Comparison of noise levels caused by four different neonatal high-frequency ventilators.

Abstract

To test the hypothesis that neonatal high-frequency ventilators create different noise levels depending upon ventilator settings and device-specific properties. Three neonatal ventilators with built-in high-frequency options (Babylog 8000, Infant Star, Stephanie) and an exclusive high-frequency oscillator (SensorMedics 3100A). Noise levels were recorded by a microphone and measured by a decibel recording device at a defined distance from a test lung. Noise levels were highest for the SensorMedics and the Babylog (70 dB and 62 dB, respectively). Whereas the SensorMedics increased noise production with amplitude, the Babylog remained at a constant level. The Infant Star (52 dB) and the Stephanie (54 dB) were significantly less noisy at their maximum levels of amplitude (40 mbar and 50 mbar, respectively). Most levels recorded were below those measured within an incubator without the use of a ventilator. We conclude that neonatal high-frequency ventilators do not represent a major contribution to noise levels for newborns in neonatal intensive care units (NICUs).