Characterizing Sleep Disruption and Delirium in Children After Cardiac Surgery: A Feasibility Study

OBJECTIVES: Patients in the pediatric cardiac ICU are frequently exposed to pharmacologic and environmental factors that predispose them to sleep disturbances and may increase the risk of delirium. In this pilot study, we sought to demonstrate the feasibility of actigraphy monitoring in pediatric cardiac ICU patients to investigate the association between sleep characteristics and delirium development. DESIGN: Prospective observational pilot study. SETTING: Pediatric cardiac ICU in an academic children's hospital in the United States. PATIENTS: Children admitted to the pediatric cardiac ICU after cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Nineteen enrolled patients wore actigraphy watches that provided data for a total of 63 pediatric cardiac ICU days. The median pediatric cardiac ICU length of stay was 2 days (interquartile range, 1-3 d). The median sleep episode among all patients was 37 minutes in duration (interquartile range, 18-46 min), and the longest sleep episode was a median of 117 minutes (interquartile range, 69-144 min). Sixty-one percent of patients (95% CI, 36-83%) screened positive for delirium at least once during admission, and the median number of delirious days among those who were positive was 2 days (interquartile range, 1-3 d). The median percent sleep time was 43% for delirious patients and 49% for those with no delirium, with similar median sleep and longest sleep episodes. The median ratio of daytime activity/24-hr activity was 54% (interquartile range, 49-59%) in both groups. CONCLUSIONS: Actigraphy monitoring in conjunction with delirium screening is feasible in infants and children admitted to the pediatric cardiac ICU after cardiac surgery. Our data suggest that most children in the pediatric cardiac ICU experience severe sleep disruption and delirium is common. These pilot data provide important insights for the design of a large-scale observational study to investigate potential causal relationships between sleep disruption and delirium in the pediatric cardiac ICU.