A comparison of two pressure-relieving devices on the prevention of heel pressure ulcers

The effectiveness of hospital pillows versus a commercial heel elevation device (the Foot Waffle [EHOB incorporated]) in preventing heel pressure ulcers was examined using an experimental balanced factorial design with repeated measures on 52 patients (ages 27 to 90) in randomized groups. Heel interface pressures were taken with patients in supine and right lateral tilt positions. Logistic regression demonstrated a statistically significant difference between interface pressures on left and right heels (p = .004) and a trend toward significance between the pillow and Foot Waffle (p = .069). The Generalized Estimating Equations (GEE) method revealed the Foot Waffle was four times more likely not to suspend the heel off the bed than the pillow, and the left heel was four-and-a-half times more likely to have higher interface pressures than the right. There was no significant difference between groups in incidence of lower-extremity pressure ulcers, but patients using the Foot Waffle developed pressure ulcers significantly sooner (10 days versus 13 days for the pillow). Heels require additional protection beyond the use of specially beds and mattress overlays. In order to provide continuous heel suspension, clinicians must consider proper fit, turning schedules, patient position, patient activity, and presence of additional equipment when selecting heel protection products. This study illustrates how difficult it is to control for all these factors when doing clinical research. Note: This study was done with a Foot Waffle model that has since been redesigned. No research is available on the new model.