Abstract 65: The Effect of Padded Adhesive Dressings and Body Position on Sacral Interface Pressure

Abstract

PURPOSE: Padded adhesive bandages have been increasingly used in the operating room and in the inpatient setting to reduce the incidence of pressure ulcers. However, whether these bandages truly decrease interface pressure at the sacrum is not known. It was hypothesized that there would be a reduction in sacral peak interface pressure for a supine position, further reduced in 30 degree and seated positions, respectively. METHODS: 40 healthy adult volunteers of both sexes were recruited to this study. Study participants sat on a pressure-sensing mat (CONFORMat™ Tekscan, Boston, USA) in 3 positions for 30 seconds each: 1) Sitting upright with legs off the floor; 2) Supine; 3) Supine with the back resting on a 30 degree wedge. For each position, each participant first wore only thin cotton pants. The measurement was then repeated with a padded adhesive bandage (Mepilex® Gentle Border, Mölnlycke Health Care, Norcross, USA) on the sacrum under the pants. Age, sex, and body mass index (BMI) were collected for all participants. Peak pressures were compared across positions using linear mixed effects modeling. As fixed effects, Mepilex and position were included in the model. Participants, BMI, sex, and age were entered as random effects. Demographic data was analyzed using descriptive statistics. Normality was checked using Wilks-Shapiro testing. P values were obtained by likelihood ratio testing of linear mixed effects models sequentially incorporating factors of interest, with significance at p = 0.05. RESULTS: 20 females and 20 males participated with age 29.6 +/- 9.3 (range 18–60) and BMI 23.4 +/- 3.2 (range 17.9–38.1). After controlling for by-subject variation, age, and sex, BMI did not further account for variability in peak sacral pressure (p = 0.22). Body position accounted for a significant amount of variability among participants when added to the model (p < 0.01). The presence of a padded adhesive dressing itself did not account for further variability after controlling for by-subjects variation, sex, age, BMI, and body (p = 0.17); sacral peak pressure was equivalent between the bare sacrum (mean +/- standard deviation; 229.8 +/- 127.7 mmHg) and padded adhesive dressing conditions (247.8 +/- 147.3 mmHg). Finally, there was no significant interaction between BMI and body position when this was added to the model (p = 0.11). CONCLUSION: This study demonstrated that a padded adhesive bandage did not provide a reduction in interface pressure in any position over the sacrum. Pressure on the sacrum was highest in the supine position and this was not influenced by BMI. If padded bandages provide clinically significant reduction in the incidence of pressure ulcers, then it is not simply through the reduction of interface pressure. Other potential causative factors of hospital acquired pressure ulcers and should be investigated further.