Obesity, Morbid, Respiratory Failure, Ventilator-Induced Lung Injury
Conditions
Keywords
Transpulmonary pressure, Esophageal balloon, Esophageal pressure monitoring, Mechanical ventilation
Brief summary
This is a research study to determine if identifying an optimal level of positive end-expiratory pressure (PEEP) targeted specifically to individualized patient characteristics will shorten the time on the ventilator. Participants will have catheter placed through the nose into the esophagus to measure the pressure inside the chest. This catheter will remain until the patient is freed from the ventilator. Participants will be randomized to usual care or to have the level of PEEP determined by the esophageal balloon pressure readings. The total time spent on the ventilator will be recorded.
Detailed description
Study Design: Randomized-controlled clinical trial. Patients will be enrolled within 4 days of mechanical ventilation and randomized 1:1 to titration of PEEP based on esophageal balloon pressures or based on the High PEEP ARDSnet PEEP/fraction of inspired oxygen (FiO2) table. All patients will have esophageal balloons placed with baseline measurement of Ptp. Patients randomized to the intervention arm will then undergo titration of PEEP based on Ptp measurements to achieve Optimal PEEP, defined as end expiratory Ptp of 0 to +2 cm water (H2O).
Interventions
DEVICEEsophageal balloon
All patients in both groups will have an esophageal balloon catheter inserted by a research investigator. The catheter will be inserted into their nare while upright (head of bed \>30 degrees) to a depth slightly more than the estimated distance from the lower sternum to the back of the ear (typically around 60 cm). Gastric positioning will be confirmed with abdominal compression testing and the catheter then retracted 10 - 20cm into the lower esophagus. Placement will be confirmed with the presence of cardiac oscillations on the esophageal probe. The probe will then be secured to the patient's nasal opening using tape.
PROCEDUREIntervention Spontaneous Breathing Trial (SBT) and Extubation
Patients in the Intervention group will undergo an SBT regardless of their PEEP level. The PEEP that generates a Ptp of 0 will be considered their optimal PEEP, and this will not be lowered for the SBT. The Intervention Group SBT will consist of a trial of a pressure support of 5 cm H2O and Optimal PEEP.
PROCEDUREControl Spontaneous Breathing Trial and Extubation
Patients in the Control group will undergo an SBT when they reach a PEEP ≤8 cm H2O. This is the current standard of care based on the SBT protocol at UNC Hospitals. SBT and extubation prior to meeting these criteria will be based on primary medical team's discretion and will be recorded for analysis and safety tracking.
PROCEDUREIntervention Weaning after Tracheostomy
Based on the use of optimal PEEP in this group, and the experience in the previous study protocol, the investigators will place patients in the Intervention group on Tracheostomy Collar Trial only with a speaking valve. This simulates the normal process of utilizing the upper airway to maintain lung inflation that is performed automatically when a patient does not have an artificial airway.
PROCEDUREControl Weaning after Tracheostomy
The control group will be placed on Tracheostomy Collar Trial with no requirement for speaking valve. They may utilize a speaking valve if tolerated and desired, but there is no requirement as there is in the Intervention group.
