Noise measurement in NICUs and incubators with newborns: a systematic literature review

Abstract

This systematic literature review evaluated the methodological quality of studies measuring noise in neonatal intensive care units. A manual and also electronic search in the Medline, Scielo, Lilacs, BDENF, WHOLIS, BDTD, Science Direct, NCBI and Scirus databases resulted in 40 studies that met the criterion "measuring noise in neonatal units and/or incubators". Experts in neonatology and acoustics validated the critical analysis instrument, which obtained a mean = 7.9 (SD=1.3). The inter-observer reliability in 18 articles resulted in an Intra-class correlation coefficient (ICC) of 0.89 (CI 0.75-0.95). The quality indicators were 50% better in those studies that measured noise only in the unit's environment and associated measuring strategies to the physical area. The results showed great methodological variability, which hindered comparability and raised the probability of bias. The conditions required to ensure internal and external validity were observed in few studies.

Are high flow nasal cannulae noisier than bubble CPAP for preterm infants?

“…Readings were taken from the same ear, each for a period of 10 s, to produce an equivalent continuous sound level, a measure that accounts for fluctuations in sound energy over a given timeframe, as recommended previously 18. Three such readings were taken, and the results averaged to produce a final measurement at each level of support.…”

Assessment of Noise Exposure to Children: Considerations for the National Children’s Study

“…In a study of the acoustic environment in several mid-Atlantic region NICUs, the hourly mean sound levels ranged from 53.9 dBA to 60.6 dBA, well above the American Academy of Pediatrics (AAP) recommended 45 dBA mean level [28]. Nogueira et al [29] pointed out issues with noise measurement in NICUs, including placement of the microphone in the incubator, continuous low frequency noise such as the incubator's motor, and intermittent middle frequency (human voice) and high frequency (alarms of equipment, telephones) noise. Situations such as opening and closing the hatches or the intensive care doors, moving the mattress tray, or putting objects on the dome may produce noise that varies from 78 to 93 dBA, exceeding the AAP-recommended impulse noise maximum of 65 dBA.…”

“…Situations such as opening and closing the hatches or the intensive care doors, moving the mattress tray, or putting objects on the dome may produce noise that varies from 78 to 93 dBA, exceeding the AAP-recommended impulse noise maximum of 65 dBA. Such noise can affect newborns, increasing their heart rate and respiratory frequency, dropping their oxygen saturation, diminishing the duration of their sleep state and hindering their ability to stay in a deep sleep state, and also causing alterations in their motor activity [29,30]. …”

Effect of peer education on the noise management in Iranian neonatal intensive care unit

“…Despite the advances, the premature infants are still at the risk of developmental problems that may remain with them throughout their life. [ 1 ] Receiving the sensory stimuli directly affects the brain development of fetuses and infants. Most of the human sensory systems develop before birth, and receiving high or low stimuli may interfere with the normal brain development.…”