Ambient noise and neonatal hemodynamics - An observational cross-sectional study

Background: Previous studies reported numerous adverse effects of noise in the newborns such as increase in the heart rate (HR) and respiratory frequency and drop in the oxygen saturation. Objective: The objective of this study was to study the effect of ambient noise levels in neonatal intensive care unit (NICU) on the hemodynamics of neonates. Materials and Methods: This was a hospital-based cross-sectional observational study which aimed at assessing the ambient noise levels in the NICU with a digital decibel meter and its effect on HR, respiratory rate (RR), and oxygen saturation. A total of 105 neonates (both preterm and term) having stable cardiorespiratory status were enrolled in the study. Results: The mean noise level recorded in the NICU was 56.2 dB. The lowest noise level was recorded at 8 am, that is, 46 dB while the highest recorded level was at 2 pm, that is, 65 dB in different areas of the NICU. There was a statistically significant increase in the HR in relation to the noise levels at all times (p<0.0001). The RR also showed a significant rise in relation to the increase in noise level (p<0.0001 at 2 pm with maximum noise level). The oxygen saturation showed a negative correlation and a statistically significant drop at 2 pm when maximum noise level was recorded (p<0.0001). Changing shifts and more number of healthcare personnel were important factors contributing to increased noise levels at 2 pm. Conclusion: Noise levels of >56 dB affected the hemodynamics of the newborn. The maximum increase in the mean HR, RR, and drop in saturation was observed at 2 pm. Staff sensitization and attitude change are needed to decrease the noise pollution in NICU