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Dirkjan Slebos - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Multiple Diagnostic Tests to Measure Dynamic Hyperinflation in Patients with Severe Emphysema Treated with Endobronchial Coils
Lung, 2021Co-Authors: Marlies Van Dijk, Karin Klooster, Jorine E Hartman, Sonja W. S. Augustijn, Nick H. T. Ten Hacken, Dirkjan SlebosAbstract:Purpose For this study, we aimed to compare Dynamic Hyperinflation measured by cardiopulmonary exercise testing (CPET), a six-minute walking test (6-MWT), and a manually paced tachypnea test (MPT) in patients with severe emphysema who were treated with endobronchial coils. Additionally, we investigated whether Dynamic Hyperinflation changed after treatment with endobronchial coils. Methods Dynamic Hyperinflation was measured with CPET, 6-MWT, and an MPT in 29 patients before and after coil treatment. Results There was no significant change in Dynamic Hyperinflation after treatment with coils. Comparison of CPET and MPT showed a strong association (rho 0.660, p
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change in Dynamic Hyperinflation after bronchoscopic lung volume reduction in patients with emphysema
Lung, 2020Co-Authors: Marlies Van Dijk, Karin Klooster, Jorine E Hartman, Nick Ten H T Hacken, Dirkjan SlebosAbstract:In patients with severe emphysema, Dynamic Hyperinflation is superimposed on top of already existing static Hyperinflation. Static Hyperinflation reduces significantly after bronchoscopic lung volume reduction (BLVR). In this study, we investigated the effect of BLVR compared to standard of care (SoC) on Dynamic Hyperinflation. Dynamic Hyperinflation was induced by a manually paced tachypnea test (MPT) and was defined by change in inspiratory capacity (IC) measured before and after MPT. Static and Dynamic Hyperinflation measurements were performed both at baseline and 6 months after BLVR with endobronchial valves or coils (treatment group) or SoC (control group). Eighteen patients underwent BLVR (78% female, 57 (43–67) years, FEV1 25(18–37) %predicted, residual volume 231 (182–376) %predicted). Thirteen patients received SoC (100% female, 59 (44–74) years, FEV1 25 (19–37) %predicted, residual volume 225 (152–279) %predicted. The 6 months median change in Dynamic Hyperinflation in the treatment group was: + 225 ml (range − 113 to + 803) (p < 0.01) vs 0 ml (− 1067 to + 500) in the control group (p = 0.422). An increase in Dynamic Hyperinflation was significantly associated with a decrease in residual volume (r = − 0.439, p < 0.01). Bronchoscopic lung volume reduction increases the ability for Dynamic Hyperinflation in patients with severe emphysema. We propose this is a consequence of improved static Hyperinflation.
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Change in Dynamic Hyperinflation After Bronchoscopic Lung Volume Reduction in Patients with Emphysema
Lung, 2020Co-Authors: Marlies Van Dijk, Karin Klooster, Jorine E Hartman, Nick Ten H T Hacken, Dirkjan SlebosAbstract:Background and Purpose In patients with severe emphysema, Dynamic Hyperinflation is superimposed on top of already existing static Hyperinflation. Static Hyperinflation reduces significantly after bronchoscopic lung volume reduction (BLVR). In this study, we investigated the effect of BLVR compared to standard of care (SoC) on Dynamic Hyperinflation. Methods Dynamic Hyperinflation was induced by a manually paced tachypnea test (MPT) and was defined by change in inspiratory capacity (IC) measured before and after MPT. Static and Dynamic Hyperinflation measurements were performed both at baseline and 6 months after BLVR with endobronchial valves or coils (treatment group) or SoC (control group). Results Eighteen patients underwent BLVR (78% female, 57 (43–67) years, FEV_1 25(18–37) %predicted, residual volume 231 (182–376) %predicted). Thirteen patients received SoC (100% female, 59 (44–74) years, FEV_1 25 (19–37) %predicted, residual volume 225 (152–279) %predicted. The 6 months median change in Dynamic Hyperinflation in the treatment group was: + 225 ml (range − 113 to + 803) ( p
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determining the role of Dynamic Hyperinflation in patients with severe chronic obstructive pulmonary disease
Respiration, 2015Co-Authors: Karin Klooster, Jorine E Hartman, Nick Ten H T Hacken, Frank C Sciurba, Huib A M Kerstjens, Dirkjan SlebosAbstract:Background: Dynamic Hyperinflation due to increased respiratory frequency during exercise is associated with limitations in exercise capacity in patients with moderately severe chronic obstructive pulmonary disease (COPD). Objectives: The present study assessed whether the manually paced tachypnea (MPT) test, sitting at rest, induces Dynamic Hyperinflation correlating with exercise capacity in patients with very severe COPD. Methods: Dynamic Hyperinflation was induced by the MPT test, using a breathing frequency of 40/min for 1 min. Dynamic Hyperinflation was defined as a ‘change' in inspiratory capacity (IC) before and directly after the MPT test. At baseline, static Hyperinflation by body plethysmography was measured, as well as the 6-min walking test and spirometry. Results: We studied 74 patients with severe COPD (age 59 ± 9 years, FEV1 28 ± 10% predicted). All patients tolerated the MPT test well. It induced a significant decrease in IC: -0.65 ± 0.33 liters, p Conclusions: In patients with very severe COPD, Dynamic Hyperinflation measurement by the MPT test is feasible and contributes less importantly to exercise performance than static Hyperinflation.
