Andrea Aliverti - Academia.edu (original) (raw)

Papers by Andrea Aliverti

Research paper thumbnail of Circulatory Effects of Expulsive Maneuvers

D24. CARDIO-PULMONARY INTERACTION IN ICU, 2009

Research paper thumbnail of Quantification Of Lung Function Using Proton Magnetic Resonance Imaging: Preliminary Findings In Lung Transplant Recipients

D13. SCIENTIFIC AND CLINICAL INNOVATIONS IN LUNG TRANSPLANTATION, 2012

Research paper thumbnail of Reply to Engel and Vemulpad

Journal of Applied Physiology, 2015

Research paper thumbnail of Effects of volume shift on the pressure-volume curve of the respiratory system in ALI/ARDS patients

Minerva anestesiologica, 2007

The pressure-volume (PV) curve in acute lung injury and acute respiratory distress syndrome (ALI/... more The pressure-volume (PV) curve in acute lung injury and acute respiratory distress syndrome (ALI/ARDS) patients has been proposed for estimating the underlying pathology, lung recruitment and setting mechanical ventilation. The supersyringe method may lead to artifacts due to thermodynamics and gas exchange. Another possible confounding factor is the volume shift, primarily blood, out of the chest wall when the intrathoracic pressures rise. We set out to quantify the volume shift and investigate its mechanisms. Ten ALI/ARDS patients (5 males/5 females, PaO(2)/FiO(2) 222+/-67) were studied in the Intensive Care Unit, University Hospital. PV curve was performed by a supersyringe (0.100 L, 14 steps Delta-Vgas) while recording the chest wall volume difference (Delta-Vcw) by the optoelectronic plethysmography. Differences in airway (Delta-Paw) and esophageal (Delta-Pes) pressures were measured during the maneuver. Volume shift was defined as Delta-Vcw-Delta-Vgas, corrected for thermodyna...

Research paper thumbnail of Correlated variability in the breathing pattern and end-expiratory lung volumes in conscious humans

PloS one, 2015

In order to characterize the variability and correlation properties of spontaneous breathing in h... more In order to characterize the variability and correlation properties of spontaneous breathing in humans, the breathing pattern of 16 seated healthy subjects was studied during 40 min of quiet breathing using opto-electronic plethysmography, a contactless technology that measures total and compartmental chest wall volumes without interfering with the subjects breathing. From these signals, tidal volume (VT), respiratory time (TTOT) and the other breathing pattern parameters were computed breath-by-breath together with the end-expiratory total and compartmental (pulmonary rib cage and abdomen) chest wall volume changes. The correlation properties of these variables were quantified by detrended fluctuation analysis, computing the scaling exponentα. VT, TTOT and the other breathing pattern variables showed α values between 0.60 (for minute ventilation) to 0.71 (for respiratory rate), all significantly lower than the ones obtained for end-expiratory volumes, that ranged between 1.05 (for ...

Research paper thumbnail of Low abdominal contribution to breathing as daytime predictor of nocturnal desaturation in adolescents and young adults with Duchenne Muscular Dystrophy

Respiratory medicine, 2012

In the respiratory management of DMD patients it is still under debate what parameter should indi... more In the respiratory management of DMD patients it is still under debate what parameter should indicate the correct timing for institution of nocturnal non-invasive ventilation (NIV), in addition to forced vital capacity, which is generally considered as a prognostic marker of disease progression. The aim of this study was to determine if volume variations of rib cage and abdominal compartments measured by Opto-Electronic Plethysmography can be helpful to distinguish between those patients who are in the early stages of nocturnal oxygen desaturation development and those who do not yet. Pulmonary function, abdominal contribution to tidal volume and to inspiratory capacity (%Abd IC) and a set of breathing pattern indexes were assessed in 40 DMD patients older than 14 years and not yet under nocturnal NIV. ROC analysis revealed that among all the considered parameters, %Abd IC in supine position was the best discriminator between DeSat (at least 10% of the night time with SpO(2) < 95...

