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Published on: January 27, 2023
Multi-lag tone-entropy in neonatal stress
Matej Šapina1,2,3, Chandan Kumar Karmakar4,5, Karolina Kramarić6,2,3
1University hospital Osijek, Pediatric Clinic, J. Huttlera 4, 31000 Osijek, Croatia sapina.matej@yahoo.com.
This study shows that multi-lag tone-entropy (T-E) analysis can objectively assess neonatal stress. Higher entropy and lower tone during stress indicate changes in autonomic activity, improving stress detection in newborns.
Area of Science:
- Neonatal physiology
- Autonomic nervous system function
- Nonlinear time series analysis
Background:
- Heart rate variability (HRV) analysis traditionally uses linear methods.
- Nonlinear methods offer deeper insights into complex physiological systems like HRV.
- Neonatal stress assessment requires objective, sensitive measures.
Purpose of the Study:
- To evaluate the efficacy of multi-lag tone-entropy (T-E) analysis for assessing neonatal stress.
- To investigate the influence of external stressors on HRV parameters in term neonates.
- To determine the diagnostic performance of T-E analysis in distinguishing stress and resting states.
Main Methods:
- Applied multi-lag T-E analysis to heart rate variability (HRV) data from 40 healthy term neonates.
- Collected HRV data during resting, heel stimulation, and heel stick blood drawing phases.
- Utilized Receiver Operating Characteristic (ROC) analysis to assess diagnostic performance of tone and entropy.
Main Results:
- Stressed neonates exhibited higher mean entropy and lower mean tone, indicating reduced randomness and altered autonomic activity (sympathetic increase, parasympathetic decrease).
- Tone analysis alone showed better performance than entropy in distinguishing resting from stress phases.
- A combined quadratic linear regression model of tone and entropy achieved high accuracy in differentiating resting from stress states.
Conclusions:
- Multi-lag T-E analysis is a promising tool for objective neonatal stress assessment.
- The combination of tone and entropy provides a robust measure for detecting stress in neonates.
- This method offers potential for improved clinical monitoring of neonatal well-being during stressful procedures.
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