The use of a mixture of helium with oxygen (heliox) as a breathing gas may be beneficial due to its unique physical properties, such as low density and high carbon dioxide (CO2) diffusion coefficient. In previous studies in neonates with respiratory failure, conventional ventilation with heliox was associated with improved oxygenation and selected respiratory parameters. The use of heliox may increase the effectiveness of intermittent nasal positive pressure ventilation (NIPPV), but knowledge about the effects of such therapy on newborns is limited.The use of non- invasive neurally adjusted ventilatory assist (NIV-NAVA) allows synchronization and assessment of electrical activity of the diaphragm (EaDI) during heliox administration in premature babies with respiratory failure.
Aim of the study was to assess of the impact of non-invasive ventilation with heliox on respiratory function, diaphragm bioelectrical activity, cerebral oxygenation and selected vital signs in premature neonates with respiratory failure. 23 neonates ≤32 weeks gestational age (GA) were enrolled in the study. Patients were eligible for inclusion when ventilated due to respiratory failure, and in group 1 (n=12) on NIV as primary modality with oxygen requirement of 0.25-0.4 in the first 72 hours of life, or in group 2 (n=11) ready to extubate according to the given criteria. Newborns were ventilated with NIV NAVA and standard breathing gas (air-oxygen) at baseline. Heliox was introduced for 3 hours, followed by 3 hours of air-oxygen. NAVA level was kept constant and pulse oximeter oxygen saturation (SpO2) kept in range of 90-95%. Recorded parameters included heart rate (HR), SpO2 and cerebral tissue oxygenation (StO2). Selected ventilation parameters: peak inspiratory pressure (PIP), positive end-expiratory pressure (PEEP), mean airway pressure (MAP), air leakage during NIV, fraction of inspired oxygen (FiO2) as well as electrical activity of the diaphragm (EaDI mean, minimum and maximum) were also acquired. Blood gas analysis was performed in each period of the study. Statistical analysis was completed with ANOVA Friedman's test and single-factor repeated-measures analysis of variance.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
23
NIV-NAVA with a conventional gas mixture (air-oxygen) at baseline, 3 hours of NIV-NAVA with heliox and return to NIV-NAVA with air-oxygen.
Gynecological and obstetric teaching hospital, Departament of Neonatology, Polna street 33
Poznan, Great Poland, Poland
baseline minimal electric activity of the diaphragm (EaDI min)
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV, microvolts\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured at baseline
baseline mean electric activity of the diaphragm (EaDI mean)
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured at baseline
baseline maximal electric activity of the diaphragm (EaDI max)
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured at baseline
minimal electric activity of the diaphragm (EaDI min) after 15 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 15 minutes of heliox ventilation
mean electric activity of the diaphragm (EaDI mean) after 15 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 15 minutes of heliox ventilation
maximal electric activity of the diaphragm (EaDI max) after 15 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 15 minutes of heliox ventilation
minimal electric activity of the diaphragm (EaDI min) after 60 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 60 minutes of heliox ventilation
mean electric activity of the diaphragm (EaDI mean) after 60 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 60 minutes of heliox ventilation
maximal electric activity of the diaphragm (EaDI max) after 60 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 60 minutes of heliox ventilation
minimal electric activity of the diaphragm (EaDI min) after 180 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 180 minutes of heliox ventilation
mean electric activity of the diaphragm (EaDI mean) after 180 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 180 minutes of heliox ventilation
maximal electric activity of the diaphragm (EaDI max) after 180 minutes of heliox
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 180 minutes of heliox ventilation
minimal electric activity of the diaphragm (EaDI min) after 15 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 15 minutes since the return to ventilation with standard mixture
mean electric activity of the diaphragm (EaDI mean) after 15 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 15 minutes since the return to ventilation with standard mixture
maximal electric activity of the diaphragm (EaDI max) after 15 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 15 minutes since the return to ventilation with standard mixture
minimal electric activity of the diaphragm (EaDI min) after 60 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
mean electric activity of the diaphragm (EaDI mean) after 60 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
maximal electric activity of the diaphragm (EaDI max) after 60 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
minimal electric activity of the diaphragm (EaDI min) after 180 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI min \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
mean electric activity of the diaphragm (EaDI mean) after 180 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI mean \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
maximal electric activity of the diaphragm (EaDI max) after 180 minutes of standard mixture
Using the NAVA (neurally adjusted ventilatory assist) module of the Maquet Servo-i ventilator and "Servo-tracker" software EaDI max \[mcV\] values will be recorded during the study and their values will be compared between the heliox and air-oxygen NIV (non -invasive ventilation).