Research paper thumbnail of Chest wall mechanics during pressure support ventilation

Critical care (London, England), 2006

During pressure support ventilation (PSV) a part of the breathing pattern is controlled by the pa... more During pressure support ventilation (PSV) a part of the breathing pattern is controlled by the patient, and synchronization of respiratory muscle action and the resulting chest wall kinematics is a valid indicator of the patient's adaptation to the ventilator. The aim of the present study was to analyze the effects of different PSV settings on ventilatory pattern, total and compartmental chest wall kinematics and dynamics, muscle pressures and work of breathing in patients with acute lung injury. In nine patients four different levels of PSV (5, 10, 15 and 25 cmH2O) were randomly applied with the same level of positive end-expiratory pressure (10 cmH2O). Flow, airway opening, and oesophageal and gastric pressures were measured, and volume variations for the entire chest wall, the ribcage and abdominal compartments were recorded by opto-electronic plethysmography. The pressure and the work generated by the diaphragm, rib cage and abdominal muscles were determined using dynamic pr...

Research paper thumbnail of Detection of expiratory flow limitation in COPD using the forced oscillation technique

The European respiratory journal, 2004

Expiratory flow limitation (EFL) during tidal breathing is a major determinant of dynamic hyperin... more Expiratory flow limitation (EFL) during tidal breathing is a major determinant of dynamic hyperinflation and exercise limitation in chronic obstructive pulmonary disease (COPD). Current methods of detecting this are either invasive or unsuited to following changes breath-by-breath. It was hypothesised that tidal flow limitation would substantially reduce the total respiratory system reactance (Xrs) during expiration, and that this reduction could be used to reliably detect if EFL was present. To test this, 5-Hz forced oscillations were applied at the mouth in seven healthy subjects and 15 COPD patients (mean +/- sD forced expiratory volume in one second was 36.8 +/- 11.5% predicted) during quiet breathing. COPD breaths were analysed (n=206) and classified as flow-limited if flow decreased as alveolar pressure increased, indeterminate if flow decreased at constant alveolar pressure, or nonflow-limited. Of these, 85 breaths were flow-limited, 80 were not and 41 were indeterminate. Amo...

Research paper thumbnail of Chest wall kinematic determinants of diaphragm length by optoelectronic plethysmography and ultrasonography

Journal of applied physiology (Bethesda, Md. : 1985), 2003

To estimate diaphragm fiber length from thoracoabdominal configuration, we measured axial motion ... more To estimate diaphragm fiber length from thoracoabdominal configuration, we measured axial motion of the right-sided area of apposition by ultrasonography and volumes displaced by chest wall compartments [pulmonary, abdominal rib cage, and abdomen (Vab)] by optoelectronic plethysmography in four normal men during quiet breathing and incremental exercise without and with expiratory flow limitation. Points at the cephalic area of apposition border were digitized from echo images and mapped into three-dimensional space, and the axial distance from the xyphoidal transverse plane (D(ap)) was measured simultaneously with the volumes. Linear regression analysis between changes (Delta) in D(ap) and the measured volume changes under all conditions showed that 1) DeltaD(ap) was linearly related more to DeltaVab than to changes in pulmonary and abdominal rib cage volumes; and 2) this was highly repeatable between measures. Multiple stepwise regression analysis showed that DeltaVab accounted for...

Research paper thumbnail of Human respiratory muscle actions and control during exercise

Journal of applied physiology (Bethesda, Md. : 1985), 1997

We measured pressures and power of diaphragm, rib cage, and abdominal muscles during quiet breath... more We measured pressures and power of diaphragm, rib cage, and abdominal muscles during quiet breathing (QB) and exercise at 0, 30, 50, and 70% maximum workload (Wmax) in five men. By three-dimensional tracking of 86 chest wall markers, we calculated the volumes of lung- and diaphragm-apposed rib cage compartments (Vrc,p and Vrc,a, respectively) and the abdomen (Vab). End-inspiratory lung volume increased with percentage of Wmax as a result of an increase in Vrc,p and Vrc,a. End-expiratory lung volume decreased as a result of a decrease in Vab. DeltaVrc,a/DeltaVab was constant and independent of Wmax. Thus we used DeltaVab/time as an index of diaphragm velocity of shortening. From QB to 70% Wmax, diaphragmatic pressure (Pdi) increased approximately 2-fold, diaphragm velocity of shortening 6.5-fold, and diaphragm workload 13-fold. Abdominal muscle pressure was approximately 0 during QB but was equal to and 180 degrees out of phase with rib cage muscle pressure at all percent Wmax. Rib c...

