Delirium assessment in postoperative patients: Validation of the Portuguese version of the Nursing Delirium Screening Scale in critical care

Abstract

Background and objectives: The aim of this study was to validate the Portuguese version of the Nursing Delirium Screening Scale (Nu-DESC) for use in critical care settings. Methods: We simultaneously and independently evaluated all postoperative patients admitted to a surgical Intensive Care Unit (SICU) over a 1-month period for delirium, using the Portuguese versions of both the Nu-DESC and the Intensive Care Delirium Screening Checklist (ICDSC) within 24 hours of admission by both the research staff physician and one bedside nurse. We determined the diagnostic accuracy of the Nu-DESC using sensitivity, specificity and ROC curve analyses. We assessed reliability between nurses and the research staff physician for Nu-DESC by intraclass correlation coefficient (ICC). We assessed agreement and reliability between Nu-DESC and ICDSC by overall and specific proportions of agreement and by kappa statistics. Results: Based on the ICDSC, we diagnosed delirium in 12 of the 78 patients. Reliability between nurses and the staff physician for total Nu-DESC score was high. Agreement between nurses and staff physician in the delirium diagnosis was perfect. The proportion of overall agreement between Nu-DESC and ICDSC in the delirium diagnosis was 0.88 and the kappa ranged from 0.79 to 0.93. Nu-DESC Sensitivity was 100 and specificity was 86%. Conclusions: The Portuguese version of the Nu-DESC appears to be an accurate and reliable assessment and monitoring instrument for delirium in critical care settings. Keywords: Delirium, Postoperative care, Critical care