Vascular PhysiologyVascular Physiology

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Structure of Blood Vessels WallsStructure of Blood Vessels Walls

Three layers:Three layers:TunicaTunica interaintera:Inner most layer, endo-:Inner most layer, endo-thelium (simple squamous) & some larger vessels thelium (simple squamous) & some larger vessels have subendothelium (loose CT & BM), have subendothelium (loose CT & BM), Tunica Tunica mediamedia: Middle layer, circularly arranged smooth : Middle layer, circularly arranged smooth muscle, chemical & nervous control of deg. of cont-muscle, chemical & nervous control of deg. of cont-raction (sym. NS) & change in dia. (VC & VD), raction (sym. NS) & change in dia. (VC & VD), Tunica externaTunica externa: Made of collagen fibers, function : Made of collagen fibers, function (protection, reinforcement & anchor to surround. (protection, reinforcement & anchor to surround. tissue),accessory tissues(nerve fi., lymphatic v., ela-tissue),accessory tissues(nerve fi., lymphatic v., ela-stic network& tiny Bdv within layer-vasa vasorum)stic network& tiny Bdv within layer-vasa vasorum)

Arterial SystemArterial System

Classification based on size and functionClassification based on size and function1. Elastic (conducting) arteries1. Elastic (conducting) arteries: Thick-walled, near : Thick-walled, near heart, largest diameter, more elastic, large lumen heart, largest diameter, more elastic, large lumen (dampen BP changes associated (dampen BP changes associated withwith Ht Ht contraction , passive accommodation results in contraction , passive accommodation results in smooth flow of blood ‘1.0 - 2.5 cm’smooth flow of blood ‘1.0 - 2.5 cm’

2. Muscular arteries-distributing arteries2. Muscular arteries-distributing arteries: Distal to : Distal to elastic arteries, deliver Bd to specific organs, thick elastic arteries, deliver Bd to specific organs, thick media layer (more smooth muscle) & 0.3 - 1.0 cmmedia layer (more smooth muscle) & 0.3 - 1.0 cm3. Arterioles3. Arterioles: Determine flow into capillary beds, : Determine flow into capillary beds, mostly smooth muscle & 10 µm - 0.3 cmmostly smooth muscle & 10 µm - 0.3 cm4. Capillaries4. Capillaries: Smallest blood vessels (8 - 10 µm), : Smallest blood vessels (8 - 10 µm), tunica interna only & exchange of materialstunica interna only & exchange of materials

Types of capillaryTypes of capillary1. 1. ContinuousContinuous: Uninterrupted endothelial cells, : Uninterrupted endothelial cells, incomplete tight junctions (intercellular clefts)incomplete tight junctions (intercellular clefts)2. 2. FenestratedFenestrated: Endothelial cells have oval pores : Endothelial cells have oval pores (fenestrations) to permit greater permeability(fenestrations) to permit greater permeability3. 3. SinusoidalSinusoidal: Modified, leaky capillaries (large : Modified, leaky capillaries (large molecules can pass through)molecules can pass through)

Capillary beds Capillary beds 1. Capillaries act as networks-capillary beds1. Capillaries act as networks-capillary beds2. Microcirculation: Arteriole to venule2. Microcirculation: Arteriole to venule3. Parts of a capillary bed:3. Parts of a capillary bed:a. Vascular shunt: Connects arteriole with venulea. Vascular shunt: Connects arteriole with venuleb. True capillariesb. True capillaries

Sequence of Bd movement through capillary bedSequence of Bd movement through capillary bed1. Terminal arteriole1. Terminal arteriole2. Metateriole: True capillaries branch off (Pre-2. Metateriole: True capillaries branch off (Pre-capillary sphincter controls Bd flow into capillarycapillary sphincter controls Bd flow into capillary3. Thoroughfare channel: Capillaries rejoin3. Thoroughfare channel: Capillaries rejoin4. Post-capillary venule4. Post-capillary venule

Venous SystemVenous System

Types of vesselsTypes of vessels1. Venules: 8 - 100 µm, properties vary with size 1. Venules: 8 - 100 µm, properties vary with size (little muscle & thin externa)(little muscle & thin externa)2. Veins: Formed from venules, thinner walls and 2. Veins: Formed from venules, thinner walls and less muscle than arteries, little muscle in medialess muscle than arteries, little muscle in media(mostly elastin) & externa is thickest wall layer(mostly elastin) & externa is thickest wall layer

Capacitance vesselsCapacitance vessels1. Veins act as reservoirs: Large lumens & low BP 1. Veins act as reservoirs: Large lumens & low BP allows walls to thinallows walls to thin2. Venous valves: Prevent backflow (folds of 2. Venous valves: Prevent backflow (folds of interna)interna)