Yvonne F Heijdra - One of the best experts on this subject based on the ideXlab platform.
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Resting and ADL-induced Dynamic Hyperinflation explain physical inactivity in COPD better than FEV1
Respiratory Medicine, 2013Co-Authors: Anke Lahaije, Hanneke A.c. Van Helvoort, P. N. Richard Dekhuijzen, J H M M Vercoulen, Yvonne F HeijdraAbstract:Summary Background Physical activity and health status deteriorate early in the course of chronic obstructive pulmonary disease (COPD). This can only partially be explained by the degree of airflow limitation. Changes in (resting and Dynamic) lung volumes are known to be associated with functional impairments and thus might influence physical activity level. The aim of the present cross-sectional study was to explore the contribution of Dynamic Hyperinflation during daily life activities (ADL) in the decline in physical activity. Methods Airflow limitation and inspiratory capacity at rest to total lung capacity ratio (IC/TLC) as a measure of resting Hyperinflation were measured in 59 patients with COPD (GOLD I–IV). Mean daily physical activity was assessed with a tri-axial accelerometer. Measurements of Dynamic Hyperinflation during ADL (ΔIC and inspiratory reserve volume at end ADL) were performed at patients' home using a portable breath-by-breath system. Results Multiple regression analysis showed that resting as well as ADL-induced Dynamic Hyperinflation independently contributed to decreased daily physical activity, together explaining 45.8% of the variance in physical activity. In contrast to Hyperinflation, the severity of airflow limitation (FEV 1 ) appeared to have no unique part in explaining how physically (in-) active patients were. Conclusions The presence of resting Hyperinflation and occurrence of Dynamic Hyperinflation during ADL contribute to reduced physical activity levels in patients with COPD, independently of the degree of airflow limitation.
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diagnostic accuracy of metronome paced tachypnea to detect Dynamic Hyperinflation
Clinical Physiology and Functional Imaging, 2013Co-Authors: Anke Lahaije, Laura Willems, Hieronymus W H Van Hees, P Richard N Dekhuijze, Hanneke Van Helvoo, Yvonne F HeijdraAbstract:INTRODUCTION: This prospective study was carried out to investigate if metronome-paced tachypnea (MPT) can serve as an accurate diagnostic tool to identify patients with chronic obstructive pulmonary disease (COPD) who are susceptible to develop Dynamic Hyperinflation during exercise. Commonly, this is assessed by measuring change in inspiratory capacity (IC) during cardiopulmonary exercise testing (CPET), which, however, is complex and laborious. METHODS: Fifty-three patients with COPD (FEV(1) 58 +/- 22%pred) and 20 age-matched healthy subjects were characterized by lung function testing and performed CPET (reference standard) and MPT. The repeatability coefficient of IC (10.2%) was used as cut-off to classify subjects as hyperinflators during CPET. Subsequently, Dynamic Hyperinflation was measured after MPT. With receiver operating characteristic analysis, the optimal cut-off for MPT-induced Dynamic Hyperinflation was determined and sensitivity and specificity of MPT to identify hyperinflators were evaluated. RESULTS: With 10.2% decrease in IC as cut-off for CPET-induced Dynamic Hyperinflation, the optimal cut-off for MPT was 11.1% decrease in IC. Using these cut-offs, MPT had a sensitivity of 85% and specificity of 85% to identify the subjects who hyperinflated during CPET. CONCLUSIONS: The MPT test shows good overall accuracy to identify subjects who are susceptible to develop Dynamic Hyperinflation during CPET. Before considering the use of MPT as a screening tool for Dynamic Hyperinflation in COPD, sensitivity and specificity need further evaluation.
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Similar Dynamic Hyperinflation during arm and leg exercise at similar ventilation in chronic obstructive pulmonary disease.
