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A Translational Animal Model for Scar Compression Therapy Using an Automated Pressure Delivery System.

Alkhalil A, Tejiram S, Travis TE, Prindeze NJ, Carney BC, Moffatt LT, Johnson LS, Ramella-Roman J, Shupp JW - Eplasty (2015)

Bottom Line: Gross scar examination by the Vancouver Scar Scale showed significant and sustained (>4 weeks) improvement in pressure-treated scars (P < .05).Histological examination of pressure-treated scars showed a significant decrease in dermal thickness compared with other groups (P < .05).Cellular quantification showed differential changes among treatment groups.

View Article: PubMed Central - PubMed

Affiliation: Firefighters' Burn and Surgical Research Laboratory, MedStar Health Research Institute, Washington, DC.

ABSTRACT

Background: Pressure therapy has been used to prevent and treat hypertrophic scars following cutaneous injury despite the limited understanding of its mechanism of action and lack of established animal model to optimize its usage.

Objectives: The aim of this work was to test and characterize a novel automated pressure delivery system designed to deliver steady and controllable pressure in a red Duroc swine hypertrophic scar model.

Methods: Excisional wounds were created by dermatome on 6 red Duroc pigs and allowed to scar while assessed weekly via gross visual inspection, laser Doppler imaging, and biopsy. A portable novel automated pressure delivery system was mounted on developing scars (n = 6) for 2 weeks.

Results: The device maintained a pressure range of 30 ± 4 mm Hg for more than 90% of the 2-week treatment period. Pressure readings outside this designated range were attributed to normal animal behavior and responses to healing progression. Gross scar examination by the Vancouver Scar Scale showed significant and sustained (>4 weeks) improvement in pressure-treated scars (P < .05). Histological examination of pressure-treated scars showed a significant decrease in dermal thickness compared with other groups (P < .05). Pressure-treated scars also showed increased perfusion by laser Doppler imaging during the treatment period compared with sham-treated and untreated scars (P < .05). Cellular quantification showed differential changes among treatment groups.

Conclusion: These results illustrate the applications of this technology in hypertrophic scar Duroc swine model and the evaluation and optimization of pressure therapy in wound-healing and hypertrophic scar management.

No MeSH data available.


Related in: MedlinePlus

Analysis of pressure recordings from the pressure delivery system throughout the treatment period. Condensed plot of all pressure values recorded during the 14 days of pressure treatment (a) distribution of pressure values during pressure application (b). Note the cyclical distribution of the out-of-range pressure values that coincides with the number of days and activity periods of the animal (a). Distribution of abnormal pressure values showed higher frequency on the high side of pressure values. The frequency and intensity of abnormal pressure values show an increasing trend as the animal wound healing progresses and animals recover from automated pressure delivery system mounting procedure.
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Figure 3: Analysis of pressure recordings from the pressure delivery system throughout the treatment period. Condensed plot of all pressure values recorded during the 14 days of pressure treatment (a) distribution of pressure values during pressure application (b). Note the cyclical distribution of the out-of-range pressure values that coincides with the number of days and activity periods of the animal (a). Distribution of abnormal pressure values showed higher frequency on the high side of pressure values. The frequency and intensity of abnormal pressure values show an increasing trend as the animal wound healing progresses and animals recover from automated pressure delivery system mounting procedure.

Mentions: Pressure recordings for each device were analyzed to evaluate the performance of the APDS. The data showed that all APDS devices maintained a targeted pressure level of 30 ± 4 mm Hg for more than 90% of the total pressure application duration. The variations in pressure outside of the targeted pressure range accounted for about 9% to 10% of the total pressure application time (Fig 3). These variations mostly ranged between 22–26 and 34–38 mm Hg and were transient, underscoring the rapid response of the system in correcting pressure changes caused by animal activity (Table 4). Out-of-range pressure incidents were more frequent above the desired range than below it at a ratio of approximately 5:1, suggesting that animal behavior accounted for pressure fluctuations rather than mechanical APDS deficiencies. Pressure readings greater than the targeted pressure range accounted for only 8.8% of all pressure readings, and readings exceeding 40 mm Hg only accounted for 2% of all readings.


