WordNet

cause to flow; "The artist flowed the washes on the paper"
the amount of fluid that flows in a given time (同)flow_rate, rate of flow
any uninterrupted stream or discharge
cover or swamp with water
the act of flowing or streaming; continuous progression (同)stream
the motion characteristic of fluids (liquids or gases) (同)flowing
move or progress freely as if in a stream; "The crowd flowed out of the stadium" (同)flux
be abundantly present; "The champagne flowed at the wedding"
smear with blood, as in a hunting initiation rite, where the face of a person is smeared with the blood of the kill
temperament or disposition; "a person of hot blood"
people viewed as members of a group; "we need more young blood in this organization"
the fluid (red in vertebrates) that is pumped through the body by the heart and contains plasma, blood cells, and platelets; "blood carries oxygen and nutrients to the tissues and carries away waste products"; "the ancients believed that blood was the sea
of or relating to the cerebrum or brain; "cerebral hemisphere"; "cerebral activity"
involving intelligence rather than emotions or instinct; "a cerebral approach to the problem"; "cerebral drama" (同)intellectual

PrepTutorEJDIC

《副詞巳句始を伴って》〈気体・液体・電気などが〉『流れる』 / 《副詞[句]を伴って》〈言葉・人々などず〉流れるように続く / 〈心・場所などが〉(…で)いっぱいになる,満ちあふれる《+『with』+『名』》 / 《副詞[句]を伴って》〈髪・服などが〉長く垂れる;風になびく / 〈潮が〉満ちる / (…から)生じる,発生する《+『from』+『名』》 / 〈C〉《単数形で》(気体・液体・電気などの)『流れ』《+『of』+『名』》 / 〈C〉《単数形で》(言葉・人などの)絶え間のない(よどみのない)流れ《+『of』+『名』》 / 〈C〉《単数形で》(…の)洪水,はんらん《+『of』+『名』》 / 〈U〉《the flow》満ち潮,上げ潮
『血』,『血』液 / 流血(bloodshed);殺人 / 気質,気性,血気,血潮 / 『血統』,血縁(kinship);生まれ,家柄;《the~》王家の血統 / (人種・出身国の)系 / 〈人〉‘に'初めての経験をさせる / 〈猟犬〉‘に'初めて獲物を血を味わわせる
大脳の,脳の / 頭脳的な,知的な
純血の,純種の / 《複合語を作って》「…の血(性質)を持った」の意を表す
流れる / 流ちょうな / ゆるやにかに垂れた

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/10/12 16:17:15」(JST)

wiki en

Cerebral blood flow (CBF) is the blood supply to the brain in a given period of time.^[1]^{[broken citation]} In an adult, CBF is typically 750 millilitres per minute or 15% of the cardiac output. This equates to an average perfusion of 50 to 54 millilitres of blood per 100 grams of brain tissue per minute.^[2]^[3]^[4] CBF is tightly regulated to meet the brain's metabolic demands.^[2]^[5] Too much blood (a condition known as hyperemia) can raise intracranial pressure (ICP), which can compress and damage delicate brain tissue. Too little blood flow (ischemia) results if blood flow to the brain is below 18 to 20 ml per 100 g per minute, and tissue death occurs if flow dips below 8 to 10 ml per 100 g per minute. In brain tissue, a biochemical cascade known as the ischemic cascade is triggered when the tissue becomes ischemic, potentially resulting in damage to and the death of brain cells. Medical professionals must take steps to maintain proper CBF in patients who have conditions like shock, stroke, cerebral edema, and traumatic brain injury.

Cerebral blood flow is determined by a number of factors, such as viscosity of blood, how dilated blood vessels are, and the net pressure of the flow of blood into the brain, known as cerebral perfusion pressure, which is determined by the body's blood pressure. Cerebral blood vessels are able to change the flow of blood through them by altering their diameters in a process called autoregulation; they constrict when systemic blood pressure is raised and dilate when it is lowered.^[6] Arterioles also constrict and dilate in response to different chemical concentrations. For example, they dilate in response to higher levels of carbon dioxide in the blood and constrict to lower levels of carbon dioxide.^[6]

For example, assuming a person with an arterial partial pressure of carbon dioxide (PaCO2) of 40 mmHg (normal range of 38 - 42 mmHg)^[7] and a CBF of 50 ml per 100g per min. If the PaCO2 dips to 30 mmHg, this represents a 10 mmHg decrease from the initial value of PaCO2. Consequently, the CBF decreases by 1ml per 100g per min for each 1mmHg decrease in PaCO2, resulting in a new CBF of 40ml per 100g of brain tissue per minute. In fact, for each 1 mmHg increase or decrease in PaCO2, between the range of 20–60 mmHg, there is a corresponding CBF change in the same direction of approximately 1–2 ml/100g/min, or 2–5% of the CBF value.^[8] This is why small alterations in respiration pattern can cause significant changes in global CBF, specially through PaCO2 variations.^[8]

CBF is equal to the cerebral perfusion pressure (CPP) divided by the cerebrovascular resistance (CVR):^[9]