Physiology of CirculationPhysiology of Circulation

1. Blood flow-volume per unit time (ml/min)1. Blood flow-volume per unit time (ml/min)2. Blood pressure-force per unit area (mm Hg)2. Blood pressure-force per unit area (mm Hg)3. Resistance-opposition to flow; generally encoun-3. Resistance-opposition to flow; generally encoun-tered in the systemic circuit (peripheral resistance: tered in the systemic circuit (peripheral resistance: PR): Sources of resistance (Bd PR): Sources of resistance (Bd viscosityviscosity “thickness “thickness related to formed elements”, related to formed elements”, total bv lengthtotal bv length ‘longer ‘longer vessel greater resistance’ & vessel greater resistance’ & bv diabv dia. ‘flow inversely . ‘flow inversely related to dia.; larger dia. less resistance (1/rrelated to dia.; larger dia. less resistance (1/r44)’.)’.In humans, dia. is the greatest source of resistanceIn humans, dia. is the greatest source of resistanceBlood Flow (F) = ∆P/PRBlood Flow (F) = ∆P/PR

Systemic Blood PressureSystemic Blood Pressure

BackgroundBackground1. Heart pumping generates blood flow1. Heart pumping generates blood flow2. Pr. results when flow opposed by resistance2. Pr. results when flow opposed by resistance3. Bd flows along a pr. gradient from higher to 3. Bd flows along a pr. gradient from higher to lower pr. (highest in aorta & lowest in rt atrium)lower pr. (highest in aorta & lowest in rt atrium)

Arterial blood pressure: Arterial blood pressure: 1. Factors affecting arterial pr.: Stretching of 1. Factors affecting arterial pr.: Stretching of arteries near Ht (compliance & distensibility) & arteries near Ht (compliance & distensibility) & vol. Bd forced into arteries near Htvol. Bd forced into arteries near Ht2. Changes associated with sys.: Aorta is stretched 2. Changes associated with sys.: Aorta is stretched by Bd leaving lt ven. (kinetic energy) & Bd moves by Bd leaving lt ven. (kinetic energy) & Bd moves toward periphery because peripheral Pr. is lower toward periphery because peripheral Pr. is lower than aortic Pr. (SP: 120 mm Hg)than aortic Pr. (SP: 120 mm Hg)

3. Changes associated with dias.: Semilunar valve 3. Changes associated with dias.: Semilunar valve closes, aorta recoils & Pr. is maintained by closes, aorta recoils & Pr. is maintained by reducing volume (DP: 70 - 80 mm Hg)reducing volume (DP: 70 - 80 mm Hg)4. Pulse pressure (PP): SP minus DP4. Pulse pressure (PP): SP minus DP5. Mean arterial pressure (MAP)=DP+ 1/3 PP5. Mean arterial pressure (MAP)=DP+ 1/3 PP

Capillary blood pressureCapillary blood pressure1. 40 mm Hg entering1. 40 mm Hg entering2. 20 mm Hg exiting2. 20 mm Hg exitingVenous blood pressureVenous blood pressure1. Relatively steady throughout cardiac cycle1. Relatively steady throughout cardiac cycle2. Gradient from venules to vena cava (20 mm HG 2. Gradient from venules to vena cava (20 mm HG ‘60 from aorta to arterioles’)‘60 from aorta to arterioles’)

Venous return: Venous pressure is too low for Venous return: Venous pressure is too low for adequate return, need functional modifications: adequate return, need functional modifications: a. Respiratory pump (abdominal pr. squeeze local a. Respiratory pump (abdominal pr. squeeze local veins, backflow is prevented by valves, Bd is forced veins, backflow is prevented by valves, Bd is forced toward the Ht, chest cavity pr. Decreases, thoracic toward the Ht, chest cavity pr. Decreases, thoracic veins expand & Bd enters rt atriumveins expand & Bd enters rt atriumb. Muscular pump ‘more important’ (contraction b. Muscular pump ‘more important’ (contraction of skeletal muscle surrounding veins compress of skeletal muscle surrounding veins compress vein, backflow is prevented by valves so Bd moves vein, backflow is prevented by valves so Bd moves in direction of Htin direction of Ht

Regulation of Blood PressureRegulation of Blood Pressure

Factors influences blood pressureFactors influences blood pressure1. Cardiac output1. Cardiac output2. Peripheral resistance2. Peripheral resistance3. Blood volume3. Blood volume

