title: Identification of an Intracranial Pressure (ICP) Response Function from Continuously Acquired Electroencephalographic and ICP Signals in Burst-Suppressed Patients.
abstract: Continuous intracranial pressure (ICP) and electroencephalographic (EEG) monitoring are used in the management of patients with brain injury. It is possible that these two signals could be related through neurovascular coupling. To explore this mechanism, we modeled the ICP response to brain activity by treating spontaneous burst activity in burst-suppressed patients as an impulse, and identified the ICP response function (ICPRF) as the subsequent change in ICP.Segments of ICP were filtered, classified as elevating or stable, and suitable ICPRFs were identified. After calibration, each ICPRF was convolved with the EEG to produce the estimated ICP. The mean error (ME) versus distance from the selected ICPRF was calculated and the elevating and stable ICP segments compared.Eighty-four ICPRFs were identified from 15 data segments. The ME of the elevating segments increased at an average rate of 57 mmHg/min, whereas the average ME of the stable segments increased at a rate of 0.05 mmHg/min.These findings demonstrate that deriving an ICPRF from a burst-suppressed patient is a suitable approach for stable segments. To completely model the ICP response to EEG activity, a more robust model should be developed.
authors.affiliation: Department of Neurosurgery, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, CA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Connolly
authors.affiliation: Department of Neurosurgery, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, CA, USA.
authors.forename: Raymond
authors.initials: R
authors.lastname: Liou
authors.affiliation: Department of Neurosurgery, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, CA, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Vespa
authors.affiliation: Departments of Physiological Nursing/Neurosurgery, University of California-San Francisco, San Francisco, CA, USA. xhu@mednet.ucla.edu.|Institute for Computational Health Sciences, University of California-San Francisco, San Francisco, CA, USA. xhu@mednet.ucla.edu.|Affiliate, UCB/UCSF Graduate Group in Bioengineering, University of California-San Francisco, San Francisco, CA, USA. xhu@mednet.ucla.edu.
authors.forename: Xiao
authors.initials: X
authors.lastname: Hu
mesh_terms: D000328:Adult; D017542:Aneurysm, Ruptured / Q000150:complications; D000070642:Brain Injuries, Traumatic / Q000150:complications / Q000503:physiopathology*; D058256:Brain Waves / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D018757:GABA Modulators / Q000627:therapeutic use; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications; D019586:Intracranial Hypertension / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology*; D007427:Intracranial Pressure / Q000502:physiology*; D008875:Middle Aged; D000069336:Neurovascular Coupling / Q000502:physiology; D010424:Pentobarbital / Q000627:therapeutic use; D013345:Subarachnoid Hemorrhage / Q000209:etiology / Q000503:physiopathology*
chemical_list: D018757:GABA Modulators; D010424:Pentobarbital
keywords: Burst suppression; Intracranial pressure