The Impact of Sevoflurane and Propofol Anesthesia on Cerebral Blood Flow in Pediatric Open Cardiac Surgery, a Comparative Randomized Study

Hyperlipidemia is a highly prevalent risk factor for coronary and cervical atherosclerosis and stroke. However, even in the absence of overt atherosclerosis, hyperlipidemia disrupts endothelial and smooth muscle function. We investigated the impact of hyperlipidemia on resting-brain perfusion, fundamental cerebrovascular reflexes, and dynamic perfusion defect during acute focal ischemia in hyperlipidemic apolipoprotein E knockout mice before the development of flow-limiting atherosclerotic stenoses. Despite elevated blood pressures, absolute resting cerebral blood flow was reduced by 20% in apolipoprotein E knockout compared with wild type when measured by [14C]-iodoamphetamine technique. Noninvasive, high spatiotemporal resolution laser speckle flow imaging revealed that the lower autoregulatory limit was elevated in apolipoprotein E knockout mice (60 vs. 40 mm Hg), and cortical hyperemic responses to hypercapnia and functional activation were attenuated by 30% and 64%, respectively. Distal middle cerebral artery occlusion caused significantly larger perfusion defects and infarct volumes in apolipoprotein E knockout compared with wild type. Cerebrovascular dysfunction showed a direct relationship to the duration of high-fat diet. These data suggest that hyperlipidemia disrupts cerebral blood flow regulation and diminishes collateral perfusion in acute stroke in the absence of hemodynamically significant atherosclerosis.

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Impact of blood pressure changes in cerebral blood perfusion of patients with ischemic Moyamoya disease evaluated by SPECT

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x20967458 ◽

2020 ◽

pp. 0271678X2096745

Author(s):

Zhao Liming ◽

Sun Weiliang ◽

Jia Jia ◽

Liang Hao ◽

Liu Yang ◽

...

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Moyamoya Disease ◽

Emission Computed Tomography ◽

Study Cohort ◽

Pressure Changes ◽

The Impact

Our aim was to determine the impact of targeted blood pressure modifications on cerebral blood flow in ischemic moyamoya disease patients assessed by single-photon emission computed tomography (SPECT). From March to September 2018, we prospectively collected data of 154 moyamoya disease patients and selected 40 patients with ischemic moyamoya disease. All patients underwent in-hospital blood pressure monitoring to determine the mean arterial pressure baseline values. The study cohort was subdivided into two subgroups: (1) Group A or relative high blood pressure (RHBP) with an induced mean arterial pressure 10–20% higher than baseline and (2) Group B or relative low blood pressure (RLBP) including patients with mean arterial pressure 10–20% lower than baseline. All patients underwent initial SPECT study on admission-day, and on the following day, every subgroup underwent a second SPECT study under their respective targeted blood pressure values. In general, RHBP patients showed an increment in perfusion of 10.13% (SD 2.94%), whereas RLBP patients showed a reduction of perfusion of 12.19% (SD 2.68%). Cerebral blood flow of moyamoya disease patients is susceptible to small blood pressure changes, and cerebral autoregulation might be affected due to short dynamic blood pressure modifications.

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Room B, 10/17/2000 9: 00 AM - 11: 00 AM (PS) Effect of Olprinone and Milrinone on Cerebral Blood Flow in Patients Following Cardiac Surgery

Anesthesiology ◽

10.1097/00000542-200009001-00154 ◽

2000 ◽

Vol 93 (3A) ◽

pp. A-154

Author(s):

Koji Goto ◽

Shigenori Yoshitake ◽

Koji Ito ◽

Akio Mizutani ◽

Tkayuki Noguchi

Keyword(s):

Blood Flow ◽

Cardiac Surgery ◽

Cerebral Blood Flow

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Pseudocontinuous Arterial Spin Labeling Reveals Dissociable Effects of Morphine and Alcohol on Regional Cerebral Blood Flow

