Hi Megan! Thanks for this question! Normal values for ICP vary slightly depending on the reference. Generally, values less than 15 mmHg are considered normal. Values greater than 20-25 mmHg usually require treatment. On the NCS exam, they likely won’t ask questions requiring you to determine next steps on the gray areas (10-20 mmHg).
Here are a few values from the literature:
– Supine adult : 7-15 mmHg
– Standing adult : -10 mmHg
– Normal values in adults and older children : <10-15 mmHg
- Mild intracranial hypertension : 20-30 mmHg
- Severe, life-threatening hypertension : >40 mmHg
 Rangel-Castillo L, Gopinath S, Robertson CS. Management of intracranial hypertension. Neurol Clin. 2008;26(2):521-541.
 Haider MN, Leddy JJ, Hinds AL, et al. Intra-cranial pressure changes after mild traumatic brain injury: a systematic review. Brain Inj. 2018;32(7):809-815.