Medicine and science in sports and exercise, 2011Co-Authors: Jorien D. C. Hannink, P. N. Richard Dekhuijzen, Hanneke Van Helvoort, Yvonne F HeijdraAbstract:PURPOSE: Patients with chronic obstructive pulmonary disease (COPD) report more dyspnea during arm than during leg exercise. One of the major causes of dyspnea is Dynamic Hyperinflation (DH), which is caused by airflow limitation as well as increase in ventilation. The aims of our study were to compare DH at equal ventilation (isoventilation) during arm and legwork and to investigate the effects of breathing pattern on DH. METHODS: Thirteen clinically stable patients with mild to very severe COPD (forced expiratory volume in 1 s = 59% +/- 21%) participated in this study. Arm and leg constant work rate (CWR) ergometry were performed in random order with ventilation equal to that at 50% of peak armload. The corresponding leg load of that level of ventilation was determined from the incremental leg test. Respiratory physiology was measured breath-by-breath. Change in inspiratory capacity, measured at rest and at 2-min intervals, was used to reflect DH. RESULTS: At steady-state isoventilation (37 +/- 2 and 36 +/- 2 L . min for arm and leg CWR tests, respectively, P > 0.05), armload was 29 +/- 5 W and leg load was 52 +/- 6 W (P < 0.001). The level of DH, 0.32 +/- 0.09 and 0.27 +/- 0.08 L during arm and leg exercises, respectively, was not significantly different. However, breathing frequency was greater during arm than during leg exercise (24 +/- 1 vs 21 +/- 1 breaths per minute, P < 0.01), and the opposite was true for tidal volume (1.56 +/- 0.15 vs 1.69 +/- 0.14 L, P < 0.01). CONCLUSIONS: At similar ventilation, we found a similar degree of DH during arm and leg CWR tests in patients with mild to very severe COPD. Although differences in breathing pattern were observed between arm and leg exercises, these did not affect the level of DH.
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Dynamic Hyperinflation after metronome paced hyperventilation in copd a 2 year follow up
Respiratory Medicine, 2010Co-Authors: Jorien D. C. Hannink, Anke Lahaije, Hanneke Van Helvoort, Erik Bischoff, Richard Dekhuijzen, Tjard Schermer, Yvonne F HeijdraAbstract:Summary In contrast to the decline in FEV 1 , the behavior of Dynamic Hyperinflation (DH) over time is unknown in patients with COPD. Metronome-paced hyperventilation (MPH) is a simple applicable surrogate for exercise to detect DH. Objective To evaluate changes in MPH-induced DH during two years follow-up in mild-to-severe COPD patients. Additionally, influence of smoking status on DH and the relation between DH and other lung function parameters were assessed. Methods Patients were recruited from a randomized controlled trial conducted in general practice. Measurements of lung function and DH were performed at baseline and after 12 and 24 months. DH was assessed by MPH with breathing frequency set at twice the baseline rate. Change in inspiratory capacity after MPH was used to reflect change in end-expiratory lung volume and therefore DH, presuming constant total lung capacity. Results During follow-up, 68 patients completed all measurements. DH increased by 0.23 ± 0.06 L ( p ≤ 0.001). No significant changes in FEV 1 %pred were seen. Smokers had lower FEV 1 and a more rapid decline than non-smokers. DH in smokers increased more over time compared to non-smokers. The amount of DH correlated positively with resting inspiratory capacity. Conclusion After two years, a significant increase in MPH-induced DH in COPD patients was demonstrated, which was not accompanied by a decline in FEV 1 . It might be that DH is a sensitive measure to track consequences of changes in airflow obstruction.
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Dynamic Hyperinflation during daily activities does copd global initiative for chronic obstructive lung disease stage matter
Chest, 2010Co-Authors: Jorien D. C. Hannink, P. N. Richard Dekhuijzen, Hanneke Van Helvoort, Yvonne F HeijdraAbstract:Background One of the contributors to exercise limitation in COPD is Dynamic Hyperinflation. Although Dynamic Hyperinflation appears to occur during several exercise protocols in COPD and seems to increase with increasing disease severity, it is unknown whether Dynamic Hyperinflation occurs at different severity stages according to the Global initiative for chronic Obstructive Lung Disease (GOLD) in daily life. The present study, therefore, aimed to compare Dynamic Hyperinflation between COPD GOLD stages II-IV during daily activities. Methods Thirty-two clinically stable patients with COPD GOLD II (n = 10), III (n = 12), and IV (n = 10) participated in this study. Respiratory physiology during a daily activity was measured at patients' homes with Oxycon Mobile. Inspiratory capacity maneuvers were performed at rest, at 2-min intervals during the activity, and at the end of the activity. Change in inspiratory capacity is commonly used to reflect change in end-expiratory lung volume (ΔEELV) and, therefore, Dynamic Hyperinflation. The combination of static and Dynamic Hyperinflation was reflected by inspiratory reserve volume (IRV) during the activity. Results Overall, increase in EELV occurred in GOLD II-IV without significant difference between the groups. There was a tendency for a smaller ΔEELV in GOLD IV. ΔEELV was inversely related to static Hyperinflation. IRV during the daily activity was related to the level of airflow obstruction. Conclusions Dynamic Hyperinflation occurs independent of GOLD stage during real-life daily activities. The combination of static and Dynamic Hyperinflation, however, increases with increasing airflow obstruction.
