Written and peer-reviewed by physicians—but use at your own risk. Read our disclaimer.

banner image


Trusted medical answers—in seconds.

Get access to 1,000+ medical articles with instant search
and clinical tools.

Try free for 5 days

Elevated intracranial pressure and brain herniation

Last updated: April 23, 2021

Summarytoggle arrow icon

Intracranial pressure (ICP) is the pressure that exists within the cranium, including its compartments (e.g., the subarachnoid space and the ventricles). ICP varies as the position of the head changes relative to the body and is periodically influenced by normal physiological factors (e.g., cardiac contractions). Adults in the supine position typically have a physiological ICP of ≤ 15 mm Hg; an ICP of ≥ 20 mm Hg indicates pathological intracranial hypertension. ICP may be elevated in a variety of conditions (e.g., intracranial tumors) and can result in a decrease in cerebral perfusion pressure (CPP) and/or herniation of cerebral structures. Symptoms of elevated ICP are generally nonspecific (e.g., impaired consciousness, headache, vomiting); however, more specific symptoms may be present depending on the affected structures (e.g., Cushing triad if the brainstem is compressed). Findings from brain imaging (e.g., a midline shift) and physical examination (e.g., papilledema) can indicate ICP elevation, but may not be able to rule it out. Therefore, ICP monitoring and quantification are vital in at-risk patients. Management usually involves expedited surgery of resectable or drainable lesions, conservative measures (e.g., positioning, sedation, analgesia, and antipyretics), and medical therapy (e.g., hyperosmolar therapy such as mannitol or hypertonic saline, or glucocorticoids). Treatment options for refractory intracranial hypertension include temporary controlled hyperventilation, CSF drainage, and decompressive craniectomy (DC), as well as other advanced medical therapies (e.g., barbiturate coma, therapeutic hypothermia).



  • Physiological ICP is ≤ 15 mm Hg in adults (in supine position), children generally have a lower ICP
  • ICP varies with the relative position of the head towards the rest of the body and is influenced by certain physiological processes (e.g., cardiac contractions, sneezing, coughing, Valsalva maneuver).
  • Expansion of either blood, CSF, or tissue within the skull → limited capacity for the intracranial volume to increase within the rigid skull → increase in intracranial pressure

Consequences of elevated ICP



Cerebral herniation syndromes


Neuroimaging (CT head/MRI head) [18]

Clinical examination and imaging may indicate elevated ICP, but cannot rule it out. Additionally, neither allow ICP to be quantified, which is necessary to determine CPP.

Invasive ICP monitoring

  • Invasive monitoring is typically required for confirmation and accurate measurement of ICP.
  • ICP should be evaluated in combination with CPP to guide therapeutic interventions and help prevent secondary brain injury and brain herniation. [19]
  • There are no absolute contraindications for invasive ICP monitoring.
  • Consider the risks versus the benefits in consultation with a specialist.

Indications [20][21][22]

Methods to monitor ICP [19][23][24]

Intraventricular catheters; with an external ventricular drain (EVD) and intraparenchymal catheters; (IPC) are most commonly used to monitor ICP, as they have the highest accuracy compared with other monitoring methods.

  • Intraventricular catheter: a monitoring device placed into the ventricles of the brain along with a CSF drainage system (i.e., an EVD) [25]
    • Allows for continuous ICP monitoring and evaluation of intracranial compliance
    • Useful in conditions in which CSF drainage is required for both diagnostic and therapeutic purposes
    • The preferred monitoring method for intracranial lesions associated with hydrocephalus [19]
    • Complications
      • Infections
      • Hemorrhage attributable to the placement of the device
      • Malpositioning and/or accidental removal
      • Blockage with blood or debris
  • Intraparenchymal catheter: a fiberoptic device placed into the brain parenchyma without an accompanying CSF drainage system [26]
    • Allows for continuous ICP monitoring
    • Accuracy and effect on patient outcomes are considered equivalent to intraventricular catheters
    • Lower risk of infection and hemorrhage compared with intraventricular catheters
    • Technical complications: e.g., dislodgement, breakage


  • Generally, ICP > 20 mm Hg indicates intracranial hypertension, which requires treatment. [19]
  • ICP varies in a complex cyclical manner and is influenced by hemodynamic and metabolic factors.
  • Monitor ICP along with MAP to calculate CPP using the formula CPP = MAP − ICP.

