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Updated: Jun 23, 2026
05:01
A Detailed Protocol for Physiological Parameters Acquisition and Analysis in Neurosurgical Critical Patients
Published on: October 17, 2017
[Intracranial pressure-volume relationship. Physiology and pathophysiology]
K Zweckberger1, O W Sakowitz, A W Unterberg
1Neurochirurgische Klinik, Universität Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Deutschland. klaus.zweckberger@med.uni-heidelberg.de
Der Anaesthesist
|April 23, 2009
Summary
Elevated intracranial pressure (ICP) after traumatic brain injury predicts patient outcomes. Understanding the pressure-volume index (PVI) and volume-pressure response (VPR) aids in assessing brain injury severity.
Area of Science:
- Neurology
- Neurosurgery
- Physiology
Context:
- Elevated intracranial pressure (ICP) is a critical prognostic indicator following traumatic brain injury (TBI).
- ICP increases exponentially after compensatory mechanisms are exhausted, impacting patient outcomes.
- Brain compliance and elasticity significantly influence the ICP curve.
Purpose:
- To explore the significance of the pressure-volume index (PVI) and volume-pressure response (VPR) in assessing intracranial dynamics.
- To highlight the non-linear relationship between pressure and volume in the cranio-spinal system.
- To emphasize the need for combined monitoring techniques for comprehensive brain injury assessment.
Summary:
- The pressure-volume index (PVI) quantifies the volume needed to increase ICP tenfold, reflecting brain elasticity.
- Volume-pressure response (VPR) offers continuous intracranial compliance measurement based on pulsatile volume changes.
- Marmarou's work established a logarithmic, mono-exponential relationship in the pressure-volume index.
Impact:
- Provides insights into the biomechanical properties of the injured brain.
- Introduces key metrics (PVI, VPR) for evaluating intracranial pressure dynamics.
- Recommends a multimodal approach combining ICP monitoring with tissue oxygen, cerebral blood flow, microdialysis, and electrocorticography for better functional assessment.
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