Gerard J Criner - One of the best experts on this subject based on the ideXlab platform.
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G: Increased oxygen pulse after lung volume reduction surgery is associated with reduced Dynamic Hyperinflation
2020Co-Authors: Matthew R. Lammi, Nathaniel Marchetti, Gerard J Criner, David Ciccolella, Malcolm Kohler, Correspondence M R LammiAbstract:ABSTRACT: Stroke volume augmentation during exercise is limited in chronic obstructive pulmonary disease patients because of decreased preload from Dynamic Hyperinflation (DH). We hypothesised that oxygen pulse and pulse pressure (PP) improve following lung volume reduction surgery (LVRS), and the magnitude of improvement correlates with reduction in DH. We compared 16 emphysema patients undergoing LVRS with six emphysema patients not undergoing LVRS. Oxygen pulse and PP were calculated from maximal cardiopulmonary exercise tests at baseline and 6 months. End-expiratory lung volume (EELV)/total lung capacity (TLC) represented DH. Comparisons were made between baseline and 6 months at metabolic isotimes (per cent maximal carbon dioxide production (V9CO 2 ,max)). At baseline, the LVRS group was older with higher forced expiratory volume in 1 s, but had similar Hyperinflation to the non-LVRS group. At 6 months, oxygen pulse (50%, 75%, and 100% V9CO 2 ,max) and PP (50% and 75% V9CO 2 ,max) increased in the LVRS, but not in the non-LVRS group. Baseline functional residual capacity/TLC inversely correlated with resting oxygen pulse (r5 -0.449, p50.04). Decreased EELV/TLC correlated with increased oxygen pulse at 75% (r5 -0.487, p50.02) and 100% V9CO 2 ,max (r5 -0.548, p50.008). LVRS led to increased oxygen pulse and PP during exercise at metabolic isotimes 6 months following surgery. Reductions in DH correlated with increases in oxygen pulse during exercise. Reducing lung volume may improve stroke volume response to exercise by decreasing DH. KEYWORDS: Cardiopulmonary interactions, chronic obstructive pulmonary disease, exercise, physiology C hronic obstructive pulmonary disease (COPD) patients have impaired exercise tolerance, which limits their quality of life. While ventilatory limitations, including Dynamic Hyperinflation (DH), are the main cause of exercise intolerance in this population [1], causes for this impairment are probably multifactorial Along with its beneficial effects on mortality To investigate the effect of DH and LVRS on cardiac performance during exercise, we retrospectively analysed data from emphysema patients who had cardiopulmonary exercise tests (CPETs) before and after LVRS, and compared their changes with those who did not undergo LVRS. We hypothesised that LVRS would lead to an increase in non-invasive markers of stroke volume (oxygen puls
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Reduced Dynamic Hyperinflation after LVRS is associated with improved exercise tolerance.
Respiratory Medicine, 2014Co-Authors: Matthew R. Lammi, Nathaniel Marchetti, Gerard J CrinerAbstract:Summary Introduction Dynamic Hyperinflation (DH) after lung volume reduction surgery (LVRS) has not been well studied. It is not known if reductions in DH correlate with improvements in exercise performance post-LVRS. Methods Forty-two upper-lobe predominant emphysema patients who underwent LVRS were analyzed. Inspiratory capacity was measured every 2 min during symptom-limited cardiopulmonary exercise test (CPET) and end-expiratory lung volumes (EELV) were calculated. The main measure of DH was EELV/TLC ratio matched at metabolic isotimes (based on the post-rehabilitation VCO 2 max). Results Patients had very severe airflow obstruction (FEV1 28.3 ± 7.0% predicted), were hyperinflated (TLC 125 ± 17% predicted) and gas trapped (RV 198 ± 39% predicted). Compared to the post-rehab baseline, Dynamic Hyperinflation (EELV/TLC) was significantly reduced after LVRS at 6, 12, 24, and 36 months. There were also increases in inspiratory reserve volume at matched isotimes after surgery. Patients adopted a slower, deeper breathing pattern during exercise after LVRS, which strongly correlated to reductions in DH. There were significant correlations between reductions in DH (EELV/TLC @50% VCO 2 max) and improvements in 6 min walk distance (Pearson r = −0.411, p = 0.02, n = 33) and maximal watts on CPET (Spearman r = −0.536, p = 0.001, n = 33) when comparing post-rehabilitation and 6 month post-LVRS values. Conclusion Dynamic Hyperinflation during exercise was reduced after LVRS (up to 3 years) and there was a strong association between alterations in breathing pattern and reduced DH after LVRS. This is the first study to demonstrate that reductions in DH correlated with improved exercise performance following LVRS.