Do not use the ICP value in isolation as a prognostic marker or to inform therapeutic decisions. [19]

Approach [18][19][21][27][28][29]

Stepwise ICP management (based on a multifactorial response) [18][27][30][31]
Step Intervention
Initial steps
  • Identify and expedite the treatment of lesions that are amenable to emergency surgical procedures.
Subsequent step
  • Add medical therapy (e.g., hyperosmolar therapy).
Elective temporizing step
  • Consider short-term (< 30 minutes) controlled hyperventilation in patients with signs of imminent brain herniation and refractory elevated ICP in the interim while waiting for:
    • Surgical procedures
    • Onset of action of medical therapy
Advanced steps
  • General therapeutic targets: Base treatment decisions on trends identified using repeat assessments of ICP, CPP, and clinical status. [19][21]
    • Target ICP: < 20 mm Hg
    • Target CPP range: 60–70 mm Hg

Conservative therapy [32]

See also “Neuroprotective measures.”

Medical therapy [32]

Overview of hyperosmolar therapies in ICP management [32][39][40][41]
Mannitol HTS
Pharmacology [18][21]
  • Mannitol 20% is most commonly used.
  • Lowers ICP within minutes of administration
  • Peak efficacy: 20–60 minutes after administration
  • Duration of effect: 4–6 hours
  • Multiple concentrations of HTS exist (e.g., 3–23.4%), with highly variable dosages and pharmacokinetics. [32]
  • 23.4% HTS is commonly used.
Therapeutic targets to consider [27][32][33]
  • Symptom-based dosing is recommended for patients with SAH.
  • Serum osmolarity (e.g., 300–320 mOsm/L) or osmolar gap
  • Serum sodium (e.g., 145–155 mEq/L) [18][42][43]
Adverse effects [18][27][29]
Considerations [18]

Although hyperosmolar therapies can lower ICP, they have not been shown to improve neurological outcomes in patients with underlying TBI, acute ischemic stroke, ICH, SAH, or hepatic encephalopathy. [32]

Surgical therapy

  • Emergency surgery (if possible): e.g., resection of brain tumor, hematoma evacuation [29]
  • CSF drainage
  • Decompressive craniectomy (DC): removal of a portion of the skull, which allows the brain to expand in volume, thereby reducing ICP [45]
    • Primary DC: removal of a skull flap following evacuation or resection of an intracranial lesion (e.g., brain tumor)
    • Secondary DC: removal of a skull flap without additional surgical procedures to treat refractory elevated ICP
      • Recommended for (controversial): [45]
      • Not recommended for patients with early refractory elevated ICP
    • Multiple approaches have been described in the literature (suboccipital, subtemporal, frontotemporoparietal, etc.) depending on the type and location of the brain lesion. [47]
    • Lowers mortality in TBI without improving neurological or functional outcomes [28]

Nonsurgical therapy for refractory intracranial hypertension [32]

Controlled hyperventilation

Hyperventilation is primarily used as a temporizing measure for intracranial hypertension refractory to medical therapy. [30]

Controlled hyperventilation should only be used short-term and is not recommended routinely or for prophylaxis. Avoid excessive hyperventilation (PaCO2 < 30 mm Hg), prolonged hyperventilation, and hypoventilation of any kind, as CBF and perfusion may become compromised.

Advanced therapies

These are primarily reserved for patients with persistently refractory intracranial hypertension.

Irreversible loss of brain function (brain death)

  • Definition: irreversible, complete loss of function of the entire brain (including the brainstem), even if cardiopulmonary functions can be upheld by artificial life support.
  • Practical steps for determination of brain death: The American Academy of Neurology has published a practical guide that consists of four steps. It cites specific measures and interpretations (e.g., limits of body temperature) that can be used to determine brain death, although not all of them are evidence-based
  • Management

Requirements for the diagnosis of brain death

If spontaneous breathing is present, the medulla is intact! If the corneal reflex is present, the pons is intact! If the pupillary light reflex is present, the midbrain is intact!

Cerebral edema


We list the most important complications. The selection is not exhaustive.

