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The effectiveness of earmuffs on the physiologic and behavioral stability in preterm infants
Nasrin Khalesi1, Nastaran Khosravi1, Azadeh Ranjbar2
1Ali Asghar Hospital, Iran University of Medical Sciences, Tehran, Iran.
Insights
Earmuffs significantly improve physiological stability and behavioral states in preterm infants by reducing neonatal intensive care unit (NICU) noise. This intervention enhances oxygen saturation and promotes better sleep patterns.
Area of Science:
- Neonatal care
- Auditory protection
- Infant physiology
Background:
- Neonatal intensive care units (NICUs) present high noise levels, potentially harming preterm infants.
- Earmuffs offer a protective measure against adverse noise effects in this vulnerable population.
Purpose of the Study:
- To evaluate the effectiveness of earmuffs in modulating the physiological and behavioral responses of preterm infants.
- To assess the impact of earmuff use on key health indicators in preterm neonates.
Main Methods:
- A crossover controlled trial involving 36 preterm infants in closed incubators.
- Infants alternated between wearing earmuffs and not wearing them over two consecutive days.
- Physiological parameters (heart rate, respiratory rate, oxygen saturation, blood pressure, body temperature) and behavioral states (Anderson Behavioral State Scoring system) were monitored.
Main Results:
- Earmuff use led to decreased heart and respiratory rates and increased arterial oxygen saturation (p < 0.05).
- Preterm infants using earmuffs exhibited lower Anderson Behavioral State Scoring (ABSS) scores, indicating improved behavioral states and lighter sleep (2.38 ± 0.47 vs. 4.8 ± 0.97, p < 0.05).
Conclusions:
- Earmuffs effectively reduce noise exposure in NICUs.
- The use of earmuffs enhances the physiological stability and improves the behavioral states of preterm neonates.
Background:
The use of earmuffs can protect preterm infants against negative effects of high noise levels in the neonatal intensive care unit. This study was aimed at assessing the effectiveness of the earmuffs on the physiologic and behavioral responses in preterm infants.
Methods:
A crossed over controlled trial was conducted at Aliasghar Hospital (Tehran, Iran) in 2014. Thirty-six preterm infants cared in closed incubators, 18 cases wore a pair of silicon earmuffs in the first day and the others were worn it at the second day. During 2 consecutive days, all subjects were observed as their own controls (without earmuffs). Physiologic (body temperature, heart rate, respiratory rate, systolic, diastolic pressures, arterial Oxygen Saturation) and behavioral responses (according to the Anderson behavioral state scoring system) were assessed every 2 h for 8 h long during daytime for two consecutive days.
Results:
The application of earmuffs could decrease the rate of the heart and respiratory while could increase the amount of oxygen saturation (p < 0.05). The results also showed that the preterm infants with earmuffs had lower ABSS score and a better light sleep compared to those without earmuffs (2.38 ± 0.47 versus 4.8 ± 0.97, p < 0.05).
Conclusion:
The results indicated that using the earmuffs reduces the level of noise in NICUs following by improving the preterm neonates' physiological stability and behavioral states of ABSS.

