Anatomy 8

The Venous System is responsible for

Returning deoxygenated blood to the heart from the body’s tissues.

• Transports deoxygenated blood back to the heart.

Deep Veins

Accompany arteries, and share their names

Superficial Veins

Near the body surface, do NOT accompany veins.

Unlike arteries, veins have:

thinner walls, low blood pressure and valves to prevent backflow of blood

Larger veins function

as blood reservoirs (contain around 60% of blood volume)

Superior Vena Cava

Formed by the union of the right and left brachiocehaplic veins

• Drains upper body

Inferior Vena Cava

Formed by the union of the right and left common iliac veins

• Drains lower body

Coronary Sinus

Collects venous blood from the heart muscle and empties into the right atrium.

Pulmonary Veins

Return oxygenated blood from the lungs to the left atrium of the heart.

Major Veins Entering the Heart

1. Superior Vena Cava

2. Inferior Vena Cava

3. Coronary Sinus

4. Pulmonary Veins

The Azygos System

Drains the walls and organs of the Thoracic Cavity

Azygos Vein

Drains the Right Intercostal Veins, empties into the Superior Vena Cava

Hemiazygos Vein

Drains from the Left intercostal veins, empties into the azygos vein

Accessory Hemiazygos Vein

Descends along the vertebral column to empty into the Hemiazygos vein.

Collects blood from the upper left intercostal spaces.

Parts of the Azygos System

1. Azygos Vein

2. Hemiazygos Vein

3. Accessory Hemiazygos Vein

Tributaries of the Inferior Vena Cava

• Parietal Tributaries

  • Lumbar and Inferior Phrenic Veins

• Visceral Tributaries

  • Hepatic Veins

  • Renal Veins

  • Right Gonadal Vein

  • Left Gonadal Vein

Lumbar Veins (Parietal)

Drain the walls of the lower back

Inferior Phrenic Veins (Parietal)

Drain the underside of the diaphragm

Hepatic Veins (Visceral)

Drain blood from the liver

Renal Veins (Visceral)

Drain the kidneys

Right Gonadal Vein

Drains the right ovary/testicle into the inferior vena cava.

Left Gonadal Vein

Drains into the left renal vein before reaching the inferior vena cava.

The Hepatic Portal System

Filters blood from the digestive organs before it enters systemic circulation.

The Hepatic Portal System Veins

1. Inferior Mesenteric Vein

2. Splenic Vein

3. Superior Mesenteric Vein

4. Portal Vein

Inferior Mesenteric Vein (Hepatic)

Drains the last half of the large intestine

Splenic Vein (Hepatic)

Drains the pancreas, spleen, and stomach

Superior Mesenteric Vein (Hepatic)

Drains the small intestine and first half of the large intestine

Portal Vein (Hepatic)

Formed by the union of the splenic and superior mesenteric veins.

The Dural Sinuses

The Brain Drainage System.

Veins that drain blood from the brain into the internal jugular vein,

Major Dural Sinuses

1. Superior and Inferior Sagittal Sinuses

2. Transverse Sinuses

3. Sigmoid Sinuses

Sigmoid Sinuses

Drain into the internal jugular vein

Veins of the Face and Neck

Internal and External Jugular Veins

Internal Jugular Vein (Face and Neck Vein)

Drains the brain and deep structures of the face.

UNITES with the subclavian vein to from the brachiocephalic vein.

External Jugular Vein (Face and Neck Vein)

Drains the scalp and superficial face

Empties into the subclavian vein.

Deep Veins of the Arm Have:

The same names as the arteries

Deep Veins of the Arm

1. Radial and Ulnar Veins

2. Brachial Veins

3. Axillary Veins

Radial and Ulnar Veins (Deep Vein, Arm)

Formed in the forearm, unite to form the brachial vein

Brachial Vein (Deep Vein, Arm)

Courses up the upper arm and joins with the basilic vein to form the axillary vein

Axillary Vein (Deep Vein, Arm)

Becomes the subclavian vein at the first rib.

