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Ioannis Vogiatzis - One of the best experts on this subject based on the ideXlab platform.

  • high intensity exercise impairs extradiaphragmatic respiratory muscle perfusion in patients with copd
    Journal of Applied Physiology, 2021
    Co-Authors: Zafeiris Louvaris, Ioannis Vogiatzis, Antenor Rodrigues, Sauwaluk Dacha, Tin Gojevic, Wim Janssens, Rik Gosselink
    Abstract:

    We simultaneously assessed the blood flow index (BFI) in three respiratory muscles during Hyperpnea and high-intensity constant-load cycling sustained at comparable levels of work of breathing and ...

  • Differences in Respiratory Muscle Responses to Hyperpnea or Loaded Breathing in COPD.
    Medicine and science in sports and exercise, 2019
    Co-Authors: Antenor Rodrigues, Zafeiris Louvaris, Ioannis Vogiatzis, Sauwaluk Dacha, Wim Janssens, Rik Gosselink, Fabio Pitta, Daniel Langer
    Abstract:

    INTRODUCTION We aimed to compare acute mechanical and metabolic responses of the diaphragm and rib cage inspiratory muscles during two different types of respiratory loading in patients with chronic obstructive pulmonary disease. METHODS In 16 patients (age, 65 ± 13 yr; 56% male; forced expiratory volume in the first second, 60 ± 6%pred; maximum inspiratory pressure, 82 ± 5%pred), assessments of respiratory muscle EMG, esophageal pressure (Pes) and gastric pressures, breathing pattern, and noninvasive assessments of systemic (V˙O2, cardiac output, oxygen delivery and extraction) and respiratory muscle hemodynamic and oxygenation responses (blood flow index, oxygen delivery index, deoxyhemoglobin concentration, and tissues oxygen saturation [StiO2]), were performed during Hyperpnea and loaded breathing. RESULTS During Hyperpnea, breathing frequency, minute ventilation, esophageal and diaphragm pressure-time product per minute, cardiac output, and V˙O2 were higher than during loaded breathing (P 0.05). SCA-blood flow index and oxygen delivery index were lower, and SCA-deoxyhemoglobin concentration was higher during loaded breathing compared with Hyperpnea. Furthermore, SCA and intercostal muscle StiO2 were lower during loaded breathing compared with Hyperpnea (P < 0.05). CONCLUSION Greater inspiratory muscle effort during loaded breathing evoked larger rib cage and neck muscle activation compared with Hyperpnea. In addition, lower SCA and intercostal muscle StiO2 during loaded breathing compared with Hyperpnea indicates a mismatch between inspiratory muscle oxygen delivery and utilization induced by the former condition.

  • near infrared spectroscopy and indocyanine green derived blood flow index for noninvasive measurement of muscle perfusion during exercise in copd
    European Respiratory Journal, 2017
    Co-Authors: Zafeiris Louvaris, Helmut Habazettl, Spyros Zakynthinos, Harrieth Wagner, Peter D. Wagner, Ioannis Vogiatzis
    Abstract:

    Background: Near-infrared spectroscopy (NIRS) combined with the tracer indocyanine green dye (ICG) for minimally invasive measurement of the muscle blood flow index (BFI) has been validated in healthy, but there is no evidence about its validity in COPD. Aim: To investigate whether NIRS-ICG derived BFI (requiring only venous catheterization) reflects intra-individual changes in respiratory and locomotor muscle perfusion during exercise as reliably as muscle blood flow (MBF) (requiring both arterial and venous catherterization). Methods: Vastus lateralis MBF (calculated by the Fick principle and muscle ICG curve) and BFI (calculated only by muscle ICG curve) was simultaneously measured in 10 COPD (FEV1:51±6 %pred.) by NIRS at rest and during cycling at 25%, 50%, 75% and 100% of WRpeak, whilst for intercostal, MBF and BFI was measured during resting hyperpnoea trials at minute ventilation levels similar to those during exercise. Results: Vastus lateralis MBF and BFI increased progressively during cycling (from 2.8±0.4 to 39.7±7.0 ml/min/100gr and from 1.0±0.2 to 12.8±1.9 nM/s, respectively). Intercostal MBF and BFI increased with increasing minute ventilation during Hyperpnea (from 7.0±0.6 to 11.4±1.3 ml/min/100gr and from 2.5±0.3 to 4.5±0.7 nM/s, respectively). Correlation coefficient analyses between individual BFI and MBF values revealed strong agreement for both quadriceps (r=0.831, p Conclusion: NIRS-ICG derived BFI is less invassive, less technically demanding and valid surrogate index for assessing respiratory and locomotor muscle perfusion form rest to maximal exercise in COPD.