Research paper thumbnail of Rib cage mechanics during quiet breathing and exercise in humans

Journal of applied physiology (Bethesda, Md. : 1985), 1997

During exercise, large pleural, abdominal, and transdiaphragmatic pressure swings might produce s... more During exercise, large pleural, abdominal, and transdiaphragmatic pressure swings might produce substantial rib cage (RC) distortions. We used a three-compartment chest wall model (J. Appl. Physiol. 72: 1338-1347, 1992) to measure distortions of lung- and diaphragm-apposed RC compartments (RCp and RCa) along with pleural and abdominal pressures in five normal men. RCp and RCa volumes were calculated from three-dimensional locations of 86 markers on the chest wall, and the undistorted (relaxation) RC configuration was measured. Compliances of RCp and RCa measured during phrenic stimulation against a closed airway were 20 and 0%, respectively, of their values during relaxation. There was marked RC distortion. Thus nonuniform distribution of pressures distorts the RC and markedly stiffens it. However, during steady-state ergometer exercise at 0, 30, 50, and 70% of maximum workload, RC distortions were small because of a coordinated action of respiratory muscles, so that net pressures a...

Research paper thumbnail of Chest wall and lung volume estimation by optical reflectance motion analysis

Journal of applied physiology (Bethesda, Md. : 1985), 1996

Estimation of chest wall motion by surface measurements only allows one-dimensional measurements ... more Estimation of chest wall motion by surface measurements only allows one-dimensional measurements of the chest wall. We have assessed on optical reflectance system (OR), which tracks reflective markers in three dimensions (3-D) for respiratory use. We used 86 (6-mm-diameter) hemispherical reflective markers arranged circumferentially on the chest wall in seven rows between the sternal notch and the anterior superior iliac crest in two normal standing subjects. We calculated the volume of the entire chest wall and compared inspired and expired volumes with volumes obtained by spirometry. Marker positions were recorded by four TV cameras; two were 4 m in front of and two were 4 m behind the subject. The TV signals were sampled at 100 Hz and combined with grid calibration parameters on a personal computer to obtain the 3-D coordinates of the markers. Chest wall surfaces were reconstructed by triangulation through the point data, and chest wall volume was calculated. During tidal breathi...

Research paper thumbnail of Muscle Impairment in Neuromuscular Disease Using an Expiratory/Inspiratory Ratio

Respiratory care, Jan 13, 2015

Neuromuscular diseases (NMDs) lead to different weakness patterns, and most patients with NMDs de... more Neuromuscular diseases (NMDs) lead to different weakness patterns, and most patients with NMDs develop respiratory failure. Inspiratory and expiratory muscle strength can be measured by maximum static inspiratory pressure (PImax) and maximum static expiratory pressure (PEmax), and the relationship between them has not been well described in healthy subjects and subjects with NMDs. Our aim was to assess expiratory/inspiratory muscle strength in NMDs and healthy subjects and calculate PEmax/PImax ratio for these groups. Seventy (35 males) subjects with NMDs (amyotrophic lateral sclerosis, myasthenia gravis, and myotonic dystrophy), and 93 (47 males) healthy individuals 20 - 80 y of age were evaluated for anthropometry, pulmonary function, PImax, and PEmax, respectively. Healthy individuals showed greater values for PImax and PEmax when compared with subjects with NMDs. PEmax/PImax ratio for healthy subjects was 1.31 ± 0.26, and PEmax%/PImax% was 1.04 ± 0.05; for subjects with NMDs, PE...

