Elevated intracranial pressure (ICP) is a life-threatening condition that requires meticulous management, particularly during anesthesia. When ICP rises, the risk of brain ischemia and herniation increases, requiring a tailored anesthetic approach to optimize outcomes while minimizing additional pressure elevation.
Intracranial pressure is determined by the volumes of brain tissue, cerebrospinal fluid (CSF), and blood within the skull. Under normal conditions, ICP ranges from approximately 7 to 15 mmHg in adults. Causes of elevated ICP include traumatic brain injury, tumors, hydrocephalus, intracranial hemorrhage, and infections like meningitis. Symptoms may include headache, vomiting, altered mental status, and signs of brainstem compression such as pupillary abnormalities 1.
Anesthesia management for patients with elevated intracranial pressure (ICP) requires careful preoperative, intraoperative, and postoperative considerations. A thorough preoperative assessment, including imaging studies like CT or MRI scans, is essential to identify the cause and severity of ICP elevation 2,3, with stabilization measures aimed at controlling ICP, optimizing oxygenation, and ensuring hemodynamic stability. Continuous monitoring of ICP, cerebral perfusion pressure (CPP), and other vital parameters during anesthesia is critical, often utilizing devices such as intraparenchymal pressure monitors or external ventricular drains, along with end-tidal CO₂ monitoring to maintain appropriate carbon dioxide levels and influence cerebral blood flow 4.
Smooth induction of anesthesia can mitigate ICP spikes, with agents like propofol or thiopental being preferred for their ability to reduce cerebral metabolic rate and ICP, while avoiding ketamine due to its potential to increase cerebral blood flow. Ventilation management, including controlling the partial pressure of CO₂ (PaCO₂) in order to influence ICP, must avoid excessive hyperventilation to prevent ischemia 5.
Intraoperative maintenance typically involves carefully titrated volatile anesthetics like isoflurane or sevoflurane; neuromuscular blockade with agents like rocuronium to prevent ICP-elevating actions such as coughing or straining; and fluid management emphasizing isotonic solutions while avoiding fluid overload and hypotonic fluids to prevent cerebral edema.
Postoperatively, smooth emergence from anesthesia is critical to prevent coughing, agitation, or pain-induced exacerbations of elevated intracranial pressure, necessitating adequate analgesia and sedation, with early imaging often warranted to evaluate for complications or changes in ICP 4,6,7.
Clinical management strategies often include elevating the head of the bed to 30 degrees to facilitate venous drainage, and avoiding neck flexion or rotation, which can impede venous outflow 8. In addition, mannitol or hypertonic saline can be administered to reduce ICP if necessary. Steroids may be used for conditions like brain tumors but are contraindicated in traumatic brain injury 9.
Anesthesia for patients with elevated intracranial pressure requires a comprehensive understanding of cerebral physiology and meticulous planning to prevent secondary brain injury. By carefully selecting anesthetic agents, monitoring parameters, and using specific strategies to control ICP, anesthesiologists can optimize outcomes and protect the delicate balance of cerebral perfusion and pressure.
References
1. Increased Intracranial Pressure. Cleveland Clinic https://my.clevelandclinic.org/health/diseases/increased-intracranial-pressure-icp.
2. Kim, D. Y. et al. Comparison of ultrasonography and computed tomography for measuring optic nerve sheath diameter for the detection of elevated intracranial pressure. Clinical Neurology and Neurosurgery 204, 106609 (2021). DOI: 10.1016/j.clineuro.2021.106609
3. Barkatullah, A. F., Leishangthem, L. & Moss, H. E. MRI findings as markers of idiopathic intracranial hypertension. Curr Opin Neurol 34, 75–83 (2021). DOI: 10.1097/WCO.0000000000000885
4. Munakomi, S. & Das, J. M. Intracranial Pressure Monitoring. in StatPearls (StatPearls Publishing, Treasure Island (FL), 2024).
5. Airway management in the patient with elevated ICP for emergency medicine and critical care – UpToDate. https://www.uptodate.com/contents/airway-management-in-the-patient-with-elevated-icp-for-emergency-medicine-and-critical-care.
6. Pattinson, K., Wynne-Jones, G. & Imray, C. H. Monitoring intracranial pressure, perfusion and metabolism. Continuing Education in Anaesthesia Critical Care & Pain 5, 130–133 (2005). DOI: 10.1093/bjaceaccp/mki035
7. Pinto, V. L., Tadi, P. & Adeyinka, A. Increased Intracranial Pressure. in StatPearls (StatPearls Publishing, Treasure Island (FL), 2024).
8. Sattur, M. G., Patel, S. J., Helke, K. L., Donohoe, M. & Spiotta, A. M. Head Elevation, Cerebral Venous System, and Intracranial Pressure: Review and Hypothesis. Stroke: Vascular and Interventional Neurology 3, e000522 (2023). DOI: 10.1161/svin.122.000522
9. Choudhury, A. et al. Efficacy of Intravenous 20% Mannitol vs 3% Hypertonic Saline in Reducing Intracranial Pressure in Nontraumatic Brain Injury: A Systematic Review and Meta-analysis. Indian J Crit Care Med 28, 686–695 (2024). DOI: 10.5005/jp-journals-10071-24746
