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A Detailed Protocol for Physiological Parameters Acquisition and Analysis in Neurosurgical Critical Patients
Published on: October 17, 2017
Resonant and notch behavior in intracranial pressure dynamics
Mark E Wagshul1, Erin J Kelly, Hui Jing Yu
1Department of Radiology, Stony Brook University, Stony Brook, New York 11794, USA. mark.wagshul@stonybrook.edu
Journal of Neurosurgery. Pediatrics
|May 5, 2009
Summary
Investigating intracranial pulse pressure in dogs revealed a resonant notch system that protects the brain. This system
Area of Science:
- Neuroscience
- Biomedical Engineering
- Physiology
Background:
- Intracranial pulse pressure often increases with neuropathology, especially in conditions like hydrocephalus.
- The coupling between arterial blood pressure and intracranial pressure (ICP) is well-established.
- Understanding this relationship is crucial for managing neurological conditions.
Purpose of the Study:
- To investigate the nature of the coupling between arterial blood pressure and ICP.
- To characterize how this coupling changes under conditions of increased ICP.
- To explore the implications for neurological disorders.
Main Methods:
- Measurements of intracarotid and parenchymal pulse pressure in 12 dogs.
- Characterization of pulse pressure coupling using amplitude and phase transfer function analysis.
- Manipulation of mean ICP via saline infusions and monitoring of transfer function changes.
Main Results:
- Under normal conditions, ICP waves led arterial waves with minimal pulse pressure amplitude near heart rate.
- With decreased intracranial compliance, ICP waves lagged arterial waves and amplitude increased significantly.
- A minimum pulse pressure amplitude was observed at the transition from leading to lagging ICP waves.
Conclusions:
- The observed transfer function behavior suggests a resonant notch system, potentially part of the intracranial Windkessel mechanism.
- This system may protect cerebral microvasculature from arterial pulsatility.
- Impairment of this system could contribute to altered pulse pressure in hydrocephalus and traumatic brain swelling, necessitating new therapeutic approaches.
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