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2010.234 ◽

2011 ◽

Vol 31 (5) ◽

pp. 1321-1333 ◽

Cited By ~ 33

Author(s):

Najmeh Khalili-Mahani ◽

Matthias JP van Osch ◽

Evelinda Baerends ◽

Roelof P Soeter ◽

Marieke de Kam ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Repeated Measures ◽

Arterial Spin Labeling ◽

Randomized Study ◽

Spin Labeling ◽

Statistical Testing ◽

Anterior Cingulate ◽

Double Blind ◽

Mixed Effect

We have examined sensitivity and specificity of pseudocontinuous arterial spin labeling (PCASL) to detect global and regional changes in cerebral blood flow (CBF) in response to two different psychoactive drugs. We tested alcohol and morphine in a placebo-controlled, double-blind randomized study in 12 healthy young men. Drugs were administered intravenously. Validated pharmacokinetic protocols achieved minimal intersubject and intrasubject variance in plasma drug concentration. Permutation-based statistical testing of a mixed effect repeated measures model revealed a widespread increase in absolute CBF because of both morphine and alcohol. Conjunction analysis revealed overlapping effects of morphine and alcohol on absolute CBF in the left anterior cingulate, right hippocampus, right insula, and left primary sensorimotor areas. Effects of morphine and alcohol on relative CBF (obtained from z-normalization of absolute CBF maps) were significantly different in the left putamen, left frontoparietal network, cerebellum, and the brainstem. Corroborating previous PET results, our findings suggest that PCASL is a promising tool for central nervous system drug research.

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Effects of Extreme Hemodilution during Cardiac Surgery on Cognitive Function in the Elderly

Anesthesiology ◽

10.1097/01.anes.0000281896.07256.71 ◽

2007 ◽

Vol 107 (4) ◽

pp. 577-584 ◽

Cited By ~ 56

Author(s):

Joseph P. Mathew ◽

G Burkhard Mackensen ◽

Barbara Phillips-Bute ◽

Mark Stafford-Smith ◽

Mihai V. Podgoreanu ◽

...

Keyword(s):

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Cognitive Function ◽

Adverse Events ◽

Older Patients ◽

Artery Bypass ◽

Randomized Study ◽

Multivariable Analysis ◽

Neurocognitive Deficits ◽

The Impact

Background Strategies for neuroprotection including hypothermia and hemodilution have been routinely practiced since the inception of cardiopulmonary bypass. Yet postoperative neurocognitive deficits that diminish the quality of life of cardiac surgery patients are frequent. Because there is uncertainty regarding the impact of hemodilution on perioperative organ function, the authors hypothesized that extreme hemodilution during cardiac surgery would increase the frequency and severity of postoperative neurocognitive deficits. Methods Patients undergoing coronary artery bypass grafting surgery were randomly assigned to either moderate hemodilution (hematocrit on cardiopulmonary bypass >or=27%) or profound hemodilution (hematocrit on cardiopulmonary bypass of 15-18%). Cognitive function was measured preoperatively and 6 weeks postoperatively. The effect of hemodilution on postoperative cognition was tested using multivariable modeling accounting for age, years of education, and baseline levels of cognition. Results After randomization of 108 patients, the trial was terminated by the Data Safety and Monitoring Board due to the significant occurrence of adverse events, which primarily involved pulmonary complications in the moderate hemodilution group. Multivariable analysis revealed an interaction between hemodilution and age wherein older patients in the profound hemodilution group experienced greater neurocognitive decline (P = 0.03). Conclusions In this prospective, randomized study of hemodilution during cardiac surgery with cardiopulmonary bypass in adults, the authors report an early termination of the study because of an increase in adverse events. They also observed greater neurocognitive impairment among older patients receiving extreme hemodilution.

