In our institution ICP was monitored in patients with GCS < or = 8 and abnormal CT scan: 362 severely head injured and 180 subarachnoid hemorrhage. Mean duration of monitoring was 103.6 hours (SD 74.96). Among 542 patients, 440 showed at least one episode of ICP above the threshold of 20 mm Hg. Among 362 head injured patients only 71 (19.3%) had an ICP lower than 20 mm Hg. In the remaining 289 (81.7%) at least one episode > or = 20 mm Hg was measured. In 13 cases (2.2%) a ventricular infection has been diagnosed. In 1 case an intraparenchimal hemorrhage related to the presence of the catheter was detected. Elevated risk of HICP and low incidence of complications have been shown in this series.