CBF = CPP / CVR

Control of CBF is considered in terms of the factors affecting CPP and the factors affecting CVR. CVR is controlled by four major mechanisms:

Metabolic control (or 'metabolic autoregulation')
Pressure autoregulation
Chemical control (by arterial pCO₂ and pO₂)
Neural control

Functional magnetic resonance imaging and positron emission tomography are neuroimaging techniques that can be used to measure CBF. These techniques are also used to measure regional CBF (rCBF) within a specific brain region. rCBF at one location can be measured over time by thermal diffusion^[10]

Role of intracranial pressure

Increased intracranial pressure (ICP) causes decreased blood perfusion of brain cells by mainly two mechanisms:

Increased ICP constitutes an increased interstitial hydrostatic pressure that, in turn, causes a decreased driving force for capillary filtration from intracerebral blood vessels.
Increased ICP compresses cerebral arteries, causing increased cerebrovascular resistance (CVR).

References

^ Tolias C and Sgouros S. 2006. "Initial Evaluation and Management of CNS Injury." Emedicine.com. Accessed January 4, 2007.
^ ^a ^b Orlando Regional Healthcare, Education and Development. 2004. "Overview of Adult Traumatic Brain Injuries." Accessed 2008-01-16.
^ Shepherd S. 2004. "Head Trauma." Emedicine.com. Shepherd S. 2004. "Head Trauma." Emedicine.com. Accessed January 4, 2007.
^ Walters, FJM. 1998. "Intracranial Pressure and Cerebral Blood Flow." Physiology. Issue 8, Article 4. Accessed January 4, 2007.
^ Singh J and Stock A. 2006. "Head Trauma." Emedicine.com. Accessed January 4, 2007.
^ ^a ^b Kandel E.R., Schwartz, J.H., Jessell, T.M. 2000. Principles of Neural Science, 4th ed., McGraw-Hill, New York. p.1305
^ Hadjiliadis D, Zieve D, Ogilvie I. Blood Gases. Medline Plus. 06/06/2015.
^ ^a ^b Giardino ND, Friedman SD, Dager SR. Anxiety, respiration, and cerebral blood flow: implications for functional brain imaging. Compr Psychiatry 2007;48:103–112. Accessed 6/6/2015.
^ AnaesthesiaUK. 2007. Cerebral Blood Flow (CBF). Accessed 2007-10-16.
^ P. Vajkoczy, H. Roth, P. Horn, T. Lucke, C. Thome, U. Hubner, G. T. Martin, C. Zappletal, E. Klar, L. Schilling, and P. Schmiedek, “Continuous monitoring of regional cerebral blood flow: experimental and clinical validation of a novel thermal diffusion microprobe,” J. Neurosurg., vol. 93, no. 2, pp. 265–274, Aug. 2000. [1]

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 成人における頭蓋内圧亢進の評価およびマネージメント evaluation and management of elevated intracranial pressure in adults
2. 虚血性脳卒中の病態生理 pathophysiology of ischemic stroke
3. 脳死の診断 diagnosis of brain death
4. 小児における頭蓋内圧亢進（ICP） elevated intracranial pressure icp in children
5. 頸動脈内膜剥離術および頸動脈ステント留置術の麻酔 anesthesia for carotid endarterectomy and carotid stenting

English Journal

The capillary dysfunction hypothesis of Alzheimer's disease.

Ostergaard L, Aamand R, Gutiérrez-Jiménez E, Ho YC, Blicher JU, Madsen SM, Nagenthiraja K, Dalby RB, Drasbek KR, Møller A, Brændgaard H, Mouridsen K, Jespersen SN, Jensen MS, West MJ.SourceCenter of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark; Department of Neuroradiology, Aarhus University Hospital, Aarhus, Denmark. Electronic address: leif@cfin.dk.
Neurobiology of aging.Neurobiol Aging.2013 Apr;34(4):1018-31. doi: 10.1016/j.neurobiolaging.2012.09.011. Epub 2012 Oct 18.
It is widely accepted that hypoperfusion and changes in capillary morphology are involved in the etiopathogenesis of Alzheimer's disease (AD). This is difficult to reconcile with the hyperperfusion observed in young high-risk subjects. Differences in the way cerebral blood flow (CBF) is coupled with
PMID 23084084

On-line blood viscosity monitoring in vivo with a central venous catheter, using electrical impedance technique.

Pop GA, Bisschops LL, Iliev B, Struijk PC, Hoeven JG, Hoedemaekers CW.SourceDepartment of Cardiology, Radboud University Nijmegen Medical Centre, P.O Box 9101, 6500 HB Nijmegen, The Netherlands. Electronic address: G.Pop@cardio.umcn.nl.
Biosensors & bioelectronics.Biosens Bioelectron.2013 Mar 15;41:595-601. doi: 10.1016/j.bios.2012.09.033. Epub 2012 Oct 4.
Blood viscosity is an important determinant of microvascular hemodynamics and also reflects systemic inflammation. Viscosity of blood strongly depends on the shear rate and can be characterized by a two parameter power-law model. Other major determinants of blood viscosity are hematocrit, level of i
PMID 23089327

Effects of mild chronic cerebral hypoperfusion and early amyloid pathology on spatial learning and the cellular innate immune response in mice.

