Invasive Versus Non-Invasive Intracranial Pressure-Guided Management in Neurosurgical Patients

Raised intracranial pressure (ICP) is one of the most feared complications in neurosurgical practice, capable of critically reducing cerebral perfusion and leading to secondary brain injury. While invasive ICP monitoring through an external ventricular drain (EVD) remains the gold standard for real-time decision-making and therapeutic cerebrospinal fluid (CSF) drainage, it requires surgical expertise and carries risks such as hemorrhage and infection. Non-invasive alternatives, particularly optic nerve sheath diameter (ONSD) ultrasonography, have emerged as rapid, bedside-based, and repeatable tools for estimating ICP, especially in resource-limited settings. This prospective, comparative cohort study evaluates the clinical and neurological outcomes of neurosurgical patients managed with either invasive ICP monitoring or non-invasive ONSD monitoring. The study enrolled 40 adult neurosurgical patients (aged 18 and above) presenting with conditions such as traumatic brain injury, subarachnoid hemorrhage, intracranial hemorrhage, and hydrocephalus at Kathmandu Medical College Teaching Hospital. Based on the clinical decision of the attending neurosurgical team, patients were assigned to one of two management arms: Group A (Invasive): Received standard aseptic placement of an EVD or cisternal drain connected to a pressure transducer. ICP was monitored continuously, and therapeutic CSF drainage was utilized as an active, tier-1 ICP-control measure when thresholds were exceeded. Group B (Non-Invasive): Received serial bedside ONSD measurements using a high-frequency (7.5 MHz) linear ultrasound probe. Measurements were taken at strict intervals (hourly for 24 hours, four-hourly up to 72 hours, and twice daily up to day 5) or upon signs of neurological deterioration to guide tiered medical management, such as hyperosmolar therapy and controlled hypocapnia. DOCX Clinical parameters, including Glasgow Coma Scale (GCS) scores, mean arterial pressure (MAP), and the use of osmotic agents, were recorded concurrently. The primary objective of the study is to evaluate the trajectory of neurological recovery between the two monitoring modalities by tracking daily GCS trends. Secondary objectives include comparing functional outcomes at hospital discharge using the Glasgow Outcome Scale (GOS) and modified Rankin Scale (mRS), assessing the total hospital length of stay, and recording the incidence of procedure-related complications and secondary neurological deterioration.