Clinical trial NCT01321398: Transpulmonary Pressure Gradients in High Frequency Oscillation
Official title: Transpulmonary Pressure Gradients in High Frequency Oscillation Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Acute Lung Injury
Keywords: High Frequency Oscillation
Oscillation
HFO
Transpulmonary pressure
Lead sponsor: University of British Columbia
Sponsor class: OTHER
First posted: 2011-03-23
Enrollment: 7
Sex: ALL
Minimum age (years): 19
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Critically Ill

Brief summary: Patients with severe lung conditions occasionally require support with a special ventilator (breathing machine) called the High Frequency Oscillator (HFO). Effective ventilation requires that the pressure generated by the ventilator be as high as possible but not too high as this can damage the lungs. In patients on HFO, there is not a well defined way to measure this pressure. We will insert a small probe into the esophagus of patients on HFO to see if this is an accurate way to measure lung pressures for these patients. A better understanding of these pressures could lead to improved patient care.

Detailed description: Trials have found that the use of lower tidal volumes (6 ml/kg) during conventional mechanical ventilation decreases morbidity and mortality. Compared to conventional ventilation, high frequency oscillation (HFO) is able to provide much smaller tidal volumes (1.1 - 2.5 ml/kg) and thus theoretically may provide additional lung protection. At this time, while trials of HFO in adults have been inconclusive, the use of HFO for the management of ALI/ARDS has become widespread

Patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) are critically ill and have a high mortality associated with their illness (approximately 50%). Currently, esophageal pressure monitors are used to optimize inflation pressures and improve oxygenation in conventional mechanical ventilation in patients with ALI/ARDS. With this in mind, the purpose of this study is twofold: (1) demonstrate that esophageal pressure monitors can easily be inserted in patients undergoing HFO and (2) report the transpulmonary pressures in these patients.

Eligibility criteria: Inclusion Criteria:

* 19 years of age or older
* Receiving HFO
* Informed Consent Obtained

Exclusion Criteria:

* Esophageal lesions or esophageal surgery within the last 6 months
* Morbid obesity - defined as a Body Mass Index (BMI) \> 40
* Unstable cervical spine injury or cervical spinal cord injury

Primary outcomes:
measure: To demonstrate the proof of concept that esophageal pressures can easily be obtained in patients undergoing HFO.
timeFrame: 60 minutes
Secondary outcomes:
measure: To determine the transpulmonary pressure gradient in critically ill patients receiving HFO
timeFrame: 60 minutes
Other outcomes:
Locations:
city: Vancouver
country: Canada
facility: Vancouver General Hospital
state: British Columbia
Study officials:
affiliation: Universtiy of British Columbia
name: William R Henderson, FRCPC
role: PRINCIPAL_INVESTIGATOR
References: