title: Autoregulation and brain metabolism in the perihematomal region of spontaneous intracerebral hemorrhage: an observational pilot study.
abstract: The metabolic and hemodynamic processes in the edema surrounding spontaneous, supratentorial intracerebral hemorrhage (ICH) are poorly understood. Specifically, the local metabolic effects of autoregulatory failure have not been described previously. In the current observational pilot study, microdialysis and brain tissue oxygenation probes (P(br)O(2)) were placed in the perihemorrhagic edema using neuronavigation in five non-surgically treated patients with deep ICH. The cerebrovascular pressure reactivity index (PRx, moving correlation between mean arterial and intracranial pressure) and P(br)O(2) reactivity index (ORx, correlation between P(br)O(2) and cerebral perfusion pressure) were used to characterize cerebral autoregulation. While all five patients had ORx values indicative for severely disturbed autoregulation, assessment of PRx only in one patient was consistent with sustained failure of cerebrovascular reactivity. This patient at the same time had the worst metabolic parameters and the poorest tissue oxygenation. We conclude that multimodality monitoring in the perihemorrhagic penumbra is feasible. A study in a larger population is needed to clarify the relationship between PRx and ORx in ICH patients, the local metabolic effects of autoregulatory failure and its relation to brain edema formation and clinical outcome.
authors.affiliation: Department of Neurology, University of Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany. Jennifer.diedler@med.uni-heidelberg.de
authors.forename: Jennifer
authors.initials: J
authors.lastname: Diedler
authors.forename: Georg
authors.initials: G
authors.lastname: Karpel-Massler
authors.forename: Marek
authors.initials: M
authors.lastname: Sykora
authors.forename: Sven
authors.initials: S
authors.lastname: Poli
authors.forename: Oliver W
authors.initials: OW
authors.lastname: Sakowitz
authors.forename: Roland
authors.initials: R
authors.lastname: Veltkamp
authors.forename: Thorsten
authors.initials: T
authors.lastname: Steiner
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D001921:Brain / Q000378:metabolism*; D001929:Brain Edema / Q000209:etiology; D002543:Cerebral Hemorrhage / Q000150:complications* / Q000473:pathology*; D002560:Cerebrovascular Circulation; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D007427:Intracranial Pressure / Q000502:physiology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D017551:Microdialysis / Q000379:methods; D008875:Middle Aged; D019370:Observation; D010101:Oxygen Consumption / Q000502:physiology; D010865:Pilot Projects; D012189:Retrospective Studies; D013997:Time Factors