An observational study in Mechanical Ventilation Complication, Diaphragm Injury and Lung Injury, sponsored by University Health Network, Toronto. Recruiting at 1 site in Canada. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2024-05-21.
Sponsored by University Health Network, Toronto · Observational
Air is normally pumped in and out of the lungs by the muscles that contribute to inhalation and exhalation, called the respiratory muscles. The abdominal muscles help by forcing air out of your lungs during exhalation; whereas the diaphragm, the main muscle used for breathing, contracts to get air into the lungs during inhalation. With mechanical ventilation, respiratory muscles are able to rest and recover while the breathing machine takes over; however, this may cause respiratory muscle weakness. Patients who develop weakness of these muscles may require more assistance from the ventilator and take longer to recover their ability to breathe without assistance. The impact of this phenomenon on long-term outcomes is uncertain.
The RESPIRE study is designed to characterize how respiratory muscles change during mechanical ventilation and to evaluate the impact on long term quality of life. An additional objective of this study is to examine novel measures obtained from automated functions of a ventilator, that may better predict success from weaning from mechanical ventilation.
Previous work has established that diaphragm atrophy during mechanical ventilation is associated with adverse clinical outcomes. Abdominal muscles, which are engaged during breathing also undergo atrophy during mechanical ventilation. However, the relationship between these muscles and how they relate to long term function status is known and warrants further investigation.
Mechanical ventilation is a life-saving technique in patients with respiratory failure, however reasons why some patients require long term ventilation and are unsuccessful from weaning from ventilators are not fully elucidated. Respiratory muscle dysfunction as a result of mechanical ventilation is only recently being understood. Diaphragm atrophy is associated with adverse clinical outcomes, but the same is unknown if this holds true with abdominal muscle atrophy. Properly understanding the natural progression of diaphragm and abdominal muscle atrophy and dysfunction, and how they relate to each other, is critical to identifying markers or factors that may put particular patients at risk for long durations of mechanical ventilation and adverse clinical outcomes.
This study will provide important insights into the relationship between inspiratory and expiratory muscle function, and the evolution of functional impairments in critical care patients undergoing weaning from invasive mechanical ventilation. Further understanding of the pathophysiological processes of how these muscle groups interact in this context is important in moving forward with potential therapeutic strategies aimed at mitigating injury.
399 studies on the registry are indexed under Lung Injury; 50 are open to participants now.
This study's planned enrollment of 230 is above the median of 70 across 136 observational studies indexed under Lung Injury.
Browse Lung Injury studies →University Health Network, Toronto is the lead sponsor of 1,411 studies on the registry; 292 are open to participants now.
Of its 17 completed or terminated interventional studies of FDA-regulated products, 3 (18%) have results posted.
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Patients will be enrolled in the Medical-Surgical ICU at Toronto General Hospital.
Cases Inclusion Criteria:
Control condition A Inclusion Criteria:
Control condition B Inclusion Criteria
Exclusion Criteria:
Adult patients ≥18 years of age undergoing invasive mechanical ventilation in the ICU for any reason within 36 hours of intubation
Other: Sonographic measurements · Other: Physiological measurements · Other: Biological measurements
Non-invasively ventilated patients in the ICU within 36 hours of initiating non-invasive ventilation
Other: Sonographic measurements · Other: Physiological measurements · Other: Biological measurements
Non-ventilated patients admitted to the ICU receiving no respiratory support or oxygen therapy alone, including high flow nasal cannula
Other: Sonographic measurements · Other: Physiological measurements · Other: Biological measurements
Diaphragm thickness, diaphragm tidal thickening fraction, abdominal muscle thickness, rectus femoris cross-sectional area, maximal diaphragm thickening fraction, abdominal muscle thickening fraction
Airway occlusion pressure, maximal inspiratory pressure, muscle research council score
Skeletal troponin-I
Quality of life at home
5-level EQ-5D (EQ-5D-5L) score - The EQ-5D-5L is a validated self-reported instrument assessing quality of life at the moment questionnaire is completed. Each question is scored from 1 (no problems) to 5 (inability to perform activity) and are independently assessed.
Time frame: Day 180
Quality of life at home
Montreal Cognitive Assessment (MOCA) score - MoCA is a clinician-reported measure to assess for cognitive impairments. MoCA is scored out of 30 with scores \<26 indicating cognitive impairment.
Time frame: Day 180
Duration of ventilation
Time frame: Until hospital discharge (up to 6 months)
Muscle research council score
Muscle research council score, is a validated measure of muscle strength. Possible scores range from 0 (complete paralysis) to 60 (normal strength). Assessments will be made at first spontaneous breathing trial \& at day 14.
Time frame: Until day 14
Airway occlusion pressure (P0.1)
P0.1 will be assessed during spontaneous breathing trial. Spontaneous breathing trials (SBT) are standard of care to assess if patients are able to be extubated from mechanical ventilation. A specific time frame cannot be provided as SBT are only conducted when care team deem the patient as capable.
Time frame: First spontaneous breathing trial (within 5 minutes of onset)
Expiratory occlusion pressure (Pocc)
Pocc will be assessed during spontaneous breathing trial. Spontaneous breathing trials (SBT) are standard of care to assess if patients are able to be extubated from mechanical ventilation. A specific time frame cannot be provided as SBT are only conducted when care team deem the patient as capable.
Time frame: First spontaneous breathing trial (within 5 minutes of onset)
Maximal inspiratory pressure (MIP)
MIP will be assessed during spontaneous breathing trial. Spontaneous breathing trials (SBT) are standard of care to assess if patients are able to be extubated from mechanical ventilation. A specific time frame cannot be provided as SBT are only conducted when care team deem the patient as capable.
Time frame: First spontaneous breathing trial within 30 minutes of onset
Days alive and at home at 180 days post ICU discharge
Time frame: Day 180
Changes in abdominal muscle thickening fraction during cough
Abdominal muscle thickening fraction during cough will be assessed by ultrasound during SBT when care team deems patient capable and safe to do so, as such a specific time frame for SBT cannot be provided. Additionally abdominal muscle thickening fraction will be assessed at ICU discharge. A specific time frame cannot be provided as ICU discharge will vary between patients.
Time frame: At first spontaneous breathing trial within 30 minutes of onset and at ICU discharge, an average of 7 days
Maximal diaphragm thickening fraction
Maximal diaphragm thickening fraction will be assessed by ultrasound during SBT when care team deems patient capable and safe to do so, as such a specific time frame for SBT cannot be provided. Additionally abdominal muscle thickening fraction will be assessed at ICU discharge. A specific time frame cannot be provided as ICU discharge will vary between patients.
Time frame: At first spontaneous breathing trial within 30 minutes of onset and at ICU discharge, an average of 7 days
Changes in resting abdominal muscle thickening
Diaphragm ultrasound to measure thickening of abdominal muscles during resting tidal breathing.
Time frame: Until Day 14
Changes in resting thickening fraction
Diaphragm ultrasound to measure thickening fraction during resting tidal breathing.
Time frame: Until Day 14
Plan to share: No
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University Health Network, Toronto