Invasive monitoring of intracranial pressure (ICP) plays an important role in managing many neurosurgical patients. While there are several techniques available to monitor ICP, the ventricular catheter is most commonly used and the most accurate. ICP monitoring poses potential risks to the patient. The most common and one of the most devastating complications is infection. This research study examined the rate of bacterial ventriculitis in relation to duration of ventricular catheter insertion as well as other factors which may contribute to ventriculitis. Data were collected prospectively on 78 patients with a ventriculostomy who were 14 years of age or older and admitted to the neuroscience intensive care unit. Patients were followed from the time of ventricular catheter placement to two weeks after the catheter was removed or until the patient was discharged from the hospital. A significantly higher ventriculitis rate was found in patients with a mean catheter duration of 11 days or longer (p = .004). In the group that developed ventriculitis there was a significant rise (means = 6.03592, p = .014) in the cerebrospinal fluid (CSF) lactate prior to the onset of ventriculitis. Neuroscience nurses should be aware of the factors which may increase the rate of ventriculitis, such as duration of catheter placement and factors which may indicate impending infection such as a rise in the CSF lactate. Future studies should compare various methods of ventriculostomy site care for efficacy of infection prevention, cost and caregiver time.