Mechanical Ventilation Complication
Conditions
Keywords
Ventilation, Tracheotomy, Difficult weaning, Spontaneous Breathing Test, Esophageal pressure, Work of breathing, Esophageal pressure time-product, Difficult weaning from mechanical ventilation, Ventilation weaning
Brief summary
Datas are lacking concerning weaning from mechanical ventilation for tracheostomized patients. In particular, the effect of different modalities of spontaneous breathing trials on respiratory effort has not been extensively described. This crossover physiology study will include 18 tracheostomized patients ventilated for more than 72 hours. The objective of this study is to compare the effect of three different modalities of SBTs on respiratory effort in tracheostomized patients. The modalities tested are : Pressure Support Ventilation (PSV level 5 cmH2O, PEEP 5 cmH2O), T-piece test and high-flow Oxygen. Each modality is applied in a randomized order, during 30 minutes. During every modality tested, esophageal and gastric pressure, expired CO2, and comfort will be monitored, in addition to standard monitoring. Based on esophageal pressure monitoring, patient's respiratory efforts can be calculated either by esophageal pressure-time product and work of breathing. Pressure generated by inspiratory muscles will also be assessed.
Interventions
PROCEDUREModality 1
Pressure support ventilation (PSV) modality
PROCEDUREModality 2
T-Piece modality
PROCEDUREModality 3
High-flow oxygen
Sponsors
Piquilloud Imboden Lise
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE
Intervention model description
Three different spontaneous breathing trials modalities will be tested in each patient in a randomized order. Washout periods will be performed between the tested modalities.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients for whom a tracheostomy is planned * Patients on invasive ventilation for \>72 hours
Exclusion criteria
* Tracheostomy for upper airway obstruction or other disease * Patients tracheostomized before current hospitalization * Patients with Glasgow Coma Scale (GCS) \< 8/10 after cardiac arrest * Patients with GCS \< 8/10 because of primary central neurologic disease * Patients for whom therapeutic limitations have already been decided * Patients for whom weaning from ventilation is not an objective * Patients suffering from myasthenia gravis * Patients with cardiac assistance device * Patients with medullary lesion proximal to C5 * Patients for whom nasogastric tube insertion is contraindicated
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Evolution of pressure-time product of esophageal pressure | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Quantification of inspiratory effort of the patient |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Evolution of esophageal pressure drop | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Maximum variation of esophageal pressure during respiratory cycles |
| Evolution of inspiratory muscle pressure (Pmus) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Pressure generated by patients' respiratory muscles |
| Evolution of transdiaphragmatic pressure (Ptransdiaph) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Difference between gastric and esophageal pressure. Reflect of pressure generated by diaphragm during inspiration |
| Evolution of tidal volume (VT) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | — |
| Evolution of respiratory rate (RR) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | — |
| Evolution of inspiratory airway flow | Recorded every 5 minutes during each sequence and washout period, 180 minutes | — |
| Evolution of ratio of inspiratory time over total duration of a breathing cycle (ti/ttot) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | — |
| Evolution of Rapid Shallow Breathing Index (RSBI) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | RR/VT - predictor during ventilation weaning of intolerance of SBT |
| Evolution of respiratory system compliance (Crs) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Capacity of total respiratory system to gain volume for a given pressure |
| Evolution of lungs compliance (CL) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Capacity of lungs to gain volume for a given pressure |
| Evolution of chest wall compliance (Ccw) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Capacity of lungs to gain volume for a given pressure |
| Evolution of transpulmonary pressure (Ptranspulm) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Alveolar pressure minus pleural pressure |
| Evolution of ratio of total dead space volume over tidal volume | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Calculated by means of expired CO2 and arterial blood gas CO2 |
| Evolution of work of breathing (WOB) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Total area of a Campbell diagram for esophageal pressure and volume during one respiratory cycle |
| Evolution of total Positive End-Expiratory Pressure (PEEPtot) | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Airway pressure during end-expiratory ventilator occlusion |
| Evolution of heart rate | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Standard monitoring |
| Evolution of blood pressure | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Standard monitoring |
| Evolution of Plateau pressure (Pplat) | Recorded at minute 1 and minute 30 of each three spontaneous Breathing Trial, 90 minutes | Airway pressure during end-inspiratory ventilator occlusion (corresponds to alveolar pressure) |
| Evolution of intrinsic Positive End-Expiratory Pressure (PEEPi) | Recorded at minute 1 and minute 30 of each three spontaneous Breathing Trial, 90 minutes | PEEPi minus PEEP set on ventilator |
| Pulmonary strain | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Measured as the ratio of tidal volume over functionnal residual capacity (FRV) |
| Evolution of Diaphragmatic excursion (DE) | Recorded at minute 1 and minute 30 of each three spontaneous Breathing Trial, 90 minutes | Ultrasound measurement of diaphragm movement during inspiration |
| Evolution of Diaphragmatic thickening fraction (DTF) | Recorded at minute 1 and minute 30 of each three spontaneous Breathing Trial, 90 minutes | Ultrasound measurement of diaphragm thickening during inspiration |
| Evolution of hematocrits | Recorded at minute 30 of each three spontaneous Breathing Trial, 90 minutes | Mesured by arterial blood |
| Evolution of Richmond Agitation/Sedation scale (RASS) score | Recorded at minute 1 and minute 30 of each three spontaneous Breathing Trial, 90 minutes | Used in ICU to monitor neurologic changes in patients. Scale from -5 (unarousable) to +4 (combative). 0 is a calm and responsive patient. |
| Evolution of Borg dyspnea scale score | Recorded at minute 1 and minute 30 of each three spontaneous Breathing Trial, 90 minutes | Numeric scale to quantify dyspnea from 0 to 10. 0 mean patient does not feel that breathing is difficult and 10 is a maximal dyspnea. Measured twice during each Spontaneous Breathing Trial |
| Evolution of Multidimensionnal dyspnea scale (MDP) score | Recorded at minute 30 of each three spontaneous Breathing Trial, 90 minutes | Score to quantify comfort, dyspnea and assess respiratory effort as perceived by patient. This scale contains multiple items, divided in two dimensions : sensory and affective. Sensory dimension contains : intensity on a scale of 0 to 10 of five sensory qualities (physical breathing effort, air hunger, tightness, mental breathing effort, hyperpnoea) Affective dimension contains : a breathing discomfort scale (scale of 0 to 10) Measured once during each Spontaneous Breathing Trial |
| Evolution of total dead space volume | Recorded every 5 minutes during each sequence and washout period, 180 minutes | Calculated by means of expired CO2 |
Countries
Switzerland
Contacts
Primary ContactLise Piquilloud Imboden, MER&PD
Backup ContactDavy Cabrio
Outcome results
None listed