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Increased oxygen pulse after lung volume reduction surgery is associated with reduced Dynamic Hyperinflation
The European respiratory journal, 2012Co-Authors: Matthew R. Lammi, Nathaniel Marchetti, David Ciccolella, Malcolm Kohler, Gerard J CrinerAbstract:Stroke volume augmentation during exercise is limited in chronic obstructive pulmonary disease patients because of decreased preload from Dynamic Hyperinflation (DH). We hypothesised that oxygen pulse and pulse pressure (PP) improve following lung volume reduction surgery (LVRS), and the magnitude of improvement correlates with reduction in DH. We compared 16 emphysema patients undergoing LVRS with six emphysema patients not undergoing LVRS. Oxygen pulse and PP were calculated from maximal cardiopulmonary exercise tests at baseline and 6 months. End-expiratory lung volume (EELV)/total lung capacity (TLC) represented DH. Comparisons were made between baseline and 6 months at metabolic isotimes (per cent maximal carbon dioxide production (V9CO2,max)). At baseline, the LVRS group was older with higher forced expiratory volume in 1 s, but had similar Hyperinflation to the non-LVRS group. At 6 months, oxygen pulse (50%, 75%, and 100% V9CO2,max) and PP (50% and 75% V9CO2,max) increased in the LVRS, but not in the non-LVRS group. Baseline functional residual capacity/TLC inversely correlated with resting oxygen pulse (r5 -0.449, p50.04). Decreased EELV/TLC correlated with increased oxygen pulse at 75% (r5 -0.487, p50.02) and 100% V9CO2,max (r5 -0.548, p50.008). LVRS led to increased oxygen pulse and PP during exercise at metabolic isotimes 6 months following surgery. Reductions in DH correlated with increases in oxygen pulse during exercise. Reducing lung volume may improve stroke volume response to exercise by decreasing DH.
Michael I Polkey - One of the best experts on this subject based on the ideXlab platform.
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inspiratory capacity manoeuvres may underestimate Dynamic Hyperinflation in patients with copd the explanation for apparent non inflators
European Respiratory Journal, 2016Co-Authors: Yuanming Luo, Zhihui Qiu, Joerg Steier, Nanshan Zhong, John Moxham, Michael I PolkeyAbstract:Rationale Dynamic Hyperinflation in patients with COPD is usually assessed by inspiratory capacity (IC) manoeuvres with the assumption that maximal activation of the respiratory muscles can be reliably achieved. Objectives We hypothesized that the neural output to the respiratory muscles during an IC manoeuvre will increase under the condition of exercise or hypercapnia, since these are known to increase neural output from the brainstem to the respiratory muscles. Methods Nineteen patients with COPD (mean FEV 1 =29.7±12.5%) and 31 normal subjects were studied. Diaphragm electromyogram (EMGdi) and IC were measured during exhaustive exercise and during inhalation of 8%CO 2 with or without hypoxia. Measurements and Main Results IC changed from 1.78 ± 0.50 L and 1.41 ± 0.40 L at rest to 2.18 ± 0.58 L and 1.29 ± 0.46 L at the end of exercise for normal subjects and COPD patients, respectively. The mean EMGdi during an IC manoeuver increased during exercise from 0.158 ± 0.036 mV and 0.172 ± 0.048mV at rest to 0.203 ± 0.041 mV and 0.220 ± 0.056mV at the end of exercise for normal subjects and patients with COPD, respectively. Both the IC and EMGdi observed during an IC manoeuver during inhalation of 8%CO 2 in normal subjects was significantly larger than those breathing room air (2.10±0.80L vs 1.87±0.60L for IC and 0.183±0.038 mV vs 0.154±0.040 mV for EMGdi, p Conclusions We conclude that the neural drive generated by an IC manoeuvre increases during exercise and hypercapnia, leading to potential underestimation of Dynamic Hyperinflation assessed by IC manoeuvres.
