Acute Lung Injury (ALI), Acute Respiratory Distress Syndrome
Conditions
Brief summary
The purpose of this study is to examine changes in ventilation and airway pressures during conventional bronchoscopy of intubated patients.
Detailed description
Mechanically ventilated patients often need bronchoscopy as a diagnostic procedure or for visually directed elimination of secretions. Partial endotracheal tube occlusion by the bronchoscope increases airflow resistance. Inhibition of inspiratory flow may be compensated for by augmented inspiratory pressure. Reduced expiratory flow however, cannot be compensated for by most ventilators and could lead to higher airway - and intrathoracic pressures that are not detected by pressure transducers in the ventilator tubing. In this study we compare changes in ventilation, airway pressures, ventilator pressures and blood gases during bronchoscopy of intubated patients in both volume controlled and pressure controlled ventilation. Our hypothesis are that 1) increased resistance in the tube during bronchoscopy leads to high intrabronchial airway pressures when the ventilator is in volume controlled mode, and 2) when the ventilator is in pressure controlled mode, increased resistance in the tube during bronchoscopy leads to reduced Tidal Volume and moderately increased paCO2.
Interventions
OTHERBronchoscopy
Airway pressures, ventilation changes and blood gas changes are recorded in a group of intubated patients on mechanical ventilation before and after bronchoscope insertion. The registration is done immediately before a therapeutic/diagnostic bronchoscopy requested by a staff physician not involved n the study.
Sponsors
Oslo University Hospital
Study design
Observational model
CASE_ONLY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* ARDS/ALI patients on mechanical ventilation * endotracheal tube size 7-9mm * age \> 18 years * therapeutic or diagnostic bronchoscopy requested by staff physician
Exclusion criteria
* SpO2 \< 90% * unstable BP * pneumothorax * acute cardiovascular disease * cerebrovascular or other condition that requires stable BP and saturation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in ventilation, airway pressures and blood gases after bronchoscope insertion. | 2 minutes after bronchoscope insertion/ mode change | paO2, paCO2 (kPa), airway and ventilator pressures (cmH2O) |
Countries
Norway
Outcome results
None listed