Use of a Support Surface Standard to Test the Effects of a Turning and Positioning Device Versus Low-Air-Loss Therapy on Temperature and Humidity.

Background: Turning and repositioning devices (TRDs) help to reduce strain on caregivers, but clinicians question their effects on humidity and temperature (microclimate) at the skin surface that may increase risk of pressure ulcers.

Objective: To pilot the use of a standard test for support surfaces to compare microclimate at the skin surface in three scenarios: (1) on a low-air-loss (LAL) surface, (2) on a representative TRD with a basic underpad (TRDU) placed on a LAL surface, and (3) on a negative control with full occlusion. The results are designed to inform clinical decision-making in using a TRD on a LAL surface and the viability of using this test to study TRDs.

Design: Measuring humidity and temperature at the device-surface interface using a heated moisture-exuding bronze thermodynamic human model in a laboratory setting.

Main Outcome Measure: Humidity and temperature levels across 3 hours 15 minutes of continuous loading with a 45-second complete unloading to simulate a position change at 3 hours.

Main Results: Relative humidity on the TRDU was below that on the LAL surface for the first 110 minutes and was markedly lower than the negative control for the remainder of humidity testing. Temperature on the TRDU was well below the negative control and negligibly higher than the surface alone throughout testing. The position change enhanced the effects of the TRDU.

Conclusions: The support surface standard test appears useful in evaluating TRDs. This TRD along with the basic underpad is more comparable to a LAL surface than to full occlusion in managing the microclimate of the skin and pressure ulcer risk.