Sponsors
East Carolina University
University of North Carolina, Chapel Hill
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
Due to the obvious treatment differences between the two groups, blinding of treatment group will be impossible. However, the investigators will have one outcome assessor who will have access only to the data necessary to determine the primary outcome (Ventilator-Free Days at 28-days), and this assessor will be blinded to treatment group using built-in REDCap tools.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Body mass index greater than or equal to 40 * Acute respiratory failure requiring mechanical ventilation
Exclusion criteria
* Refusal to give consent by the subject or their legally authorized representative * Abdominal compartment syndrome * Chest tube for pneumothorax * Having been on a ventilator for \>4 days * Suspicion of or known intracranial hypertension * Anticipated extubation within 24 hours * Chronic ventilator dependence * Condition that precludes placement of an esophageal balloon (esophageal or nasopharyngeal pathology preventing insertion of the esophageal balloon catheter, severe thrombocytopenia or coagulopathy) * Incarceration
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Ventilator-Free Days (VFD) by Day 28 | 28 days | The number of days a patient is alive and free from the ventilator up to day 28. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| ICU Length of Stay | maximum duration of ICU stay, up to 46 days | Number of days spent in the ICU |
| Hospital Length of Stay | maximum duration of hospital stay, up to 83 days | Number of days spent in the Hospital |
| Number of Patients Receiving a Tracheostomy | during mechanical ventilation, up to 28 days | Whether the patient required a tracheostomy to be liberated from the ventilator |
| Number of Participants Reintubated | 72 hours after extubation | Intubated within 72 hours of extubation |
| Highest Richmond Agitation and Sedation Scale | during mechanical ventilation, up to 28 days | Measures the mental and physical state of a sedated patient. Range from -5 to +4. A score of 0 indicates a calm arousable patient and is the ideal score. A score of +4 indicates a very combative participant and a score of -5 indicates an unarousable participant. This outcome captures the highest score measured throughout mechanical ventilation with scores on the extreme ends of the range reflecting a worse outcome. |
| Lowest Richmond Agitation and Sedation Scale | during mechanical ventilation, up to 28 days | Measures the mental and physical state of a sedated patient. Range from -5 to +4. A score of 0 indicates a calm arousable patient and is the ideal score. A score of +4 indicates a very combative participant and a score of -5 indicates an unarousable participant. This outcome captures the lowest score measured throughout mechanical ventilation with scores on the extreme ends of the range reflecting a worse outcome. |
| Number of Patients Extubated Early | 28 days | Extubation prior to meeting established criteria (Control group only). Participants in the Control group will undergo an SBT when they reach a PEEP ≤8 cm H2O. This is the current standard of care based on the SBT protocol at UNC Hospitals. SBT and extubation prior to meeting these criteria will be based on primary medical team's discretion and will be recorded for analysis and safety tracking. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Optimal PEEP Obese adult participants presenting to the ICU with acute respiratory failure requiring mechanical ventilation were enrolled. Mechanical ventilation settings were monitored daily and PEEP setting adjusted based on the balloon measurements.
Esophageal balloon: Participants will have an esophageal balloon catheter inserted by a research investigator. The catheter will be inserted into the nare while upright (head of bed \>30 degrees) to a depth slightly more than the estimated distance from the lower sternum to the back of the ear (typically around 60 cm). Placement confirmed with the presence of cardiac oscillations on the esophageal probe. The probe will then be secured to the nasal opening using tape.
Intervention Spontaneous Breathing Trial (SBT) and Extubation: Participants undergo an SBT regardless of PEEP level. The PEEP that generates a Ptp of 0 was considered the optimal PEEP, and this will not be lowered for the SBT. The Intervention Group SBT will consist of a trial of a pressure support of 5 cm H2O and Optimal PEEP.
Intervention Weaning after Tracheostomy: Based on the use of optimal PEEP in this group, and the experience in the previous study protocol, the investigators will place participants in the Intervention group on Tracheostomy Collar Trial only with a speaking valve. This simulates the normal process of utilizing the upper airway to maintain lung inflation that is performed automatically when a participant does not have an artificial airway. | 3 |
| ARDSNet High PEEP Obese adult participants presenting to the ICU with acute respiratory failure requiring mechanical ventilation were enrolled. PEEP in the control group will be determined by High PEEP ARDSnet PEEP/FiO2 table. Titration of PEEP will occur when clinically indicated by partial pressure of oxygen (PaO2) or oxygen saturation (SpO2), and FiO2
Esophageal balloon: Participants will have an esophageal balloon catheter inserted by a research investigator. The catheter will be inserted into the nare while upright (head of bed \>30 degrees) to a depth slightly more than the estimated distance from the lower sternum to the back of the ear (typically around 60 cm). Placement confirmed with the presence of cardiac oscillations on the esophageal probe. The probe will then be secured to the nasal opening using tape.
Control Spontaneous Breathing Trial and Extubation: Participants in the Control group will undergo an SBT when they reach a PEEP ≤8 cm H2O. SBT and extubation prior to meeting these criteria will be based on primary medical team's discretion and will be recorded for analysis and safety tracking.
