In eight subjects anesthetized with moderate to high doses of inhalation anesthetics (isoflurane or desflurane) during normocapnia, the onset of electrical silence in EEG was associated with a sudden reduction of blood flow velocity monitored from the middle cerebral artery. The magnitude of this reduction was 38 ± 11% (mean ± SD; range 24–44%). The change in EEG always preceded the change in flow velocity by 5–7 s. These observations suggest that some flow–metabolism coupling mechanism is preserved during inhalation anesthesia in humans.
AaslidR, (1987) Visually evoked dynamic blood flow response of the human cerebral circulation. Stroke18:771–775
2.
AaslidRLindegaardKFSortebergWNornesH, (1989) Cerebral autoregulation in humans. Stroke20:45–52
3.
BendoAAHartungJKassISCottrellJE, (1992) Neurophysiology and neuroanesthesia. In: Clinical Anesthesia, 2nd ed (BarashPGCullenBFStoeltingRK, eds), Philadelphia, Lippincott, pp 872–918
4.
DrosteDWHardersAGRastogiE, (1989) A transcranial Doppler study of blood flow velocity in the middle cerebral arteries performed at rest and during mental activities. Stroke20:1005–1011
5.
EngCLamAMMaybergTSMathisenTLLeeC, (1992) Influence of propofol with and without nitrous oxide on cerebral blood flow velocity and carbon dioxide reactivity in humans. Anesthesiology77:872–879
6.
GillerCABowmanGDyerHMootzLKrippnerW, (1993) Cerebral arterial diameters during changes in blood pressure and carbon dioxide during craniotomy. Neurosurgery32:737–741
7.
HansenTDWarnerDSToddMMVustLJ, (1989) The role of cerebral metabolism in determining the local cerebral blood flow effects of volatile anesthetics: Evidence for persistent flow–metabolism coupling. J Cereb Blood Flow Metab9:323–328
8.
HardersAGLabordeGDrosteDWRastogiE, (1989) Brain activity and blood flow velocity changes: A transcranial Doppler study. Int J Neurosci47:91–102
9.
IbayashiSNgaiACHowardMAMenoJRMaybergMRWinnHR, (1991) Lack of sympathetic and cholinergic influences on cerebral vasodilation caused by sciatic nerve stimulation in the rat. J Cereb Blood Flow Metab11:678–683
10.
LamAMMaybergTSEngCCCooperJOBachenbergKLMathisenTL, (1994) Nitrous oxide-isoflurane anesthesia causes more cerebral vasodilation than an equipotent dose of isoflurane in humans. Anesth Analg78:462–468
11.
McPhersonRWKirschJRMooreLETraystmanRJ, (1993) Nω-Nitro-l-arginine methyl ester prevents cerebral hyperemia by inhaled anesthetics in dogs. Anesth Analg77:891–897
12.
NgaiACKoKRMoriiSWinnHR, (1988) Effect of sciatic nerve stimulation or pial arterioles in rats. Am J Physiol254:H133–H139
13.
OlesonJ, (1972) The effect of intracarotid epinephrine, norepinephrine, and angiotensin on the regional cerebral blood flow in man. Neurology22:978–987
14.
OlsenKSHenriksenLOwen-FalkenbergADige-PetersenHRosenørnJChraemmer-JorgensenB, (1994) Effect of 1 or 2 MAC isoflurane with or without ketanserin on cerebral blood flow autoregulation in man. Br J Anaesth72:66–71
15.
WeiHMWeissHRSinhaAKChiOZ, (1993) Effects of nitric oxide synthase inhibition on regional cerebral blood flow and vascular resistance in conscious and isoflurane-anesthetized rats. Anesth Analg77:880–885
16.
WinnHRRubioGRBerneRM, (1981) The role of adenosine in the regulation of cerebral blood flow. J Cereb Blood Flow Metab1:239–244
