The Effects of Vertical Position on Gas Exchange in Patients With Respiratory Failure
The purpose of this study is to investigate how changing from a supine to upright position affects gas exchange for patients with hypoxemic respiratory failure.
The research question is: will oxygen saturation and/or partial pressure of oxygen in the blood change when a patient with hypoxemic respiratory failure moves from a supine to upright position?
|Study Design:||Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||The Effects of Vertical Position on Gas Exchange in Patients With Respiratory Failure|
- PaO2 to FiO2 ratio [ Time Frame: change from baseline to 1 hr ] [ Designated as safety issue: No ]
- Oxygen Saturation [ Time Frame: change from baseline to 1 hr ] [ Designated as safety issue: No ]
- change in blood PCO2 [ Time Frame: change from baseline to 1 hr ] [ Designated as safety issue: No ]
- Change in blood pH [ Time Frame: change from baseline to 1hr ] [ Designated as safety issue: No ]
- Tidal Volume [ Time Frame: change from baseline to 1 hr ] [ Designated as safety issue: No ]
- Vital Signs [ Time Frame: change from baseline to 1hr ] [ Designated as safety issue: No ]
|Study Start Date:||October 2012|
|Estimated Study Completion Date:||October 2014|
|Estimated Primary Completion Date:||October 2014 (Final data collection date for primary outcome measure)|
Our hypothesis is that blood oxygen tension will not decrease and may even increase when a patient with respiratory failure stands up. Supine positioning often causes partial lung collapse, which results in a decreased amount of lung being available for gas exchange. In patients with Acute Respiratory Distress Syndrome (ARDS), tilting the patient up in bed has been shown to increase oxygen tension and improve lung compliance. Positional changes are sometimes used as a "rescue" intervention in patients with severe hypoxemia from ARDS. The investigators hope to conclude that severe hypoxemia should not be viewed as a contraindication to physical therapy, but rather physical therapy may be a potential intervention for patients with marginal gas exchange.
After sedative interruption, physical therapists and nursing staff will assist mechanically ventilated patients in moving to the side of the bed. They will assess the extremity strength using the MRC scale. If lower extremity strength is at least 4/5, the patient will be assisted to assume the upright position. The investigators will monitor the patient continuously and the session will be stopped at any point for
A. Mean arterial pressure <65 B. Heart rate <40, >130 beats/min C. Respiratory rate <5, >40 breaths/ min D. Pulse oximetry <88% E. Marked ventilator dyssynchrony F. Patient distress G. New arrhythmia H. Concern for myocardial ischemia I. Concern for airway device integrity J. Endotracheal tube removal
At this point, the patient's vital signs, pulse oximetry, and measures of lung compliance will be obtained. If an arterial line is in place and there have been ventilator adjustments since the morning arterial blood gas, the investigators will draw an arterial blood gas.
The physical therapists and nursing staff will then help the patient stand up. After one minute, the investigators will record another set of vital signs, pulse oximetry, and measures of lung compliance from the mechanical ventilator. If an arterial line is in place, the investigators will draw another arterial blood gas.
The patient will then be assisted back into bed. One hour later, the investigators will record the patient's vital signs, pulse oximetry, and measures of lung compliance from the mechanical ventilator.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01705119
|Contact: Jared A Greenberg, MDfirstname.lastname@example.org|
|Contact: John P Kress, MDemail@example.com|
|United States, Illinois|
|University of Chicago Medical Center||Recruiting|
|Chicago, Illinois, United States, 60637|
|Contact: Jared A Greenberg, MD 773-702-5798 firstname.lastname@example.org|
|Principal Investigator: John P Kress, MD|
|Sub-Investigator: Jared A Greenberg, MD|
|Sub-Investigator: Bhakti Patel, MD|
|Sub-Investigator: Maggie Davis-Hovda, MD|
|Sub-Investigator: Anne Pohlman|