has a more positive outlook towards his recovery.
This case is small, but the magnitude of its significance is massive. It points to our ability to use cost-effective treatment protocols on wound management before it can progress to the point that requires expansive surgical procedures. Standard practice at wound centers is multiple providers for the same patient, combining wound center visits with home care, long gaps between follow-ups, resulting in wounds taking a long time to heal or having poor outcomes. What we provided is a novel concept of providing continuity and consistency of care that drives compliance, close monitoring, timely adjustments in care of the wound, ultimately reducing time to heal without costly surgical procedures.
P34.
Background: Acellular dermal matrix (ADM) is effective for tissue regeneration and wound healing. This study was performed to compare the wound size reduction rate, epithelization rate, growth of granulation tissue, complete wound healing rate, and safety between patients receiving ADM therapy and standard wound care.
Methods: The inclusion criterion was chronic non-healing wounds, ranging from full-thickness skin defects to bone exposure, measuring > 4 cm2 that failed to heal following a minimum of 3 weeks of conservative care prior to the study. Following a 7 day screening period, patients were randomized to receive either paste-type ADM therapy or standard wound care. The wound was assessed at 0, 1, 2, 4, 8, and 12 weeks.
Results: A total of 86 patients were enrolled in the study. The wounds showed a continuous and constant reduction in size from week 1, and the wound size reduction was significantly greater compared to the control group from week 2 until the study endpoint (week 12). Granulation tissue formation was observed in 36 of 38 wounds (94.7%), and full epithelization in 34 of 38 wounds (89.5%), in the study group. Wound healing was achieved in 29 of 38 wounds (76.3%) in the study group.
Conclusions: Paste-type ADM is a useful option for wound healing and can be applied efficiently and safely for advanced wound care.
P35.
Background: Venous leg ulcers (VLUs) account for 70–90% of ulcers found in the lower leg, and they affect 2 million persons annually. VLUs have high rates of non-healing and progress to chronic wounds. The high rates of non-healing wounds are associated with multiple morbidities, local and systemic contributing factors. However, comprehensive characteristics including symptoms and molecular behaviors in the complex progression of chronic wounds in VLUs are still elusive. The purpose of this study was to characterize molecular behaviors from wound fluid, biological and psychological factors from patients with CVLUs during 8 weeks of wound debridement.
Methods: Participants(N=76) were recruited from a wound clinic. We collected symptoms and would fluid at baseline, week 2, 4, 6, and 8. Pain was measured by Toronto Wound Assessment. Fatigue was measured by Brief Fatigue Inventory. Wound fluid was collected by swabbing. The total activity of MMPs was measured by the change in fluorescence per unit time and reported in units of MMP-9 equivalents. Wound fluid CRP was measured by ELISA. Bayesian methods were employed to examine the strength of association among variables.
Results: Among 76 participants, 38 (54%) were male, 62 (87%) were white, and the mean age was 71.8 (SD= 10.1) years. A total of 41 patients at week 8, 32 (78%) of participants had non-healed wounds. Bayes Factor (BF) indicated that wound areas were associated with CRP (BF=11.2) and MMPs (BF=2.5). Fatigue was associated with wound areas (BF=13), CRP(BF=4) and biweekly changes of MMPs (BF=5). Pain was associated with CRP (BF=13) and biweekly changes of CRP (BF=17).
Conclusion: Evidence supports the reduction in wound area over time, and higher wound CRP is associated with larger areas of wounds. Advanced age, having comorbidities, and higher CRP and MMPs in wound fluid associated with non-healed wounds. Patients with higher wound fluid CRP tend to experience more pain. Younger patients tend to experience more pain and less fatigue. Although there is no support for wound CRP or wound MMPs moderating the change in area over time, comprehensive assessment including molecular changes from wound fluid, symptoms such as pain, and fatigue may help promote the wound healing of CVLUs.
P36.
Background: Various types of flaps are widely utilized as reconstructive options for patients with soft tissue defects. However, monitoring of the flaps still require a large amount of time and effort. The aim of this study was to evaluate the efficacy and safety of novel monitoring procedure using negative pressure wound therapy (NPWT) immediately after the flap operations especially in Diabetic Foot (DF) patients.
Methods: A retrospective analysis was performed on DF patients who underwent free flaps and perforator flaps from March 2020 to August 2021. The flaps were managed by either novel NPWT method or conventional dressing. Among NPWT group, computed tomography (CT) angiography was performed in randomly selected five flaps on the third postoperative day for evaluation of pedicle compression. Statistical analysis was performed between the two groups.
Results: A total of 26 flaps were included in this study. 14 flaps were managed using novel NPWT method and 12 flaps were managed using conventional dressing. There was no statistically significant difference in flap survival rates between the two groups (p = 0.91). The patency of flap pedicles in the NPWT group was confirmed by comparing the CT angiography findings. The estimated total flap monitoring time and cost for 5 days was significantly decreased by the application of the novel NPWT monitoring system.
Conclusion: Through the application of the novel postoperative monitoring system using NPWT, there is efficient evaluation of the flap in diabetic foot patient. Furthermore, safe flap monitoring is possible with the reduced risk of infection by the avoidance of multiple manual dressing performed in the conventional method.
P37.
