Feasibility of Upright Bed Position in ARDS Patients
| Status: | Completed |
|---|---|
| Conditions: | Hospital, Hospital, Pulmonary |
| Therapuetic Areas: | Pulmonary / Respiratory Diseases, Other |
| Healthy: | No |
| Age Range: | 18 - Any |
| Updated: | 8/11/2018 |
| Start Date: | April 2013 |
| End Date: | June 2015 |
Lower lobe atelectasis of the lung is common in Acute Respiratory Distress Syndrome (ARDS)
and has the potential to adversely impact lung compliance and intra-pulmonary shunt. The
cephalic shift of the diaphragm and dorsal atelectasis associated with the commonly used
supine position might also contribute to this shunt. Reports indicate that obese patients may
be more likely to develop dorsal atelectasis than non-obese patients.
The investigators hypothesized that opening the body position angle at the waist from a
typical head of bed at 30 degrees to one similar to a more upright reverse trendelenburg
position, would alter the position of the diaphragm downward, allowing for improved aeration
of lung bases. Thus, the investigators examined the upright body positioning in mechanically
ventilated patients with ARDS primarily by evaluating for effects on oxyhemoglobin saturation
(O2sat), Tidal Volume (TV) and Respiratory Rate (RR).
and has the potential to adversely impact lung compliance and intra-pulmonary shunt. The
cephalic shift of the diaphragm and dorsal atelectasis associated with the commonly used
supine position might also contribute to this shunt. Reports indicate that obese patients may
be more likely to develop dorsal atelectasis than non-obese patients.
The investigators hypothesized that opening the body position angle at the waist from a
typical head of bed at 30 degrees to one similar to a more upright reverse trendelenburg
position, would alter the position of the diaphragm downward, allowing for improved aeration
of lung bases. Thus, the investigators examined the upright body positioning in mechanically
ventilated patients with ARDS primarily by evaluating for effects on oxyhemoglobin saturation
(O2sat), Tidal Volume (TV) and Respiratory Rate (RR).
Acute respiratory failure and acute respiratory distress syndrome is a life-threatening
occurrence. The annual incidence of ARDS is 141,500 patients, with 59,000 deaths, and a cost
of 1,642,000 hospital days/year. Within this population, special care needs of obese patients
are becoming a clinically important entity within the Intensive Care Unit (ICU). ICU
literature on body positioning for obese mechanically ventilated patients is limited.
Currently, intubated obese patients are placed in the supine position with the head of bed
elevated at 30 degrees. The 30 degree head up position has been adopted for all patients as a
reflection of the Ventilator Associated Pneumonia prevention literature. In all critically
ill patients on mechanical ventilation, a cephalic shift of the diaphragm along with dorsal
atelectasis of the lung occurs. In obese patients this alteration may be associated with
greater degree of impairment in lung compliance and gas exchange as compared to non-obese
ventilated patients. It is possible that current ICU body positioning recommendations for
obese mechanically ventilated patients may be detrimental due to the obese abdominal
compartment hampering normal diaphragm function and position.
In supine, intubated, mechanically ventilated patients it has long been noted that lower lung
lobes become atelectatic soon after intubation due to several factors such as accumulation of
fluids, air closure, and a cephalic shift of the diaphragm. Obese patients develop more
atelectasis during anesthesia than non-obese patients. There have been attempts to correct
this iatrogenic complication in critically ill patients such as placement of patients in the
prone position. Prone positioning does resolve the dorsal atelectasis and shows improvement
in hypoxia. However there is no mortality benefit with prone positioning. Also, continuous
lateral rotational patient positioning on mechanical ventilation has shown similar effects7.
Specific literature with regards to obese patients and their unique susceptibility towards
this phenomenon is limited.
As BMI increases there is an associated reduction of lung volumes, expiatory reserve volume,
and functional reserve capacity. It is also known that in the reverse trendelenburg position,
there is a gravitational pull allowing abdominal contents to descent toward the pelvis. This
position of the abdominal contents allows for a more functional diaphragm position. One
observational study 10 conducted a 12 hour intervention which examined upright position with
patients' body in a straight line at 40-45 degrees (i.e., reverse trendelenburg-no bend at
the waist). This study demonstrated a significant increase in the PaO2/FiO2 ratio (ie,
oxygenation) during upright position.
occurrence. The annual incidence of ARDS is 141,500 patients, with 59,000 deaths, and a cost
of 1,642,000 hospital days/year. Within this population, special care needs of obese patients
are becoming a clinically important entity within the Intensive Care Unit (ICU). ICU
literature on body positioning for obese mechanically ventilated patients is limited.
Currently, intubated obese patients are placed in the supine position with the head of bed
elevated at 30 degrees. The 30 degree head up position has been adopted for all patients as a
reflection of the Ventilator Associated Pneumonia prevention literature. In all critically
ill patients on mechanical ventilation, a cephalic shift of the diaphragm along with dorsal
atelectasis of the lung occurs. In obese patients this alteration may be associated with
greater degree of impairment in lung compliance and gas exchange as compared to non-obese
ventilated patients. It is possible that current ICU body positioning recommendations for
obese mechanically ventilated patients may be detrimental due to the obese abdominal
compartment hampering normal diaphragm function and position.
In supine, intubated, mechanically ventilated patients it has long been noted that lower lung
lobes become atelectatic soon after intubation due to several factors such as accumulation of
fluids, air closure, and a cephalic shift of the diaphragm. Obese patients develop more
atelectasis during anesthesia than non-obese patients. There have been attempts to correct
this iatrogenic complication in critically ill patients such as placement of patients in the
prone position. Prone positioning does resolve the dorsal atelectasis and shows improvement
in hypoxia. However there is no mortality benefit with prone positioning. Also, continuous
lateral rotational patient positioning on mechanical ventilation has shown similar effects7.
Specific literature with regards to obese patients and their unique susceptibility towards
this phenomenon is limited.
As BMI increases there is an associated reduction of lung volumes, expiatory reserve volume,
and functional reserve capacity. It is also known that in the reverse trendelenburg position,
there is a gravitational pull allowing abdominal contents to descent toward the pelvis. This
position of the abdominal contents allows for a more functional diaphragm position. One
observational study 10 conducted a 12 hour intervention which examined upright position with
patients' body in a straight line at 40-45 degrees (i.e., reverse trendelenburg-no bend at
the waist). This study demonstrated a significant increase in the PaO2/FiO2 ratio (ie,
oxygenation) during upright position.
Inclusion Criteria:
- Mechanically ventilated
- Chest radiograph must show parenchymal lung infiltrates.
- Acute Lung Injury
- Study shall occur 96 hours after consent has been obtained
Exclusion Criteria:
- Hemodynamic instability and/or use of a vasopressor within the last 6 hours prior to
enrollment.
- Pregnant patients.
We found this trial at
1
site
Click here to add this to my saved trials
