The Effect of Lateral Position on PaO2, PaCO2, and O2 Saturation in Patients with Ventilator-Induced Pneumonia

In patients under mechanical ventilation, the patient's position is one of the factors affecting the efficiency of respiratory gas exchange. The aim of this study was to compare the level of arterial blood gas pressure and the percentage of arterial oxygen saturation in the supine position with the lateral position in patients with ventilator-associated pneumonia.

In a clinical trial study with a sample size of 50 patients with ischemic stroke under mechanical ventilation admitted to the intensive care unit of Kashani hospital affiliated to Shahrekord University of Medical Sciences, Shahrekord, Iran, in 2019 were selected using convenience sampling method. Oxygen saturation percentage was measured by a pulse oximeter in patients lying on their backs and then, on their sides for two hours; arterial blood pressure and carbon dioxide levels were measured with arterial blood sample by laboratory device, and recorded in the relevant checklist as well.

In both supine and lateral positions, the mean arterial oxygen pressure and the percentage of hemoglobin oxygen saturation were not significantly different (P > 0.050); while the arterial carbon dioxide pressure in the lateral position was significantly lower than the supine position (P = 0.008).

The lateral position has no significant effect on the improvement of arterial blood gases and oxygen saturation in patients with pneumonia due to mechanical ventilation; but has significantly reduce the pressure of carbon dioxide.