Trial Outcomes & Findings for Electrical Impedance Tomography for Optimization of Positive End-Expiratory Pressure: Acute Respiratory Distress Syndrome (NCT NCT03793842)

NCT ID: NCT03793842

Last Updated: 2023-10-12

Results Overview

Mechanical power (MP) is the energy imparted to the lung from the mechanical ventilator. It is calculated as listed below, where respiratory rate = RR, tidal volume = TV, Ppeak = peak airway pressure, Pplat = plateau airway pressure and PEEP = positive end-expiratory pressure. Mechanical power determined for the difference between Treatment 1 and Treatment 2. Values shown represent data gathered at the end of the designated assignment listed below, regardless of whether that assignment was Treatment 1 or Treatment 2. MP = 0.098 X RR X TV (Ppeak-\[Pplat-PEEP/2\])

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

16 participants

Primary outcome timeframe

Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at end of treatment.

Results posted on

2023-10-12

Participant Flow

Participant milestones

Participant milestones
Measure
Usual Care Then Positive End-Expiratory Pressure (PEEP) Titration by EIT
Patients in the usual care first group will continue to receive mechanical ventilation according to the University of Michigan Acute Respiratory Distress Syndrome (ARDS) protocol high-PEEP arm. Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine. PEEP titration by Electrical Impedance Tomography (EIT): PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Positive End-Expiratory Pressure (PEEP) Titration by EIT Then Usual Care
Patients in the high PEEP titration by Electrical Impedance Tomography (EIT) first will have receive ventilation with a PEEP determined by EIT titration procedure. Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine. PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Randomization-Intervention 1 (~6 Hrs)
STARTED
8
8
Randomization-Intervention 1 (~6 Hrs)
Intervention 1 Started
6
6
Randomization-Intervention 1 (~6 Hrs)
COMPLETED
6
6
Randomization-Intervention 1 (~6 Hrs)
NOT COMPLETED
2
2
Intervention 2 (14-18 Hours)
STARTED
6
6
Intervention 2 (14-18 Hours)
COMPLETED
6
6
Intervention 2 (14-18 Hours)
NOT COMPLETED
0
0

Reasons for withdrawal

Reasons for withdrawal
Measure
Usual Care Then Positive End-Expiratory Pressure (PEEP) Titration by EIT
Patients in the usual care first group will continue to receive mechanical ventilation according to the University of Michigan Acute Respiratory Distress Syndrome (ARDS) protocol high-PEEP arm. Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine. PEEP titration by Electrical Impedance Tomography (EIT): PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Positive End-Expiratory Pressure (PEEP) Titration by EIT Then Usual Care
Patients in the high PEEP titration by Electrical Impedance Tomography (EIT) first will have receive ventilation with a PEEP determined by EIT titration procedure. Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine. PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Randomization-Intervention 1 (~6 Hrs)
Physician Decision
0
1
Randomization-Intervention 1 (~6 Hrs)
Prone positioning after baseline data collection
2
1

Baseline Characteristics

Electrical Impedance Tomography for Optimization of Positive End-Expiratory Pressure: Acute Respiratory Distress Syndrome

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Usual Care Then PEEP Titration by EIT
n=6 Participants
Patients in the usual care first group will continue to receive mechanical ventilation according to the University of Michigan ARDS protocol high-PEEP arm Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine. PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
PEEP Titration by EIT Then Usual Care
n=6 Participants
Patients in the high PEEP titration by EIT first will have receive ventilation with a PEEP determined by EIT titration procedure. Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine. PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Excluded
n=4 Participants
Patients in this arm were excluded per protocol.
Total
n=16 Participants
Total of all reporting groups
Age, Continuous
59.5 years
n=5 Participants
62 years
n=7 Participants
67 years
n=5 Participants
60.5 years
n=4 Participants
Sex: Female, Male
Female
2 Participants
n=5 Participants
1 Participants
n=7 Participants
3 Participants
n=5 Participants
6 Participants
n=4 Participants
Sex: Female, Male
Male
4 Participants
n=5 Participants
5 Participants
n=7 Participants
1 Participants
n=5 Participants
10 Participants
n=4 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
2 Participants
n=4 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
5 Participants
n=5 Participants
6 Participants
n=7 Participants
3 Participants
n=5 Participants
14 Participants
n=4 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Black or African American
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
White
5 Participants
n=5 Participants
6 Participants
n=7 Participants
3 Participants
n=5 Participants
14 Participants
n=4 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
0 Participants
n=4 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
2 Participants
n=4 Participants
Region of Enrollment
United States
6 Participants
n=5 Participants
6 Participants
n=7 Participants
4 Participants
n=5 Participants
16 Participants
n=4 Participants

PRIMARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at end of treatment.

Population: 3 participants in whom prone ventilation was initiated were excluded. 1 additional participant was excluded due to physician withdrawal from the trial. The remaining participants received invasive mechanical ventilation in the supine position for the duration of the protocol.

