Neuromonitoring: an overview

Acute brain injury is a leading cause of ICU admission and long-term disability. Clinical neurological examination is frequently limited by sedation and mechanical ventilation, making objective physiological monitoring essential. While intracranial pressure remains the cornerstone of neurocritical care, pressure alone provides an incomplete picture of the complex pathophysiology underlying secondary brain injury, and contemporary practice has progressively moved toward multimodal neuromonitoring strategies. This narrative review summarizes the most widely used neuromonitoring techniques beyond clinical examination and neuroimaging, describing their physiological rationale, available evidence, clinical indications, and practical limitations. Invasive ICP monitoring, non-invasive estimation methods, cerebral perfusion and autoregulatory assessment, oxygenation-based monitors, cerebral microdialysis, and neurophysiological techniques are systematically addressed. Randomized evidence supporting these modalities remains limited, and most recommendations derive from observational studies and expert consensus. The integration of complementary monitors within individualized, goal-directed frameworks represents the current standard in advanced neurocritical care practice.