Control Weaning after Tracheostomy: The control group will be placed on Tracheostomy Collar Trial with no requirement for speaking valve. They may utilize a speaking valve if tolerated and desired, but there is no requirement as there is in the Intervention group. | 3 |
| Total | 6 |
Baseline characteristics
| Characteristic | Optimal PEEP | ARDSNet High PEEP | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 3 Participants | 3 Participants | 6 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 3 Participants | 3 Participants | 6 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 3 Participants | 3 Participants | 6 Participants |
| Region of Enrollment United States | 3 Participants | 3 Participants | 6 Participants |
| Sex: Female, Male Female | 3 Participants | 1 Participants | 4 Participants |
| Sex: Female, Male Male | 0 Participants | 2 Participants | 2 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 3 | 1 / 3 |
| other Total, other adverse events | 3 / 3 | 1 / 3 |
| serious Total, serious adverse events | 2 / 3 | 0 / 3 |
Outcome results
Primary
Number of Ventilator-Free Days (VFD) by Day 28
The number of days a patient is alive and free from the ventilator up to day 28.
Time frame: 28 days
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Optimal PEEP | Number of Ventilator-Free Days (VFD) by Day 28 | 2.33 Days | Standard Deviation 5.86 |
| ARDSNet High PEEP | Number of Ventilator-Free Days (VFD) by Day 28 | 6.67 Days | Standard Deviation 13.32 |
Secondary
Highest Richmond Agitation and Sedation Scale
Measures the mental and physical state of a sedated patient. Range from -5 to +4. A score of 0 indicates a calm arousable patient and is the ideal score. A score of +4 indicates a very combative participant and a score of -5 indicates an unarousable participant. This outcome captures the highest score measured throughout mechanical ventilation with scores on the extreme ends of the range reflecting a worse outcome.
Time frame: during mechanical ventilation, up to 28 days
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Optimal PEEP | Highest Richmond Agitation and Sedation Scale | 2.33 score on a scale | Standard Deviation 0.58 |
| ARDSNet High PEEP | Highest Richmond Agitation and Sedation Scale | 2.00 score on a scale | Standard Deviation 0 |
Secondary
Hospital Length of Stay
Number of days spent in the Hospital
Time frame: maximum duration of hospital stay, up to 83 days
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Optimal PEEP | Hospital Length of Stay | 62.67 Days | Standard Deviation 18.45 |
| ARDSNet High PEEP | Hospital Length of Stay | 33.67 Days | Standard Deviation 29.02 |
Secondary
ICU Length of Stay
Number of days spent in the ICU
Time frame: maximum duration of ICU stay, up to 46 days
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Optimal PEEP | ICU Length of Stay | 37.33 Days | Standard Deviation 7.77 |
| ARDSNet High PEEP | ICU Length of Stay | 24.00 Days | Standard Deviation 18.33 |
Secondary
Lowest Richmond Agitation and Sedation Scale
Measures the mental and physical state of a sedated patient. Range from -5 to +4. A score of 0 indicates a calm arousable patient and is the ideal score. A score of +4 indicates a very combative participant and a score of -5 indicates an unarousable participant. This outcome captures the lowest score measured throughout mechanical ventilation with scores on the extreme ends of the range reflecting a worse outcome.
Time frame: during mechanical ventilation, up to 28 days
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Optimal PEEP | Lowest Richmond Agitation and Sedation Scale | -4.67 score on a scale | Standard Deviation 0.58 |
| ARDSNet High PEEP | Lowest Richmond Agitation and Sedation Scale | -4.67 score on a scale | Standard Deviation 0.58 |
Secondary
Number of Participants Reintubated
Intubated within 72 hours of extubation
Time frame: 72 hours after extubation
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Optimal PEEP | Number of Participants Reintubated | 2 Participants |
| ARDSNet High PEEP | Number of Participants Reintubated | 1 Participants |
Secondary
Number of Patients Extubated Early
Extubation prior to meeting established criteria (Control group only). Participants in the Control group will undergo an SBT when they reach a PEEP ≤8 cm H2O. This is the current standard of care based on the SBT protocol at UNC Hospitals. SBT and extubation prior to meeting these criteria will be based on primary medical team's discretion and will be recorded for analysis and safety tracking.
Time frame: 28 days
Population: This measure only applies to the Control group. These data were not collected for the Optimal PEEP arm.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| ARDSNet High PEEP | Number of Patients Extubated Early | 2 Participants |
Secondary
Number of Patients Receiving a Tracheostomy
Whether the patient required a tracheostomy to be liberated from the ventilator
Time frame: during mechanical ventilation, up to 28 days
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Optimal PEEP | Number of Patients Receiving a Tracheostomy | 1 Participants |
| ARDSNet High PEEP | Number of Patients Receiving a Tracheostomy | 1 Participants |