Ask the treatment expert ... about pressure maps
Rosalyn Jordan, RN, BSN, MSc, CWOCN, WCC
Can you explain the purpose of a pressure map and the usefulness when evaluating the function of a therapeutic support surface?
Although pressure mapping systems have been frequently used to measure the pressure or tissue load supported by the therapeutic support surfaces, the performance of support surfaces with pressure mapping can be very inconsistent, costly and misleading when used to determine the most effective therapy for the individual patient.
A pressure map is created by a thin pad embedded with flexible sensors that transmit the location and pressure reading to a computer. A color-coded map of the body is generated by the computer. The computerized color output on the computer indicates the magnitude of pressure in that snapshot in time based on the ranges set within the computer programming.
A number of factors can influence the sensors and mapping systems.
Pressure mapping at bedside does not follow adherence to the rigorous testing methods utilized by independent laboratories. Pressure maps should be conditioned to the ambient room temperature and calibrated prior to testing.
Also, pressure maps have inherent issues such as hysteresis and creep.
Hysteresis occurs when loading the pressure map such as sliding the individual on the mapping system.
Creep occurs over time as the pressure on the sensors increases the longer the pressure is applied.
Bedside pressure mapping may be useful as an individual therapeutic intervention when utilized as a visual clue for positioning information or reminders to prevent and treat pressure ulcers. But support surface performance and selection based on standardized testing in a controlled laboratory environment is more effective.