  • intercostal muscle blood flow limitation during exercise in chronic obstructive pulmonary disease
    American Journal of Respiratory and Critical Care Medicine, 2010
    Co-Authors: Ioannis Vogiatzis, Zafeiris Louvaris, Evgenia Cherouveim, Helmut Habazettl, Dimitris Athanasopoulos, Andrea Aliverti, Harrieth Wagner, Charis Roussos, Peter D. Wagner, Spyros Zakynthinos
    Abstract:

    Rationale: It has been hypothesized that, because of the high work of breathing sustained by patients with chronic obstructive pulmonary disease (COPD) during exercise, blood flow may increase in favor of the respiratory muscles, thereby compromising locomotor muscle blood flow.Objectives: To test this hypothesis by investigating whether, at the same work of breathing, intercostal muscle blood flow during exercise is as high as during resting isocapnic Hyperpnea when respiratory and locomotor muscles do not compete for the available blood flow.Methods: Intercostal and vastus lateralis muscle perfusion was measured simultaneously in 10 patients with COPD (FEV1 = 50.5 ± 5.5% predicted) by near-infrared spectroscopy using indocyanine green dye.Measurements and Main Results: Measurements were made at several exercise intensities up to peak work rate (WRpeak) and subsequently during resting Hyperpnea at minute ventilation levels up to those at WRpeak. During resting Hyperpnea, intercostal muscle blood flow inc...

Antenor Rodrigues - One of the best experts on this subject based on the ideXlab platform.

  • high intensity exercise impairs extradiaphragmatic respiratory muscle perfusion in patients with copd
    Journal of Applied Physiology, 2021
    Co-Authors: Zafeiris Louvaris, Ioannis Vogiatzis, Antenor Rodrigues, Sauwaluk Dacha, Tin Gojevic, Wim Janssens, Rik Gosselink
    Abstract:

    We simultaneously assessed the blood flow index (BFI) in three respiratory muscles during Hyperpnea and high-intensity constant-load cycling sustained at comparable levels of work of breathing and ...

  • Differences in Respiratory Muscle Responses to Hyperpnea or Loaded Breathing in COPD.
    Medicine and science in sports and exercise, 2019
    Co-Authors: Antenor Rodrigues, Zafeiris Louvaris, Ioannis Vogiatzis, Sauwaluk Dacha, Wim Janssens, Rik Gosselink, Fabio Pitta, Daniel Langer
    Abstract:

    INTRODUCTION We aimed to compare acute mechanical and metabolic responses of the diaphragm and rib cage inspiratory muscles during two different types of respiratory loading in patients with chronic obstructive pulmonary disease. METHODS In 16 patients (age, 65 ± 13 yr; 56% male; forced expiratory volume in the first second, 60 ± 6%pred; maximum inspiratory pressure, 82 ± 5%pred), assessments of respiratory muscle EMG, esophageal pressure (Pes) and gastric pressures, breathing pattern, and noninvasive assessments of systemic (V˙O2, cardiac output, oxygen delivery and extraction) and respiratory muscle hemodynamic and oxygenation responses (blood flow index, oxygen delivery index, deoxyhemoglobin concentration, and tissues oxygen saturation [StiO2]), were performed during Hyperpnea and loaded breathing. RESULTS During Hyperpnea, breathing frequency, minute ventilation, esophageal and diaphragm pressure-time product per minute, cardiac output, and V˙O2 were higher than during loaded breathing (P 0.05). SCA-blood flow index and oxygen delivery index were lower, and SCA-deoxyhemoglobin concentration was higher during loaded breathing compared with Hyperpnea. Furthermore, SCA and intercostal muscle StiO2 were lower during loaded breathing compared with Hyperpnea (P < 0.05). CONCLUSION Greater inspiratory muscle effort during loaded breathing evoked larger rib cage and neck muscle activation compared with Hyperpnea. In addition, lower SCA and intercostal muscle StiO2 during loaded breathing compared with Hyperpnea indicates a mismatch between inspiratory muscle oxygen delivery and utilization induced by the former condition.