A Translational Animal Model for Scar Compression Therapy Using an Automated Pressure Delivery System.

Alkhalil A, Tejiram S, Travis TE, Prindeze NJ, Carney BC, Moffatt LT, Johnson LS, Ramella-Roman J, Shupp JW - Eplasty (2015)

Analysis of pressure recordings from the pressure delivery system throughout the treatment period. Condensed plot of all pressure values recorded during the 14 days of pressure treatment (a) distribution of pressure values during pressure application (b). Note the cyclical distribution of the out-of-range pressure values that coincides with the number of days and activity periods of the animal (a). Distribution of abnormal pressure values showed higher frequency on the high side of pressure values. The frequency and intensity of abnormal pressure values show an increasing trend as the animal wound healing progresses and animals recover from automated pressure delivery system mounting procedure.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492193&req=5

Figure 3: Analysis of pressure recordings from the pressure delivery system throughout the treatment period. Condensed plot of all pressure values recorded during the 14 days of pressure treatment (a) distribution of pressure values during pressure application (b). Note the cyclical distribution of the out-of-range pressure values that coincides with the number of days and activity periods of the animal (a). Distribution of abnormal pressure values showed higher frequency on the high side of pressure values. The frequency and intensity of abnormal pressure values show an increasing trend as the animal wound healing progresses and animals recover from automated pressure delivery system mounting procedure.
Mentions: Pressure recordings for each device were analyzed to evaluate the performance of the APDS. The data showed that all APDS devices maintained a targeted pressure level of 30 ± 4 mm Hg for more than 90% of the total pressure application duration. The variations in pressure outside of the targeted pressure range accounted for about 9% to 10% of the total pressure application time (Fig 3). These variations mostly ranged between 22–26 and 34–38 mm Hg and were transient, underscoring the rapid response of the system in correcting pressure changes caused by animal activity (Table 4). Out-of-range pressure incidents were more frequent above the desired range than below it at a ratio of approximately 5:1, suggesting that animal behavior accounted for pressure fluctuations rather than mechanical APDS deficiencies. Pressure readings greater than the targeted pressure range accounted for only 8.8% of all pressure readings, and readings exceeding 40 mm Hg only accounted for 2% of all readings.

Bottom Line: Gross scar examination by the Vancouver Scar Scale showed significant and sustained (>4 weeks) improvement in pressure-treated scars (P < .05).Histological examination of pressure-treated scars showed a significant decrease in dermal thickness compared with other groups (P < .05).Cellular quantification showed differential changes among treatment groups.

View Article: PubMed Central - PubMed

Affiliation: Firefighters' Burn and Surgical Research Laboratory, MedStar Health Research Institute, Washington, DC.

ABSTRACT

Background: Pressure therapy has been used to prevent and treat hypertrophic scars following cutaneous injury despite the limited understanding of its mechanism of action and lack of established animal model to optimize its usage.

Objectives: The aim of this work was to test and characterize a novel automated pressure delivery system designed to deliver steady and controllable pressure in a red Duroc swine hypertrophic scar model.

Methods: Excisional wounds were created by dermatome on 6 red Duroc pigs and allowed to scar while assessed weekly via gross visual inspection, laser Doppler imaging, and biopsy. A portable novel automated pressure delivery system was mounted on developing scars (n = 6) for 2 weeks.

Results: The device maintained a pressure range of 30 ± 4 mm Hg for more than 90% of the 2-week treatment period. Pressure readings outside this designated range were attributed to normal animal behavior and responses to healing progression. Gross scar examination by the Vancouver Scar Scale showed significant and sustained (>4 weeks) improvement in pressure-treated scars (P < .05). Histological examination of pressure-treated scars showed a significant decrease in dermal thickness compared with other groups (P < .05). Pressure-treated scars also showed increased perfusion by laser Doppler imaging during the treatment period compared with sham-treated and untreated scars (P < .05). Cellular quantification showed differential changes among treatment groups.

Conclusion: These results illustrate the applications of this technology in hypertrophic scar Duroc swine model and the evaluation and optimization of pressure therapy in wound-healing and hypertrophic scar management.

No MeSH data available.


Related in: MedlinePlus