They noted that excessive noise was widely known to have negative effects on health and highlighted that children in neonatal intensive care units were among the most vulnerable.
“Even recent studies show that ambient NICU noise often exceeds recommended levels”
To help preterm infants make a smooth transition to life outside of the womb, some NICUs have instituted set quiet times to limit children’s exposure to potentially dangerous levels of noise.
Researchers conducted what they describe as one of the first studies linking the “quiet time soundscape” inside NICUs with infant health.
The study authors examined the effects of quiet time implementation in multiple NICUs on infants up to 18 months after implementation.
This gave them a sense of which features of quiet time policies had the largest impact on the youngest patients in the hospital, said the researchers.
They worked with nursing staff as they developed their own quiet time guidelines, including limiting conversations, dimming lights, and coordinating scheduled cleaning services, at set hours every afternoon and night.
The researchers then analysed how each NICU’s soundscape changed throughout the day.
Acoustic measurements revealed that certain stressful pitches were quieter, very loud sounds occurred more infrequently, and total amount of quiet time throughout the day was longer.
The infants in the NICU had healthier heart rates during quiet time hours, said the study authors.
From this data, the group recommended using quiet time protocols to help NICU patients in addition to implementing architectural noise reduction strategies in NICUs.
“There are large and pressing gaps in the literature that need immediate attention”
The researchers said the hoped their work generated interest in how noise affected other types of hospital patients and beyond, including how public spaces were designed.
The study was carried out by researchers from the University of Nebraska-Lincoln, George Washington University and Baptist Health South Florida.
Study author Dr Erica Ryherd said: “Although the NICU noise literature dates back more than 40 years, even recent studies show that ambient NICU noise often exceeds recommended levels.
“Despite the growing evidence of the negative impacts of NICU soundscapes on infants, there are large and pressing gaps in the literature that need immediate attention before ideal, evidence-based NICU soundscapes are achievable and more widely implemented,” she added.
The findings from the story are due to be reported this week at a meeting of the Acoustical Society of America in Louisville, Kentucky.