Interface pressure characteristics of alternating air cell mattresses in persons with spinal cord injury

To examine interface pressure characteristics for two alternating air cell mattresses used for pressure ulcer prevention and treatment in a spinal cord injury population.

Prospective evaluation of Dynamic Flotation System (DFS) mattress and the Pegasus Airwave Mattress. Subjects acted as their own controls.

Veterans Affairs Medical Center Spinal Cord Injury Unit.

Convenience sample of 15 subjects with spinal cord injuries.

Minimum, maximum, and average interface pressures, and interface pressure range were measured by use of a force-sensing array system. The sacrum was chosen as the area of interest. Recordings lasted 9.5-10 minutes. Analyses were performed on 19 subjects in the supine and 45-degree upright positions for both mattresses.

Maximum and average interface pressures and interface pressure ranges were significantly higher, whereas minimum interface pressures were significantly lower on the Pegasus vs the DFS. For either mattress, the 45-degree position resulted in significantly greater interface pressures. There was no consistent correlation found between interface pressures and body mass index.

Interface pressure characteristics of these two mattresses are very different, and neither mattress retains performance in the 45-degree position. Which interface pressure characteristic is most clinically relevant remains undetermined. Avoidance of the 45-degree sitting position is recommended.