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.