BP = CO X PRBP = CO X PR1. Cardiac output is directly related to Bd vol.1. Cardiac output is directly related to Bd vol.2. BP is directly related to CO, BV and PR2. BP is directly related to CO, BV and PRCO = Stroke volume X HR CO = Stroke volume X HR

Factors that enhance COFactors that enhance CO1. Reduce parasym. control (HR increases)1. Reduce parasym. control (HR increases)2. Increase sym. Activity: Increases contractility of 2. Increase sym. Activity: Increases contractility of Ht (reduces ESV & increases SV) & releases Epi Ht (reduces ESV & increases SV) & releases Epi into Bd stream from adrenal med. (increases HR)into Bd stream from adrenal med. (increases HR)3. Increase activity of resp. & muscular pumps: 3. Increase activity of resp. & muscular pumps: Increases venous return (increases EDV & SV)Increases venous return (increases EDV & SV)

Neural control of blood pressureNeural control of blood pressure1.1. Short-term mechanisms Short-term mechanisms2.2. Nervous control of peripheral resistance Nervous control of peripheral resistancea. Alter blood distributiona. Alter blood distributionb. Alter blood vessel diameterb. Alter blood vessel diameter3.3. Vasomotor center Vasomotor center

a. Regulation of blood vessel diametera. Regulation of blood vessel diameterb. Vasomotor fibers (sym. Efferents, innervate sm b. Vasomotor fibers (sym. Efferents, innervate sm of blood v.‘primarily arterioles’& release NE: VC)of blood v.‘primarily arterioles’& release NE: VC)c. Vasomotor tone (tonic vasoconstriction)c. Vasomotor tone (tonic vasoconstriction)

4.4. Baroreceptors: Baroreceptors: a. Detect changes in art. BP: Pr. sensitive mechano-a. Detect changes in art. BP: Pr. sensitive mechano-receptors when BP rises, receptors are stretchedreceptors when BP rises, receptors are stretchedb. Located in carotid sinuses, aortic arch & walls of b. Located in carotid sinuses, aortic arch & walls of all large vesselsall large vesselsc. Stretching increase signal to vasomotor center: c. Stretching increase signal to vasomotor center: Inhibits vasomotor center causes VDInhibits vasomotor center causes VDd. Arteriole dilation reduces peripheral resistanced. Arteriole dilation reduces peripheral resistance

e. Venodilation shifts Bd to venous reservoirs: e. Venodilation shifts Bd to venous reservoirs: Venous return decreases & CO declinesVenous return decreases & CO declinesf. Baroreceptors also send efferent signals to card. f. Baroreceptors also send efferent signals to card. centers in medulla: Inhibit sym. NS, stimulate centers in medulla: Inhibit sym. NS, stimulate parasym. NS to decrease HR & contractile forceparasym. NS to decrease HR & contractile forceg. Respond to acute changes in BP: Carotid sinus g. Respond to acute changes in BP: Carotid sinus reflex protects Bd supply to brain & aortic reflex reflex protects Bd supply to brain & aortic reflex maintains supply to systemic circuitmaintains supply to systemic circuit

5.5. Chemoreceptors Chemoreceptors a. Respond to changes in O2 and CO2 a. Respond to changes in O2 and CO2 concentrations and pHconcentrations and pHb. Located in carotid and aortic arch and carotid b. Located in carotid and aortic arch and carotid sinussinusc. Primarily involved in control of respiratory rate c. Primarily involved in control of respiratory rate and depthand depth

Chemical control of blood pressureChemical control of blood pressure1. Short-term1. Short-term2. Levels of O2 and CO22. Levels of O2 and CO23. Blood-borne chemicals3. Blood-borne chemicals

a.a. Adrenal medulla hormones Adrenal medulla hormones i. NE and EPI (nicotine is a monoamine agonist)i. NE and EPI (nicotine is a monoamine agonist) ii. NE is a vasoconstrictorii. NE is a vasoconstrictor iii. EPI increase CO by increasing contractilityiii. EPI increase CO by increasing contractilityb.b. Atrial natriuretic peptide (ANP) Atrial natriuretic peptide (ANP) i. Atrial peptide hormonei. Atrial peptide hormone ii. Reduces BP by antagonizing aldosteroneii. Reduces BP by antagonizing aldosterone iii. Increases water excretion from kidneyiii. Increases water excretion from kidney

c.c. Antidiuretic hormone (ADH) Antidiuretic hormone (ADH) i. Posterior pituitary hormonei. Posterior pituitary hormone ii. Increases BP by increasing water reabsorptionii. Increases BP by increasing water reabsorption iii. At high conc., causes vasoconstrictioniii. At high conc., causes vasoconstriction