Research paper thumbnail of Effects of rapid saline infusion on lung mechanics and airway responsiveness in humans

Journal of applied physiology (Bethesda, Md. : 1985), 2003

Lung mechanics and airway responsiveness to methacholine (MCh) were studied in seven volunteers b... more Lung mechanics and airway responsiveness to methacholine (MCh) were studied in seven volunteers before and after a 20-min intravenous infusion of saline. Data were compared with those of a time point-matched control study. The following parameters were measured: 1-s forced expiratory volume, forced vital capacity, flows at 40% of control forced vital capacity on maximal (Vm(40)) and partial (Vp(40)) forced expiratory maneuvers, lung volumes, lung elastic recoil, lung resistance (Rl), dynamic elastance (Edyn), and within-breath resistance of respiratory system (Rrs). Rl and Edyn were measured during tidal breathing before and for 2 min after a deep inhalation and also at different lung volumes above and below functional residual capacity. Rrs was measured at functional residual capacity and at total lung capacity. Before MCh, saline infusion caused significant decrements of forced expiratory volume in 1 s, Vm(40), and Vp(40), but insignificantly affected lung volumes, elastic recoil,...

Research paper thumbnail of PloS one Volume: 4 ISSN: 1932-6203 ISO Abbreviation: PLoS ONE Publication Date: 2009

... Daniela Brunert 1 3, Stefan Kurtenbach 1, Sonnur Isik 2, Heike Benecke 1, ... [pmid: 7514300]... more ... Daniela Brunert 1 3, Stefan Kurtenbach 1, Sonnur Isik 2, Heike Benecke 1, ... [pmid: 7514300]. 18. Monti-Graziadei G,Margolis F,Harding J,Graziadei P. 1977;Immunocytochemistry of the olfactory marker protein.J Histochem Cytochem 25:1311–1316. [pmid: 336785]. 19. ...

Research paper thumbnail of Analysis of Regional Lung Ventilation

Research paper thumbnail of Transfer function (Z (TR)) of the respiratory system by forced oscillation technique (FOT) and optimetrics

Research paper thumbnail of Breathing patterns in asthmatics measured non invasively by optimetrics

Research paper thumbnail of Effect of different tidal volumes and PEEP levels on gas exchange and FRC

Research paper thumbnail of Functional electrical stimulation of abdominal muscles (FESAM) in spinal cord injury during phrenic nerve stimulation

Research paper thumbnail of Circulatory Effects of Expulsive Maneuvers

D24. CARDIO-PULMONARY INTERACTION IN ICU, 2009

Research paper thumbnail of Quantification Of Lung Function Using Proton Magnetic Resonance Imaging: Preliminary Findings In Lung Transplant Recipients

D13. SCIENTIFIC AND CLINICAL INNOVATIONS IN LUNG TRANSPLANTATION, 2012

Research paper thumbnail of Reply to Engel and Vemulpad

Journal of Applied Physiology, 2015

Research paper thumbnail of Effects of volume shift on the pressure-volume curve of the respiratory system in ALI/ARDS patients

Minerva anestesiologica, 2007

The pressure-volume (PV) curve in acute lung injury and acute respiratory distress syndrome (ALI/... more The pressure-volume (PV) curve in acute lung injury and acute respiratory distress syndrome (ALI/ARDS) patients has been proposed for estimating the underlying pathology, lung recruitment and setting mechanical ventilation. The supersyringe method may lead to artifacts due to thermodynamics and gas exchange. Another possible confounding factor is the volume shift, primarily blood, out of the chest wall when the intrathoracic pressures rise. We set out to quantify the volume shift and investigate its mechanisms. Ten ALI/ARDS patients (5 males/5 females, PaO(2)/FiO(2) 222+/-67) were studied in the Intensive Care Unit, University Hospital. PV curve was performed by a supersyringe (0.100 L, 14 steps Delta-Vgas) while recording the chest wall volume difference (Delta-Vcw) by the optoelectronic plethysmography. Differences in airway (Delta-Paw) and esophageal (Delta-Pes) pressures were measured during the maneuver. Volume shift was defined as Delta-Vcw-Delta-Vgas, corrected for thermodyna...

