COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC:

Get the latest research information from NIH: Menu
Trial record 1 of 1 for:    Incidence of dyssynchronous spontaneous Breathing Effort, breath-stacking and reverse triggering in early ARDS
Previous Study | Return to List | Next Study

Incidence of Dyssynchronies in Early ARDS (BEARDS)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03447288
Recruitment Status : Recruiting
First Posted : February 27, 2018
Last Update Posted : April 4, 2019
Information provided by (Responsible Party):
St. Michael's Hospital, Toronto

Brief Summary:

Patients sedated under mechanical ventilation with acute hypoxemic respiratory failure with a PaO2/FiO2 equal or less than 200mmHg (Acute Respiratory Distress Syndrome, ARDS and non-ARDS) will be included in the study early in the course of the disease (first week of mechanical ventilation). At enrollment, data on the clinical condition of the patient will be recorded together with ventilation settings: ventilation mode, the fraction of inspired oxygen (FiO2), PEEP, tidal volume, set pressure, respiratory rate, time of the respiratory cycle, recent blood gas parameters.

Airway pressure, flow, and esophageal pressure (or alternatively electrical activity of the diaphragm, Eadi) will be recorded 3 times a day for 7 days:

  1. Period 1 (morning): duration 20-30 minutes
  2. Period 2 (afternoon): duration 20-30 minutes
  3. Period 3 (evening / night): duration 20-30 minutes

Registration will be ended at extubation, death or at eight days from the first recording.

Monitoring of vital parameters (hemodynamic and respiratory) will be continuous throughout the duration of the study, as per normal clinical practice. All drugs used during the day of the measurements will be recorded. The patient will then be followed until discharge from the ICU and after 60 days of discharge to evaluate mortality.

The analysis of the recorded waveforms will be performed in a single center by a centralized system that will quantify dyssynchrony and its intensity, calculate pressure time product, collect clinical and physiological data and outcome, and investigate possible correlations.

Condition or disease
ARDS Acute Hypoxemic Respiratory Failure

Detailed Description:


Physiological measurements Airway pressure, esophageal pressure, electrical activity of the diaphragm and flow

  1. Flow and airway pressure signal will be recorded from the ventilators by connecting the ventilator to a laptop computer if possible. Recording these data simultaneously with esophageal pressure or electrical activity of the diaphragm (see later in protocol for details) could be technically unfeasible. In this case, a flow sensor and an additional port for pressure measurement will be connected to the endotracheal tube proximal to the Y connector (without interfering with patient's breathing). Both, flow sensor and pressure port will be connected to differential pressure transducers respectively. Signals will be acquired with at least 100 Hz sampling.
  2. In centers used to perform esophageal pressure measurements, an esophageal catheter will be inserted as per usual clinical practice, checked for accuracy with an occlusion test, and connected to a 3 ways stopcock and a pressure transducer. The occlusion test will be recorded and performed before any new recordings. Any ventilator can be used if an esophageal pressure is used.
  3. If available, in centers used to record or monitor the electrical activity of the diaphragm, instead of an esophageal catheter, the electrical activity of the diaphragm will be provided by a catheter dedicated to the monitoring of the electrical activity of the diaphragm, or EaDi, on a Servo-I or Servo-U ventilator (Maquet©, Lund, Sweden). This catheter is formally designed to be used for a specific mode of ventilation called Neurally Adjusted Ventilatory Assist (NAVA) but here will be used for monitoring purposes only (NAVA catheter). In such cases a specific software (Servotracker, Maquet) may be used to record all signals from the ventilator.
  4. In case the patient has been enrolled but the esophageal catheter cannot be placed or is contraindicated, the recordings will be limited to airway pressure and flow. Each centre should have a minimum of 5 patients with esophageal catheter or electrical activity recording.
  5. Occlusion pressure (or pressure at 0.1 sec, P0.1) as an index of respiratory drive. In patients triggering the ventilator, the P0.1 will be analyzed from the tracings. The only condition to have reliable measurements is to use a pressure triggering, not a flow triggering.