d.d. Angiotensin II: Mediated by release of renin by Angiotensin II: Mediated by release of renin by JGA of kidney tubule. When Bd amount entering JGA of kidney tubule. When Bd amount entering kidney tubule is too low; renin releases & catalyzes kidney tubule is too low; renin releases & catalyzes the conversion of angiotensinogen to angiotensin II the conversion of angiotensinogen to angiotensin II which II causes VC of systemic arterioles & which II causes VC of systemic arterioles & increases BP. Angiotensin II also causes release of increases BP. Angiotensin II also causes release of aldosterone from adrenal cortex which increases aldosterone from adrenal cortex which increases absorption of water by kidney tubulesabsorption of water by kidney tubules

e.e. Endothelium-derived factors: Endothelin (VC), Endothelium-derived factors: Endothelin (VC), prostaglandin-derived growth factor“PDGF” (VC)prostaglandin-derived growth factor“PDGF” (VC), nitrous oxide “NO” (fast acting local VD), nitrous oxide “NO” (fast acting local VD)f.f. Inflammatory chemicals (VD): Histamine, etc. Inflammatory chemicals (VD): Histamine, etc. (increase capillary permeability)(increase capillary permeability)g.g. Alcohol: Reduces BP, inhibits ADH release Alcohol: Reduces BP, inhibits ADH release (increases loss of water in urine) & increases VD (increases loss of water in urine) & increases VD (skin) by depressing vasomotor center(skin) by depressing vasomotor center

Renal regulation of blood pressureRenal regulation of blood pressure1.1. Long-term mechanisms for BP regulation Long-term mechanisms for BP regulation2.2. Kidney controls Bd vol. by regulating water loss Kidney controls Bd vol. by regulating water loss3.3. Blood volume affects CO via: a. Venous pressure Blood volume affects CO via: a. Venous pressureb. Venous return, c. EDV & d. Stroke volume b. Venous return, c. EDV & d. Stroke volume 4.4. BP change parallels change in Bd vol.: a. High BP change parallels change in Bd vol.: a. High vol. increases BP (kidney responds by eliminating vol. increases BP (kidney responds by eliminating water to reduce vol.) & b. Low vol. decreases BP (water to reduce vol.) & b. Low vol. decreases BP (kidney reabsorbs water to increase vol.) kidney reabsorbs water to increase vol.)

5.5. Direct action of the kidney Direct action of the kidneya. Alters rate of fluid filtration from Bd stream to a. Alters rate of fluid filtration from Bd stream to kidney tubules (High BP increases filtrate entering kidney tubules (High BP increases filtrate entering tubules greater than can be processed, fluid leaves tubules greater than can be processed, fluid leaves body as urine, Bd vol. decreases & therefore BPbody as urine, Bd vol. decreases & therefore BPb. Indirect renal mechanisms (renin-angiotensin b. Indirect renal mechanisms (renin-angiotensin mechanism, aldosterone also cause release of ADH mechanism, aldosterone also cause release of ADH which promotes water reabsorption by kidneywhich promotes water reabsorption by kidney

Tissue PerfusionTissue Perfusion

Blood flow is precisely distributed to body tissueBlood flow is precisely distributed to body tissue: : 1. At rest1. At resta. Brain: 13%a. Brain: 13%b. Heart 4%b. Heart 4%c. Kidney: 20%c. Kidney: 20%d. Abdominal organs: 24%d. Abdominal organs: 24%2. During exercise:2. During exercise:a. Skin, muscles and heart increasea. Skin, muscles and heart increaseb. Other tissues either remain same or decreaseb. Other tissues either remain same or decrease

Blood flow velocityBlood flow velocity 1. Inversely proportionate to cross-sectional area of 1. Inversely proportionate to cross-sectional area of bv to be filled: It is fastest in vessels with smallest bv to be filled: It is fastest in vessels with smallest cross-sectional area “aorta has a cross-sectional cross-sectional area “aorta has a cross-sectional area (2.5 cm2) & an average velocity of 40-50 cm/s, area (2.5 cm2) & an average velocity of 40-50 cm/s, capillaries have a total cross-sectional area of 4500 capillaries have a total cross-sectional area of 4500 cm2 and a very slow flow (0.03 cm/s)”cm2 and a very slow flow (0.03 cm/s)”