Zafeiris Louvaris - One of the best experts on this subject based on the ideXlab platform.

  • high intensity exercise impairs extradiaphragmatic respiratory muscle perfusion in patients with copd
    Journal of Applied Physiology, 2021
    Co-Authors: Zafeiris Louvaris, Ioannis Vogiatzis, Antenor Rodrigues, Sauwaluk Dacha, Tin Gojevic, Wim Janssens, Rik Gosselink
    Abstract:

    We simultaneously assessed the blood flow index (BFI) in three respiratory muscles during Hyperpnea and high-intensity constant-load cycling sustained at comparable levels of work of breathing and ...

  • Differences in Respiratory Muscle Responses to Hyperpnea or Loaded Breathing in COPD.
    Medicine and science in sports and exercise, 2019
    Co-Authors: Antenor Rodrigues, Zafeiris Louvaris, Ioannis Vogiatzis, Sauwaluk Dacha, Wim Janssens, Rik Gosselink, Fabio Pitta, Daniel Langer
    Abstract:

    INTRODUCTION We aimed to compare acute mechanical and metabolic responses of the diaphragm and rib cage inspiratory muscles during two different types of respiratory loading in patients with chronic obstructive pulmonary disease. METHODS In 16 patients (age, 65 ± 13 yr; 56% male; forced expiratory volume in the first second, 60 ± 6%pred; maximum inspiratory pressure, 82 ± 5%pred), assessments of respiratory muscle EMG, esophageal pressure (Pes) and gastric pressures, breathing pattern, and noninvasive assessments of systemic (V˙O2, cardiac output, oxygen delivery and extraction) and respiratory muscle hemodynamic and oxygenation responses (blood flow index, oxygen delivery index, deoxyhemoglobin concentration, and tissues oxygen saturation [StiO2]), were performed during Hyperpnea and loaded breathing. RESULTS During Hyperpnea, breathing frequency, minute ventilation, esophageal and diaphragm pressure-time product per minute, cardiac output, and V˙O2 were higher than during loaded breathing (P 0.05). SCA-blood flow index and oxygen delivery index were lower, and SCA-deoxyhemoglobin concentration was higher during loaded breathing compared with Hyperpnea. Furthermore, SCA and intercostal muscle StiO2 were lower during loaded breathing compared with Hyperpnea (P < 0.05). CONCLUSION Greater inspiratory muscle effort during loaded breathing evoked larger rib cage and neck muscle activation compared with Hyperpnea. In addition, lower SCA and intercostal muscle StiO2 during loaded breathing compared with Hyperpnea indicates a mismatch between inspiratory muscle oxygen delivery and utilization induced by the former condition.

  • near infrared spectroscopy and indocyanine green derived blood flow index for noninvasive measurement of muscle perfusion during exercise in copd
    European Respiratory Journal, 2017
    Co-Authors: Zafeiris Louvaris, Helmut Habazettl, Spyros Zakynthinos, Harrieth Wagner, Peter D. Wagner, Ioannis Vogiatzis
    Abstract:

    Background: Near-infrared spectroscopy (NIRS) combined with the tracer indocyanine green dye (ICG) for minimally invasive measurement of the muscle blood flow index (BFI) has been validated in healthy, but there is no evidence about its validity in COPD. Aim: To investigate whether NIRS-ICG derived BFI (requiring only venous catheterization) reflects intra-individual changes in respiratory and locomotor muscle perfusion during exercise as reliably as muscle blood flow (MBF) (requiring both arterial and venous catherterization). Methods: Vastus lateralis MBF (calculated by the Fick principle and muscle ICG curve) and BFI (calculated only by muscle ICG curve) was simultaneously measured in 10 COPD (FEV1:51±6 %pred.) by NIRS at rest and during cycling at 25%, 50%, 75% and 100% of WRpeak, whilst for intercostal, MBF and BFI was measured during resting hyperpnoea trials at minute ventilation levels similar to those during exercise. Results: Vastus lateralis MBF and BFI increased progressively during cycling (from 2.8±0.4 to 39.7±7.0 ml/min/100gr and from 1.0±0.2 to 12.8±1.9 nM/s, respectively). Intercostal MBF and BFI increased with increasing minute ventilation during Hyperpnea (from 7.0±0.6 to 11.4±1.3 ml/min/100gr and from 2.5±0.3 to 4.5±0.7 nM/s, respectively). Correlation coefficient analyses between individual BFI and MBF values revealed strong agreement for both quadriceps (r=0.831, p Conclusion: NIRS-ICG derived BFI is less invassive, less technically demanding and valid surrogate index for assessing respiratory and locomotor muscle perfusion form rest to maximal exercise in COPD.

  • intercostal muscle blood flow limitation during exercise in chronic obstructive pulmonary disease
    American Journal of Respiratory and Critical Care Medicine, 2010
    Co-Authors: Ioannis Vogiatzis, Zafeiris Louvaris, Evgenia Cherouveim, Helmut Habazettl, Dimitris Athanasopoulos, Andrea Aliverti, Harrieth Wagner, Charis Roussos, Peter D. Wagner, Spyros Zakynthinos
    Abstract:

    Rationale: It has been hypothesized that, because of the high work of breathing sustained by patients with chronic obstructive pulmonary disease (COPD) during exercise, blood flow may increase in favor of the respiratory muscles, thereby compromising locomotor muscle blood flow.Objectives: To test this hypothesis by investigating whether, at the same work of breathing, intercostal muscle blood flow during exercise is as high as during resting isocapnic Hyperpnea when respiratory and locomotor muscles do not compete for the available blood flow.Methods: Intercostal and vastus lateralis muscle perfusion was measured simultaneously in 10 patients with COPD (FEV1 = 50.5 ± 5.5% predicted) by near-infrared spectroscopy using indocyanine green dye.Measurements and Main Results: Measurements were made at several exercise intensities up to peak work rate (WRpeak) and subsequently during resting Hyperpnea at minute ventilation levels up to those at WRpeak. During resting Hyperpnea, intercostal muscle blood flow inc...

Rik Gosselink - One of the best experts on this subject based on the ideXlab platform.

  • high intensity exercise impairs extradiaphragmatic respiratory muscle perfusion in patients with copd
    Journal of Applied Physiology, 2021
    Co-Authors: Zafeiris Louvaris, Ioannis Vogiatzis, Antenor Rodrigues, Sauwaluk Dacha, Tin Gojevic, Wim Janssens, Rik Gosselink
    Abstract:

    We simultaneously assessed the blood flow index (BFI) in three respiratory muscles during Hyperpnea and high-intensity constant-load cycling sustained at comparable levels of work of breathing and ...

  • Differences in Respiratory Muscle Responses to Hyperpnea or Loaded Breathing in COPD.
    Medicine and science in sports and exercise, 2019
    Co-Authors: Antenor Rodrigues, Zafeiris Louvaris, Ioannis Vogiatzis, Sauwaluk Dacha, Wim Janssens, Rik Gosselink, Fabio Pitta, Daniel Langer
    Abstract:

