Lead. Sleep is essential for recovery, yet critically ill children in the pediatric intensive care unit (PICU) may experience profound sleep disruption that goes unrecognized. A new observational study published in Acta Paediatrica provides the first comprehensive, age-adjusted comparison of sleep architecture in critically ill children versus non-critically ill controls, using full polysomnography. The findings reveal that nearly all critically ill children had severely disrupted sleep and more than three-quarters showed abnormal electroencephalogram (EEG) patterns, raising urgent questions about the impact of PICU care on neurologic recovery in young patients.
What they found. The study enrolled 25 critically ill children admitted to the PICU at Erasmus MC Sophia Children’s Hospital in Rotterdam (median age 3.6 months) and compared them with 120 non-critically ill children referred for suspected sleep-disordered breathing (median age 36.7 months). All participants underwent overnight polysomnography, and the PICU cohort’s sleep metrics were evaluated against age-specific reference ranges.
The results were striking. In critically ill children, nighttime total sleep accounted for only 50.9 percent (interquartile range 49.5 to 55.5) of total 24-hour sleep, meaning nearly half of all sleep occurred during daytime hours. Rapid eye movement (REM) sleep was reduced in 96.0 percent of critically ill children, and deep non-rapid eye movement (NREM) sleep was reduced in 66.7 percent. Overall, EEG abnormalities were identified in 76.0 percent of PICU patients, indicating that sleep disruption was accompanied by measurable changes in brain electrical activity.
The non-critically ill comparison group also showed sleep disturbances, though of a different character. Reduced REM sleep was common in early infancy, while older children in this group tended to have shorter, more fragmented sleep patterns. These findings suggest that while some degree of sleep disruption may be expected during childhood illness, the magnitude and severity seen in PICU patients is far beyond what typical illness produces.
The authors defined REM sleep reduction as a REM proportion below the fifth percentile of age-specific reference values, and deep NREM sleep reduction as a proportion of NREM stage 3 (slow-wave sleep) below the same threshold.
Why it matters. The PICU environment is notoriously hostile to normal sleep. Continuous monitoring equipment, alarm sounds, frequent nursing interventions, mechanical ventilation, and 24-hour lighting are all known disruptors. However, this study goes further by demonstrating that the disruption is not merely subjective or behavioral. It is objectively measurable in sleep architecture and brain electrical activity, and it affects nearly every critically ill child.
This matters because sleep is not a passive state. REM sleep supports memory consolidation and emotional regulation, while deep NREM sleep is critical for restorative processes, immune function, and metabolic recovery. A critically ill child who is deprived of these sleep stages may face delayed recovery, prolonged ventilation, worse neurodevelopmental outcomes, and increased risk of delirium. The fact that 76 percent of these children had abnormal EEGs raises the possibility that unrecognized neurologic dysfunction or sedative effects are compounding the sleep disruption.
The study also highlights that age-adjusted reference ranges are essential when evaluating pediatric sleep. A sleep pattern that is normal for a 3-month-old may be severely abnormal for a 3-year-old, and failing to account for this can lead to underrecognition of clinically significant disturbances.
Limits. The study has important limitations. The sample size of critically ill children was relatively small (n=25), which limits statistical power and the ability to adjust for potential confounders such as diagnosis, severity of illness, medications, and ventilation status. The critically ill and non-critically ill groups differed substantially in median age (3.6 months vs. 36.7 months), and although the authors used age-specific reference ranges, direct comparison between the two groups is challenging. The non-critically ill group consisted of children referred for suspected sleep-disordered breathing, meaning they were not healthy controls and may themselves have had baseline sleep abnormalities. Additionally, polysomnography in the PICU setting may not fully capture the child’s typical sleep pattern, as the measurement environment itself influences sleep. The study design was cross-sectional, so it cannot establish causality between PICU admission and the observed sleep changes, nor can it determine whether these disturbances persist after discharge.
Bottom line. Critically ill children on the PICU experience severe, objectively measurable disruptions in sleep architecture, including near-universal reduction in REM sleep and a high prevalence of EEG abnormalities. These findings underscore the need for systematic sleep monitoring and sleep-protective protocols in pediatric intensive care, as well as further research into whether interventions such as environmental modifications, sedation stewardship, and circadian rhythm preservation can improve sleep quality and, ultimately, clinical outcomes.