  1. Smith ER. Evaluation and management of elevated intracranial pressure in adults. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/evaluation-and-management-of-elevated-intracranial-pressure-in-adults?source=machineLearning&search=intracranial%20pressure&selectedTitle=1~150&anchor=H2§ionRank=1#H9.Last updated: July 10, 2013. Accessed: February 19, 2017.
  2. Hackett JG, Abboud FM, Mark AL, Schmid PG, Heistad DD. Coronary vascular responses to stimulation of chemoreceptors and baroreceptors: evidence for reflex activation of vagal cholinergic innervation. Circ Res. 1972; 31 (1): p.8-17.
  3. Gupta G. Intracranial Pressure Monitoring. Intracranial Pressure Monitoring. New York, NY: WebMD. http://emedicine.medscape.com/article/1829950-overview. Updated: September 17, 2015. Accessed: February 19, 2017.
  4. Gans MS. Idiopathic Intracranial Hypertension. Idiopathic Intracranial Hypertension. New York, NY: WebMD. http://emedicine.medscape.com/article/1214410-overview. Updated: January 28, 2016. Accessed: March 1, 2017.
  5. Meningitis. http://www.pathophys.org/meningitis/. Updated: October 22, 2012. Accessed: March 1, 2017.
  6. Liebeskind DS. Intracranial Hemorrhage. Intracranial Hemorrhage. New York, NY: WebMD. http://emedicine.medscape.com/article/1163977-overview. Updated: May 10, 2016. Accessed: March 1, 2017.
  7. Lo BM. Brain Neoplasms. Brain Neoplasms. New York, NY: WebMD. http://emedicine.medscape.com/article/779664-overview. Updated: November 9, 2015. Accessed: February 19, 2017.
  8. Nelson SL. Hydrocephalus. In: Chawla J, Hydrocephalus. New York, NY: WebMD. http://emedicine.medscape.com/article/1135286-overview#a1. Updated: April 13, 2016. Accessed: December 14, 2016.
  9. Shah AK, Fuerst D, Sood S et al. Seizures Lead to Elevation of Intracranial Pressure in Children Undergoing Invasive EEG Monitoring. Epilepsia. 2017; 48 (6): p.1097-1103. doi: 10.1111/j.1528-1167.2006.00975.x . | Open in Read by QxMD
  10. Sunset eye sign. https://radiopaedia.org/articles/sunset-eye-sign. Updated: March 1, 2017. Accessed: March 1, 2017.
  11. Tasker RC. Elevated intracranial pressure (ICP) in children: Clinical manifestations and diagnosis. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/elevated-intracranial-pressure-icp-in-children-clinical-manifestations-and-diagnosis.Last updated: February 2, 2017. Accessed: March 1, 2017.
  12. Subfalcine Herniation. https://radiopaedia.org/articles/subfalcine-herniation. . Accessed: April 17, 2018.
  13. Pericallosal artery occlusion. https://radiopaedia.org/cases/pericallosal-artery-occlusion. Updated: March 1, 2017. Accessed: March 1, 2017.
  14. Traumatic Brain Injury and Increased Intracranial Pressure. http://neuropathology-web.org/chapter4/chapter4cHerniations.html. Updated: March 1, 2017. Accessed: March 1, 2017.
  15. Goetz CG. Textbook of Clinical Neurology. Elsevier ; 2007
  16. Cerebral herniation. https://radiopaedia.org/articles/cerebral-herniation. Updated: March 1, 2017. Accessed: March 1, 2017.
  17. Herniation Syndromes. http://casemed.case.edu/clerkships/neurology/NeurLrngObjectives/Herniation%20syndromes.htm. Updated: July 17, 2006. Accessed: March 1, 2017.
  18. Walls R, Hockberger R, Gausche-Hill M. Rosen's Emergency Medicine. Elsevier Health Sciences ; 2018
  19. Changa AR, Czeisler BM, Lord AS. Management of Elevated Intracranial Pressure: a Review. Curr Neurol Neurosci Rep. 2019; 19 (12): p.99. doi: 10.1007/s11910-019-1010-3 . | Open in Read by QxMD
