Regional cerebral blood flow during hyperventilation in patients with acute bacterial meningitis

Clin Physiol. 2000 Sep;20(5):399-410. doi: 10.1046/j.1365-2281.2000.00276.x.


Mechanical hyperventilation is often instituted in patients with acute bacterial meningitis when increased intracranial pressure is suspected. However, the effect on regional cerebral blood flow (CBF) is unknown. In this study, we measured regional CBF (rCBF) in patients with acute bacterial meningitis before and during short-term hyperventilation. In 17 patients with acute bacterial meningitis, absolute rCBF (in ml/100 g min-1) was measured during baseline ventilation and hyperventilation by single-photon emission computed tomography (SPECT) using intravenous 133Xe bolus injection. Intravenous 99mTc-HMPAO (hexamethylpropyleneamine oxime) was subsequently given during hyperventilation. In 12 healthy volunteers, rCBF was measured by SPECT and 99mTc-HMPAO during spontaneous ventilation. Using standard templates to identify regions of interest (ROIs), we calculated rCBF in percentage of cerebellar (99mTc-HMPAO images) or mean hemispheric (133Xe images) flow for each ROI, the degree of side-to-side asymmetry for each ROI, and the anterior-to-posterior flow ratio. On 133Xe images, absolute rCBF decreased significantly during hyperventilation compared to baseline ventilation in all regions, but the relative rCBF did not change significantly from baseline ventilation (n=14) to hyperventilation (n=12), indicating that the perfusion distribution was unchanged. On 99mTc-HMPAO images (n=12), relative rCBF and the anterior-to-posterior flow ratio were significantly lower in patients than in controls in the frontal and parietal cortex as well as in the basal ganglia. Focal perfusion abnormalities were present in 10 of 12 patients. Regional cerebral blood flow abnormalities are frequent in patients with acute bacterial meningitis. Short-term hyperventilation does not enhance these abnormalities.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Blood Flow Velocity
  • Blood Gas Analysis
  • Brain / blood supply*
  • Brain / diagnostic imaging
  • Cerebrovascular Circulation*
  • Female
  • Humans
  • Hyperventilation / physiopathology*
  • Image Processing, Computer-Assisted
  • Injections, Intravenous
  • Male
  • Meningitis, Bacterial / diagnostic imaging*
  • Meningitis, Bacterial / physiopathology*
  • Middle Aged
  • Respiration, Artificial
  • Survival Rate
  • Technetium Tc 99m Exametazime / administration & dosage
  • Tomography, Emission-Computed, Single-Photon
  • Xenon Radioisotopes / administration & dosage


  • Xenon Radioisotopes
  • Technetium Tc 99m Exametazime