Blood flow through individual organs is intrinsical-Blood flow through individual organs is intrinsical-ly controlled (i.e., autoregulation)ly controlled (i.e., autoregulation): Diameter of : Diameter of arterioles feeding a given organ is controlled by itarterioles feeding a given organ is controlled by itIntrinsic control mechanismsIntrinsic control mechanisms1. Metabolic controls: Levels of nutrients, particul-1. Metabolic controls: Levels of nutrients, particul-arly oxygen, act as autoregulation stimuliarly oxygen, act as autoregulation stimuli2. Myogenic controls: Excessive or inadequate BP 2. Myogenic controls: Excessive or inadequate BP can damage or cause death of an organ, such BP can damage or cause death of an organ, such BP changes stimulate myogenic responseschanges stimulate myogenic responses

Capillary DynamicsCapillary Dynamics

Gases & nutrients diffuse from capillary to inter-Gases & nutrients diffuse from capillary to inter-stitial fluid: stitial fluid: Water-soluble solutes pass through Water-soluble solutes pass through clefts & fenestrations while lipid-soluble diffuse clefts & fenestrations while lipid-soluble diffuse through PM of capillary epithelial cellsthrough PM of capillary epithelial cellsForces responsible for direction & amount of fluid Forces responsible for direction & amount of fluid crossing capillary walls: crossing capillary walls: Hydrostatic & osmotic Hydrostatic & osmotic Pressures (forces oppose)Pressures (forces oppose)

Hydrostatic pressure (HP)Hydrostatic pressure (HP): Force exerted by fluid : Force exerted by fluid against vessel wall. In capillary bed HP is the same against vessel wall. In capillary bed HP is the same as capillary BP that forces fluid through capillary as capillary BP that forces fluid through capillary wall: Greater at arterial end (35 mm Hg) & lower wall: Greater at arterial end (35 mm Hg) & lower at venous end (17 mmHg). HPc is opposed by inter-at venous end (17 mmHg). HPc is opposed by inter-stitial fluid HP (Hpif) which is assumed to be zero stitial fluid HP (Hpif) which is assumed to be zero (interstitial fluid is withdrawn by lymphatic tissue). (interstitial fluid is withdrawn by lymphatic tissue). Net effective HP is equal to HPc (=HPc - Hpif)Net effective HP is equal to HPc (=HPc - Hpif)

Osmotic pressureOsmotic pressure: Net movement of water from an : Net movement of water from an area of low to high solute conc. which is relatively area of low to high solute conc. which is relatively high in capillary Bd (high concentration of plasma high in capillary Bd (high concentration of plasma proteins). Capillary colloid osmotic pr. (OPc) = 26 proteins). Capillary colloid osmotic pr. (OPc) = 26 mm Hg. Interstitial osmotic pressure (OPif) = 0.1 - mm Hg. Interstitial osmotic pressure (OPif) = 0.1 - 5 mm Hg. Net osmotic pressure ≈ 25 mm Hg5 mm Hg. Net osmotic pressure ≈ 25 mm Hg

Net filtration pressure (NFP)Net filtration pressure (NFP): Reflects interaction : Reflects interaction between hydrostatic & osmotic pressuresbetween hydrostatic & osmotic pressuresAt arterial end: NFP = (HPc - Hpif) - (OPc - OPif)At arterial end: NFP = (HPc - Hpif) - (OPc - OPif)= 35 - 25 = 10 mm Hg= 35 - 25 = 10 mm HgAt Venous end: NFP = (HPc - Hpif) - (OPc - OPif)At Venous end: NFP = (HPc - Hpif) - (OPc - OPif)= 17 - 25 = -8 mm Hg= 17 - 25 = -8 mm Hg

Pulmonary CirculationPulmonary Circulation

Pulmonary trunk, rt. and lt. pulmonary arteries, Pulmonary trunk, rt. and lt. pulmonary arteries, lobar arteries (3 in rt lung & 2 in lt), arterioles, lobar arteries (3 in rt lung & 2 in lt), arterioles, capillaries, venules, pulmonary veins (2 per lung), capillaries, venules, pulmonary veins (2 per lung), which drain into left atriumwhich drain into left atrium

Overview of Systemic CirculationOverview of Systemic Circulation

Aorta and Major Arteries of Systemic Circulation Aorta and Major Arteries of Systemic Circulation Aortic archAortic arch 1.1. Coronary arteries Coronary arteries2.2. Brachiocephalic: Brachiocephalic: a.a. R. common carotid ( R. common carotid (i.i. R. R. internal carotid & internal carotid & ii.ii. R. external carotid) & R. external carotid) & b.b. R. R. subclavian (subclavian (i.i. R. vertebral & R. vertebral & ii.ii. R. axillary) R. axillary)3.3. L. common carotid: L. common carotid: a.a. L. internal carotid & L. internal carotid & b.b. L. L. external carotidexternal carotid4.4. L. subclavian: L. subclavian: a.a. L. vertebral & L. vertebral & b.b. L. axillary L. axillary