  20. Le Roux P, Menon DK, Citerio G, et al. Consensus Summary Statement of the International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care. Neurocrit Care. 2014; 21 (S2): p.1-26. doi: 10.1007/s12028-014-0041-5 . | Open in Read by QxMD
  21. Wagner KE et al.. Trauma. Oper Neurosurg. 2019; 17 (Supplement_1): p.S45-S75. doi: 10.1093/ons/opz089 . | Open in Read by QxMD
  22. Carney N, Totten AM, O’Reilly C, et al. Guidelines for the Management of Severe Traumatic Brain Injury, Fourth Edition. Neurosurgery. 2016; 80 (1): p.6-15. doi: 10.1227/neu.0000000000001432 . | Open in Read by QxMD
  23. Kristiansson H et al.. Measuring Elevated Intracranial Pressure through Noninvasive Methods. J Neurosurg Anesthesiol. 2013; 25 (4): p.372-385. doi: 10.1097/ana.0b013e31829795ce . | Open in Read by QxMD
  24. Dimitriou J et al.. Comparison of Complications in Patients Receiving Different Types of Intracranial Pressure Monitoring: A Retrospective Study in a Single Center in Switzerland. World Neurosurg. 2016; 89 : p.641-646. doi: 10.1016/j.wneu.2015.11.037 . | Open in Read by QxMD
  25. Fried HI, Nathan BR, Rowe AS, et al. The Insertion and Management of External Ventricular Drains: An Evidence-Based Consensus Statement. Neurocrit Care. 2016; 24 (1): p.61-81. doi: 10.1007/s12028-015-0224-8 . | Open in Read by QxMD
  26. Volovici V, Huijben JA, Ercole A, et al. Ventricular Drainage Catheters versus Intracranial Parenchymal Catheters for Intracranial Pressure Monitoring-Based Management of Traumatic Brain Injury: A Systematic Review and Meta-Analysis. J Neurotrauma. 2019; 36 (7): p.988-995. doi: 10.1089/neu.2018.6086 . | Open in Read by QxMD
  27. Winn HR. Youmans and Winn Neurological Surgery. Elsevier ; 2016
  28. Hutchinson PJ, Kolias AG, Timofeev IS, et al. Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension. N Engl J Med. 2016; 375 (12): p.1119-1130. doi: 10.1056/nejmoa1605215 . | Open in Read by QxMD
  29. Esquenazi Y, Lo VP, Lee K. Critical Care Management of Cerebral Edema in Brain Tumors. J Intensive Care Med. 2016; 32 (1): p.15-24. doi: 10.1177/0885066615619618 . | Open in Read by QxMD
  30. Rabinstein AA et al. Neurological Emergencies. Springer International Publishing ; 2020
  31. Schizodimos T, Soulountsi V, Iasonidou C, Kapravelos N. An overview of management of intracranial hypertension in the intensive care unit. J Anesth. 2020; 34 (5): p.741-757. doi: 10.1007/s00540-020-02795-7 . | Open in Read by QxMD
  32. Cook AM, Morgan Jones G, Hawryluk GWJ, et al. Guidelines for the Acute Treatment of Cerebral Edema in Neurocritical Care Patients. Neurocrit Care. 2020; 32 (3): p.647-666. doi: 10.1007/s12028-020-00959-7 . | Open in Read by QxMD
  33. Torbey MT, Bösel J, Rhoney DH, et al. Evidence-Based Guidelines for the Management of Large Hemispheric Infarction. Neurocrit Care. 2015; 22 (1): p.146-164. doi: 10.1007/s12028-014-0085-6 . | Open in Read by QxMD
  34. Burgess S, Abu-Laban RB, Slavik RS, Vu EN, Zed PJ. A Systematic Review of Randomized Controlled Trials Comparing Hypertonic Sodium Solutions and Mannitol for Traumatic Brain Injury. Ann Pharmacother. 2016; 50 (4): p.291-300. doi: 10.1177/1060028016628893 . | Open in Read by QxMD
  35. Miyoshi Y, Kondo Y, et al. Effects of hypertonic saline versus mannitol in patients with traumatic brain injury in prehospital, emergency department, and intensive care unit settings: a systematic review and meta-analysis. Journal of Intensive Care. 2020; 8 (1). doi: 10.1186/s40560-020-00476-x . | Open in Read by QxMD
