Ventilation and Oxygenation, Obese; Positioning, Critically Ill
Conditions
Keywords
Reverse Trendelenburg position, semi-recumbent position, ventilation, oxygenation, obese patients
Brief summary
The aim of this study is to assess the effect of reverse Trendelenburg position versus semi-recumbent position on ventilation and oxygenation parameters of obese critically ill patients
Detailed description
Obese critically ill patients' position significantly impacts on their ventilation and oxygenation status. It is also associated with mechanical ventilation success or failure and may be a main determinant of the obese patients' outcome. Reverse Trendelenburg position is recommended for obese patients but in critical illness with mechanical ventilation little is known about its effect on respiratory therapeutic targets. This trial was conducted in four general intensive care unit of Alexandria Main University hospital in Alexandria, Egypt. One hundred and ten adult mechanically ventilated patients with body mass index ≥ 30 were randomly assigned by a computer program to either reverse Trendelenburg position group (n=55) which is the intervention group or semi-recumbent position group (n=55) which is the routine unit position. Patients were positioned in the study positions 4 times per day. Patients were maintained in the study positions for 2 hours each time. Baseline ventilation and oxygenation parameters were assessed immediately before positioning then it was reassessed every 10 minutes after positioning for 30 minutes.
Interventions
The Reverse Trendelenburg position is a position in which patients' hip and knee are not flexed but the head and chest are elevated at 30° than the abdomen and legs.
The semi-recumbent position is an upright positioning of the head and torso at an angle of 45° while legs are lying on the bed.
Sponsors
Alexandria University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
SINGLE (Caregiver)
Masking description
Computer generated randomization (www.randomizer.org) was used to randomly assign patients to one of both groups. Information of allocation was available to the principal researcher only. Patients were assigned a sequential number that was placed in an opaque, sealed envelope by the researcher. When the patients were scheduled to be positioning, the envelope was opened by the researcher who then performed the positioning. The nurses could not be blinded to the allocation because of the nature of the intervention. However, the outcome assessment of the patients was blinded.
Intervention model description
two-group pre-test and repeated post-test study
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* body mass index ≥ 30 * Mechanically ventilated
Exclusion criteria
* Trauma * Shock * Acute respiratory distress syndrome
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Partial pressure oxygen | 30 minute form positioning time | Partial pressure oxygen (PaO2) in mm Hg is assessed from arterial blood gases sample. |
| Respiratory dynamic compliance | 30 minute form positioning time | Respiratory dynamic compliance (Cdyn) in ml/cm H2O is the change in lung volume per unit change in pressure in the presence of flow. It is calculated through the equation of tidal volume/ (peak inspiratory pressure - positive end expiatory pressure). All the previous equation variables are assessed from the patient's mechanical ventilator data. |
| Respiratory minute volume | 30 minute form positioning time | Respiratory minute volume (VE) in mL/min is the total volume of air that is expired over one minute. It is calculated directly by the mechanical ventilator and presented on patient's mechanical ventilator data. |
| Partial pressure carbon dioxide | 30 minute form positioning time | Partial pressure carbon dioxide (PaCO2) in mm Hg is assessed from arterial blood gases sample. |
| Hypoxemic index | 30 minute form positioning time | Hypoxemic index is the ratio of partial pressure oxygen to fraction inspiratory oxygen (PaO2/FiO2). |
Countries
Egypt
Outcome results
None listed