Thoracic aortaThoracic aorta (above the diaphragm) (above the diaphragm) 1. Parietal branches1. Parietal branches2. Visceral branches2. Visceral branchesAbdominal aortaAbdominal aorta (below diaphragm) (below diaphragm)1. Parietal branches1. Parietal branches2. Visceral branches2. Visceral branches3. R. common iliac3. R. common iliac4. L. common iliac4. L. common iliac

Arteries of Head and NeckArteries of Head and Neck

R. BrachiocephalicR. Brachiocephalic artery branches off aortic arch artery branches off aortic arch1. R. subclavian artery 1. R. subclavian artery 2. R. vertebral artery 2. R. vertebral artery 3. Basilar artery (R+L vertebrals)3. Basilar artery (R+L vertebrals)4. R. and L. posterior cerebral arteries: Supply 4. R. and L. posterior cerebral arteries: Supply occipital and inferior temporal lobes of brainoccipital and inferior temporal lobes of brain

R. common carotid arteryR. common carotid artery: (off R brachiocephalic) : (off R brachiocephalic) R. external & internal carotid arteriesR. external & internal carotid arteriesFrom external carotid arteryFrom external carotid artery::1. Superior thyroid:Supplies thyroid & larynx1. Superior thyroid:Supplies thyroid & larynx2. Lingual: Supplies tongue2. Lingual: Supplies tongue3. Facial: Supplies skin & muscles of anterior face3. Facial: Supplies skin & muscles of anterior face4. Occipital: Supplies posterior scalp4. Occipital: Supplies posterior scalp5. Maxillary: Supplies upper & lower jaw5. Maxillary: Supplies upper & lower jaw6. Superficial temporal: Supplies most of scalp6. Superficial temporal: Supplies most of scalp

R. Internal carotidR. Internal carotid::1. Enters the skull and services the brain1. Enters the skull and services the brain2. Opthalmic: eyes, orbits, forehead & nose2. Opthalmic: eyes, orbits, forehead & nose3. R. internal carotid divides to form3. R. internal carotid divides to forma. R. ant. cerebral artery: Medial surface of braina. R. ant. cerebral artery: Medial surface of brainb. R. middle cerebral artery: Lateral parts of b. R. middle cerebral artery: Lateral parts of temporal and parietal lobestemporal and parietal lobes

Circle of WillisCircle of Willis 1. R. and L. posterior communicating arteries 1. R. and L. posterior communicating arteries connect posterior cerebral arteries with R. and L. connect posterior cerebral arteries with R. and L. anterior cerebral arteriesanterior cerebral arteries2. Anterior communicating artery connects R. and 2. Anterior communicating artery connects R. and L. anterior cerebral arteriorsL. anterior cerebral arteriors

Arteries of Upper Limb and ThoraxArteries of Upper Limb and Thorax

R. subclavian changes to axillary arteryR. subclavian changes to axillary artery1.Thoracoacromial: 1.Thoracoacromial: Superior shoulder&pectoral regionSuperior shoulder&pectoral region

2. Lateral thoracic: Lateral chest wall & breast2. Lateral thoracic: Lateral chest wall & breast3. Subscapular: 3. Subscapular: Scapula, latissimus dorsi & thorax wallScapula, latissimus dorsi & thorax wall

4.4.Ant. & post. circumflex arteries: Deltoid&shoulder jointAnt. & post. circumflex arteries: Deltoid&shoulder joint

Enters arm, axillary changes to brachial arteryEnters arm, axillary changes to brachial artery1.Deep brachial artery: Triceps brachii (post. arm)1.Deep brachial artery: Triceps brachii (post. arm)2. Brachial artery: Ant. flexor muscles of arm2. Brachial artery: Ant. flexor muscles of arm3. Radial artery: Lateral muscles of forearm3. Radial artery: Lateral muscles of forearm4. Ulnar artery: Medial muscles of forearm4. Ulnar artery: Medial muscles of forearm

Arteries of the thorax wallArteries of the thorax wall

1. Internal thoracic artery off subclavian artery1. Internal thoracic artery off subclavian arterya. Anterior intercostal art.s: a. Anterior intercostal art.s: 2. Costocervical trunk gives rise to the first two 2. Costocervical trunk gives rise to the first two posterior intercostals arteriesposterior intercostals arteries3. The thoracic aorta gives rise to the next nine 3. The thoracic aorta gives rise to the next nine pairs: Posterior intercostal spaces & deep muscles pairs: Posterior intercostal spaces & deep muscles of back, vertebral columns & spinal cordof back, vertebral columns & spinal cord

