Examination of sacral tissue oxygen saturation among immobile patients

AIMS AND OBJECTIVES To explore the effect of immobility on sacral tissue oxygen saturation in patients lying on a supporting surface in supine position. BACKGROUND Guidelines in regard to preventing pressure ulcers recommend that patients lying on a standard bed should change their positions every 2 hr and that patients on a supporting surface should change their positions every 4 hr. But there is no strong evidence that justifies this practice. DESIGN Quasi-experimental. METHODS Data for the research were collected over the period October 2014-March 2015 at Anesthesiology and Reanimation and Neurosurgery Clinic Intensive Care Units. A total of 46 patients matching the research criteria were left in the supine position for 4 hr without having a position change, during which time sacral tissue oxygen saturation was measured every hour on the hour. Sacral tissue oxygen saturation was measured with the InSpectra Tissue Oxygenation Monitor. RESULTS Mean sacral tissue oxygen saturation was 73.4% at baseline and was then measured as 74.9% at the first hour, 72.3% at the second hour, 71.9% at the third hour and 71.9% at the fourth hour. The changes observed between measuring times were not found to be statistically significant (p = .09). CONCLUSIONS No statistically significant differences were found between sacral tissue oxygen saturation values recorded over a period of 4 hr in immobile patients lying on a supporting surface in the supine position. However, it was observed that sacral tissue oxygen saturation values did not change significantly depending upon the type of supporting surface that was being used. RELEVANCE TO CLINICAL PRACTICE The study outcome supports changing the position of a patient lying on a supporting surface every 4 hr and provides evidence that justifies the recommendation made in the guidelines.