The external ventricular drain (EVD) is a temporary system, which with the help of gravity enables the drainage of cerebrospinal fluid (CSF) from the ventricle to the outside closed system. Catheter placement (ventriculostomy) is performed through Trepanation opening, at the Kocher point, usually in the third ventricle. When the drainage is temporary, we call it external ventricular drainage (EVD), and if it is permanent, we are talking about placing a shunt. Ventricular shunts are called according to the place where the drainage catheter ends, so for example the shunt can be peritoneal, because it ends in the peritoneal cavity. The primary indication for EVD placement is therapeutic, that is, drainage of cerebrospinal fluid or blood, with the aim of lowering intracranial pressure. Raised intracranial pressure is often associated with three factors: brain edema, intracranial hypertension and hydrocephalus. Acute obstructive hydrocephalus is a frequent complication after aneurysm of subarachnoid hemorrhage, where there is a sudden increase in ICP, which can lead to rapid loss of consciousness and even death of the patient. Elevated ICP can be medically controlled by analgosedation of the patient and osmotic diuretics, however, such treatment is often not enough, and it is urgently needed to proceed to neurosurgical treatment, i.e. placement of EVD. After the neurosurgeon place an EVD, the patient is placed to the neurological or neurosurgical intensive care unit treatment, where maintaining and solving the EVD problem becomes a responsibility of nurses. The aim of this work is to make a complete presentation of the subject of EVD, from basic anatomical and physiological postulates about cerebrospinal fluid, its pathophysiology, to describe the complications that arise as a result of cerebrospinal fluid flow obstruction, and show the complexity and seriousness of the work carried out by nurses in neurological intensive care unit. Point out the need for additional education of nurses, in order to be able to ensure safe and quality health care for patients with EVD.