title: Characterization of the relationship between intracranial pressure and electroencephalographic monitoring in burst-suppressed patients.
abstract: BACKGROUND
  The objective of this study is to characterize the relationship between ICP and EEG METHODS: Simultaneous ICP and EEG data were obtained from burst-suppressed patients and segmented by EEG bursts. Segments were categorized as increasing/decreasing and peak/valley to investigate relationship between ICP changes and EEG burst duration. A generalized ICP response was obtained by averaging all segments time-aligned at burst onsets. A vasodilatation index (VDI) was derived from the ICP pulse waveform and calculated on a sliding interval to investigate cerebrovascular changes post-burst.
  
  
  RESULTS
  Data from two patients contained 309 bursts. 246 ICP segments initially increased, of which 154 peaked. 63 ICP segments decreased, and zero reached a valley. The change in ICP (0.54 ± 0.85 mmHg) was significantly correlated with the burst duration (p < 0.001). Characterization of the ICP segments showed a peak at 8.1 s and a return to baseline at 14.7 s. The VDI for increasing segments was significantly elevated (median 0.56, IQR 0.31, p < 0.001) and correlated with burst duration (p < 0.001).
  
  
  CONCLUSIONS
  Changes in the ICP and pulse waveform shape after EEG burst suggest that these signals can be related within the context of neurovascular coupling.
  
  
  CONCLUSIONS
  Existence of a physiological relationship between ICP and EEG may allow the study of neurovascular coupling in acute brain injury patients.
authors.affiliation: Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Connolly
authors.forename: Paul
authors.initials: P
authors.lastname: Vespa
authors.forename: Nader
authors.initials: N
authors.lastname: Pouratian
authors.forename: Nestor R
authors.initials: NR
authors.lastname: Gonzalez
authors.forename: Xiao
authors.initials: X
authors.lastname: Hu
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000175:diagnosis / Q000503:physiopathology*; D058256:Brain Waves / Q000502:physiology*; D005260:Female; D006801:Humans; D007427:Intracranial Pressure / Q000502:physiology*; D008875:Middle Aged; D064926:Neurophysiological Monitoring; D000069336:Neurovascular Coupling / Q000502:physiology*