According to research published online in the American Journal of Critical Care, level of backrest elevation is not associated with changes in tissue integrity among critically ill patients receiving mechanical ventilation.

Mary Jo Grap, R.N., Ph.D., from Virginia Commonwealth University in Richmond, and colleagues describe the effect of backrest elevation on the integrity of sacral tissue in 84 critically ill adults receiving mechanical ventilation for at least 24 hours.

Patients from 3 critical care units (surgical trauma, medical respiratory, and neuroscience) who were expected to have mechanical ventilation for at least 24 hours were intubated and mechanical ventilation was started.

Participants were enrolled in the study within 24 hours of intubation. Backrest elevation was continuously measured by using the mechanical system– based accelerometers. The integrity of sacral tissue was evaluated by using high-frequency sonography.

The researchers observed no significant difference among the proportions of time spent at <20° (P values = 0.57 the first 24 hours, 0.17 the first 48 hours, and 0.81 the first 72 hours), 20 to 30° (P values = 0.25 the first 24 hours, 0.08 the first 48 hours, and 0.25 the first 72 hours), or >30°  (P values = 0.62 the first 24 hours, 0.28 the first 48 hours, and 0.68 the first 72 hours) among patients with no injury, no change in injury, improvement in injury, or injury that worsened.

Level of backrest elevation is not associated with changes in tissue integrity. Body positioning in critically ill patients receiving mechanical ventilation may not be as important or as effective as once thought.