Persons with increased intracranial pressure (ICP) from all causes are subject to periods of markedly increased pressure. Research since the initial clinical studies in the early 1960s has focused primarily on characteristics of ICP variations in specific pathologies and on mechanisms basic to increases in ICP rather than on the relationship between basic patient-care activities, such as moving the patient in bed, and variations in ICP. Therefore, nine patients with pressure-controlled ventriculostomy drainage systems were observed continuously for up to 24 hours to determine what, if any, patient-nurse activities were associated with transient or sustained increased ICP. Frequencies of ventricular fluid drainage (VFD) during activity and nonactivity were compared to predicted frequencies. One patient had no VFD: eight patients had greater than predicted incidence of VFD associated with activity and less than predicted incidence associated with nonactivity. The difference between predicted and actual incidence of VFD was statistically significant (p<.001) for all eight patients. Although each patient displayed individual patterns of specific activity associated with VFD, turning in bed and conversation about the patient's condition were consistent among the sample. Coughing, chewing, use of bedpan, and restless movements were consistently associated with VFD in patients.