A Retrospective Analysis to Evaluate Seasonal Pressure Injury Incidence Differences Among Hip Fracture Patients in a Tertiary Hospital in East China

Abstract

Patients with a hip fracture are at high risk for pressure injury. A retrospective review of the electronic medical records of consecutive patients with a hip fracture treated in 2016 in a single tertiary hospital in east China were examined to investigate whether time of year affected the incidence of hospital-acquired pressure injury. Data collected included demographic characteristics (patient name, hospital number, age, gender, and body mass index); possible risk factors for pressure injury, such as presence of diabetes mellitus, admission hemoglobin, admission albumin, length of surgery, and the lowest and/or last Braden Scale score before pressure injury developed; and pressure injury information, which included time of occurrence (days after surgery), location (sacrum and coccyx, ischial tuberosity, or heel), stage, and treatment outcome. Pressure injury incidence was calculated with 95% confidence intervals (CIs) in each month and season (spring, summer, autumn, and winter). Odds ratios (ORs) and 95% CIs were calculated as estimates of risk. Multivariate logistic regression was used for risk factors. Of the 235 patients with a hip fracture included in the study, 95 (40.4%) were male, 140 (59.6%) were female, and mean age was 70.4 ± 10.5 (range 48-81) years. Thirty-one (31) patients (13.2%, 95% CI 9.1%-18.2%) developed 37 pressure injuries, 30 of which (81.1%) were Stage 1. The incidence of pressure injury was lowest in November (5.0%; 95% CI: 0.0%-24.9%) and highest in June (22.7%; 95% CI: 7.8%-45.4%). Average Braden Scale scores (14.2 ± 3.2) were lower in June than in November (16.6 ± 3.5), owing to differences in the Braden Scale skin moisture subscale. Seasonally, the incidence of pressure ulcers was 20.8% (95% CI: 12.2%-32.0%) in the summer compared to 7.5% (2.5%-16.6%) in autumn (crude OR 3.3; 95% CI:1.0-12.1; P = .025). Multivariate logistic regression analysis showed the Braden Scale score was the only independent risk factor (P <.05) for pressure injury incidence. Adjusting for the Braden score, the OR of summer season was 1.537 (95% CI: 0.964-2.872). The findings suggest that humidity and temperature levels, which are very high in the summer in China, may affect pressure injury incidence and that the Braden Scale score - especially the skin-moisture level subscore - is a valid predictor of pressure injury risk in this population. While more research is needed, additional pressure injury prevention strategies should be provided for patients hospitalized with a hip fracture in the summer months.