Factors associated with delirium in critical patients in a health institution in Bucaramanga, Colombia

Abstract

Objective: To determine the incidence and the factors associated with delirium in intensive care unit patients.

Methods: A cohort study conducted on 134 patients in the intensive care unit at a clinic in Bucaramanga, Colombia., who were recruited in the first 24hours following admission and on whom the Richmond Agitation-Sedation Scale (RASS), PRE-DELIRIC version in Spanish, and Confusion Assessment method for Intensive Care Unit (CAM-ICU) were applied; the outcome was evaluated through daily monitoring with CAM-ICU.

Results: The incidence of delirium was 20.2%, the predominating type was hypoactive at 66.7%, followed by the hyperactive type at 7.4% and mixed at 25.9%. Fifty-two percent of the patients with delirium died. In the bivariate analysis, the use of sedatives (Relative Risk(RR) 2.4, 95% confidence interval (95% CI) = 1.2-4.5), infection (RR = 2. 8, 95% CI=1.3-5.9), metabolic acidosis (RR = 4 3, 95% CI=2.3-8.0), mechanical ventilation (RR = 4 6, 95% CI=2.0-10.6), aged over 60 years (RR = 2 3, 95% CI=1.09-5.3) and APACHE score greater than 14 (RR = 3. 0) (95% CI=1.1-8.2) were identified as risk factors for delirium. The multivariate analysis only found a relationship with infection (RR = 3 8, 95% CI=1.6-9.1) and being aged over 60 years (RR = 3 2, 95% CI 1.2-8.3).

Conclusions: delirium is frequent in patients in the intensive care unit, especially the hypoactive type. Half of the patients with delirium died. The main risk factors for delirium are infection and being over 60 years age, therefore, delirium prevention activities should focus on these critical patients.

Keywords: Delirium; Delírium; Incidence; Incidencia; Intensive Care Unit; Unidad de Cuidados Intensivos.