Efficacy of a low cost protocol in reducing noise levels in the neonatal intensive care unit

To examine the effectiveness and cost of implementing a noise reduction protocol in a level III neonatal intensive care unit (NICU).

A prospective longitudinal study was done in a level III NICU, wherein a noise reduction protocol that included behavioral and environmental modification was implemented. The noise levels were measured sequentially every hour for 15 days before and after this intervention. The statistical significance of the reduction in noise levels after implementation of the protocol was tested by paired sample student's t-test. Cost was calculated using the generalized cost effectiveness model of the World Health Organisation. The present study has 80% power with 95% confidence to measure 2 dB differences between groups for the maximum recommended of 50 dB.

The protocol in the present study reduced noise levels in all the rooms of the NICU to within 60 dB with high statistical significance (p< 0.001). The extent of noise reduction in the rooms of the NICU was as follows: ventilator room by 9.58 dB (95% confidence interval: 6.73-12.42, p < 0.001), stable room by 6.54 dB (95% confidence interval: 2.92-4.16, p < 0.001), isolation room by 2.26 dB (95% confidence interval: 1.21-3.30, p < 0.001), pre-term room by 2.37 dB(95% confidence interval: 1.22-3.51, p < 0.001) and extreme preterm room by 2.09 dB (95% confidence interval: 1.14-3.02, p < 0.001). The intervention was most cost-effective in the ventilator room, requiring Rs. 81.09 to reduce 1 dB and least effective in the extreme pre-term room requiring Rs. 371.61 to reduce 1 dB.

The high efficacy and affordability of noise reduction protocols justify the need for implementation of these measures as a standard of care in neonatal intensive care units.