Pimentel-Coelho PM, Michaud JP, Rivest S.SourceLaboratory of Endocrinology and Genomics, CHUQ (CHUL) Research Center and Department of Molecular Medicine, Faculty of Medicine, Laval University, Quebec, Canada.
Neurobiology of aging.Neurobiol Aging.2013 Mar;34(3):679-93. doi: 10.1016/j.neurobiolaging.2012.06.025. Epub 2012 Jul 20.
Understanding the contribution of cerebrovascular factors in the progression of cognitive decline in Alzheimer's disease (AD) is a key step for the development of preventive therapies. Among these factors, chronic cerebral hypoperfusion is an early component of AD pathogenesis that can predict the p
PMID 22819135

Japanese Journal

EFFECT OF LIDOCAINE ON DYNAMIC CHANGES IN CORTICAL REDUCED NICOTINAMIDE ADENINE DINUCLEOTIDE FLUORESCENCE DURING TRANSIENT FOCAL CEREBRAL ISCHEMIA IN RATS

Naito H.,Takeda Y.,Danura T.,Kass I. S.,Morita K.
Neuroscience 235, 59-69, 2013-04-03
… Rats were subjected to 90 min of focal ischemia by occluding the left middle cerebral and both common carotid arteries. … Following the initiation of ischemia, an area of high-intensity NADH fluorescence rapidly developed in the middle cerebral artery territory in both groups and the DC potential in this area showed ischemic depolarization. … The blood flow in the marginal zone of both groups showed a similar decrease. …
NAID 120005324794

O-27 Is aerobic exercise capacity related to cerebral blood flow velocity in postmenopausal women?(The Proceedings of the 20th Annual Meetings of Japan Society of Exercise and Sports Physiology July 28・29,(Tsukuba))

AKAZAWA Nobuhiko,CHOI Youngju,MIYAKI Asako,AJISAKA Ryuichi,MAEDA Seiji
Advances in exercise and sports physiology 18(4), 95, 2013-02-00
NAID 110009592342

An Impairment of Recognizing Emotional Facial Expressions in Parkinson's Disease

Nakajima Hideki,Tsujino Akira,Doi Hirokazu,Tateishi Yohei,Motomura Masakatsu,Shinohara Kazuyuki,Satoh Akira,Tsujihata Mitsuhiro,Kawakami Atsushi
Acta medica Nagasakiensia 57(3), 69-77, 2013-02-00
… we demonstrated that PD patients displayed a prominent degree of hypoperfusion in the occipital lobe, while also demonstrating an impairment in recognizing the facial emotions for both anger and happiness.The ability to recognize the facial emotions for happiness has been shown to be closely associated with a decreased cerebral blood flow (CBF) in the right occipital lobe.In PD patients, an impairment in recognizing emotional facial expressions might be partially due to an occipital cortical …
NAID 110009552089

Related Pictures

★リンクテーブル★

リンク元	「脳血流」「脳血流量」「CBF」
拡張検索	「regional cerebral blood flow」
関連記事	「flow」「cerebral」「blood」

「脳血流」

　　[★]

英: cerebral blood flow
関: 脳血流量

麻酔薬、鎮痛薬と脳血流

静脈麻酔薬#静脈麻酔薬の脳への作用および吸入麻酔薬#麻酔薬と脳に及ぼす影響より。文献的な裏付けなし。

分類	投与経路	薬剤名	脳血流	脳代謝量
麻酔薬	静脈 (静脈麻酔薬)	プロポフォール	↓↓	↓
		バルビツレート	↓	↓
		ミダゾラム	↓	↓
		ケタミン	↑↑	↑
	吸入 (吸入麻酔薬)	亜酸化窒素	↑	↑
		セボフルラン	↑	↓
		イソフルラン	↑	↓
		ハロタン	↑↑	↓
鎮痛薬	静脈	フェンタニル	↓	↓
鎮痛薬	静脈	レミフェンタニル	↓	↓

吸入麻酔薬では脳血管拡張作用により脳血流が増加

静脈麻酔薬の興奮性麻酔薬では脳神経活動亢進、酸素消費量増大など代謝の亢進のために脳血管拡張を来たし、脳血流増加 (SAN.45)

静脈麻酔薬の抑制性麻酔薬では脳神経活動低下、酸素消費量低下など代謝の低下のために脳血管収縮を来たし、脳血流低下 (SAN.45)

SAN.291改変

分類	薬剤名	脳血流	脳酸素消費量
吸入麻酔薬	亜酸化窒素	↑↑	↑
	ハロタン	↑↑	↑
	イソフルラン	↑	↓↓
	セボフルラン	→↑	↓↓
静脈麻酔薬	チオペンタール	↓↓	↓↓
	プロポフォール	↓↓	↓
	フェンタニル	→	→
	ケタミン	↑↑	↑