Arteries of the AbdomenArteries of the Abdomen

Abdominal artery lies below level of the diaphragmAbdominal artery lies below level of the diaphragm1. Inferior phrenic arteries: Diaphragm1. Inferior phrenic arteries: Diaphragm2. Celiac trunk: Three branches2. Celiac trunk: Three branchesa.a. Common hepatic Common hepatic b.b. Splenic Splenicc.c. L. gastric artery L. gastric artery

a.a. Common hepatic: Gives branches to stomach, Common hepatic: Gives branches to stomach, small intestine & pancreas (after giving off gastro-small intestine & pancreas (after giving off gastro-duodenal artery, common hepatic becomes hepatic duodenal artery, common hepatic becomes hepatic artery which branches off to R gastroepiploic: artery which branches off to R gastroepiploic: Supplies stomach), then hepatic splits into right & Supplies stomach), then hepatic splits into right & left branches:Supplies liverleft branches:Supplies liver

b.b. Splenic: Splenic: a. Sends branches to stomach and pancreasa. Sends branches to stomach and pancreasb. Splenic terminates in the spleenb. Splenic terminates in the spleenc. Lt gastroepiploic branches: Supplies stomachc. Lt gastroepiploic branches: Supplies stomachc.c. L. gastric artery: Stomach & inferior esophagus L. gastric artery: Stomach & inferior esophagus

Abd. aorta gives Abd. aorta gives Suprarenal arteriesSuprarenal arteries: Adrenal gl.s, : Adrenal gl.s, Superior mesenteric arterySuperior mesenteric artery (gives br.s that supply (gives br.s that supply mesenteric organs (Intestinal: Large intestine, mesenteric organs (Intestinal: Large intestine, Ileocolic: Appendix, colon & R. & middle colic: Ileocolic: Appendix, colon & R. & middle colic: Transverse colon), Transverse colon), Paired renal arteriesPaired renal arteries:Kidneys :Kidneys on each side of body, on each side of body, Gonadal arteries: (Testicular Gonadal arteries: (Testicular or ovarian)or ovarian), , Inferior mesenteric arteryInferior mesenteric artery: Gives br.s : Gives br.s to supply distal part of colon (L. colic, sigmoidal to supply distal part of colon (L. colic, sigmoidal aa , sup. rectal aa), aa , sup. rectal aa), Lumbar arteriesLumbar arteries: Post. : Post. abdominal wall, abdominal wall, Median sacralMedian sacral, , R. & L. common R. & L. common iliacsiliacs

Arteries of Pelvis and LegArteries of Pelvis and Leg

Common iliac divides into two branchesCommon iliac divides into two branches1. Internal iliac: Pelvis & visceral organs (bladder, 1. Internal iliac: Pelvis & visceral organs (bladder, rectum, uterus&vagina(prostate& ductus deferens)rectum, uterus&vagina(prostate& ductus deferens)& br.s to gluteal muscles & external genitalia& br.s to gluteal muscles & external genitalia2. External iliac: Enters thigh becomes femoral art.2. External iliac: Enters thigh becomes femoral art.a. Deep femoral artery: Posterior thigh a. Deep femoral artery: Posterior thigh b. Branches to Lateral & medial circumflex b. Branches to Lateral & medial circumflex arteries: Head & neck of femurarteries: Head & neck of femur

Femoral artery becomes popliteal artery: Knee Femoral artery becomes popliteal artery: Knee region & divides:region & divides:1. Post. tibial artery which gives peroneal artery: 1. Post. tibial artery which gives peroneal artery: Lateral muscles of legLateral muscles of leg2. Anterior tibial artery: Extensor muscles2. Anterior tibial artery: Extensor muscles

Vascular PhysiologyVascular Physiology

Arteries of Pelvis and LegArteries of Pelvis and Leg

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Major Veins of the Systemic CirculationMajor Veins of the Systemic Circulation

Sup. vena cava pours into R atrium. It is a union of Sup. vena cava pours into R atrium. It is a union of L & R brachiocephalic veins. L & R brachiocephalic veins. R. brachiocephalic vein receives:R. brachiocephalic vein receives:1. R. internal jugular vein1. R. internal jugular vein2. R. vertebral vein2. R. vertebral vein3. R. subclavian vein receives R. external jugular3. R. subclavian vein receives R. external jugular*Left side corresponds to right side*Left side corresponds to right side

