Major Vessels

Pulmonary/Systemic Circuits

  • pulmonary circuit

    • pulmonary trunk (from right ventricle) → pulmonary arteries → lungs

      • blood deoxygenated

    • gas exchange occurs within lungs

    • pulmonary veins to left atrium of heart

      • blood oxygenated

  • systematic circuit

    • blood leaves left ventricle → aorta (ascending/descending)

    • blood enters right atrium ← vena cava (SVC/IVC)

Arterial Receptors

  • sensory structures in walls of major aa.

    • monitor BP and blood chemistry

    • transmit informaton to the brainstem

      • regulates HR, BV diameter, and respiration

    • baroreceptors in carotid and aoritc sinuses

      • monitor BP from iinternal carotid aa. and aorta

      • transmit via glossopharyngeal and vagus nn.

      • baroflex - keeps BP steady by rapidly adjusting cardiac output to match arterial BP

  • chemoreceptors

    • carotid bodies

      • monitor blood chemistry

      • transmit signals via glossopharynealgeal nerve

        • adjust respiratory rate to stabilize pH, CO2, and O2

    • aoritc bodies

      • similar to carotid bodies

        • innervated by vagus nerve

Arteries

  • major aa. include:

    • aorta and its branches

      • arch, thoracic aorta, and abdominal aorta

    • head/neck aa.

      • circle of willis

    • appendicular aa.

Aorta (& Branches)

  • aortic arch

    • branchiocephalic trunk

      • right common carotid a. (right of head)

      • righ subclavian a. (right shoulder/UL)

    • left common carotid a. (left of head)

    • left subclavian a. (left shoulder/UL)

  • ascending aorta

    • right/left coroary aa.

  • descending aorta

    • thoracic aorta and abdominal aorta

      • arteries associated with esophagus, lungs, liver, spleen, kidneys, intestines, testes/ovaries, and various muscles

Head and Neck

  • common carotids

    • internal carotid a.

    • external carotid a.

  • vertebral aa.

    • from subclavian aa.

    • come together to form Basilar a.

      • circle of willis

  • Circle of willis

    • internl carotid aa.

    • vertebral aa.

      • basilar a.

      • cerebellar aa.

      • pontine aa.

      • cerebral aa.

        • communicating aa.

Thorax and Upper Limb

  • subclavian aa.

  • axillary aa.

  • brachial aa.

    • radial aa.

      • deep/superficial palmar arches

    • ulnar aa.

      • interosseous aa.

      • deep/superficial palmar arches

Abdominopelvic

  • celiac trunk

    • common hepatic a.

    • splenic a.

    • left gastric a.

  • superior mesenteric a.

  • renal aa.

  • gondal aa.

    • ovarian/testicular aa.

  • inferior mesenteric a.

  • common iliac aa.

  • internal iliac a.

Lower Limb

  • common iliac aa.

    • internal iliac aa.

    • external iliac aa. → femoral aa.

      • deep femoral

      • popliteal aa.

        • posterior tibial aa.

          • fibular aa.

        • anterior tibial aa.

          • dorsal pedal aa.

Venous Sinuses

  • some veins expand to form venous sinuses

    • thin walls, large lumens, and no smooth muscle

    • not capable of vasomotor responses

    • e.g.dural venous sinus and coronary sinus

Major Veins

  • superior vena cava

    • jugular, vertebral, axillary vv. drain into the subclavin vv., which then drain into the brachiocephalic vv. → SVC

  • inferior vena cava

    • iliac, hepatic, renal, and gonadal vv. drain here

Head and Neck

  • dural sinuses

  • internal jugular vv.

  • exxternal jugular vv.

Dural Sinuses

  • drain blood from brain into intenal jugular vv.

    • also drain CSF via arachnoid granulations

  • 5 unpaired sinuses: superior sagittal, inferior sagittal, straight, occipital, and intercavernous

  • confluence of the sinuses

  • 5 paired sinuses: transverse, sigmoid, cavernous, superior petrosal, and inferior petrosal

  • confluence of the sinuses

Thorax

  • blood from tissues and organs in the thorax drained by the intercostal veins and azygos vein

    • azygos v. formed by right lumbar v. and right subcostal v.

  • azygos vein system drains to the SVC

    • hemiazygos and accessory hemiazygos vv. drain into azygos v.

Upper Limbs

  • deep and superficial veins

  • hand vv. drain into forearm

    • deep/superficial venous palmar arches/network

      • radial, ulnar, cephalic, and basilic

  • forearm drains to arm

    • basilic, radial, and ulnar vv. drain to the axillary vv.

    • median cubital vv.

      • between cephalic and basilic

  • arm to subclavian vv. →brachiocephalic vv. → SVC

Abdomen

  • veins drain into the IVC

    • internal iliac and external iliac vv.

      • drain into the common iliac vv.

    • gonadal vv.

      • ovarian vv.

      • testicular vv.

    • renal vv.

    • hepatic vv.

    • phrenic vv.

Lower Limbs

  • foot drains to crural region → drains to leg

    • dorsal vv. superficial and drain to small saphenous vv. → great saphenous vv.

      • great saphenous vv. drains to femoral vv.

    • plantar vv. deep and drain to fibular, anterior tibial, and posterior tibial vv.

      • popliteal vv. → femoral vv.

  • femoral vv. drain into the external iliac vv. → IVC

FUN VESSEL FACTS

  • if all vessles from one body were laid end-to-end, they would stretch over 60,000 miles

    • could circle the earth twice (80% from capillaries)

  • veins appear blue through skin due to light reflection, but venous blood is actually dark red

  • Galen (2nd century) was the first to describe circulation

    • thrught venous blood was made in the liver and that there were 2 one-way systems for blood

    • theory held until william henry corrected in the 1600s

  • superficial veins play a role in thermoregulation

    • dilate to release heat; constrict to conserve heat

  • great saphenous vein = longest in body