Pressure ulcers in palliative ward patients: hyponatremia and low blood pressure as indicators of risk

BACKGROUND: Prevention strategies for pressure ulcer formation remain critical in patients with an advanced illness. We analyzed factors associated with the development of pressure ulcers in patients hospitalized in a palliative care ward setting. PATIENTS AND METHODS: This study was a retrospective analysis of 329 consecutive patients with a mean age (± standard deviation) of 70.4±11.8 years (range: 30–96 years, median 70.0 years; 55.3% women), who were admitted to the Palliative Care Department between July 2012 and May 2014. RESULTS: Patients were hospitalized for mean of 24.8±31.4 days (1–310 days, median 14 days). A total of 256 patients (77.8%) died in the ward and 73 patients (22.2%) were discharged. Two hundred and six patients (62.6%) did not develop pressure ulcers during their stay in the ward, 84 patients (25.5%) were admitted with pressure ulcers, and 39 patients (11.9%) developed pressure ulcers in the ward. Four factors assessed at admission appear to predict the development of pressure ulcers in the multivariate logistic regression model: Waterlow score (odds ratio [OR] =1.140, 95% confidence interval [CI] =1.057–1.229, P=0.001), transfer from other hospital wards (OR =2.938, 95% CI =1.339–6.448, P=0.007), hemoglobin level (OR =0.814, 95% CI =0.693–0.956, P=0.012), and systolic blood pressure (OR =0.976, 95% CI =0.955–0.997, P=0.023). Five other factors assessed during hospitalization appear to be associated with pressure ulcer development: mean evening body temperature (OR =3.830, 95% CI =1.729–8.486, P=0.001), mean Waterlow score (OR =1.194, 95% CI =1.092–1.306, P<0.001), the lowest recorded sodium concentration (OR =0.880, 95% CI =0.814–0.951, P=0.001), mean systolic blood pressure (OR =0.956, 95% CI =0.929–0.984, P=0.003), and the lowest recorded hemoglobin level (OR =0.803, 95% CI =0.672–0.960, P=0.016). CONCLUSION: Hyponatremia and low blood pressure may contribute to the formation of pressure ulcers in patients with an advanced illness.