Cerebral oxygen metabolism after aneurysmal subarachnoid hemorrhage

J Cereb Blood Flow Metab. 1991 Sep;11(5):837-44. doi: 10.1038/jcbfm.1991.143.


Previous studies of cerebral oxygen metabolism and extraction in patients with subarachnoid hemorrhage (SAH) have yielded conflicting results. We used positron emission tomography (PET) to measure the regional cerebral metabolic rate for oxygen (rCMRO2), oxygen extraction fraction (rOEF), and cerebral blood flow (rCBF) 16 times in 11 patients with aneurysmal SAH. All studies were performed preoperatively; no patient had hydrocephalus or intracerebral hematoma on brain CT. Eight patients with no arteriographic vasospasm who were studied on days 1-4 post-SAH had a significant 25% reduction in global CMRO2 compared to age-matched controls, and no significant change in global OEF, suggesting a primary reduction in CMRO2 caused by SAH. Four patients studied seven times during arteriographic vasospasm had significantly increased rOEF with unchanged CMRO2 in arterial territories affected by arteriographic vasospasm compared to territories without vasospasm, indicative of cerebral ischemia without infarction. No brain regions studied with PET were infarcted on follow-up CT. We conclude that the initial aneurysm rupture produces a primary reduction in CMRO2, and that subsequent vasospasm causes ischemia.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Cerebrovascular Circulation
  • Female
  • Humans
  • Intracranial Aneurysm / complications
  • Intracranial Aneurysm / diagnostic imaging
  • Intracranial Aneurysm / metabolism*
  • Male
  • Middle Aged
  • Oxygen / metabolism*
  • Oxygen Consumption*
  • Subarachnoid Hemorrhage / diagnostic imaging
  • Subarachnoid Hemorrhage / etiology
  • Subarachnoid Hemorrhage / metabolism*
  • Subarachnoid Hemorrhage / physiopathology
  • Tomography, Emission-Computed


  • Oxygen