Assessment of delirium using the PRE-DELIRIC model in an intensive care unit in Argentina

OBJECTIVE: To describe the incidence of and risk factors for delirium in the intensive care unit of a tertiary care teaching hospital in Argentina and to conduct the first non-European study exploring the performance of the PREdiction of DELIRium in ICu patients (PRE-DELIRIC) model. METHODS: Prospective observational study in a 20-bed intensive care unit of a tertiary care teaching hospital in Buenos Aires, Argentina. The PRE-DELIRIC model was applied to 178 consecutive patients within 24 hours of admission to the intensive care unit; delirium was assessed with the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). RESULTS: The mean age was 64.3 ± 17.9 years. The median time of stay in the intensive care unit was 6 (range, 2 - 56) days. Of the total number of patients, 49/178 (27.5%) developed delirium, defined as a positive CAM-ICU assessment, during their stay in the intensive care unit. Patients in the delirium group were significantly older and had a significantly higher Acute Physiological and Chronic Health Evaluation II (APACHE II) score. The mortality rate in the intensive care unit was 14.6%; no significant difference was observed between the two groups. Predictive factors for the development of delirium were increased age, prolonged intensive care unit stay, and opioid use. The area under the curve for the PRE-DELIRIC model was 0.83 (95%CI; 0.77 - 0.90). CONCLUSIONS: The observed incidence of delirium highlights the importance of this problem in the intensive care unit setting. In this first study conducted outside Europe, PRE-DELIRIC accurately predicted the development of delirium.