Effect of backrest position on intracranial pressure and cerebral perfusion pressure in individuals with brain injury: a systematic review.

Head elevation is a conventional nursing procedure for brain-injured individuals with intracranial hypertension; it is performed with the intent of reducing intracranial pressure (ICP) by means of a noninvasive physical intervention. However, in certain circumstances, head elevation puts the brain-injured individual at risk for secondary cerebral injury because of impaired arterial blood pressure and compromised cerebral perfusion pressure (CPP). A systematic literature search was conducted to evaluate existing evidence regarding the effect of changing the backrest position on ICP and CPP in brain-injured individuals. Eleven articles were retrieved. In nine articles it was concluded that ICP significantly decreased at 30 degrees of head elevation compared with a flat position. Five of the nine articles showed no statistical significance in the magnitude of change in CPP from a flat position to 30 degrees of head elevation. Major limitations in the 11 articles were small sample sizes and unclear study protocols, which may have caused a failure to detect the effect of head elevation. In clinical practice, intensive care unit staff members need to cautiously perform head elevation with a thorough understanding of its physiologic effect and potential hazard. Future research should investigate the effects of therapeutic positions on different neurological and neurosurgical populations and explore the combination of head elevation and lateral side-lying positions.