VentricuLostomy AssoCiaTed InfeCtions (LACTIC): Focus on CSF Lactate and Sampling Site

Inclusion Criteria: * Age \>18 years * EVD in situ * Admission to the neuro-ICU or neurosurgical step-down unit at Rigshospitalet, Denmark * Diagnosis of acute brain injury categorized as traumatic brain injury, subarachnoid haemorrhage, intracranial haemorrage, intraventricular haemorrhage Exclusion Criteria: * Patient or closest relatives do not understand written and spoken Danish or English * Patients transferred to Rigshospitalet with an EVD * Patients with brain injury due to existing brain infection (e.g., meningitis, intracranial empyema or abscess, encephalitis) * Patients with existing ventriculoperitoneal or ventriculoatrial shunt at the time of admission * Patients with primary or secondary brain cancer * Patients died or in palliative care