Cerebral Blood Flow and Oxygen Consumption in Man

Lassen, Niels A.

doi:10.1152/physrev.1959.39.2.183

Cited by 1,829 publications

(1,029 citation statements)

References 25 publications

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“…When the Kety-Schmidt method was applied to carefully selected, elderly subjects in a clearly supe rior state of health, no age-dependent decline was found in mean CBF or mean CMR02 (Dastur et aI., 1963;Sokoloff, 1978). In more average elderly sub jects, some reduction has been found in mean CBF and mean CMR02, which is exaggerated by cerebral disease (e.g., Lassen, 1959;Dastur et a!., 1963;Ob rist, 1978;Sokoloff, 1978;Gottstein and Held, 1979;Naritomi et aI., 1979;Frackowiak et aI., 1980;Melamed et aI., 1980;Lammertsma et aI., 1981). It has been noted that the decline in mean CMRg\u is more marked than the decline in mean CBF or mean CMR02 (Dastur et aI., 1963;Gottstein et aI., 197 1;Gottstein and Held, 1979).…”

Section: Figmentioning

confidence: 99%

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [¹⁸F] Fluorodeoxyglucose Method

et al. 1982

J Cereb Blood Flow Metab

318

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Summary:The [IHF]fluorodeoxyglucose (FDG) scan method with positron emission computed tomography was used to determine patterns of local cere bral glucose utilization (LCMRg1u) in 40 normal volunteer subjects aged 18 to 78 years. Throughout all the studies. each subject was quiet, without movement, with eyes open and ears unplugged, exposed only to ambient room light and sound. For the entire group, whole brain mean CMRglu was 26.1 ± 6. I /Lmol 100 g-l min-1 (mean ± SD, n = 40). At age 78, mean CMRglu was, on the average, 26% less than at age 18, an alteration of the same order as the variance among subjects at any age. The gradual decline of mean CMRglu with advancing age occurred at a faster rate than was reported for mean cerebral oxygen utilization, possibly due to increasingly altered pathways for glucose utilization, or to increasing oxidation of ketone bodies or other alternative substrates. Glucose utilization in the hemispheres was symmetrical and mean CMRglU of overall cortex, caudate, and thalamus was equal in individuals at all ages. The slopes of decline with age were similar when LCM Rglu was averaged over zones corresponding to centrum semiovale, caudate, putamen, and fron tal, temporal, parietal, occipital, and primary visual cortex. However, the met abolic ratio of superior frontal cortex to superior parietal cortex declined with age, possibly due to selective degeneration of superior frontal cortex or to differences between age groups in the sensory and cognitive response to the study. These results should be useful in distinguishing age from disease effects when the FDG scan method is used. 163 koloff et aI., 1977) used in animals, but emission computed tomography is substituted for the au toradiography. After intravenous injection, FDG enters the brain, is phosphorylated by brain hexokinase, and the metabolic product, FDG-6-P0 4 , remains fixed with only slow dephosphoryla tion. The time course of specific activity is mea sured in plasma, brain activity is determined by scanning, and with knowledge of predetermined rate constants, an operational equation allows cal culations of LCMRglu that are distributed in a cross-

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Section: Figmentioning

confidence: 99%

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [¹⁸F] Fluorodeoxyglucose Method

et al. 1982

J Cereb Blood Flow Metab

318

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“…Similarly, it has been shown that the incidence of adverse neurologic outcomes is increased when cerebral perfusion pressure is not maintained above the lower limit of cerebral autoregulation (LLA) 2. The LLA is defined as the pressure below which blood flow in the brain becomes pressure dependent, and is often assumed to be a mean arterial blood pressure (MAP) of 50 mm Hg 3. However, previous studies by our group have questioned this assumption and demonstrated that during surgery and anesthesia, the range for the LLA varies considerably between 40 and 90 mm Hg 4.…”

Section: Introductionmentioning

confidence: 99%

Relationship Between the Ambulatory Arterial Stiffness Index and the Lower Limit of Cerebral Autoregulation During Cardiac Surgery

