TY  - JOUR
AU  - Kalauzi, Aleksandar
AU  - Matić, Zoran
AU  - Platiša, Mirjana M.
AU  - Bojić, Tijana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10708
AB  - Due to the fact that respiratory breath-to-breath and cardiac intervals between two successive R peaks (BBI and RRI, respectively) are not temporally concurrent, in a previous paper, we proposed a method to calculate both the integer and non-integer parts of the pulse respiration quotient (PRQ = BBI/RRI = PRQint + b1 + b2), b1 and b2 being parts of the border RRIs for each BBI. In this work, we study the correlations between BBI and PRQ, as well as those between BBI and mean RRI within each BBI (mRRI), on a group of twenty subjects in four conditions: in supine and standing positions, in combination with spontaneous and slow breathing. Results show that the BBI vs. PRQ correlations are positive; whereas the breathing regime had little or no effect on the linear regression slopes, body posture did. Two types of scatter plots were obtained with the BBI vs. mRRI correlations: one showed points aggregated around the concurrent PRQint lines, while the other showed randomly distributed points. Five out of six of the proposed aggregation measures confirmed the existence of these two cardio-respiratory coupling regimes. We also used b1 to study the positions of R pulses relative to the respiration onsets and showed that they were more synchronous with sympathetic activation. Overall, this method should be used in different pathological states.
T2  - Bioengineering
T1  - Two Operational Modes of Cardio-Respiratory Coupling Revealed by Pulse-Respiration Quotient
VL  - 10
IS  - 2
SP  - 180
DO  - 10.3390/bioengineering10020180
ER  - 

@article{
author = "Kalauzi, Aleksandar and Matić, Zoran and Platiša, Mirjana M. and Bojić, Tijana",
year = "2023",
abstract = "Due to the fact that respiratory breath-to-breath and cardiac intervals between two successive R peaks (BBI and RRI, respectively) are not temporally concurrent, in a previous paper, we proposed a method to calculate both the integer and non-integer parts of the pulse respiration quotient (PRQ = BBI/RRI = PRQint + b1 + b2), b1 and b2 being parts of the border RRIs for each BBI. In this work, we study the correlations between BBI and PRQ, as well as those between BBI and mean RRI within each BBI (mRRI), on a group of twenty subjects in four conditions: in supine and standing positions, in combination with spontaneous and slow breathing. Results show that the BBI vs. PRQ correlations are positive; whereas the breathing regime had little or no effect on the linear regression slopes, body posture did. Two types of scatter plots were obtained with the BBI vs. mRRI correlations: one showed points aggregated around the concurrent PRQint lines, while the other showed randomly distributed points. Five out of six of the proposed aggregation measures confirmed the existence of these two cardio-respiratory coupling regimes. We also used b1 to study the positions of R pulses relative to the respiration onsets and showed that they were more synchronous with sympathetic activation. Overall, this method should be used in different pathological states.",
journal = "Bioengineering",
title = "Two Operational Modes of Cardio-Respiratory Coupling Revealed by Pulse-Respiration Quotient",
volume = "10",
number = "2",
pages = "180",
doi = "10.3390/bioengineering10020180"
}

Kalauzi, A., Matić, Z., Platiša, M. M.,& Bojić, T.. (2023). Two Operational Modes of Cardio-Respiratory Coupling Revealed by Pulse-Respiration Quotient. in Bioengineering, 10(2), 180.
https://doi.org/10.3390/bioengineering10020180

Kalauzi A, Matić Z, Platiša MM, Bojić T. Two Operational Modes of Cardio-Respiratory Coupling Revealed by Pulse-Respiration Quotient. in Bioengineering. 2023;10(2):180.
doi:10.3390/bioengineering10020180 .

Kalauzi, Aleksandar, Matić, Zoran, Platiša, Mirjana M., Bojić, Tijana, "Two Operational Modes of Cardio-Respiratory Coupling Revealed by Pulse-Respiration Quotient" in Bioengineering, 10, no. 2 (2023):180,
https://doi.org/10.3390/bioengineering10020180 . .

