Lecture 18: Circulatory System Head, Neck, Upper Limb Flashcards
Pulmonary trunk
Carries deoxygenated blood to lungs
R ventricle branches to R/L pulmonary arteries under arch of aorta
Pathway of aorta
Distributes oxygenated blood to body
From L ventricle (middle mediatstinum) as ascending aorta
Enter superior mediastinum and arches to the L forming arch of aorta
Continues to posterior mediastinum as descending aorta
Descends on L side of vertebral column as thoracic aorta past diaphragm to abdominal cavity as abdominal aorta
Abdominal aorta terminates at LIV and branches into L/R common iliac arteries
Branches of ascending aorta
L/R coronary arteries
Branches of arch of aorta
Brachiocephalic trunk
L common carotid artery
L subclavian artery
Brachiocephalic trunk
Branches into:
R common carotid - for R head/neck
R subclavian - R upper limb
L common carotid artery
Ascends to L side of neck
Supplies to L head/neck
L subclavian artery
Passes under clavicle to L upper limb and continues as axillary artery after passing first rib
Pathway of common carotid artery
Ascends on side of neck at divides into internal and external carotid artery at level of superior border of thyroid cartilage/laryngeal eminence
Internal carotid goes into cranial cavity
External carotid supplies outside of skull (face, neck)
Major branches of external carotid artery
Facial artery - superficial part of face (muscles deep to face, skin)
Superficial temporal artery - soft tissue on surface of temporal bone
Maxillary artery - largest; deep part of the face (oral/nasal/orbital cavity)
Major branches of subclavian artery
Vertebral artery - spinal cord, medulla, cerebellum
Vertebral artery
Passes through transverse foramina of cervical vertebrae and enters via foramen magnum
L/R vertebral artery form basilar artery to supply pons and cerebellum
Basilar artery divides into posterior cerebral arteries to supply inferior cerebral hemisphere and medial surface of occipital lobes
Branches of internal carotid
Middle cerebral artery - largest; temporal and parietal lobe
Anterior cerebral artery - frontal lobe
Communicating arteries
Anterior communicating artery (1) - connects L/R anterior cerebral arteries
Posterior communicating arteries (2) - connects internal carotid and posterior cerebral arteries
Circle of Willis
Composed of posterior cerebral, posterior communicating, internal carotid, anterior cerebral, anterior communicating artery
Enables brain to receive blood if there is a pressure change
Venous system
Superficial veins - within superficial fascia and drain into deep veins
Deep veins - follow synonymous arteries
Dural sinus
Venous channels between layers of dura mater
Large dilated veins
Cavernous sinus
Pair
Middle cranial fossa on either side of hypophyseal fossa of sphenoid bone
Collects from orbital cavity
Superior and inferior sagittal sinus
Unpaired
In superior and inferior margin of falx cerebri
Collects superficial veins of brain
Straight sinus
Unpaired
Receives posterior end of interior sagittal sinus and great cerebral vein; join posterior end of superior sagittal sinus
Transverse sinus
Paired
Posterior margin of tentorium cerebelli to receive superior sagittal and straight sinus
Sigmoid sinus
Paired, S shaped
In groove in mastoid process of temporal bone
Receives all dural sinuses
Great cerebral vein
Collects all deep veins of brain and drains into straight sinus
Internal jugular vein
At level of jugular foramen
Continuation of sigmoid sinus
Travels with internal and common carotid artery, joins subclavian vein behind sternoclavicular joint to form brachiocephalic joint
Recieves blood from face, deep parts of head/neck
Both brachiocephalic veins join together to make the superior vena cava
Anterior and external jugular vein
Superficial veins
Recieves blood from posterior scalp, superficial neck, and drain into subclavian vein
Pathway of subclavian artery
Subclavian continues until 1st rib, then becomes axillary artery (between lateral border of first rib to lower margin of teres major) - supplies walls of axilla
Becomes brachial artery from lower margin of teres major to cubital fossa - supplies anterior compartment of arm
Has branch deep brachial artery - supplies posterior compartment of arm
Brachial artery splits into ulnar (medial) and radial (lateral) artery - supplies muscles of forearm)
Branch of ulnar artery - common interosseous artery - supplies deep muscles of forearm
Ulnar and radial arteries form arterial arches (superifical and deep palmar arches) which will give rise to digital arteries - supplies fingers
Pathway of upper limb veins
2 venous plexi: palmar and dorsal which have 2 superficial veins - basilic (medial), and cephalic (lateral)
Basilic and cephalic vein communicate by median cubital vein (elbow region)
Basilic vein drains into brachial vein (deep vein) creating the axillary vein
Cephalic vein drains into axillary vein
Axillary vein become subclavian vein past rib 1
Subclavian vein also receives external jugular vein, and joins the internal jugular vein to from the brachiocephlic vein
Brachiocephlic vein joins the opposite side to form the superior vena cava
