Pressure mapping to prevent pressure ulcers in a hospital setting: A pragmatic randomised controlled trial

Background: Pressure ulcers cause suffering to patients and costs to society. Reducing pressure at the interface between the patient's body and the support surface is a valid clinical intervention for reducing the risk of pressure ulcers. However, studies have shown that knowledge of how to reduce pressure and shear and to prevent pressure ulcers is lacking. Objective: To evaluate the effect of a pressure mapping system on pressure ulcer prevalence and incidence in a hospital setting. Design: Pragmatic randomised controlled trial. Setting: A geriatric/internal medical ward with 26 beds in a Swedish university hospital. Participants: 190 patients were recruited (intervention: n = 91; control: n = 99) over a period of 9 months. Patients were eligible if they were over 50 years old, admitted to the ward between Sunday 4 pm and Friday 4 pm, and expected to stay in the ward >= 3 days. Intervention: The continuous bedside pressure mapping system displays the patient's pressure points in real-time colour imagery showing how pressure is distributed at the body mat interface. The system gives immediate feedback to staff about the patient's pressure points, facilitating preventive interventions related to repositioning. It was used from admittance to discharge from the ward (or 14 days at most). Both intervention and control groups received standard pressure ulcer prevention care. Results: No significant difference in the prevalence and incidence of pressure ulcers was shown between intervention and control groups. The prevalence of pressure ulcers in the intervention group was 24.2% on day 1 and 28.2% on day 14. In the control group the corresponding numbers were 18.2% and 23.8%. Seven of 69 patients (10.1%) in the intervention group and seven of 81 patients (8.6%) in the control group who had no pressure ulcers on admission developed category 1 and category 2 ulcers during their hospital stay. The incidence rate ratio between the intervention and control groups was 1.13 (95% CI: 0.34-3.79). Conclusions: This study failed to demonstrate a beneficial effect of a pressure mapping system on pressure ulcer prevalence and incidence. However, the study could have increased staff awareness and focus on pressure ulcer prevention, thus affecting the prevalence and incidence of pressure ulcers in a positive way in both study groups. It is important to further investigate the experience of the multidisciplinary team and the patients regarding their use of the pressure mapping system, as well as strengths and weaknesses of the system.