Data collection

At the beginning of the recordings, ventilatory settings will be collected: ventilator brand, mode of ventilation and settings including: FiO2, PEEP, set and real tidal volume (or pressure), set and real respiratory rate, maximum inspiratory flow, inspiratory time, Glasgow coma scale and Richmond Agitation Sedation Scale (RASS) or Riker Sedation Agitation Scale (SAS). Any medications used at the day of the measurement and before will be collected especially neuromuscular blocking agents, sedatives (brands and doses), opiates and vasopressors including dose, duration of the treatment and date of last use. Investigators will also collect clinical characteristics of the patients (SAPS and SOFA at ICU admission and at the day of the recording, main ARDS or AHRF etiology and risk factors, age, gender, weight, height, days of mechanical ventilation, patient's position -supine vs prone-, kidney and liver function). Other comorbidities will be recorded, with special emphasis in the ones that could affect the incidence of the studied phenomenon, such as: COPD, lung transplant or any neuromuscular condition that could affect the respiratory drive or respiratory muscle function.

Patients will be followed up to get the total duration of mechanical ventilation, ICU length of stay, day of the first weaning attempt, day of tracheotomy if any, status at ICU discharge (alive or death) and at hospital discharge and at day 60.

Layout table for study information
Study Type : Observational [Patient Registry]
Estimated Enrollment : 300 participants
Observational Model: Cohort
Time Perspective: Prospective
Target Follow-Up Duration: 60 Days
Official Title: Incidence of Dyssynchronous Spontaneous Breathing Effort, Breath-stacking and Reverse Triggering in Early ARDS
Actual Study Start Date : January 15, 2017
Estimated Primary Completion Date : August 2020
Estimated Study Completion Date : August 2020

Primary Outcome Measures :
  1. Prevalence of dyssynchrony [ Time Frame: Within 1 Year ]

    For each patients, the number of dyssynchrony (reverse triggering, breath stacking, short cycles) will be counted over the recorded period. An asynchrony index, (number of dyssynchrony divided by the total number of breaths) as well as the number of dyssynchrony per minute will be calculated globally and for each dyssynchrony type.

    Patients with ARDS will be compared to patients with AHRF. Patients with severe ARDS or severe AHRF (<120) will be compared to less severe patients.

Secondary Outcome Measures :
  1. Intensity of dyssynchrony [ Time Frame: Within 1 Year ]
    Assessement of the frequency and magnitude of effort assessed by esophageal pressure or electrical activity of he diaphragm for each type of dyssynchrony

  2. Correlation of clinical outcome with intensity of dyssynchrony [ Time Frame: Within 1 Year ]

    Outcomes will be the duration of mechanical ventilation (in days); the number of ventilator-free days at day 28 (number of days alive without mechanical ventilation in 28 days; death equals 0 ventilator-free days); ICU survival and hospital survival. For each type of dyssynchrony, the outcomes will be correlated with the intensity of dyssynchrony.

    Intensity of dyssynchrony will be based on the dyssynchrony index above a minimal level of effort for each dyssynchrony.

    The outcomes above several thresholds of dyssynchrony index (10%, 30%, 50%) will be compared.

  3. Impact of reverse triggering on breathing effort [ Time Frame: Within 1 Year ]
    The breathing effort (pressure-time product) will be calculated and its value will be compared for breaths with and without reverse triggering.

  4. Quantification of spontaneous breathing efforts associated with dyssynchronies. [ Time Frame: Within 1 Year ]
    For each dyssynchrony found, the effort measured by the pressure-time product using esophageal pressure will be calculated. And the clinically relevant dyssynchronies will be determined based on a minimal amount of effort.

  5. Association between pH and Dyssynchrony [ Time Frame: Within 1 Year ]
    Arterial pH will be compared at different values of dyssynchrony index above a minimal level (10%, 30% and 50%).

  6. Association between sedation and Dyssynchrony [ Time Frame: Within 1 Year ]
    Level of sedation (assessed either Sedation Agitation Score "SAS" or the Richmond Agitation and Sedation Scale "RASS") by the will be compared at different values of dyssynchrony index above a minimal level (10%, 30% and 50%).