    INTRODUCTION We aimed to compare acute mechanical and metabolic responses of the diaphragm and rib cage inspiratory muscles during two different types of respiratory loading in patients with chronic obstructive pulmonary disease. METHODS In 16 patients (age, 65 ± 13 yr; 56% male; forced expiratory volume in the first second, 60 ± 6%pred; maximum inspiratory pressure, 82 ± 5%pred), assessments of respiratory muscle EMG, esophageal pressure (Pes) and gastric pressures, breathing pattern, and noninvasive assessments of systemic (V˙O2, cardiac output, oxygen delivery and extraction) and respiratory muscle hemodynamic and oxygenation responses (blood flow index, oxygen delivery index, deoxyhemoglobin concentration, and tissues oxygen saturation [StiO2]), were performed during Hyperpnea and loaded breathing. RESULTS During Hyperpnea, breathing frequency, minute ventilation, esophageal and diaphragm pressure-time product per minute, cardiac output, and V˙O2 were higher than during loaded breathing (P 0.05). SCA-blood flow index and oxygen delivery index were lower, and SCA-deoxyhemoglobin concentration was higher during loaded breathing compared with Hyperpnea. Furthermore, SCA and intercostal muscle StiO2 were lower during loaded breathing compared with Hyperpnea (P < 0.05). CONCLUSION Greater inspiratory muscle effort during loaded breathing evoked larger rib cage and neck muscle activation compared with Hyperpnea. In addition, lower SCA and intercostal muscle StiO2 during loaded breathing compared with Hyperpnea indicates a mismatch between inspiratory muscle oxygen delivery and utilization induced by the former condition.

Sauwaluk Dacha - One of the best experts on this subject based on the ideXlab platform.

  • high intensity exercise impairs extradiaphragmatic respiratory muscle perfusion in patients with copd
    Journal of Applied Physiology, 2021
    Co-Authors: Zafeiris Louvaris, Ioannis Vogiatzis, Antenor Rodrigues, Sauwaluk Dacha, Tin Gojevic, Wim Janssens, Rik Gosselink
    Abstract:

    We simultaneously assessed the blood flow index (BFI) in three respiratory muscles during Hyperpnea and high-intensity constant-load cycling sustained at comparable levels of work of breathing and ...

  • Differences in Respiratory Muscle Responses to Hyperpnea or Loaded Breathing in COPD.
    Medicine and science in sports and exercise, 2019
    Co-Authors: Antenor Rodrigues, Zafeiris Louvaris, Ioannis Vogiatzis, Sauwaluk Dacha, Wim Janssens, Rik Gosselink, Fabio Pitta, Daniel Langer
    Abstract:

    INTRODUCTION We aimed to compare acute mechanical and metabolic responses of the diaphragm and rib cage inspiratory muscles during two different types of respiratory loading in patients with chronic obstructive pulmonary disease. METHODS In 16 patients (age, 65 ± 13 yr; 56% male; forced expiratory volume in the first second, 60 ± 6%pred; maximum inspiratory pressure, 82 ± 5%pred), assessments of respiratory muscle EMG, esophageal pressure (Pes) and gastric pressures, breathing pattern, and noninvasive assessments of systemic (V˙O2, cardiac output, oxygen delivery and extraction) and respiratory muscle hemodynamic and oxygenation responses (blood flow index, oxygen delivery index, deoxyhemoglobin concentration, and tissues oxygen saturation [StiO2]), were performed during Hyperpnea and loaded breathing. RESULTS During Hyperpnea, breathing frequency, minute ventilation, esophageal and diaphragm pressure-time product per minute, cardiac output, and V˙O2 were higher than during loaded breathing (P 0.05). SCA-blood flow index and oxygen delivery index were lower, and SCA-deoxyhemoglobin concentration was higher during loaded breathing compared with Hyperpnea. Furthermore, SCA and intercostal muscle StiO2 were lower during loaded breathing compared with Hyperpnea (P < 0.05). CONCLUSION Greater inspiratory muscle effort during loaded breathing evoked larger rib cage and neck muscle activation compared with Hyperpnea. In addition, lower SCA and intercostal muscle StiO2 during loaded breathing compared with Hyperpnea indicates a mismatch between inspiratory muscle oxygen delivery and utilization induced by the former condition.