**Author details**

*Advancement and New Understanding in Brain Injury*

celerity to this multimodal scenario [47, 48].

**4.4 Increased ICP outside ICU environment**

consciousness and focal deficits [49, 50].

practice raise the yellow sign on the need for ICC evaluation.

sheath tumors [52].

**5. Conclusions**

in a near future.

retina, and pupil, besides the routinely used imaging exams of CT-scan and MRI [23, 42, 43, 45]. There is also a new non-invasive method of ICP monitoring that provides morphological data of ICP waves and intracranial compliance, adding

It is well established that ICH is an important issue after TBI because of its relationship to overall outcomes and all guidelines recommend a comprehensive ICP assessment – either invasively or non-invasively. Information about absolute values and waveform characteristics of ICP may together contribute to direct optimal management of TBI and good patient care [23, 42, 43, 45, 47, 48].

The brain constitutes approximately 80% of intracranial volume, and blood and CSF each account for 10% [49–51]. The first compensatory mechanism for maintenance of normal ICP involves displacement and reduction of the CSF compartment, reduction of CBF, and lastly, displacement of cerebral parenchyma causing herniation. The slower the increment in ICP, the more useful this regulatory system. Therefore, rapidly growing masses like malignant gliomas have a higher risk of causing brain herniation than slow-growing tumors like meningiomas or nerve

Transient elevation in ICP, generally from 50 to 100 mmHg and 5 to 20 minutes, leads to plateau wave phenomena. It can occur spontaneously or start after coughing, sneezing, or changes in position. This transient intracranial hypertension period may be accompanied also by transient headache, transient alteration of the level of

Obesity and its relation with sleep apnea obstructive syndrome may show ICC impairment due to overnight hypercarbia leading to cerebral vasodilation. Also, this population is likely to develop chronic idiopathic intracranial hypertension. Moreover, hydrocephalus patients of any etiology, migraineurs, progressive neurological focal and/or gait disorders, all these situations mentioned here for outpatients

Advances on cerebral hemodynamics and intracranial compliance understanding brought to light by recent researches have made monitoring of these properties an essential practice in critical care. Likewise, advances in technology may convert intracranial compliance in a new vital sign present in daily practice

**10**

Gustavo Frigieri1 \*, Cintya Yukie Hayashi<sup>2</sup> , Nicollas Nunes Rabelo2 and Sérgio Brasil2

1 Scientific Department, Brain4care, São Paulo, Brazil

2 Department of Neurology, University of São Paulo, São Paulo, Brazil

\*Address all correspondence to: gustavo.frigieri@brain4.care

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