Obata

Barodka

Berkowitz

et al. 2018

JAHA

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BackgroundPulse pressure, the ambulatory arterial stiffness index (AASI), and the symmetric AASI are established predictors of adverse cardiovascular outcomes. However, little is known about their relationship to cerebral autoregulation. This study evaluated whether these markers of vascular properties relate to the lower limit of cerebral autoregulation (LLA).Methods and ResultsThe LLA was determined during cardiac surgery with transcranial Doppler ultrasonography in 181 patients. All other variables were calculated from continuous intraoperative readings obtained before cardiopulmonary bypass. The LLA varied directly with the AASI (β=3.12 per 0.1 change in AASI, P<0.001) and to a lesser extent the symmetric AASI (β=2.02 per 0.1 change in symmetric AASI, P≤0.022), while peripheral pulse pressure was not significantly related (β=0.0, P>0.99). Logistic regression revealed that the likelihood of LLA being >65 mm Hg increased by 50% (95% confidence interval, 11%–102%, P=0.008) for every 0.1 increase in the AASI. The AASI was able to predict a LLA above certain thresholds (area under the curve receiver operating characteristic for AASI predicting an LLA >65 mm Hg: 0.60; 95% confidence interval, 0.51%–0.68%, P=0.043). Incorporating additional variables improved the model's predictive ability (area under the curve for AASI predicting a LLA >65 mm Hg: 0.75; 95% confidence interval, 0.68–0.82, P=0.036).ConclusionsThese data indicate that the LLA is related to the mechanical properties of the vasculature as represented by the AASI. The AASI can be used to predict LLA threshold levels during cardiac surgery. It is now possible to link elevations in the LLA with an increased AASI as determined from readily accessible intraoperative variables.

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“…As blood gases were not altered after TRH administration, this reduction in pH may reflect the dissociation of tartaric acid from its complex with TRH. The intravascular in jection of a low pH solution does not result in CBF changes if P aco2 is maintained constantly and if the blood-brain barrier remains intact (Lassen, 1959;Harper and Bell, 1963). Thus, this slight decrease in pH is not considered to be responsible for the in crease of CBF after TRH administration.…”

Section: Discussionmentioning

confidence: 99%

Effect of Thyrotropin-Releasing Hormone on Cerebral Blood Flow in Conscious Rat

Kawakami

Mizusawa

Murakami

et al. 1989

J Cereb Blood Flow Metab

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Summary:The effect of thyrotropin-releasing hormone (TRH) was studied on local CBF (LCBF) in normal con scious rats. LCBF was measured by the auto radiographic [14C]iodoantipyrine method 5 min after TRH (5 mg/kg, i.v.) administration. TRH significantly in creased LCBF in 22 of 33 brain regions. This increase of LCBF exceeded 100% of the control values in the cere bral cortices, whereas there was no significant increase in

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Cerebral Blood Flow and Oxygen Consumption in Man

Abstract: I 52, I 53) ; the use of Krs5 (a p-emitting isotope of krypton) as the inert gas, increasing the number of blood samples, and sampling from both internal jugular

Cited by 1,829 publications

References 25 publications

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [¹⁸F] Fluorodeoxyglucose Method

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [¹⁸F] Fluorodeoxyglucose Method

Relationship Between the Ambulatory Arterial Stiffness Index and the Lower Limit of Cerebral Autoregulation During Cardiac Surgery

Effect of Thyrotropin-Releasing Hormone on Cerebral Blood Flow in Conscious Rat

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Cerebral Blood Flow and Oxygen Consumption in Man

Abstract: I 52, I 53) ; the use of Krs5 (a p-emitting isotope of krypton) as the inert gas, increasing the number of blood samples, and sampling from both internal jugular

Cited by 1,829 publications

References 25 publications

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [18F] Fluorodeoxyglucose Method

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [18F] Fluorodeoxyglucose Method

Relationship Between the Ambulatory Arterial Stiffness Index and the Lower Limit of Cerebral Autoregulation During Cardiac Surgery

Effect of Thyrotropin-Releasing Hormone on Cerebral Blood Flow in Conscious Rat

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Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [¹⁸F] Fluorodeoxyglucose Method

Effects of Human Aging on Patterns of Local Cerebral Glucose Utilization Determined by the [¹⁸F] Fluorodeoxyglucose Method