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the impact of homogeneous versus heterogeneous emphysema on Dynamic Hyperinflation in patients with severe copd assessed for lung volume reduction
COPD: Journal of Chronic Obstructive Pulmonary Disease, 2015Co-Authors: Afroditi K Boutou, Michael I Polkey, Zaid Zoumot, Claire Davey, Arjun Nair, David M Hansell, Athanasios Z Jamurtas, Nicholas S HopkinsonAbstract:Dynamic Hyperinflation (DH) is a pathophysiologic hallmark of Chronic Obstructive Pulmonary Disease (COPD). The aim of this study was to investigate the impact of emphysema distribution on DH during a maximal cardiopulmonary exercise test (CPET) in patients with severe COPD. This was a retrospective analysis of prospectively collected data among severe COPD patients who underwent thoracic high-resolution computed tomography, full lung function measurements and maximal CPET with inspiratory manouvers as assessment for a lung volume reduction procedure. ΔIC was calculated by subtracting the end-exercise inspiratory capacity (eIC) from resting IC (rIC) and expressed as a percentage of rIC (ΔIC%). Emphysema quantification was conducted at 3 predefined levels using the syngo PULMO-CT (Siemens AG); a difference >25% between best and worse slice was defined as heterogeneous emphysema. Fifty patients with heterogeneous (62.7% male; 60.9 ± 7.5 years old; FEV1% = 32.4 ± 11.4) and 14 with homogeneous emphysema (61.5% male; 62.5 ± 5.9 years old; FEV1% = 28.1 ± 10.3) fulfilled the enrolment criteria. The groups were matched for all baseline variables. ΔIC% was significantly higher in homogeneous emphysema (39.8% ± 9.8% vs.31.2% ± 13%, p = 0.031), while no other CPET parameter differed between the groups. Upper lobe predominance of emphysema correlated positively with peak oxygen pulse, peak oxygen uptake and peak respiratory rate, and negatively with ΔIC%. Homogeneous emphysema is associated with more DH during maximum exercise in COPD patients.
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association between Dynamic Hyperinflation and emphysema distribution in copd patients
European Respiratory Journal, 2014Co-Authors: Afroditi K Boutou, Michael I Polkey, Zaid Zoumot, Claire Davey, Arjun Nair, David M Hansell, Nicholas S HopkinsonAbstract:Introduction Dynamic Hyperinflation (DH) is a major contributor of both dyspnea and reduced exercise capacity among patients with Chronic Obstructive Pulmonary Disease (COPD). The relationship between the pattern of distribution of emphysema (homogeneous versus heterogeneous) and DH has not been previously studied. Aim To compare the impact of emphysema distribution on DH during a maximal cardiopulmonary exercise testing (CPET) in severe COPD. Material-Methods Data on COPD patients who underwent thorax high-resolution computed tomography, full lung function measurements and maximal CPET were retrospectively analysed. Resting inspiratory capacity (rIC) was calculated by averaging 4 resting IC manouvers. ΔIC was calculated by subtracting the peak IC (pIC), that is the IC measured during the last 30 seconds of maximum exercise, from rIC and was expressed as ratio of rIC (ΔICratio). Emphysema quantification was conducted at 3 predefined levels for each patient using the syngo PULMO-CT (Siemens AG); a difference >25% between best and worse slice defined heterogeneous emphysema. Student9s t-test was used for group comparison, after normality of distribution was assessed; level of p Results We identified 51 patients with heterogeneous emphysema (62.7% male; 60.9±7.5 years old; FEV 1 %=32.4±11.4; TLCO%=34.1±10) and 13 with homogeneous emphysema (61.5% male; 62.5±5.9 years old; FEV 1 %=28.1±10.3; TLCO%=33.3±11.5) who fulfilled the enrollment criteria. ΔICratio (0.40±0.1 vs 0.31±0.13, p=0.031) was higher in patients with homogeneous compared to those with heterogeneous emphysema. Conclusion Homogeneous emphysema is associated with more DH during maximum exercise in COPD patients.
