Effectiveness of Pressure Garment Therapy After Burns

Purpose - To determine the effectiveness of custom-fit pressure garment therapy in the prevention of hypertrophic scarring in healed burns. Background - Approximately one million people are burned each year in the United States. The most devastating outcomes following burns is the ugly, itchy, hypertrophic scar that interferes with work and all other aspects of life. Pressure garment therapy is routinely used to minimize hypertrophic scarring even though there is no scientifically valid data that this therapy is efficacious. Pressure garments are extremely unattractive, expensive and uncomfortable and their use needs to be based upon valid data. Goals and Objectives - The investigators plan to determine the effectiveness of pressure garment therapy in the control of hypertrophic scarring in healed burns. Methods - The I-Scan® device was designed to measure pressure at the body/environment interface and allows clinicians to deal with pressure-related problems for at-risk patients. It has been widely used in rehabilitation medicine but not with burn survivors. The investigators will use this device to measure the pressure at the garment/skin interface. 2) Furthermore, the few studies that have been attempted to determine efficacy have used between subjects designs. Since burn depth is extremely variable from patient to patient and since hypertrophic scarring is greatly influenced by age and race/origin, the between subjects design requires very large numbers of subjects. The investigators will use a within wounds design studying forearm burns and applying pressure to half of the wound and no pressure to the other half. The investigators will then compare hardness, color, thickness and clinical appearance.

Cloth garments designed to apply 17-24 mmHg pressure to the 1/2 the burn wound and <5 mmHg to the other half, to be worn 23 hours per day until wounds mature, approximately 12 months

Pressure measurements were obtained at the scar/garment interface using the I-ScanTM System (Tekscan, Inc., South Boston, MA). The device was calibrated and the pressure determined in mmHg. Pressure measurements were obtained by a therapist not involved in the care of the patient, who was trained in the use of the device. Therefore pressure ''dose'' was measured directly. Values reported are averaged over indicated visits.

A single Rex Durometer Hand Model 1600, Type 00, without a foot attachment (Rex Gauge Company Inc., Glenview, IL) was used to measure scar hardness throughout the study. This device measures hardness of light foams, sponge rubber gels, and animal tissue in "durometer units" (range 0=soft, 100=hard). Measurements were obtained with the person in the sitting position with the forearm supported in a horizontal position on a desk and the shoulder adducted. The area of interest was triangulated and measurements obtained at the corners were averaged; the sides of the triangle were 3-5 cm.

A Chromameter Minolta CR-300 (Konica Minolta, Ramsey, NJ) measured skin color. Skin surface illuminated by pulsed xenon arc lamp. Light reflected perpendicular to surface collected for a tri-stimulus color analysis. One measurement consisted of three flashes of illumination in order to obtain a mean value. Measurement values are in the L*a*b* color space was described by The Commission Internationale de I'Eclairage (CIE)(L=brightness [100=white,0=black], a=red-green[red=60,green=-60], b=yellow-blue[yellow=60,blue=-60])

Scar thickness in millimeters was obtained with high-frequency ultrasonography in the Department of Radiology. Several machines and probes were used over the years each with accuracy to 0.5 mm. The area of interest was triangulated and measurements obtained at the corners were averaged; the sides of the triangle were 3-5 cm.

Photographs of wounds showed final cosmetic result. The two compression areas for each photograph were labeled distal (D) and proximal (P). We asked 11 experts (blinded as to the compression of the rated zones) to judge which zone (D or P) had the better cosmetic appearance or whether there was no difference. Votes were tallied according to the unblinded compression zone (i.e., high/normal and low). We report number of participants for which the rating experts all agreed or did not all agree (i.e., voted the other zone or "no difference") that the indicated zone had the better appearance.

The patients were asked to complete a compliance form indicating how many hours the garment was worn each day.

Inclusion Criteria: Treated from time of burn at the University of Washington Burn Center during the first two years of the grant period Burns covering the majority of the forearm that healed spontaneously in three or more weeks. Patients will be entered into the study within 4 weeks of injury. Age 7-65 years. Patients younger than 7 years will be excluded given the cooperation required during follow-up evaluations. Patients over 65 years will be excluded since the incidence of hypertrophic scarring in persons over 65 is too low to warrant pressure garment trials. Patients of any race, ethnicity, or skin color. Informed, written consent in accord with the rules of the Human Subjects Committee of the University of Washington and the Health Insurance Portability and Accountability Act (HIPAA). Exclusion Criteria: Incarcerated patients Homeless patients Patients with substance abuse Patients with psychiatric diagnosis Patients unavailable to return regularly for follow-up evaluations

Engrav LH, Heimbach DM, Rivara FP, Moore ML, Wang J, Carrougher GJ, Costa B, Numhom S, Calderon J, Gibran NS. 12-Year within-wound study of the effectiveness of custom pressure garment therapy. Burns. 2010 Nov;36(7):975-83. doi: 10.1016/j.burns.2010.04.014. Epub 2010 Jul 1. Erratum In: Burns. 2011 Jun;37(4):725.