The Relevance of Support Surfaces in Pressure Ulcer Prevention and Treatment

As a co-chair of the AAWC guideline committee pressure ulcer project I was anxious to find what our search for clinically significant research on support surfaces would reveal. I was disappointed to find an extensive search and collaboration with other international wound associations failed to provide definitive direction regarding concrete methods for determining product efficacy. Only gross categories exist relative to foam, gel, air & air fluidized pressure redistribution devices. All devices are lumped into one of these categories yet individual foam, gel & air devices vary widely in regard to structure, efficacy, comfort and features. There are no standards that can assign a device to a level of performance such as number of air cylinders, depth of air cylinders, flotation control features, noise & heat generation factors, power failure capabilities, safety features against fall/entrapment risk, type of surface material, or instruction for use. No independent evaluation center exists that rates the level of device performance. Air flotation mattress category is inclusive of the most basic model up to the most sophisticated. Even assigned subcategories such as low air loss do not ensure equal performance capabilities.

The relevance of pressure mapping is largely disputed yet continues as the primary tactic for defining support device efficacy. These measures are obtained on healthy subjects who exhibit no postural deformities, immobility or positioning challenges. They are generally done in a supine position without head elevation unlike any real product users. They provide information on surface pressure only and reveal nothing about tissue compression, perfusion or distortion. Only a small number of devices have provided a more scientific approach in looking at product performance using CT scan, PET scan & TCPO2 values. Without science base the clinician is left to evaluate product efficacy through rigorous clinical evaluation & outcome observation on multiple subjects over time.

In my 30 years of wound consulting I have observed that support surfaces on bed and, even more so, on seating systems is a low priority in many treatment programs. I have evaluated countless numbers of patients for wound digression and in the majority of cases find they have one or more of the following; inadequate pressure redistribution equipment on bed and/or chair, improper settings on existing equipment, improper use of equipment, lack of adjunctive extremity off-loading devices and/or ill-fitting seating systems. Upgrading mattresses to a more efficient model that overcomes hammocking or bottoming out can often improve wound healing without any change in local care. Sometimes it is as simple as individually adjusting the control settings on the mattress to improve pressure redistribution instead of using the generic manufacturer's reference. Other times a high end mattress may be in use when the patient spends 10+ hours sitting in an ill-fitting wheelchair with a substandard cushion and seating revision alone has elicited ulcer healing. I have discovered that environmental assessment is critical to ulcer healing and improvements in pressure redistribution can provide healing outcomes despite nutritional issues and co-morbidities when adequate wound bed preparation and local care is in place.

I have gained faith in select devices largely through trial & error and likewise have ceased to use certain devices due to repeated failures to heal despite a comprehensive treatment program. I've observed that devices can make a difference in your healing outcomes and no single device is suitable to any population. I'm always prepared to trial several different devices on those that exhibit more complex posturing or are uniquely weighted individuals to determine the most effective product, thus find product rental useful before purchase. I encourage and support development of scientific gold standards for defining product efficacy. Our product committee strives to select off-loading products that achieve the best patient outcomes.

Sue Girolami, Clinical Manager, Therapy Support, Inc.