Purpose: This study was done to investigate the effects of backrest elevation of 0 degree and 30 degrees that minimize the risk of increasing ICP when CVP is measured. Methods: Subjects were sixty-four patients who stayed in the neurosurgical intensive care unit after brain surgery at two university-based hospitals. CVP, blood pressure, heart rate and ICP were measured along with position changes in order of backrest position with primary 30 degrees backrest position, 0 degree backrest position and secondary 30 degrees backrest position. For data analysis, one-group, repeated-measures analysis of variance design was used in SAS program. Results: Backrest elevations from 0 degree to 30 degrees did not alter the CVP without increasing the ICP. Therefore, 30 degrees backrest position is a preventive position without increasing ICP. Conclusion: 30 degrees backrest position might be appropriate for brain injury patients when CVP is measured.