Research paper thumbnail of Correlated variability in the breathing pattern and end-expiratory lung volumes in conscious humans

PloS one, 2015

In order to characterize the variability and correlation properties of spontaneous breathing in h... more In order to characterize the variability and correlation properties of spontaneous breathing in humans, the breathing pattern of 16 seated healthy subjects was studied during 40 min of quiet breathing using opto-electronic plethysmography, a contactless technology that measures total and compartmental chest wall volumes without interfering with the subjects breathing. From these signals, tidal volume (VT), respiratory time (TTOT) and the other breathing pattern parameters were computed breath-by-breath together with the end-expiratory total and compartmental (pulmonary rib cage and abdomen) chest wall volume changes. The correlation properties of these variables were quantified by detrended fluctuation analysis, computing the scaling exponentα. VT, TTOT and the other breathing pattern variables showed α values between 0.60 (for minute ventilation) to 0.71 (for respiratory rate), all significantly lower than the ones obtained for end-expiratory volumes, that ranged between 1.05 (for ...

Research paper thumbnail of Low abdominal contribution to breathing as daytime predictor of nocturnal desaturation in adolescents and young adults with Duchenne Muscular Dystrophy

Respiratory medicine, 2012

In the respiratory management of DMD patients it is still under debate what parameter should indi... more In the respiratory management of DMD patients it is still under debate what parameter should indicate the correct timing for institution of nocturnal non-invasive ventilation (NIV), in addition to forced vital capacity, which is generally considered as a prognostic marker of disease progression. The aim of this study was to determine if volume variations of rib cage and abdominal compartments measured by Opto-Electronic Plethysmography can be helpful to distinguish between those patients who are in the early stages of nocturnal oxygen desaturation development and those who do not yet. Pulmonary function, abdominal contribution to tidal volume and to inspiratory capacity (%Abd IC) and a set of breathing pattern indexes were assessed in 40 DMD patients older than 14 years and not yet under nocturnal NIV. ROC analysis revealed that among all the considered parameters, %Abd IC in supine position was the best discriminator between DeSat (at least 10% of the night time with SpO(2) < 95...

Research paper thumbnail of Chest wall mechanics during pressure support ventilation

Critical care (London, England), 2006

During pressure support ventilation (PSV) a part of the breathing pattern is controlled by the pa... more During pressure support ventilation (PSV) a part of the breathing pattern is controlled by the patient, and synchronization of respiratory muscle action and the resulting chest wall kinematics is a valid indicator of the patient's adaptation to the ventilator. The aim of the present study was to analyze the effects of different PSV settings on ventilatory pattern, total and compartmental chest wall kinematics and dynamics, muscle pressures and work of breathing in patients with acute lung injury. In nine patients four different levels of PSV (5, 10, 15 and 25 cmH2O) were randomly applied with the same level of positive end-expiratory pressure (10 cmH2O). Flow, airway opening, and oesophageal and gastric pressures were measured, and volume variations for the entire chest wall, the ribcage and abdominal compartments were recorded by opto-electronic plethysmography. The pressure and the work generated by the diaphragm, rib cage and abdominal muscles were determined using dynamic pr...

Research paper thumbnail of Detection of expiratory flow limitation in COPD using the forced oscillation technique

The European respiratory journal, 2004

Expiratory flow limitation (EFL) during tidal breathing is a major determinant of dynamic hyperin... more Expiratory flow limitation (EFL) during tidal breathing is a major determinant of dynamic hyperinflation and exercise limitation in chronic obstructive pulmonary disease (COPD). Current methods of detecting this are either invasive or unsuited to following changes breath-by-breath. It was hypothesised that tidal flow limitation would substantially reduce the total respiratory system reactance (Xrs) during expiration, and that this reduction could be used to reliably detect if EFL was present. To test this, 5-Hz forced oscillations were applied at the mouth in seven healthy subjects and 15 COPD patients (mean +/- sD forced expiratory volume in one second was 36.8 +/- 11.5% predicted) during quiet breathing. COPD breaths were analysed (n=206) and classified as flow-limited if flow decreased as alveolar pressure increased, indeterminate if flow decreased at constant alveolar pressure, or nonflow-limited. Of these, 85 breaths were flow-limited, 80 were not and 41 were indeterminate. Amo...

