Correlation Between Intracranial Pressure and Optic Nerve Sheath Diameter Measured With CLOSED Bundle in Patients With Acute Brain Injury: Multicenter Observational Study

The design of the present study will be a multicenter prospective observational protocol. Approximately 100 patients will be recruited over the 24-month period with Acute Brain Injury (trauma brain injury, intracerebral hemorrhage, subarachnoid hemorrhage, ischemic stroke), who in their acute phase of intensive care unit require placement of a catheter capable of monitoring intracranial pressure (intra parenchymal catheter or external ventricular shunt). In addition to all the intensive care provided by the most recent guidelines, patients will undergo measurement of optic nerve sheath diameter through ultrasonography. At least, three measurements will be performed within the first 3 hours after admission, within the first 24-48 hours, and at each invasive intracranial pressure value greater than 18 cmH2O. Those patients with intracranial pressure values greater than 35 mmHg. At the first intracranial pressure measurement, patients with eyeball disease or trauma will be excluded. Measurements will be performed following the CLOSED bundle.

Analysis of the results will include correlation between the invasive pressure values and the mean value of optic nerve sheath diameter measurements in the two projections (sagittal and transverse). In addition, the correlation of the absolute value of invasive pressure detected with the ratio of the optic nerve sheath diameter measurement to the eyeball diameter measured always ultrasound will be sought.