  36. Chen H, Song Z, Dennis JA. Hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury. Cochrane Database of Systematic Reviews. 2020 . doi: 10.1002/14651858.cd010904.pub3 . | Open in Read by QxMD
  37. Quintard H, Meyfroidt G, Citerio G. Hyperosmolar Agents for TBI: All Are Equal, But Some Are More Equal Than Others?. Neurocrit Care. 2020; 33 (2): p.613–614. doi: 10.1007/s12028-020-01063-6 . | Open in Read by QxMD
  38. Cook AM, Shutter L. Response to Drs. Quintard, et al.. Neurocrit Care. 2020; 33 (2): p.615-616. doi: 10.1007/s12028-020-01064-5 . | Open in Read by QxMD
  39. Rowland MJ, Veenith T, Hutchinson PJ, Perkins GD. Osmotherapy in traumatic brain injury. The Lancet Neurology. 2020; 19 (3): p.208. doi: 10.1016/s1474-4422(20)30003-x . | Open in Read by QxMD
  40. Mangat HS. Hypertonic saline infusion for treating intracranial hypertension after severe traumatic brain injury. Critical Care. 2018; 22 (1): p.37. doi: 10.1186/s13054-018-1963-7 . | Open in Read by QxMD
  41. Boone M, Oren-Grinberg A, Robinson T, Chen C, Kasper E. Mannitol or hypertonic saline in the setting of traumatic brain injury: What have we learned?. Surgical Neurology International. 2015; 6 (1): p.177. doi: 10.4103/2152-7806.170248 . | Open in Read by QxMD
  42. Wagner I, Hauer E-M, Staykov D, et al. Effects of Continuous Hypertonic Saline Infusion on Perihemorrhagic Edema Evolution. Stroke. 2011; 42 (6): p.1540-1545. doi: 10.1161/strokeaha.110.609479 . | Open in Read by QxMD
  43. Wells DL, Swanson JM, Wood GC, et al. The relationship between serum sodium and intracranial pressure when using hypertonic saline to target mild hypernatremia in patients with head trauma. Critical Care. 2012; 16 (5): p.R193. doi: 10.1186/cc11678 . | Open in Read by QxMD
  44. Ryken TC, McDermott M, Robinson PD, et al. The role of steroids in the management of brain metastases: a systematic review and evidence-based clinical practice guideline. J Neurooncol. 2009; 96 (1): p.103-114. doi: 10.1007/s11060-009-0057-4 . | Open in Read by QxMD
  45. Hawryluk GWJ, Rubiano AM, Totten AM, et al. Guidelines for the Management of Severe Traumatic Brain Injury: 2020 Update of the Decompressive Craniectomy Recommendations. Neurosurgery. 2020; 87 (3): p.427-434. doi: 10.1093/neuros/nyaa278 . | Open in Read by QxMD
  46. Honeybul S, Ho KM, Gillett G. Outcome Following Decompressive Hemicraniectomy for Malignant Cerebral Infarction. Stroke. 2015; 46 (9): p.2695-2698. doi: 10.1161/strokeaha.115.010078 . | Open in Read by QxMD
  47. Bullock MR, Chesnut R, Ghajar J, et al. Guidelines for the Surgical Management of Traumatic Brain Injury Author Group. Neurosurgery. 2006; 58 (3): p.S2-vi-S2-vi. doi: 10.1093/neurosurgery/58.3.vi . | Open in Read by QxMD
  48. Godoy DA, Seifi A, Garza D, Lubillo-Montenegro S, Murillo-Cabezas F. Hyperventilation Therapy for Control of Posttraumatic Intracranial Hypertension. Frontiers in Neurology. 2017; 8 : p.250. doi: 10.3389/fneur.2017.00250 . | Open in Read by QxMD
  49. Clark J, Ellens N, Figueroa B. The use of barbiturate-induced coma during cerebrovascular neurosurgery procedures: A review of the literature. Brain Circulation. 2015; 1 (2): p.140. doi: 10.4103/2394-8108.172887 . | Open in Read by QxMD
  50. Roberts I, Sydenham E. Barbiturates for acute traumatic brain injury. Cochrane Database of Systematic Reviews. 2012 : p.CD000033. doi: 10.1002/14651858.cd000033.pub2 . | Open in Read by QxMD
