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Sound and vibration: effects on infants' heart rate and heart rate variability during neonatal transport
Björn-Markus Karlsson1, Marie Lindkvist, Markus Lindkvist
1Department of Clinical Sciences, Umeå University, Sweden. bjorn.karlsson@vll.se
Insights
Neonatal transport exposes infants to high sound and whole-body vibration levels, impacting heart rate. Earmuffs can reduce transport stress for infants.
Area of Science:
- Neonatal transport safety
- Pediatric critical care
- Environmental physiology
Background:
- Ambulance transport exposes infants to significant environmental stressors.
- Understanding the physiological impact of sound and vibration is crucial for neonatal care.
Purpose of the Study:
- To quantify the effects of sound and whole-body vibration on infant heart rate and variability during ambulance transport.
- To assess the impact of these stressors on physiological status.
Main Methods:
- ECG monitoring of heart rate and variability in 16 infants during air and ground ambulance transport.
- Measurement of whole-body vibration and sound levels during transport.
Main Results:
- Transport sound and vibration levels exceeded recommended limits.
- Higher vibration correlated with lower heart rate; higher sound correlated with higher heart rate.
- Infants wearing earmuffs exhibited lower heart rates, indicating a stress-reducing effect.
Conclusions:
- Neonatal transport environments often exceed safe sound and vibration levels.
- Sound appears to be a greater stressor than vibration for infants.
- Earmuffs are recommended to mitigate transport-related stress in neonates.
Aim:
To measure the effect of sound and whole-body vibration on infants' heart rate and heart rate variability during ground and air ambulance transport.
Methods:
Sixteen infants were transported by air ambulance with ground ambulance transport to and from the airports. Whole-body vibration and sound levels were recorded and heart parameters were obtained by ECG signal.
Results:
Sound and whole-body vibration levels exceeded the recommended limits. Mean whole-body vibration and sound levels were 0.19 m/s(2) and 73 dBA, respectively. Higher whole-body vibration was associated with a lower heart rate (p < 0.05), and higher sound level was linked to a higher heart rate (p = 0.05). The heart rate variability was significantly higher at the end of the transport than at the beginning (p < 0.01). Poorer physiological status was associated with lower heart rate variability (p < 0.001) and a lower heart rate (p < 0.01). Infants wearing earmuffs had a lower heart rate (p < 0.05).
Conclusions:
Sound and whole-body vibration during neonatal transport exceed recommended levels for adults, and sound seem to have a more stressful effect on the infant than vibrations. Infants should wear earmuffs during neonatal transport because of the stress-reducing effect.
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