Non-invasive ventilation can allow to avoid intubation and improve outcomes in moderate-to-severe COVID-19-associated acute respiratory distress-syndrome (ARDS). Data on NIV parameters adjustment based on expanded respiratory and gas exchange monitoring in COVID-19 associated ARDS is limited. Appropriate adjustment of the inspiratory positive airway pressure (IPAP) set as a point of the balance between minimal work of breathing (minimum point of W.Patrick scale for assessment of the accessory respiratory muscles and minimum diaphragm thickening fraction) and minimum tidal volume, and respiratory rate can decrease NIV failure in moderate-to-severe COVID-ARDS. The objective of the study is to evaluate the ability of non-invasive ventilation guided with expanded respiratory monitoring to decrease the intubation rate in in moderate-to-severe COVID-ARDS.
In December 2019, an outbreak of a novel coronavirus emerged in Wuhan, China and rapidly
spread worldwide. The World Health Organization (WHO) declared the outbreak a pandemic on
March 11th, 2020. The clinical disease (COVID-19) results in critical illness in about 5% of
patients with predominant acute respiratory failure.
The objective of the study is to evaluate the ability of non-invasive ventilation guided with
expanded respiratory monitoring to decrease the intubation rate in in moderate-to-severe
COVID-ARDS. Investigators will set IPAP as a point of the balance between minimal work of
breathing (minimum point of W.Patrick scale for assessment of the accessory respiratory
muscles, and minimum diaphragm thickening fraction) and minimum tidal volume, and respiratory
rate. Investigators will set expiratory pressure at 8-10 cm of water and the inspiratory
oxygen fraction (FiO2) to reach oxygen saturation by pulse oximetry (SpO2) 95%. All gas
exchange measurements will be set at IPAP level. For gas exchange assessment investigators
will measure partial oxygen tension in the arterial blood (PaO2), partial carbon dioxide
tension in arterial blood (PaCO2), end-tidal carbon dioxide tension (PetCO2), then will
calculate PAO2/FiO2, alveolar dead space (Vd alv) and ventilatory ratio (VR). Investigators
will measure expiratory tidal volume (VT), respiratory rate (RR), peak inspiratory flow (PIF)
and inspiratory time at 3 levels: at the set IPAP, at IPAP+4 cm of water and at IPAP-4 cm of
water. Measurements will be repeated on day 1, 3, 5, 7, 14 and 21 of NIV. NIV failure is
determined as one of the following at set IPAP 26 cm of water and FiO2 100%: fatigue, Patrick
scale 5 points, SpO2<92%, apnoea, hemodynamic instability or Glasgow coma score <14 points.
In patients with NIV failure after intubation and every 7 day after intubation investigators
will measure plateau pressure and calculate the driving pressure at PEEP 8-10-12-14 cm of
water and VT 6 ml/kg predicted body weight (PBW), and VT+100 ml and VT+200 ml at PEEP 8 cm of
water, plot static pressure volume-curve at positive end-expiratory pressure (PEEP) 5 and 14
cm of water, and perform electro impedance tomography.
This study is an observational trial in the ICU of the University hospital.
Diagnostic Test: Respiratory monitoring
Measurement of the tidal volume, peak inspiratory flow, inspiratory time, respiratory rate and the pressure gap during triggering on NIV and plateau pressure on mechanical ventilation
Diagnostic Test: Respiratory muscles ultrasound
Measurement of the diaphragm thickening fraction, assessment of the contraction of scalene and sternocleidomastoid muscles
Diagnostic Test: Electro impedance tomography
Measurement of the lung impedance changes in 4 quadrants, measurement of regional ventilation delay in 4 quadrants
Diagnostic Test: Capnography
Measurement of end-tidal carbon dioxide tension
Diagnostic Test: Arterial blood gas
Measurement of the oxygen partial pressure and the carbon dioxide partial pressure
Diagnostic Test: Quasistatic pressure-volume curve
Quasistatic pressure-volume curve
Inclusion Criteria:
- at least one of the following criteria: fatigue, Patrick scale 5 points, SpO2<92% on
standard oxygen therapy (<15 l/min) or continuous positive airway pressure
(CPAP)-therapy with oxygen flow<15 l/min
Exclusion Criteria:
- pregnancy
- age less than 18 or more than 80 years
- life-threatening heart rhythm abnormalities and/or systolic blood pressure < 80 mmHg
despite norepinephrine at a dose > 2 µg/kg/min
- primary lung diseases (e.g. interstitial lung diseases, lung emphysema) or tumour
metastases in lungs
- chronic decompensated diseases with extrapulmonary organ dysfunction (tumour
progression, liver cirrhosis, congestive heart failure)
- Glasgow cona score < 14
- inability to swallow
- upper airways obstruction
Sechenov University clinic #4
Moscow, Russian Federation
Andrey I Yaroshetskiy, MD, PhD, ScD, Principal Investigator
Sechenov University