  7. Association between sedatives and Dyssynchrony [ Time Frame: Within 1 Year ]
    Values of dyssynchrony index above a minimal level will be compared between patients receiving primarily propofol versus benzodiazepines.

  8. Clusters of dyssynchronies [ Time Frame: Within 1 Year ]
    Timing of detection of dyssynchrony

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Patients with moderate to severe acute hypoxemic respiratory failure (ARDS and non-ARDS) under sedation and mechanical ventilation.

Inclusion Criteria:

  • Moderate and severe ARDS and AHRF, according to the Berlin definition. The absence of the Chest X-Ray criterion (e.g. unilateral disease) or the presence of primary cardiac dysfunction will define AHRF.
  • Continuous intravenous sedation
  • Deep sedation: Richmond Agitation Sedation Scale (RASS) ≤ -3 or Riker Sedation-Agitation Scale (SAS) ≤ 3

Exclusion Criteria:

  • <18 years
  • Patients with a significant bronchopleural fistula
  • Pure COPD exacerbation
  • Patients on chronic home ventilation

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03447288

Layout table for location contacts
Contact: Laurent Brochard, Dr. 416-864-6060 ext 5686
Contact: Tài Pham, Dr. 647-643-29808

Layout table for location information
Canada, Ontario
St Michael's hospital Recruiting
Toronto, Ontario, Canada, M5B 1W8
Contact: Tài Pham, Md, PhD    647-643-2808   
Toronto General Hospital Not yet recruiting
Toronto, Ontario, Canada, M5G 2C4
Contact: Ewan C. Goligher, MD, FRCP(C)    416-586-8449   
Beijing Tiantan Hospital, Capital Medical University Not yet recruiting
Beijing, China, 100050
Contact: Jian-Xin Zhou, MD   
Centre Hospitalier Universitaire - CHU Angers Not yet recruiting
Angers, France, 49933
Contact: Alain Mercat, MD    33241353815   
Universitätsklinikum Schleswig-Holstein Recruiting
Kiel, Germany, 24105
Contact: Tobias Besher, MD   
University Hospital of Heraklion Recruiting
Heraklion, Greece, 711 10
Contact: Dimitris Georgopoulos, MD   
Contact: Eumorfia Kondili, MD   
University of Ferrara Recruiting
Ferrara, Italy
Contact: Savino Spadaro, MD   
Azienda Ospedaliero - Universitaria OORR Ospedali Riuniti di Foggia Not yet recruiting
Foggia, Italy, 71122
Contact: Gilda Cinnella, MD    +39 0881 73 23 07   
ASST Santi Paolo e Carlo Recruiting
Milano, Italy
Contact: Davide Chiumello, Pr.    02 81844020   
Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Recruiting
Milano, Italy
Contact: Tommaso Mauri, MD   
VU University Medical Centre Amsterdam Recruiting
Amsterdam, Netherlands, 1007 MB
Contact: Leo Heunks, Pr.    +31 20 4443924   
Contact: Heder de Vries, Dr.   
Vall d'Hebron University Hospital Recruiting
Barcelona, Spain
Contact: Oriol Roca, MD   
National Cheng-Kung University and Hospital Recruiting
Tainan City, Taiwan, 704
Contact: cwchen chen, MD   
Siriraj Hospital Recruiting
Bangkok, Thailand, 10700
Contact: Nuttapol Rittayamai, MD   
Sponsors and Collaborators
St. Michael's Hospital, Toronto
Layout table for investigator information
Principal Investigator: Laurent Brochard, Dr. St. Michael's Hospital, Toronto
Additional Information:

Layout table for additonal information
Responsible Party: St. Michael's Hospital, Toronto Identifier: NCT03447288    
Other Study ID Numbers: 17-182
First Posted: February 27, 2018    Key Record Dates
Last Update Posted: April 4, 2019
Last Verified: April 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided
Plan Description: We plan to share physiologic tracings with no participant identification.
Keywords provided by St. Michael's Hospital, Toronto:
Reverse Triggering
Mechanical Ventilation
Additional relevant MeSH terms:
Layout table for MeSH terms
Respiratory Insufficiency
Respiration Disorders
Respiratory Tract Diseases