Mechanical power (MP) is the energy imparted to the lung from the mechanical ventilator. It is calculated as listed below, where respiratory rate = RR, tidal volume = TV, Ppeak = peak airway pressure, Pplat = plateau airway pressure and PEEP = positive end-expiratory pressure. Mechanical power determined for the difference between Treatment 1 and Treatment 2. Values shown represent data gathered at the end of the designated assignment listed below, regardless of whether that assignment was Treatment 1 or Treatment 2. MP = 0.098 X RR X TV (Ppeak-\[Pplat-PEEP/2\])

Outcome measures

Outcome measures
Measure
PEEP
n=12 Participants
PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Usual Care
n=12 Participants
Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine.
Mechanical Power
1.87 J/min
Standard Deviation 1.61
-2.50 J/min
Standard Deviation 3.7

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at baseline and end of treatment.

P/F ratio is a measurement of oxygenation and, where arterial oxygen in mmHg is PaO2 and percentage of inspired oxygen is FiO2. It calculated as: PaO2/FiO2. P/F ratio determined for the difference between Intervention 1 and Intervention 2

Outcome measures

Outcome measures
Measure
PEEP
n=12 Participants
PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Usual Care
n=12 Participants
Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine.
Change in Lung Inflammation as Measured by Physiologic Parameter: Partial Pressure of Arterial Oxygen/Fraction of Inspired Oxygen (P/F Ratio)
25.14 ratio
Standard Deviation 27.11
-0.89 ratio
Standard Deviation 60.05

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at baseline and end of treatment.

Plateau pressure is a measurement of lung compliance and is the airway pressure obtained during a brief inspiratory hold after delivering a tidal volume breath during invasive mechanical ventilation. Plateau pressure determined for the difference between Intervention 1 and Intervention 2

Outcome measures

Outcome measures
Measure
PEEP
n=12 Participants
PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Usual Care
n=12 Participants
Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine.
Change in Lung Inflammation as Measured by Physiologic Parameter: Plateau Pressure
2.06 cm H2O
Standard Deviation 1.88
-2.48 cm H2O
Standard Deviation 3.22

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at end of treatment.

Population: ARDS patients

Driving pressure is the force of airway push into the lung while receiving invasive mechanical ventilation and is calculated as Plateau pressure - Positive end-expiratory pressure. Driving pressure determined for the difference between Intervention 1 and Intervention 2

Outcome measures

Outcome measures
Measure
PEEP
n=12 Participants
PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Usual Care
n=12 Participants
Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine.
Lung Inflammation as Measured by Physiologic Parameter: Driving Pressure
1.34 cm H2O
Standard Deviation 1.31
-1.58 cm H2O
Standard Deviation 2.32

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at baseline and end of treatment.

Static lung compliance is a measurement of lung stiffness due to disease, with a lower compliance representing stiffer lungs. It is calculated as: Tidal volume / (Plateau pressure - PEEP). Static compliance determined for the difference between Intervention 1 and Intervention 2

Outcome measures

Outcome measures
Measure
PEEP
n=12 Participants
PEEP titration by EIT: PEEP Titration procedure involves two phases: a recruitment phase followed by a gradual reduction in the end-expiratory pressure phase (Decremental PEEP).
Usual Care
n=12 Participants
Usual care: Intervention is the standard basic lung protective ventilation strategy used at the University Hospital Respiratory Care at Michigan Medicine.
Change in Lung Inflammation as Measured by Physiologic Parameter: Static Compliance
3.24 ml/cm H2O
Standard Deviation 9.85
-4.6 ml/cm H2O
Standard Deviation 5.26

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at end of treatment.

Population: No PaO2 data was obtained or recorded as such. Physicians directly calculated PaO2/FiO2 data shown above in Outcome Measure 2.

PaO2 is the partial pressure of arterial oxygen measured in mmHg. PaO2 determined for the difference between Intervention 1 and Intervention 2.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at end of treatment.

Population: Dynamic compliance was not recorded due to the attempt of investigative personnel to limit time exposure to Coronavirus disease 19 (COVID-19) in most study participants.

Dynamic compliance is a measurement of the resistance of the lungs and airways to gas installation from the mechanical ventilator and is measured as Peak airway pressure / Plateau airway pressure - PEEP). Dynamic compliance determined for the difference between Intervention 1 and Intervention 2.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at baseline and end of treatment.

Population: C20/Dyn was not recorded due to the attempt of investigative personnel to limit time exposure to COVID-19 in most study participants.

C20 is the compliance that results when only the upper 20% of the applied pressure range is taken into account. The C20/Dyn ratio appears to effectively quantitate evidence of lung over distention during mechanical ventilation. This is a unit-less measure as both numerator and denominator are measured in cm water. C20/dyn determined for the difference between Intervention 1 and Intervention 2.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Participants received Treatment 1 (either Usual Care or PEEP EIT) for approximately 6 hours after randomization and then received Treatment 2 for an additional 14-18 hours following crossover. Measurement was done at end of treatment.

Population: Lung ultrasound was not recorded due to the attempt of investigative personnel to limit time exposure to COVID-19 in most study participants.

Lung ultrasound inflation scores are calculated by summing regional scores (0-3 points), with higher scores indicating worse condition of the lung. Scores were obtained in six regions of each lung (i.e., up and down anterior, medial, and posterior chest wall). This is a unit-less measure. Ultrasound lung surrogates of lung inflation determined for the difference between Intervention 1 and Intervention 2.

Outcome measures

Outcome data not reported

Adverse Events

Usual Care

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

PEEP

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Robert Hyzy, MD

Michigan Medicine

Phone: 734-936-5201

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place