To determine the incidence, duration, and clinical correlates of delirium in critically ill children, and examine its association with sedation depth using the Richmond Agitation–Sedation Scale (RASS).

Delirium is a frequent but underrecognized disturbance of attention, awareness, and cognition in critically ill children. It is associated with prolonged mechanical ventilation, extended ICU stays, and adverse neurocognitive outcomes. Routine bedside screening with validated pediatric tools may enhance early detection, guide safer sedation strategies, and mitigate long-term sequelae.

A prospective observational study was conducted at the Pediatric Intensive Care Unit (PICU) of Hospital Francisco Icaza Bustamante (Ecuador). Twenty patients aged 1 month–14 years (mean 6.3 ± 3.8 years; 60% male) were enrolled. Daily paired assessments of sedation (RASS; pediatric-adapted scoring when indicated) and delirium (CAPD for younger or developmentally variable children; pCAM-ICU for older patients) were performed throughout admission. Demographic, clinical, and pharmacologic data were collected. Associations between sedation depth, delirium duration, and outcomes were analyzed using Spearman’s ρ and Mann–Whitney U tests.

Delirium occurred in 35% (n = 7) of patients, lasting 2.4 ± 1.1 days. Moderate-to-deep sedation (RASS ≤ –3) preceded delirium in 71% of affected patients versus 25% without delirium (p = 0.02). Delirium cases had longer PICU stays (8.9 ± 4.2 vs. 5.1 ± 2.8 days; p = 0.03). Prolonged sedative exposure correlated with delirium duration (p = 0.04). Younger age (< 5 years) trended toward association but was not significant (p = 0.44).

Delirium affected over one-third of PICU patients and was linked to deeper sedation, longer sedative exposure, and extended ICU stays. Routine RASS-based and age-appropriate delirium monitoring may aid early detection and support cognition-sparing sedation practices. Larger studies are warranted to confirm these associations and clarify causality.