In the 1980s, most NICUs were just beginning to recognize the effect of noise on the preterm infant. A number of studies documented high and potentially harmful ambient and peak sound levels in neonatal units.1,2 These data were the basis for many of the sound-reduction strategies, both behavioral and structural, employed in NICUs during subsequent years.

However, during the same interval significant changes in nursing practice, such as greater use of technology, increased patient acuity, and more emphasis on developmental care, have taken place in the NICU. To find out if improvements in care have had any influence on the sound environment of the NICU, Thomas and Uran3 replicated a study originally published in 1989 in which they evaluated ambient noise levels in a Level III NICU.

In the same NICU as the 1989 study, these nurse researchers measured sound levels in the identical unit locations and within an empty newer-model incubator. They found that contrasted with 16 years earlier, overall room sound levels were lower but still did not consistently fall within the recommended ranges for the newborn in intensive care.4 Sound levels associated with caregiving, equipment, and other activities in 2005 were similar to those recorded in 1989. Sources of significantly higher noise were the same at both time periods, and included closing porthole doors, incubator alarms, dropping the head of the incubator platform, and using the incubator as a work surface.

Two decades of awareness have not completely solved the problem of excessive noise in the NICU. These findings point to additional actions that nurses can take to foster noise abatement in the NICU.

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