Neuroprotective Core Measure 4: Safeguarding Sleep — Its Value in Neuroprotection of the Newborn

Reducing Noise in the NICU

BACKGROUND

In the neonatal intensive care unit (NICU), elevated noise negatively impacts the neurodevelopmental environment, interrupts sleep, and can affect brain development in neonates. The American Academy of Pediatrics recommends that noise levels in the NICU should not exceed 45 dB.

PURPOSE

The project aims were to: (1) decrease average noise level by 10% from baseline and (2) decrease exposure to severe noise (>65 dB) to <5% of the time.

METHODS

This quality improvement project was conducted during 2021-2022 as a pre/post observational design in a Level IV NICU in New York City. We monitored sound levels for 20-24 h, 5 d/wk. Quality improvement interventions included: novel approaches to staff education, visual cues for when noise thresholds were exceeded, parent education, including access to personal decibel meters, technical improvements to vital sign monitors and entry doors, and defined quiet times (HUSH) for 2 h each 12-hour shift.

RESULTS

Education efforts and technical improvements successfully reduced median noise levels within the stepdown unit ( P < .001), though not in the acute care NICU. In contrast, the implementation of 2-hour periods of enforced "quiet time" every 12 h effectively reduced both median noise levels and the incidence of severe noise (>65 dB) in both locations.

IMPLICATIONS FOR PRACTICE AND RESEARCH

The HUSH strategy may be a sustainable way to decrease noise in the NICU. Future projects should prioritize education and dedicated quiet times to align with recommended standards, while research should explore the long-term developmental impacts of excessive noise levels on neonatal growth.

Sleep state organisation of moderate to late preterm infants in the neonatal unit

BACKGROUND

Sleep supports neurodevelopment and sleep architecture reflects brain maturation. This prospective observational study describes the nocturnal sleep architecture of healthy moderate to late preterm (MLP) infants in the neonatal unit at 36 weeks post menstrual age (PMA).

METHODS

MLP infants, in the neonatal unit of a tertiary hospital in Ireland from 2017 to 2018, had overnight continuous electroencephalography (cEEG) with video for a minimum 12 h at 36 weeks PMA. The total sleep time (TST) including periods of active sleep (AS), quiet sleep (QS), indeterminate sleep (IS), wakefulness and feeding were identified, annotated and quantified.

RESULTS

A total of 98 infants had cEEG with video monitoring suitable for analysis. The median (IQR) of TST in the 12 h period was 7.09 h (IQR 6.61-7.76 h), 4.58 h (3.69-5.09 h) in AS, 2.02 h (1.76-2.36 h) in QS and 0.65 h (0.48-0.89 h) in IS. The total duration of AS was significantly lower in infants born at lower GA (p = 0.007) whilst the duration of individual QS periods was significantly higher (p = 0.001).

CONCLUSION

Overnight cEEG with video at 36 weeks PMA showed that sleep state architecture is dependent on birth GA. Infants with a lower birth GA have less AS and more QS that may have implications for later neurodevelopment.

IMPACT

EEG provides objective information about the sleep organisation of the moderate to late preterm (MLP) infant. Quantitative changes in sleep states occur with each week of advancing gestational age (GA). Active sleep (AS) is the dominant sleep state that was significantly lower in infants born at lower GA. MLP infants who were exclusively fed orally had a shorter total sleep time and less AS compared to infants who were fed via nasogastric tube.