TY  - JOUR
AU  - Matić, Zoran
AU  - Kalauzi, Aleksandar
AU  - Moser, Maximilian
AU  - Platiša, Mirjana M.
AU  - Lazarević, Mihailo
AU  - Bojić, Tijana
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10599
AB  - In this research we explored the (homeo)dynamic character of cardiorespiratory coupling (CRC) under the influence of different body posture and breathing regimes. Our tool for it was the pulse respiration quotient (PRQ), representing the number of heartbeat intervals per breathing cycle. We obtained non-integer PRQ values using our advanced Matlab® algorithm and applied it on the signals of 20 healthy subjects in four conditions: supine position with spontaneous breathing (Supin), standing with spontaneous breathing (Stand), supine position with slow (0.1 Hz) breathing (Supin01) and standing with slow (0.1 Hz) breathing (Stand01).Main results: Linear features of CRC (in PRQ signals) were dynamically very sensitive to posture and breathing rhythm perturbations. There are obvious increases in PRQ mean level and variability under the separated and joined influence of orthostasis and slow (0.1 Hz) breathing. This increase was most pronounced in Stand01 as the state of joint influences. Importantly, PRQ dynamic modification showed greater sensitivity to body posture and breathing regime changes than mean value and standard deviation of heart rhythm and breathing rhythm. In addition, as a consequence of prolonged supine position, we noticed the tendency to integer quantization of PRQ (especially after 14 min), in which the most common quantization number was 4:1 (demonstrated in other research reports as well). In orthostasis and slow breathing, quantization can also be observed, but shifted to other values. We postulate that these results manifest resonance effects induced by coupling patterns from sympathetic and parasympathetic adjustments (with the second as dominant factor).Significance: Our research confirms that cardiorespiratory coupling adaptability could be profoundly explored by precisely calculated PRQ parameter since cardiorespiratory regulation in healthy subjects is characterized by a high level of autonomic adaptability (responsiveness) to posture and breathing regime, although comparisons with pathological states has yet to be performed. We found Stand01 to be the most provoking state for the dynamic modification of PRQ (cardiorespiratory inducement). As such, Stand01 has the potential of using for PRQ tuning by conditioning the cardiorespiratory autonomic neural networks, e.g., in the cases where PRQ is disturbed by environmental (i.e., microgravity) or pathologic conditions.
T2  - Frontiers in Physiology
T1  - Pulse respiration quotient as a measure sensitive to changes in dynamic behavior of cardiorespiratory coupling such as body posture and breathing regime
VL  - 13
DO  - 10.3389/fphys.2022.946613
ER  - 

@article{
author = "Matić, Zoran and Kalauzi, Aleksandar and Moser, Maximilian and Platiša, Mirjana M. and Lazarević, Mihailo and Bojić, Tijana",
year = "2022",
abstract = "In this research we explored the (homeo)dynamic character of cardiorespiratory coupling (CRC) under the influence of different body posture and breathing regimes. Our tool for it was the pulse respiration quotient (PRQ), representing the number of heartbeat intervals per breathing cycle. We obtained non-integer PRQ values using our advanced Matlab® algorithm and applied it on the signals of 20 healthy subjects in four conditions: supine position with spontaneous breathing (Supin), standing with spontaneous breathing (Stand), supine position with slow (0.1 Hz) breathing (Supin01) and standing with slow (0.1 Hz) breathing (Stand01).Main results: Linear features of CRC (in PRQ signals) were dynamically very sensitive to posture and breathing rhythm perturbations. There are obvious increases in PRQ mean level and variability under the separated and joined influence of orthostasis and slow (0.1 Hz) breathing. This increase was most pronounced in Stand01 as the state of joint influences. Importantly, PRQ dynamic modification showed greater sensitivity to body posture and breathing regime changes than mean value and standard deviation of heart rhythm and breathing rhythm. In addition, as a consequence of prolonged supine position, we noticed the tendency to integer quantization of PRQ (especially after 14 min), in which the most common quantization number was 4:1 (demonstrated in other research reports as well). In orthostasis and slow breathing, quantization can also be observed, but shifted to other values. We postulate that these results manifest resonance effects induced by coupling patterns from sympathetic and parasympathetic adjustments (with the second as dominant factor).Significance: Our research confirms that cardiorespiratory coupling adaptability could be profoundly explored by precisely calculated PRQ parameter since cardiorespiratory regulation in healthy subjects is characterized by a high level of autonomic adaptability (responsiveness) to posture and breathing regime, although comparisons with pathological states has yet to be performed. We found Stand01 to be the most provoking state for the dynamic modification of PRQ (cardiorespiratory inducement). As such, Stand01 has the potential of using for PRQ tuning by conditioning the cardiorespiratory autonomic neural networks, e.g., in the cases where PRQ is disturbed by environmental (i.e., microgravity) or pathologic conditions.",
journal = "Frontiers in Physiology",
title = "Pulse respiration quotient as a measure sensitive to changes in dynamic behavior of cardiorespiratory coupling such as body posture and breathing regime",
volume = "13",
doi = "10.3389/fphys.2022.946613"
}

Matić, Z., Kalauzi, A., Moser, M., Platiša, M. M., Lazarević, M.,& Bojić, T.. (2022). Pulse respiration quotient as a measure sensitive to changes in dynamic behavior of cardiorespiratory coupling such as body posture and breathing regime. in Frontiers in Physiology, 13.
https://doi.org/10.3389/fphys.2022.946613

Matić Z, Kalauzi A, Moser M, Platiša MM, Lazarević M, Bojić T. Pulse respiration quotient as a measure sensitive to changes in dynamic behavior of cardiorespiratory coupling such as body posture and breathing regime. in Frontiers in Physiology. 2022;13.
doi:10.3389/fphys.2022.946613 .

Matić, Zoran, Kalauzi, Aleksandar, Moser, Maximilian, Platiša, Mirjana M., Lazarević, Mihailo, Bojić, Tijana, "Pulse respiration quotient as a measure sensitive to changes in dynamic behavior of cardiorespiratory coupling such as body posture and breathing regime" in Frontiers in Physiology, 13 (2022),
https://doi.org/10.3389/fphys.2022.946613 . .