Objective: The purpose of this study was to evaluate the noise of three newborn infant isolettes.
Study design: An observational, prospective study evaluated noise in three isolettes (Ohmeda, Air Shields, and Drager). The study measured interior isolette noise production during quiet noise situations and isolette noise attenuation of added low- and high-frequency noise. Noise was measured on the decibel A scale and in the 125 Hz and 1000 Hz bands.
Results: During quiet conditions the Ohmeda and Drager isolettes had the least noise production on the basis of decibel A levels (p < 0.001). Low-frequency noise on the decibel A scale was attenuated the most by the Drager isolette (p < 0.001), although the overall difference may be clinically insignificant. The Ohmeda isolette attenuated high-frequency noise by 28.4 dB as measured on the decibel A scale, which was greater than values for the Drager (22.8 dB) and Air Shields (14 dB) isolettes (p < 0.001).
Conclusions: High-frequency noise attenuation by the Ohmeda and Drager isolettes is clinically and statistically greater than high-frequency noise attenuation by the Air Shields isolette.