Research paper thumbnail of Chest wall kinematic determinants of diaphragm length by optoelectronic plethysmography and ultrasonography

Journal of applied physiology (Bethesda, Md. : 1985), 2003

To estimate diaphragm fiber length from thoracoabdominal configuration, we measured axial motion ... more To estimate diaphragm fiber length from thoracoabdominal configuration, we measured axial motion of the right-sided area of apposition by ultrasonography and volumes displaced by chest wall compartments [pulmonary, abdominal rib cage, and abdomen (Vab)] by optoelectronic plethysmography in four normal men during quiet breathing and incremental exercise without and with expiratory flow limitation. Points at the cephalic area of apposition border were digitized from echo images and mapped into three-dimensional space, and the axial distance from the xyphoidal transverse plane (D(ap)) was measured simultaneously with the volumes. Linear regression analysis between changes (Delta) in D(ap) and the measured volume changes under all conditions showed that 1) DeltaD(ap) was linearly related more to DeltaVab than to changes in pulmonary and abdominal rib cage volumes; and 2) this was highly repeatable between measures. Multiple stepwise regression analysis showed that DeltaVab accounted for...

Research paper thumbnail of Human respiratory muscle actions and control during exercise

Journal of applied physiology (Bethesda, Md. : 1985), 1997

We measured pressures and power of diaphragm, rib cage, and abdominal muscles during quiet breath... more We measured pressures and power of diaphragm, rib cage, and abdominal muscles during quiet breathing (QB) and exercise at 0, 30, 50, and 70% maximum workload (Wmax) in five men. By three-dimensional tracking of 86 chest wall markers, we calculated the volumes of lung- and diaphragm-apposed rib cage compartments (Vrc,p and Vrc,a, respectively) and the abdomen (Vab). End-inspiratory lung volume increased with percentage of Wmax as a result of an increase in Vrc,p and Vrc,a. End-expiratory lung volume decreased as a result of a decrease in Vab. DeltaVrc,a/DeltaVab was constant and independent of Wmax. Thus we used DeltaVab/time as an index of diaphragm velocity of shortening. From QB to 70% Wmax, diaphragmatic pressure (Pdi) increased approximately 2-fold, diaphragm velocity of shortening 6.5-fold, and diaphragm workload 13-fold. Abdominal muscle pressure was approximately 0 during QB but was equal to and 180 degrees out of phase with rib cage muscle pressure at all percent Wmax. Rib c...

Research paper thumbnail of Rib cage mechanics during quiet breathing and exercise in humans

Journal of applied physiology (Bethesda, Md. : 1985), 1997

During exercise, large pleural, abdominal, and transdiaphragmatic pressure swings might produce s... more During exercise, large pleural, abdominal, and transdiaphragmatic pressure swings might produce substantial rib cage (RC) distortions. We used a three-compartment chest wall model (J. Appl. Physiol. 72: 1338-1347, 1992) to measure distortions of lung- and diaphragm-apposed RC compartments (RCp and RCa) along with pleural and abdominal pressures in five normal men. RCp and RCa volumes were calculated from three-dimensional locations of 86 markers on the chest wall, and the undistorted (relaxation) RC configuration was measured. Compliances of RCp and RCa measured during phrenic stimulation against a closed airway were 20 and 0%, respectively, of their values during relaxation. There was marked RC distortion. Thus nonuniform distribution of pressures distorts the RC and markedly stiffens it. However, during steady-state ergometer exercise at 0, 30, 50, and 70% of maximum workload, RC distortions were small because of a coordinated action of respiratory muscles, so that net pressures a...

Research paper thumbnail of Chest wall and lung volume estimation by optical reflectance motion analysis

Journal of applied physiology (Bethesda, Md. : 1985), 1996

Estimation of chest wall motion by surface measurements only allows one-dimensional measurements ... more Estimation of chest wall motion by surface measurements only allows one-dimensional measurements of the chest wall. We have assessed on optical reflectance system (OR), which tracks reflective markers in three dimensions (3-D) for respiratory use. We used 86 (6-mm-diameter) hemispherical reflective markers arranged circumferentially on the chest wall in seven rows between the sternal notch and the anterior superior iliac crest in two normal standing subjects. We calculated the volume of the entire chest wall and compared inspired and expired volumes with volumes obtained by spirometry. Marker positions were recorded by four TV cameras; two were 4 m in front of and two were 4 m behind the subject. The TV signals were sampled at 100 Hz and combined with grid calibration parameters on a personal computer to obtain the 3-D coordinates of the markers. Chest wall surfaces were reconstructed by triangulation through the point data, and chest wall volume was calculated. During tidal breathi...

