Reverse Trendelenburg Position Versus Semi-recumbent Position in Obese Critically Ill Patients

Effect of Reverse Trendelenburg Position Versus Semi-recumbent Position on Ventilation and Oxygenation Parameters in Obese Critically Ill Patients: Randomized Controlled Trial

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

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.

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.

Obese critically ill patients who are positioned in semi-recumbent position which is the routine ICU position

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.

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 (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.

Inclusion Criteria: body mass index ≥ 30 Mechanically ventilated Exclusion Criteria: Trauma Shock Acute respiratory distress syndrome

Researchers are waiting to get approval from research committee to make individual participant data (IPD) available to other researchers