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Voluntary running does not increase capillary blood flow but promotes neurogenesis and short-term memory in the APP/PS1 mouse model of Alzheimer’s disease

10.1101/2020.02.28.969840 ◽

2020 ◽

Cited By ~ 1

Author(s):

Kaja Falkenhain ◽

Nancy E. Ruiz-Uribe ◽

Mohammad Haft-Javaherian ◽

Muhammad Ali ◽

Pietro E. Michelucci ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Mouse Models ◽

Short Term Memory ◽

Wheel Running ◽

Memory Function ◽

Brain Inflammation ◽

Short Term ◽

Term Memory ◽

The Impact

ABSTRACTExercise exerts a beneficial effect on the major pathological and clinical symptoms associated with Alzheimer’ s disease in humans and mouse models of the disease. While numerous mechanisms for such benefits from exercise have been proposed, a clear understanding of the causal links remains elusive. Recent studies also suggest that cerebral blood flow in the brain of both Alzheimer’ s patients and mouse models of the disease is decreased and that the cognitive symptoms can be improved when blood flow is restored. We therefore hypothesized that the mitigating effect of exercise on the development and progression of Alzheimer’ s disease may be mediated through an increase in the otherwise reduced brain blood flow. To test this idea, we examined the impact of three months of voluntary wheel running in ∼1-year-old APP/PS1 mice on short-term memory function, brain inflammation, amyloid deposition, and cerebral blood flow. Our findings that exercise led to improved memory function, a trend toward reduced brain inflammation, markedly increased neurogenesis in the dentate gyrus, and no changes in amyloid-beta deposits are consistent with other reports on the impact of exercise on the progression of Alzheimer’ s related symptoms in mouse models. Notably, we did not observe any impact of wheel running on overall cortical blood flow nor on the incidence of non-flowing capillaries, a mechanism we recently identified as one contributing factor to cerebral blood flow deficits in mouse models of Alzheimer’ s disease. Overall, our results replicate previous findings that exercise is able to ameliorate certain aspects of Alzheimer’ s disease pathology, but show that this benefit does not appear to act through increases in cerebral blood flow.

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REGULATION OF CEREBRAL BLOOD FLOW IN HUMANS: PHYSIOLOGY AND CLINICAL IMPLICATIONS OF AUTOREGULATION

Physiological Reviews ◽

10.1152/physrev.00022.2020 ◽

2021 ◽

Author(s):

Jurgen A.H.R. Claassen ◽

Dick H.J. Thijssen ◽

Ronney B Panerai ◽

Frank M. Faraci

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Brain Function ◽

Vascular Reactivity ◽

Perfusion Pressure ◽

Cerebral Metabolism ◽

Blood Gases ◽

Clinical Implications ◽

Arterial Blood ◽

The Impact

Brain function critically depends on a close matching between metabolic demands, appropriate delivery of oxygen and nutrients, and removal of cellular waste. This matching requires continuous regulation of cerebral blood flow (CBF), which can be categorized into four broad topics: 1) autoregulation, which describes the response of the cerebrovasculature to changes in perfusion pressure, 2) vascular reactivity to vasoactive stimuli [including carbon dioxide (CO2)], 3) neurovascular coupling (NVC), i.e., the CBF response to local changes in neural activity (often standardized cognitive stimuli in humans), and 4) endothelium-dependent responses. This review focuses primarily on autoregulation and its clinical implications. To place autoregulation in a more precise context, and to better understand integrated approaches in the cerebral circulation, we also briefly address reactivity to CO2 and NVC. In addition to our focus on effects of perfusion pressure (or blood pressure), we describe the impact of select stimuli on regulation of CBF (i.e., arterial blood gases, cerebral metabolism, neural mechanisms, and specific vascular cells), the inter-relationships between these stimuli, and implications for regulation of CBF at the level of large arteries and the microcirculation. We review clinical implications of autoregulation in aging, hypertension, stroke, mild cognitive impairment, anesthesia, and dementias. Finally, we discuss autoregulation in the context of common daily physiological challenges, including changes in posture (e.g., orthostatic hypotension, syncope) and physical activity.

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