Acute Hypoxic Respiratory Failure, ARDS, Human, COVID-19 Acute Respiratory Distress Syndrome, COVID-19 Respiratory Infection, Mechanical Ventilation Complication, Respiratory Effort-Related Arousal, Weaning Failure
Conditions
Keywords
ARDS, COVID-19, Weaning from mechanical ventilation, Respiratory drive, Inspiratory effort, Respiratory monitoring
Brief summary
Data comparing respiratory drive and effort in critically ill patients with acute respiratory distress syndrome associated to different severity of COVID-19 penumonia (CARDS) and to other risk factors are lacking. Objectives: To assess respiratory drive and effort of CARDS patients at the first transition from controlled to assisted spontaneous breathing. The second aim was the rate of a composite outcome including the need of higher level of sedation
Detailed description
Multicenter cohort study in four Italian ICU including adults with moderate and severe CARDS (PaO2/FiO2 \<100 mmHg) at ICU admission. An historical cohort of patients with ARDS from various etiologies used for comparison. Respiratory drive (P0.1), diaphragm electrical activity (EAdi), inspiratory effort derived from EAdi (∆PmusEAdi) and from deflection in airway pressure occluded (ΔPocc) (PmusΔPocc), dynamic transpulmonary driving pressure (ΔPL,dyn, the difference between peak and end-expiratory transpulmonary pressure) measured under assisted ventilation. The main ventilatory pattern variables: * Airway Occlusion Pressure (P0.1): Measurement of the decrease in airway pressure during an end-expiratory occlusion. * Pmus-EAdi-derived (∆Pmus, EAdi): Measurement of the pressure generated by the respiratory muscles during inspiration derived by electrical activity of the diaphragm measurements. * Transpulmonary pressure EAdi-derived (∆Plung,dyn): difference between peak and end-expiratory transpulmonary pressure . * Occlusive Pressure Difference (∆Pocc): Evaluation of the pressure difference between the initial and final airway opening during inspiration. * Pmus-∆Pocc-derived (∆Pmus, ∆Pocc): Measurement of the pressure generated by the respiratory muscles during inspiration derived by ∆Pocc (∆Pocc\*0.75) * Transpulmonary driving pressure ∆Pocc derived (∆Plung, ∆Pocc): calculated as (Peak airway pressure -PEEP) - 2/3 \* ∆Pocc * Diaphragmatic Electrical Activity (EAdi): Recording of the electrical activity of the diaphragm. * Peak EAdi (EAdiPEAK): Determination of the highest recorded value of diaphragmatic electrical activity. * Pressure time product of the trans-diaphragmatic pressure per breath and per minute(PTP/min): the integral of Pmusc-EAdi-derived during inspiration per breath. * Inspiratory Delay (ID): Assessment of the time delay between the start of neural inspiration and the onset of mechanical ventilation. * Neuro-ventilatory Efficiency (NVE): Measurement of the efficiency of the neural drive to the respiratory muscles. * Peak Airway Opening Pressure (PawPEAK): Measurement of the peak pressure in the airway during inspiration. * Inspiratory Pressure-Time Product (PmusEAdi/b): Calculation of the work of breathing by integrating the product of diaphragmatic electrical activity and the change in airway pressure during inspiration. * Tidal Volume (VT): Measurement of the volume of air inspired and expired during each breath. * Respiratory Rate: Calculation of the number of breaths per minute delivered by the mechanical ventilator. * Inspiratory and Expiratory Time (Ti,MECH and Te,MECH): Determination of the duration of mechanical inspiration and expiration. * Inspiratory Duty Cycle (TI/TTOT-neur): Calculation of the ratio of inspiratory time to total respiratory cycle time based on neural inspiration.
Interventions
OTHERRespiratory drive and effort assessment
The use of a neurally-adjusted ventilatory assist catheter, the measurement of electrical activity of the diaphragm, ∆Pocc, P0.1, and other ventilatory parameters to assess respiratory drive and effort in three cohorts of patients
Sponsors
University of Turin, Italy
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients with a diagnosis of acute respiratory distress syndrome based on the Berlin criteria. * Patients with ARDS due to confirmed COVID-19 through real-time RT-PCR on nasopharyngeal swabs or lower respiratory tract aspirates. * Patients who had received invasive mechanical ventilation for more than 72 hours. * Patients who were candidates for assisted ventilation. Readiness for assisted ventilation, which was defined by the following criteria: 1. Improvement of the condition leading to acute respiratory failure. 2. Positive end-expiratory pressure lower than 10 cmH2O and inspiratory oxygen fraction lower than 0.5. 3. Richmond agitation sedation scale score between 0 and -3. 4. Ability to trigger the ventilator, i.e., decrease pressure airway opening by more than 3-4 cmH2O during a brief (5-10 seconds) end-expiratory occlusion test. * Hemodynamic stability without vasopressor or inotropes, except for dobutamine and norepinephrine infusion below certain thresholds (dobutamine \<5 gamma/Kg/min and norepinephrine \<0.3 gamma/Kg/min). * Normothermia.
Exclusion criteria
* Patients affected by neurological or neuromuscular pathology and/or known phrenic nerve dysfunction. * Patients with any contraindication to the insertion of a nasogastric tube, such as recent upper gastrointestinal surgery or esophageal varices. * Patients \< 18 years old
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Respiratory drive | 90 breaths | Evaluation of respiratory drive using P0.1 |
| Neuroventilatory coupling | 90 breaths | Evaluation of respiratory drive using EAdi PEAK |
| Respiratory effort | 90 breaths | Evaluation of respiratory drive using ∆Pmus-EAdi derived, ∆Pmus-∆Pocc derived, PTP/min |
| Transpulmonary driving pressure | 90 breaths | Evaluation of respiratory drive using ∆Plung, dynamic |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intensive care unit mortality | Intensive care unit stay | Mortality |
| Mortality | 60 days after measurement | Mortality |
| Composite outcome | within forty eight hour from assisted spontaneous breathing | Transition from light to deep sedation (Richmond agitation sedation scale from 0/-3 to -4/-5) or from assisted to controlled ventilation within 48 hours of spontaneous assisted breathing |
Countries
Italy
Outcome results
None listed