CRITICAL THRESHOLDS FOR CAUSATION OF CUTANEOUS AND SUBCUTANEOUS INJURY IN A PORCINE MODEL: EXPERIMENTAL AND NUMERICAL APPROACHES (PRESSURE ULCERS, BURNS).
Contributors: University of Minnesota.
Published: 1996
Number of pages: 160
Subjects: Engineering, Biomedical.; Health Sciences, Nursing.; Health Sciences, Medicine and Surgery.
Description: The objective of the research was to create animal models to study the etiology and pathophysiology of skin surface wounds. Specifically, an animal model was used to define critical thresholds of applied pressure, applied temperature and duration of application necessary for the formation of pressure ulcers or cutaneous burns using both experimental data and numerical analysis. A porcine model for incision wounds was also developed to study the effects of focal warming on the healing process of incision wounds. For the study for pressure ulcers and burns, twelve metal discs were simultaneously applied on the dorsal aspect of each swine while modulating applied pressure, temperature and application time at each site. In all, seventy different experiments were conducted using different magnitudes of the aforementioned parameters. Histological assessment, along with laser Doppler fluxmetry and color imaging provided the basis for the determination of damage at different tissue levels. Each tissue level was ranked histologically for degree of injury to: the epidermis (tissue necrosis), dermis (hair follicle/apocrine gland damage, vascular damage, nerve/muscle damage, and infiltrate), subcutaneous tissue (infiltrate, vessel damage and compression), and underlying muscle (necrosis and infiltrate). An algebraic fit of experimental data provided equations which were used to predict wound formation for any combination of these parameters. Three-dimensional plots of the data were used to define the critical thresholds for damage within each tissue layer. A porcine incision model was also developed to study the effects of focal warming on wound healing. Tensile wound strength and hydroxyproline assays were used for assessment of healing. It is expected that these models will have widespread utility for use by nursing professionals and biomedical engineers.
Notes: Source: Dissertation Abstracts International, Volume: 57-11, Section: B, page: 7075.

Thesis (PH.D.)--UNIVERSITY OF MINNESOTA, 1996.

School code: 0130.