This study aimed to examine the positive effects of polydeoxyribonucleotide (PDRN) on the wound-healing process in pressure injuries. In this randomized controlled trial, the effects of PDRN were compared over time between an experimental group (n = 11) and a control group (n = 12). The former was administered the same dose of PDRN intramuscularly (1 ampule, 3 mL, 5.625 mg, for 5 days) for 2 weeks and perilesionally (1 ampule, 3 mL, 5.625 mg, twice a week) for 4 weeks. The primary endpoint for determining efficacy was wound healing in the pressure injuries, which was reflected by the wound surface area determined using VISITRAK Digital (Smith & Nephew, Largo, FL). The secondary endpoint was the pressure ulcer scale for healing score, determined using pressure ulcer scale for healing (PUSH Tool 3.0 developed by the National Pressure Ulcer Advisory Panel). After the 4-week treatment period, PDRN therapy was found to significantly reduce the wound size and PUSH score, without adverse effect during the treatment. The findings indicate that PDRN can positively modify the wound healing process in pressure injuries, and its use could improve the clinical outcomes of patients and lower the need for additional therapies or hospital stay
P38.
Chronic ulcers present a costly challenge to healthcare, and for patients, an increased risk of hospitalization, and poor quality of life. Though non-healing wounds may differ in etiology, a unifying feature is infection. Pseudomonas aeruginosa (PA), an opportunistic pathogen frequently identified in chronic wounds, evades the host immune system and resists antibiotic treatment by forming robust biofilms. Published studies show that the growth of some bacterial species can be modulated by catecholamines and mammalian adrenergic receptor (AR) antagonists. In this study, liquid cultures and biofilms of Pseudomonas aeruginosa strain PAO1 were treated with norepinephrine or epinephrine and timolol, a beta AR antagonist. Optical densities of liquid cultures and stained biofilms, as well as biomass and gene expression of biofilms were compared with untreated controls. In liquid culture grown for 24 hours, norepinephrine (NE) and epinephrine (EPI) increased OD of PA by 87% and 47% (n=3, 6), and timolol (TIM) reduced the OD of NE-treated cultures by 15% (n=2) (p<0.05). Static biofilms grown for 72 hours with NE and EPI had 2.5 and 3 times more biomass than untreated controls, and TIM reduced the biomass of EPI-treated groups by 28% (n=10, p<0.05). Imaging of PAO1 biofilms that were EPI-treated were found to be an average of 14% thicker than untreated controls for all timepoints, while treatment with TIM reduced thickness an average of 12% in all timepoints. Catecholamine-treated biofilms produced significantly more pyocyanin and pyoverdine than untreated biofilms (N=3, p<0.05). Interestingly, addition of TIM reduced gene expression for a number of genes associated with pyoverdine production, as well as others involved in biofilm formation and virulence (N=3, p<0.05). TIM treatment of human ex vivo skin wounded and infected with PAO1 decreased CFU/mg by two orders of magnitude (p<0.05). These findings demonstrate that growth of this common wound pathogen can be modulated by the catecholamines epinephrine and norepinephrine, which are present in wounds. However, the findings that these growth and biofilm effects can be partially reversed by the beta AR antagonist timolol, suggest a potential therapeutic role of timolol for chronic wounds.
P39.
Background: The molecular hypotheses for wound chronicity have evolved from a lack of pro-healing growth factors, to tissue destruction by host-derived proteases, and now the bacterial biofilm hypothesis is posited to unify these hypotheses. The common idea is that wounds get stuck in a prolonged inflammatory phase. Much of current research for product development is focused on treating biofilms or reducing bioburdens in order to help the wound “turn the corner”. An analysis of healing, viable biofilms, and inflammation markers in several studies has begun to cast doubt on the prolonged inflammation hypothesis; at least as it is currently formulated.
Methods: A combined post hocanalysis of clinical trial and clinical study data and literature review of non-human studies. The clinical data include trials and studies with measures of wound healing by area and volume, inflammatory markers such as matrix metalloprotease activity, local and systemic C-reactive protein, total protein, and measures of viable bacterial biofilm.
Results: The non-human studies in experimental animals are fairly clear that an injury in an health animal does not permit the formation of a biofilm. Animal models require substantial immune modulation such as induced neutropenia preceding wound inoculation, otherwise the infections are cleared prior to being able to form biofilms. In the human studies, a comparison of a given timepoint’s bioburden and its levels of inflammatory markers does not reveal a strong correlation.
Conclusions: Biofilms are likely inflammatory in healthy patients, which is why otherwise healthy people do not get them. In otherwise healthy individuals with high trauma, immune saturation/depletion can provide a immunosuppressed window wherein biofilms can form. In the population of patients with chronic wounds, both the biofilms and lack of healing might be symptoms of an attenuated immune response.
P40.
Diabetic foot ulcers (DFU) are one of the most prevalent types of chronic wounds and are associated with a high morbidity, amputations, and mortality. DFUs are characterized by a deregulated immune response with decreased neutrophils due to loss of the transcription factor, FOXM1. Diabetes primes neutrophils to form neutrophil extracellular traps (NETs) that contribute to tissue damage and impaired healing. However, the role of FOXM1 in priming diabetic neutrophils to undergo NET formation remains unknown. We utilized a multi-disciplinary approach of genomics, murine and human models to investigate the role of FOXM1 in regulating NET formation during diabetic wound healing. Here, we found that FOXM1 regulates reactive oxygen species (ROS) levels in neutrophils and inhibition of FOXM1 resulted in increased ROS levels leading to NET formation. Next generation sequencing revealed TREM1, an amplifier of the inflammatory response highly expressed in neutrophils, as an upstream regulator of FOXM1. Activation of TREM1 reversed effects of diabetes and promoted wound healing in vivo. Moreover, we found that TREM1 expression correlated with clinical healing outcomes of DFUs, indicating TREM1 to be a useful biomarker and potential therapeutic target. Our data underscore TREM1/FOXM1 pathway as previously not reported regulator of NET formation during diabetic wound healing, revealing potential diagnostic and therapeutic targets that may promote healing in DFUs.