Inferior vena cava runs from junction of common Inferior vena cava runs from junction of common iliac veins to R. atrium. It receives:iliac veins to R. atrium. It receives:1. Hepatic veins (R. and L.)1. Hepatic veins (R. and L.)2. R. suprarenal vein2. R. suprarenal vein3. Renal veins (R. and L.)3. Renal veins (R. and L.)4. R. gonadal vein4. R. gonadal vein5. Lumbar veins5. Lumbar veins

Veins of Head and NeckVeins of Head and Neck

Drainage of blood from brainDrainage of blood from brain1. Most veins drain into dural (meningial) sinuses1. Most veins drain into dural (meningial) sinusesa. Superior sagittala. Superior sagittalb. Straight b. Straight c. Cavernousc. Cavernousd. Transversed. Transverse2. Most Bd from brain drains into internal jugulars2. Most Bd from brain drains into internal jugulars

Deep veins of face drain into inferior jugularsDeep veins of face drain into inferior jugulars 1. Facial1. Facial2. Superficial temporal2. Superficial temporal

Veins of Upper Limbs and ThoraxVeins of Upper Limbs and Thorax

Azygous system drains thoracic tissuesAzygous system drains thoracic tissues: Post. inter-: Post. inter-costals, hemiazygous & accessory hemiazygous vv costals, hemiazygous & accessory hemiazygous vv drain into azygous v. that drains to sup. vena cavadrain into azygous v. that drains to sup. vena cavaDeep drainage of upper limbDeep drainage of upper limb1. Distal vv of arm drain into ulnar & radial vv1. Distal vv of arm drain into ulnar & radial vv2. Ulnar & radial vv unite to form brachial vein2. Ulnar & radial vv unite to form brachial vein3. Brachial v. enters shoulder becomes axillary v.3. Brachial v. enters shoulder becomes axillary v.4. At level of first rib, it becomes subclavian v.4. At level of first rib, it becomes subclavian v.

Superficial drainage of upper limbSuperficial drainage of upper limb1. Median v. of forearm lies between ulna & radius1. Median v. of forearm lies between ulna & radius (connects either to basilic or cephalic vv)(connects either to basilic or cephalic vv)2. Cephalic vein joins with axillary vein2. Cephalic vein joins with axillary vein3. Basilic vein joins with brachial vein3. Basilic vein joins with brachial vein4. Median cubital v. connects basilic & cephalic vv4. Median cubital v. connects basilic & cephalic vv (commonly used to obtain blood samples)(commonly used to obtain blood samples)

Veins of AbdomenVeins of Abdomen

Hepatic portal systemHepatic portal system1. Multiple hepatic vv from liver to inf. vena cava1. Multiple hepatic vv from liver to inf. vena cava2. Cystic veins drain gall bladder & join hepatic vv2. Cystic veins drain gall bladder & join hepatic vvHepatic portal v drains digestive viscera:Hepatic portal v drains digestive viscera:1. Superior mesenteric1. Superior mesenteric2. Inferior mesenteric: Large intestine & rectum &2. Inferior mesenteric: Large intestine & rectum & joins splenicjoins splenic3. Splenic: Spleen, parts of stomach & pancreas &3. Splenic: Spleen, parts of stomach & pancreas & joins superior mesentericjoins superior mesenteric

Other veins draining into inferior vena cavaOther veins draining into inferior vena cava1. Lumbar veins: R. & L. ascending lumbar veins1. Lumbar veins: R. & L. ascending lumbar veins2. Gonadal veins: R: ovariaries or testes on right 2. Gonadal veins: R: ovariaries or testes on right side of body (directly into vena cava), L: ovariaries side of body (directly into vena cava), L: ovariaries or testes on left side of body (into L. renal vein) or testes on left side of body (into L. renal vein) 3. Suprarenal: R: right adrenal gland (directly into 3. Suprarenal: R: right adrenal gland (directly into vena cava), L: left adrenal gland (into left renal v)vena cava), L: left adrenal gland (into left renal v)4. Renal veins: Drain kidneys4. Renal veins: Drain kidneysCommon iliacs join to form inferior vena cavaCommon iliacs join to form inferior vena cava

Veins of Pelvis and Lower LimbsVeins of Pelvis and Lower Limbs

Ant. & post. tibial vv joins to form popliteal which Ant. & post. tibial vv joins to form popliteal which becomes femoral vein to become external iliac joins becomes femoral vein to become external iliac joins internal iliac to form common iliacinternal iliac to form common iliacSaphenous veinsSaphenous veinsa. Great: Medial aspects of leg, longest v empties a. Great: Medial aspects of leg, longest v empties into femoral vinto femoral vb.Small:Deep fascia of calf, empties into popliteal v b.Small:Deep fascia of calf, empties into popliteal v

Vascular PhysiologyVascular Physiology