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Published on: August 2, 2017
Quantification of cardio-respiratory interactions in healthy children during night-time sleep using joint symbolic
Muammar M Kabir1, Mark Kohler, Derek Abbott
1School of Electrical and Electronic Engineering, University of Adelaide, SA 5005, Australia. muammar.kabir@adelaide.edu.au
Insights
Healthy children show stronger cardio-respiratory interactions during slow-wave sleep. Joint symbolic dynamics effectively analyzes these connections, unaffected by age, gender, or BMI.
Area of Science:
- Cardiology
- Sleep Medicine
- Biomedical Engineering
Background:
- Cardio-respiratory interactions are crucial for physiological regulation during sleep.
- Understanding these interactions in children is vital for identifying potential health issues.
- Traditional methods may not fully capture the complex dynamics of heart rate and respiration.
Purpose of the Study:
- To investigate the relationship between R-R intervals and respiratory phases in healthy children during sleep.
- To apply a novel joint symbolic dynamics technique for analyzing cardio-respiratory interactions.
- To determine how sleep stages influence these interactions.
Main Methods:
- Utilized overnight polysomnography data from 40 healthy children.
- Extracted R-R interval time series from electrocardiograms (ECG).
- Obtained respiratory phases using the Hilbert transform from abdominal sensors.
- Transformed data into ternary symbol vectors and analyzed word correspondences for sleep stages.
Main Results:
- A significantly higher percentage of similarity was observed in joint symbolic dynamics during slow-wave (SW) sleep.
- This indicates a stronger cardio-respiratory interaction during SW sleep compared to other stages.
- No significant effect of age, gender, or Body Mass Index (BMI) on cardio-respiratory interaction was found.
Conclusions:
- Joint symbolic dynamics is a novel and efficient technique for analyzing cardio-respiratory interactions.
- Cardio-respiratory coupling varies significantly across different sleep stages in children.
- The findings provide new insights into sleep physiology and potential diagnostic tools.
Abstract:
The aim of this paper was to study interactions between R-R intervals and respiratory phases in healthy children during night-time sleep using a novel technique based on joint symbolic dynamics. We investigated overnight polysomnography data of 40 healthy children. The R-R time series were extracted from electrocardiograms (ECG) and respiratory phases were obtained from abdominal sensors using the Hilbert transform. Both the series were transformed into ternary symbol vectors based on the changes between two successive R-R intervals or respiratory phases, respectively. Subsequently, words of length '2' were formed and the correspondence between words of the two series for each sleep stage was determined to quantify cardio-respiratory interaction. We found a significantly higher percentage of similarity in the joint symbolic dynamics of R-R intervals and respiratory phases during slow-wave (SW) sleep compared to any other sleep stage. There was, however, no significant effect of age, gender or BMI on cardio-respiratory interaction. In conclusion, joint symbolic dynamics provides a novel efficient technique for the analysis of cardio-respiratory interaction.
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