Lung Impedetiometric Modification in SBT and Extubation Failure (CPAP2-EIT)

University Magna Graecia

Status: Completed

Conditions: Weaning Failure; Mechanical Ventilation Complication

Treatments: Diagnostic Test: Electrical Impedance Tomography (EIT)

Study type: Observational

Funder types: Other

Identifiers

NCT03894332

CPAP2EIT

Details and patient eligibility

About

Weaning is the entire process aimed at liberating patients from mechanical ventilation and endotracheal intubation. Weaning should be considered as early as possible in order to reduce the time spent in invasive mechanical ventilation (iMV), which is associated with morbidity and mortality. To verify if patients are ready to be extubated, a spontaneous breathing trial (SBT) is performed. At this stage some clinical indices and objective parameters are evaluated, such as the breathing pattern, gas exchange, haemodynamic stability and patient's comfort. In case of SBT success, the patient can be extubated. However, a post-extubation respiratory failure can occur within the first 48 hours after extubation, thus making extubation unsuccessful. Some patients considered at risk for post-extubation respiratory failure benefit from the application of non-invasive ventilation (NIV) after extubation. Early characterization of these patients is crucial to improve their clinical outcomes.

Electrical Impedance Tomography (EIT) has been introduced in clinical practice as a non-invasive bedside monitoring tool to evaluate the aeration and ventilation of different lung regions. EIT has been proposed to guide ventilator settings adjustments in critically ill patients and to monitor prolonged weaning. However, the potential of EIT to assess SBT and after extubation in a general ICU population has never been evaluated insofar.

The present study aims to describe the modifications of lung aeration, ventilation and inhomogeneity occurring during SBT and after extubation in a general population of critically ill patients at the first SBT attempt.

Enrollment: 80 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Glasgow Coma Scale ≥8
• presence of clearly audible cough during suctioning with need for tracheal suctioning ≤2/hour
• normal sodium blood values
• core temperature <38.5° during the previous 8 hours
• Arterial partial pressure of oxygen to inspired oxygen fraction (PaO2/FiO2) ≥200 mmHg, with a Positive End Expiratory Pressure ≤5 cmH2O and FiO2 ≤0.4
• stable cardiovascular status (i.e., HR ≤140 beats/min, sBP between 90 and 160 mmHg without need for vasopressin, epinephrine or norepinephrine infusion, or with dopamine or dobutamine infusion ≤5 mcg/kg/min)
• cuff leak volume >110 mL

Exclusion criteria

• major heart arrhythmias or cardiac ischemia
• pneumothorax or emphysema
• recent (1 week) thoracic surgery
• presence of chest burns
• pregnancy
• inclusion in other research protocols

Trial design

80 participants in 4 patient groups

SBT Success

Description:

Patients took part of this cohort when succeeding the Spontaneous Breathing Trial (SBT).

Treatment:

Diagnostic Test: Electrical Impedance Tomography (EIT)

SBT Failure

Description:

Patients took part of this cohort when failing the Spontaneous Breathing Trial (SBT). SBT Failure is defined by one or more of the following criteria occurring during the SBT: 1. loss of ≥ 2 points of Glasgow Coma Scale 2. respiratory rate/ tidal volume ≥105 breaths/min/L 3. arterial partial pressure of oxygen ≤60 mmHg on inspired oxygen fraction (FiO2) ≥0.5 and/or pH \<7.32 or a decrease in pH ≥0.07 units at the end of the SBT 4. systolic Blood Pressure \<90 mmHg or ≥180 mmHg or increased by ≥20% 5. Heart Rate \>140 beats/min or increased by 20% 6. onset of major heart arrhythmias, or electrocardiographic signs of cardiac ischemia 7. Respiratory Rate ≥35 breaths/min or increased by ≥50% 8. increased effort, respiratory distress (as indicated by diaphoresis, accessory respiratory muscles recruitment, facial signs of distress and/or paradoxical breath)

Treatment:

Diagnostic Test: Electrical Impedance Tomography (EIT)

Extubation Success

Description:

Patients took part of this cohort when, after extubation, did not need continuous positive airways pressure (CPAP), non invasive ventilation (NIV) or reintubation within 48 hours.

Treatment:

Diagnostic Test: Electrical Impedance Tomography (EIT)

Extubation Failure

Description:

Need for continuous positive airways pressure (CPAP), non invasive ventilation (NIV) or reintubation within 48 hours from extubation, as defined by: 1. Respiratory Rate \>25 breaths/min for 2 hours 2. Heart Rate \>140 beats/min or sustained increase or decrease \>20% 3. clinical signs of respiratory muscle failure 4. arterial partial pressure of oxygen (PaO2) \<80 mmHg on inspired oxygen fraction (FiO2) ≥50% 5. Arterial partial pressure of carbon dioxide \>45 mmHg with pH \<7.33

Treatment:

Diagnostic Test: Electrical Impedance Tomography (EIT)