Research paper thumbnail of Muscle Impairment in Neuromuscular Disease Using an Expiratory/Inspiratory Ratio

Respiratory care, Jan 13, 2015

Neuromuscular diseases (NMDs) lead to different weakness patterns, and most patients with NMDs de... more Neuromuscular diseases (NMDs) lead to different weakness patterns, and most patients with NMDs develop respiratory failure. Inspiratory and expiratory muscle strength can be measured by maximum static inspiratory pressure (PImax) and maximum static expiratory pressure (PEmax), and the relationship between them has not been well described in healthy subjects and subjects with NMDs. Our aim was to assess expiratory/inspiratory muscle strength in NMDs and healthy subjects and calculate PEmax/PImax ratio for these groups. Seventy (35 males) subjects with NMDs (amyotrophic lateral sclerosis, myasthenia gravis, and myotonic dystrophy), and 93 (47 males) healthy individuals 20 - 80 y of age were evaluated for anthropometry, pulmonary function, PImax, and PEmax, respectively. Healthy individuals showed greater values for PImax and PEmax when compared with subjects with NMDs. PEmax/PImax ratio for healthy subjects was 1.31 ± 0.26, and PEmax%/PImax% was 1.04 ± 0.05; for subjects with NMDs, PE...

Research paper thumbnail of Effects of rapid saline infusion on lung mechanics and airway responsiveness in humans

Journal of applied physiology (Bethesda, Md. : 1985), 2003

Lung mechanics and airway responsiveness to methacholine (MCh) were studied in seven volunteers b... more Lung mechanics and airway responsiveness to methacholine (MCh) were studied in seven volunteers before and after a 20-min intravenous infusion of saline. Data were compared with those of a time point-matched control study. The following parameters were measured: 1-s forced expiratory volume, forced vital capacity, flows at 40% of control forced vital capacity on maximal (Vm(40)) and partial (Vp(40)) forced expiratory maneuvers, lung volumes, lung elastic recoil, lung resistance (Rl), dynamic elastance (Edyn), and within-breath resistance of respiratory system (Rrs). Rl and Edyn were measured during tidal breathing before and for 2 min after a deep inhalation and also at different lung volumes above and below functional residual capacity. Rrs was measured at functional residual capacity and at total lung capacity. Before MCh, saline infusion caused significant decrements of forced expiratory volume in 1 s, Vm(40), and Vp(40), but insignificantly affected lung volumes, elastic recoil,...

Research paper thumbnail of PloS one Volume: 4 ISSN: 1932-6203 ISO Abbreviation: PLoS ONE Publication Date: 2009

... Daniela Brunert 1 3, Stefan Kurtenbach 1, Sonnur Isik 2, Heike Benecke 1, ... [pmid: 7514300]... more ... Daniela Brunert 1 3, Stefan Kurtenbach 1, Sonnur Isik 2, Heike Benecke 1, ... [pmid: 7514300]. 18. Monti-Graziadei G,Margolis F,Harding J,Graziadei P. 1977;Immunocytochemistry of the olfactory marker protein.J Histochem Cytochem 25:1311–1316. [pmid: 336785]. 19. ...

Research paper thumbnail of Analysis of Regional Lung Ventilation

Research paper thumbnail of Transfer function (Z (TR)) of the respiratory system by forced oscillation technique (FOT) and optimetrics

Research paper thumbnail of Breathing patterns in asthmatics measured non invasively by optimetrics

Research paper thumbnail of Effect of different tidal volumes and PEEP levels on gas exchange and FRC

Research paper thumbnail of Functional electrical stimulation of abdominal muscles (FESAM) in spinal cord injury during phrenic nerve stimulation