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effect of bronchoscopic lung volume reduction on Dynamic Hyperinflation and exercise in emphysema
American Journal of Respiratory and Critical Care Medicine, 2005Co-Authors: Nicholas S Hopkinson, John Moxham, David M Hansell, Tudor P Toma, Peter Goldstraw, Duncan M Geddes, Michael I PolkeyAbstract:Endobronchial valve placement improves pulmonary function in some patients with chronic obstructive pulmonary disease, but its effects on exercise physiology have not been investigated. In 19 patients with a mean (SD) FEV(1) of 28.4 (11.9)% predicted, studied before and 4 weeks after unilateral valve insertion, functional residual capacity decreased from 7.1 (1.5) to 6.6 (1.7) L (p = 0.03) and diffusing capacity rose from 3.3 (1.1) to 3.7 (1.2) mmol . minute(-1) . kPa(-1) (p = 0.03). Cycle endurance time at 80% of peak workload increased from 227 (129) to 315 (195) seconds (p = 0.03). This was associated with a reduction in end-expiratory lung volume at peak exercise from 7.6 (1.6) to 7.2 (1.7) L (p = 0.03). Using stepwise logistic regression analysis, a model containing changes in transfer factor and resting inspiratory capacity explained 81% of the variation in change in exercise time (p < 0.0001). The same variables were retained if the five patients with radiologic atelectasis were excluded from analysis. In a subgroup of patients in whom invasive measurements were performed, improvement in exercise capacity was associated with a reduction in lung compliance (r(2) = 0.43; p = 0.03) and isotime esophageal pressure-time product (r(2) = 0.47; p = 0.03). Endobronchial valve placement can improve lung volumes and gas transfer in patients with chronic obstructive pulmonary disease and prolong exercise time by reducing Dynamic Hyperinflation.
Matthew R. Lammi - One of the best experts on this subject based on the ideXlab platform.
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acute effect of inhaled iloprost on exercise Dynamic Hyperinflation in copd patients a randomized crossover study
Respiratory Medicine, 2021Co-Authors: Matthew R. Lammi, Mohamed A Ghonim, Jessica L Johnson, Johnny Daquin, John B Zamjahn, Andy Pellett, Samuel C Okpechi, Connie Romaine, Kusma Pyakurel, Hahn H LuuAbstract:Abstract Background and objective We tested whether the prostacyclin analog inhaled iloprost modulates dead space, Dynamic Hyperinflation (DH), and systemic inflammation/oxidative stress during maximal exercise in subjects with chronic obstructive pulmonary disease (COPD) who were not selected based on pulmonary hypertension (PH). Methods Twenty-four COPD patients with moderate-severe obstruction (age 59 ± 7 years, FEV1 53 ± 13% predicted) participated in a randomized, double-blind, placebo-controlled crossover trial. Each subject received a single nebulized dose of 5.0 μg iloprost or placebo on non-consecutive days followed by maximal cardiopulmonary exercise tests. The primary outcome was DH quantified by end-expiratory lung volume/total lung capacity ratio (EELV/TLC) at metabolic isotime. Results Inhaled iloprost was well-tolerated and reduced submaximal alveolar dead-space fraction but did not significantly reduce DH (0.70 ± 0.09 vs 0.69 ± 0.07 following placebo and iloprost, respectively, p = 0.38). Maximal exercise time (9.1 ± 2.3 vs 9.3 ± 2.2 min, p = 0.31) and peak oxygen uptake (17.4 ± 6.3 vs 17.9 ± 6.9 mL/kg/min, p = 0.30) were not significantly different following placebo versus iloprost. Conclusions A single dose of inhaled iloprost was safe and reduced alveolar dead space fraction; however, it was not efficacious in modulating DH or improving exercise capacity in COPD patients who were not selected for the presence of PH.
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G: Increased oxygen pulse after lung volume reduction surgery is associated with reduced Dynamic Hyperinflation
2020Co-Authors: Matthew R. Lammi, Nathaniel Marchetti, Gerard J Criner, David Ciccolella, Malcolm Kohler, Correspondence M R LammiAbstract:ABSTRACT: Stroke volume augmentation during exercise is limited in chronic obstructive pulmonary disease patients because of decreased preload from Dynamic Hyperinflation (DH). We hypothesised that oxygen pulse and pulse pressure (PP) improve following lung volume reduction surgery (LVRS), and the magnitude of improvement correlates with reduction in DH. We compared 16 emphysema patients undergoing LVRS with six emphysema patients not undergoing LVRS. Oxygen pulse and PP were calculated from maximal cardiopulmonary exercise tests at baseline and 6 months. End-expiratory lung volume (EELV)/total lung capacity (TLC) represented DH. Comparisons were made between baseline and 6 months at metabolic isotimes (per cent maximal carbon dioxide production (V9CO 2 ,max)). At baseline, the LVRS group was older with higher forced expiratory volume in 1 s, but had similar Hyperinflation to the non-LVRS group. At 6 months, oxygen pulse (50%, 75%, and 100% V9CO 2 ,max) and PP (50% and 75% V9CO 2 ,max) increased in the LVRS, but not in the non-LVRS group. Baseline functional residual capacity/TLC inversely correlated with resting oxygen pulse (r5 -0.449, p50.04). Decreased EELV/TLC correlated with increased oxygen pulse at 75% (r5 -0.487, p50.02) and 100% V9CO 2 ,max (r5 -0.548, p50.008). LVRS led to increased oxygen pulse and PP during exercise at metabolic isotimes 6 months following surgery. Reductions in DH correlated with increases in oxygen pulse during exercise. Reducing lung volume may improve stroke volume response to exercise by decreasing DH. KEYWORDS: Cardiopulmonary interactions, chronic obstructive pulmonary disease, exercise, physiology C hronic obstructive pulmonary disease (COPD) patients have impaired exercise tolerance, which limits their quality of life. While ventilatory limitations, including Dynamic Hyperinflation (DH), are the main cause of exercise intolerance in this population [1], causes for this impairment are probably multifactorial Along with its beneficial effects on mortality To investigate the effect of DH and LVRS on cardiac performance during exercise, we retrospectively analysed data from emphysema patients who had cardiopulmonary exercise tests (CPETs) before and after LVRS, and compared their changes with those who did not undergo LVRS. We hypothesised that LVRS would lead to an increase in non-invasive markers of stroke volume (oxygen puls
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Reduced Dynamic Hyperinflation after LVRS is associated with improved exercise tolerance.