  51. Crompton EM, Lubomirova I, Cotlarciuc I, Han TS, Sharma SD, Sharma P. Meta-Analysis of Therapeutic Hypothermia for Traumatic Brain Injury in Adult and Pediatric Patients. Crit Care Med. 2017; 45 (4): p.575-583. doi: 10.1097/ccm.0000000000002205 . | Open in Read by QxMD
  52. Andrews PJ, Sinclair HL, Rodríguez A, et al. Therapeutic hypothermia to reduce intracranial pressure after traumatic brain injury: the Eurotherm3235 RCT. Health Technol Assess (Rockv). 2018; 22 (45): p.1-134. doi: 10.3310/hta22450 . | Open in Read by QxMD
  53. Watson HI, Shepherd AA, Rhodes JKJ, Andrews PJD. Revisited: A Systematic Review of Therapeutic Hypothermia for Adult Patients Following Traumatic Brain Injury. Crit Care Med. 2018; 46 (6): p.972-979. doi: 10.1097/ccm.0000000000003125 . | Open in Read by QxMD
  54. Andrews et al.. Hypothermia for Intracranial Hypertension after Traumatic Brain Injury. New England Journal of Medicine. 2015; 373 (25): p.2403-2412. doi: 10.1056/nejmoa1507581 . | Open in Read by QxMD
  55. Chen H, Wu F, Yang P, Shao J, Chen Q, Zheng R. A meta-analysis of the effects of therapeutic hypothermia in adult patients with traumatic brain injury. Critical Care. 2019; 23 (1): p.396. doi: 10.1186/s13054-019-2667-3 . | Open in Read by QxMD
  56. Karnatovskaia LV, Lee AS, Festic E, Kramer CL, Freeman WD. Effect of Prolonged Therapeutic Hypothermia on Intracranial Pressure, Organ Function, and Hospital Outcomes Among Patients with Aneurysmal Subarachnoid Hemorrhage. Neurocrit Care. 2014; 21 (3): p.451-461. doi: 10.1007/s12028-014-9989-4 . | Open in Read by QxMD
  57. Scott JB, Gentile MA, Bennett SN, Couture M, MacIntyre NR. Apnea testing during brain death assessment: a review of clinical practice and published literature. Respir Care. 2013; 58 (3): p.532-538. doi: 10.4187/respcare.01962 . | Open in Read by QxMD
  58. Marmarou A. A review of progress in understanding the pathophysiology and treatment of brain edema. Neurosurg Focus. 2007; 22 (5): p.E1.
  59. Rao JVI, Vengamma B, Naveen T, Naveen V. Lead encephalopathy in adults. J Neurosci Rural Pract. 2014; 5 (2): p.161-163. doi: 10.4103/0976-3147.131665 . | Open in Read by QxMD
  60. Kasper DL, Fauci AS, Hauser SL, Longo DL, Lameson JL, Loscalzo J. Harrison's Principles of Internal Medicine. McGraw-Hill Education ; 2015
  61. Wijdicks EF, Varelas PN, Gronseth GS, Greer DM, American Academy of Neurology. Evidence-based guideline update: determining brain death in adults: report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 2010; 74 (23): p.1911-1918. doi: 10.1212/WNL.0b013e3181e242a8 . | Open in Read by QxMD
  62. Devastating brain injuries: assessment and management part I: overview of brain death. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2672297/pdf/0100011.pdf. Updated: February 1, 2009. Accessed: February 19, 2017.
  63. Young GB. Diagnosis of brain death. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/diagnosis-of-brain-death?source=machineLearning&search=brain%20death&selectedTitle=1~150§ionRank=1&anchor=H2#H2.Last updated: May 27, 2015. Accessed: February 19, 2017.
  64. Schofield GM, Urch CE, Stebbing J, Giamas G. When does a human being die?. QJM. 2014; 108 (8): p.605-609. doi: 10.1093/qjmed/hcu239 . | Open in Read by QxMD
  65. Increased Intracranial Pressure. http://www.healthline.com/health/increased-intracranial-pressure#Overview1. Updated: October 22, 2015. Accessed: March 1, 2017.