protocolSection identificationModule nctId: NCT06293976, orgStudyIdInfo id: 4506, briefTitle: Susceptibility for Entrainment: Role of Ventilator Settings on the Occurrence of Reverse Triggering and Its Physiological Consequences - the SEVeRe Study, acronym: SEVERE, statusModule overallStatus: RECRUITING, startDateStruct date: 2024-03-01, primaryCompletionDateStruct date: 2026-03-01, completionDateStruct date: 2026-03-01, studyFirstPostDateStruct date: 2024-03-05, lastUpdatePostDateStruct date: 2024-03-05, sponsorCollaboratorsModule leadSponsor name: Unity Health Toronto, class: OTHER, descriptionModule briefSummary: Background: Reverse triggering (RT) is a frequent phenomenon observed in sedated patients under a mechanical ventilation mode called assist-control ventilation. RT is when the ventilator would trigger the patient's respiratory effort instead of the correct order of the patient's respiratory effort triggering the ventilator. Reverse triggering can have negative consequences (loss of protective lung ventilation, and causing double breaths - with the ventilator giving two consecutive breaths and not allowing the patient to exhale) but also offer some protective effects (avoid diaphragm disuse atrophy). The balance of its negative vs positive effects depends on its frequency and magnitude of its associated respiratory effort. Respiratory entrainment is the most often referred mechanism involving a change in patient's rate of breathing effort from that of patient's intrinsic rate to the rate of mechanical insufflation. The specific ventilatory settings associated with or responsible for RT remains unknown.Aims: To assess in mechanically ventilated critically ill patients the influence of the set respiratory rate (RR) and tidal volume (Vt) on the presence/development of RT and to describe the pattern of respiratory muscle activity during Reverse Triggering (RT).Methods. 30 adult patients (15 in each group), sedated and under assist-controlled ventilation will be included. Ventilator settings will be modified to modulate the frequency and magnitude of reverse triggering. Initially, with the ventilator on a mode called volume control, which means the ventilator controls the amount of air (tidal volume) and the number of breaths the patients gets every minute (respiratory rate \[RR\]). The tidal volume will be set at the current standard clinical practice setting (6 ml/kg of predicted body weight). The presence of an intrinsic respiratory rate will be assessed with an end-expiratory occlusion maneuver. Next, the number of breaths the ventilator gives per minute (RR) will be changed from 6 breaths less to 6 breaths more, in steps of 2 breaths every minute. The protocol will be repeated again changing the amount of air the patients gets (tidal volume) from 4, 5, 7 and 8 ml/kg. Continuous recordings of airway pressure, flow, esophageal pressure, electrical activity of the diaphragm, main accessory muscles and frontal electroencephalography will be obtained during the protocol and baseline clinical and physiological characteristics and outcomes will be recorded. A validated software will be used to detect RT and measure the intensity and timing of each muscle electrical activity and the magnitude of the inspiratory effort during RT., conditionsModule conditions: Respiration, Artificial, conditions: Reverse Triggering, designModule studyType: INTERVENTIONAL, phases: NA, designInfo allocation: NA, interventionModel: SINGLE_GROUP, primaryPurpose: OTHER, maskingInfo masking: NONE, enrollmentInfo count: 30, type: ESTIMATED, armsInterventionsModule interventions name: Changes in the ventilator respiratory rate and tidal volume, outcomesModule primaryOutcomes measure: The rate of of reverse triggered breaths occurring after each change in the ventilator respiratory rate and tidal volume., primaryOutcomes measure: The magnitude of the effort, measured by the drop in the esophageal pressure in cmH2O, associated with the reverse triggered breaths after each change in the ventilator respiratory rate and tidal volume, eligibilityModule sex: ALL, minimumAge: 18 Years, stdAges: ADULT, stdAges: OLDER_ADULT, contactsLocationsModule locations facility: Unity Health Toronto - St. Michael's Hospital, status: RECRUITING, city: Toronto, state: Ontario, zip: M5B 1T8, country: Canada, contacts name: Audery Kim, role: CONTACT, phone: 416-864-5686, email: audery.kim@unityhealth.to, contacts name: Antenor Rodrigues, role: SUB_INVESTIGATOR, contacts name: Laurent Brochard, role: PRINCIPAL_INVESTIGATOR, geoPoint lat: 43.70011, lon: -79.4163, hasResults: False