Respiratory Medicine, 2014Co-Authors: Matthew R. Lammi, Nathaniel Marchetti, Gerard J CrinerAbstract:Summary Introduction Dynamic Hyperinflation (DH) after lung volume reduction surgery (LVRS) has not been well studied. It is not known if reductions in DH correlate with improvements in exercise performance post-LVRS. Methods Forty-two upper-lobe predominant emphysema patients who underwent LVRS were analyzed. Inspiratory capacity was measured every 2 min during symptom-limited cardiopulmonary exercise test (CPET) and end-expiratory lung volumes (EELV) were calculated. The main measure of DH was EELV/TLC ratio matched at metabolic isotimes (based on the post-rehabilitation VCO 2 max). Results Patients had very severe airflow obstruction (FEV1 28.3 ± 7.0% predicted), were hyperinflated (TLC 125 ± 17% predicted) and gas trapped (RV 198 ± 39% predicted). Compared to the post-rehab baseline, Dynamic Hyperinflation (EELV/TLC) was significantly reduced after LVRS at 6, 12, 24, and 36 months. There were also increases in inspiratory reserve volume at matched isotimes after surgery. Patients adopted a slower, deeper breathing pattern during exercise after LVRS, which strongly correlated to reductions in DH. There were significant correlations between reductions in DH (EELV/TLC @50% VCO 2 max) and improvements in 6 min walk distance (Pearson r = −0.411, p = 0.02, n = 33) and maximal watts on CPET (Spearman r = −0.536, p = 0.001, n = 33) when comparing post-rehabilitation and 6 month post-LVRS values. Conclusion Dynamic Hyperinflation during exercise was reduced after LVRS (up to 3 years) and there was a strong association between alterations in breathing pattern and reduced DH after LVRS. This is the first study to demonstrate that reductions in DH correlated with improved exercise performance following LVRS.
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Increased oxygen pulse after lung volume reduction surgery is associated with reduced Dynamic Hyperinflation
The European respiratory journal, 2012Co-Authors: Matthew R. Lammi, Nathaniel Marchetti, David Ciccolella, Malcolm Kohler, Gerard J CrinerAbstract:Stroke volume augmentation during exercise is limited in chronic obstructive pulmonary disease patients because of decreased preload from Dynamic Hyperinflation (DH). We hypothesised that oxygen pulse and pulse pressure (PP) improve following lung volume reduction surgery (LVRS), and the magnitude of improvement correlates with reduction in DH. We compared 16 emphysema patients undergoing LVRS with six emphysema patients not undergoing LVRS. Oxygen pulse and PP were calculated from maximal cardiopulmonary exercise tests at baseline and 6 months. End-expiratory lung volume (EELV)/total lung capacity (TLC) represented DH. Comparisons were made between baseline and 6 months at metabolic isotimes (per cent maximal carbon dioxide production (V9CO2,max)). At baseline, the LVRS group was older with higher forced expiratory volume in 1 s, but had similar Hyperinflation to the non-LVRS group. At 6 months, oxygen pulse (50%, 75%, and 100% V9CO2,max) and PP (50% and 75% V9CO2,max) increased in the LVRS, but not in the non-LVRS group. Baseline functional residual capacity/TLC inversely correlated with resting oxygen pulse (r5 -0.449, p50.04). Decreased EELV/TLC correlated with increased oxygen pulse at 75% (r5 -0.487, p50.02) and 100% V9CO2,max (r5 -0.548, p50.008). LVRS led to increased oxygen pulse and PP during exercise at metabolic isotimes 6 months following surgery. Reductions in DH correlated with increases in oxygen pulse during exercise. Reducing lung volume may improve stroke volume response to exercise by decreasing DH.