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
baseline PIP (peak inspiratory pressure)
PIP \[cm H2O, centimeters of water\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
baseline PEEP (positive end-expiratory pressure)
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
baseline MAP (mean airway pressure)
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
PIP (peak inspiratory pressure) after 15 minutes of heliox
PIP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes of heliox ventilation
PIP (peak inspiratory pressure) after 60 minutes of heliox
PIP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes of heliox ventilation
PIP (peak inspiratory pressure) after 180 minutes of heliox
PIP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes of heliox ventilation
PIP (peak inspiratory pressure) after 15 minutes of standard mixture
PIP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes since the return to ventilation with standard mixture
PIP (peak inspiratory pressure) after 60 minutes of standard mixture
PIP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
PIP (peak inspiratory pressure) after 180 minutes of standard mixture
PIP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
PEEP (positive end-expiratory pressure) after 15 minutes of heliox
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes of heliox ventilation
PEEP (positive end-expiratory pressure) after 60 minutes of heliox
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes of heliox ventilation
PEEP (positive end-expiratory pressure) after 180 minutes of heliox
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes of heliox ventilation
PEEP (positive end-expiratory pressure) after 15 minutes of standard mixture
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes since the return to ventilation with standard mixture
PEEP (positive end-expiratory pressure) after 60 minutes of standard mixture
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
PEEP (positive end-expiratory pressure) after 180 minutes of standard mixture
PEEP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
MAP (mean airway pressure) after 15 minutes of heliox
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes of heliox ventilation
MAP (mean airway pressure) after 60 minutes of heliox
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes of heliox ventilation
MAP (mean airway pressure) after 180 minutes of heliox
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes of heliox ventilation
MAP (mean airway pressure) after 15 minutes of standard ventilation
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
MAP (mean airway pressure) after 60 minutes of standard ventilation
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
MAP (mean airway pressure) after 180 minutes of standard ventilation
MAP \[cm of water / cm H2O\] will be recorded by Servo-tracker software and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
baseline NIV leakage
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
NIV leakage after 15 minutes of heliox
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes of heliox ventilation
NIV leakage after 60 minutes of heliox
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes of heliox ventilation
NIV leakage after 180 minutes of heliox
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes of heliox ventilation
NIV leakage after 15 minutes of standard mixture
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes since the return to ventilation with standard mixture
NIV leakage after 60 minutes of standard mixture
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes since the return to ventilation with standard mixture
NIV leakage after 180 minutes of standard mixture
gas leakage fraction \[%\] during NIV (non-invasive ventilation) recorded by Servo-tracker software their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to ventilation with standard mixture
baseline cerebral oxygenation
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
Cerebral oxygenation after 15 minutes of heliox
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes of heliox ventilation
Cerebral oxygenation after 60 minutes of heliox
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes of heliox ventilation
Cerebral oxygenation after 180 minutes of heliox
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes of heliox ventilation
Cerebral oxygenation after 15 minutes of standard mixture
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes since the return to standard mixture ventilation
Cerebral oxygenation after 60 minutes of standard mixture
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: measured after 60 minutes since the return to standard mixture ventilation
Cerebral oxygenation after 180 minutes of standard mixture
Cerebral tissue oxygen saturation (StO2; \[%\]) measured with near infrared spectroscopy (NIRS) - NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA - their values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to standard mixture ventilation
baseline oxygen requirements
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded at baseline
oxygen requirements after 15 minutes of heliox
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded after 15 minutes of heliox ventilation
oxygen requirements after 60 minutes of heliox
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded after 60 minutes of heliox ventilation
oxygen requirements after 180 minutes of heliox
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded after 180 minutes of heliox ventilation
oxygen requirements after 15 minutes of standard ventilation
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded after 15 minutes since the return to standard mixture ventilation
oxygen requirements after 60 minutes of standard ventilation
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded after 60 minutes since the return to standard mixture ventilation
oxygen requirements after 180 minutes of standard ventilation
Fraction of inspired oxygen (FiO2) will be recorded during heliox and air-oxygen NIV to maintain the saturation assessed by pulse oximetry (SpO2) in 90-95% range; their values will be compared between the phases of the study
Time frame: recorded after 180 minutes since the return to standard mixture ventilation
baseline capillary blood gas analysis
Cobas B 221; Roche, Germany; the values will be compared between the heliox and air-oxygen NIV.
Time frame: blood samples drawn at baseline
capillary blood gas analysis after 3 hours of heliox
Cobas B 221; Roche, Germany; the values will be compared between the heliox and air-oxygen NIV.
Time frame: blood samples drawn after 3 hours of heliox ventilation
capillary blood gas analysis after 3 hours of standard mixture
Cobas B 221; Roche, Germany; the values will be compared between the heliox and air-oxygen NIV.
Time frame: blood samples drawn after 3 hours of standard mixture ventilation
baseline heart rate
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
heart rate after 15 minutes of heliox
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes of heliox ventilation
heart rate after 60 minutes of heliox
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes of heliox ventilation
heart rate after 180 minutes of heliox
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes of heliox ventilation
heart rate after 15 minutes of standard mixture
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 15 minutes since the return to standard mixture ventilation
heart rate after 60 minutes of standard mixture
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 60 minutes since the return to standard mixture ventilation
heart rate after 180 minutes of standard mixture
heart rate (HR, \[bpm / beats per minute\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA), values will be compared between the heliox and air-oxygen NIV.
Time frame: measured after 180 minutes since the return to standard mixture ventilation
baseline oxygen saturation
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured at baseline
oxygen saturation after 15 minutes of heliox
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured 15 minutes after heliox ventilation
oxygen saturation after 60 minutes of heliox
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured 60 minutes after heliox ventilation
oxygen saturation after 180 minutes of heliox
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured 180 minutes after heliox ventilation
oxygen saturation after 15 minutes of standard mixture
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured 15 minutes since the return to standard mixture ventilation
oxygen saturation after 60 minutes of standard mixture
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured 60 minutes since the return to standard mixture ventilation
oxygen saturation after 180 minutes of standard mixture
SpO2 (peripheral capillary oxygen saturation, \[%\]) measured by NONIN Sen Smart Model X-100, Nonin Medical Inc., Plymouth, USA) and the values will be compared between the heliox and air-oxygen NIV.
Time frame: measured 180 minutes since the return to standard mixture ventilation