Superficial Veins of the Arm

1. Cephalic Vein

2. Basilic Vein

3. Median Cubital Vein

Cephalic Vein (Superficial Vein, Arm)

Runs along the lateral arm and empties into the axillary vein

Basilic Vein (Superficial Vein, Arm)

Runs along the medial arm and unites with the brachial vein

Median Cubital Vein (Superficial Vein, Arm)

Connects the cephalic and basilic veins.

Common site for Venipunture (blood draws)

Median Cubital Vein

The Deep Veins of the Leg Have:

The same names as the leg arteries

Deep Veins of The Leg:

1. Anterior and Posterior Tibial Veins

2. Popliteal Vein

3. Femoral Vein

Anterior and Posterior Tibial Veins (Deep Vein, Leg)

Merge to form the popliteal vein behind the knee

Popliteal Vein (Deep Vein, Leg)

Receives tributaries from the tenicular veins

• Drain the knee region

Femoral Vein (Deep Vein, Leg)

Formed as the popliteal vein passes through the adductor magnus muscle

Becomes the external iliac vein at the inguinal ligament

The Femoral Vein Becomes the External Iliac Vein at

the inguinal ligament

Superficial Veins of the Leg

1. Great Saphenous Vein

2. Small (Lesser) Saphenous Vein

Great Saphenous Vein (Superficial Vein, Leg)

The LONGEST VEIN in the body

Begins on the medial side of the foot, empties into the femoral vein.

• Used in Coronary Artery Bypass Graft Surgeries

Small (Lesser) Saphenous Vein (Superficial Vein, Leg)

Begins on the lateral side of the foot, empties into the popliteal vein.

Varicose Veins

Occurs when valves in superficial veins weaken, causing blood to pool.

• Common in the Great Saphenous Vein

Deep Vein Thrombosis (DVT)

Formation of blood clots in deep veins, usually in the legs.

• Leads to pulmonary embolism if clot travels to the lungs.

The Hepatic Portal System is Important Because It:

• Filters toxins and harmful substances before entering general circulation.

• Plays a role in metabolism by regulating glucose and fat storage

Veins in Circulatory Homeostasis

Function as blood reservoirs and help regulate blood pressure.

Venous return is aided by:

• Skeletal Muscle Contraction (Muscle Pump)

• Respiratory Movements (Breathing Assists Venous Flow)

• Venous valves prevent backflow

The Fetus gets Oxygen and Nutrients Through:

The placenta

Fetal Circulatory System

Allows the fetus to bypass underdeveloped organs.

Fetal Circulatory Pathways

Close after birth

The Umbilical Vein

Carries oxygen-rich blood and nutrients from the placenta to the fetus.

Enters the fetal body through the Umbilicus.

The Umbilical Vein 2 Pathways

1. Ductus Venous (Bypasses the Liver)

2. Portal Vein (Sends blood THROUGH the Liver)

Umbilical Vein After Birth

Atrophies and forms the Ligamentum Teres of the Liver.

• Portion of umbilical vein inside the body becomes NONFUNCTIONAL.

The Foramen Ovale

An opening in the Atrial Septum that is a Shortcut Between Atria that Bypasses the Pulmonary System

Allows 1/3 of blood entering the right atrium pass directly into the left atrium

The Foramen Ovale Bypasses the Pulmonary System Because

The Lungs are Not Functional in Utero

The Foramen Ovale After Birth

1. The opening closes

2. Then forms a Small Depression (Fossa Ovalis)

The Umbilical Arteries

Carry Deoxygenated blood and waste products from the fetus to the placenta.

The Umbilical Arteries Location

Branch off of the fetus’s internal iliac arteries

Exit through the umbilicus and wrap around the umbilical vein.

The Umbilical Arteries After Birth

1. Close and Atrophy

2. Become Ligamentous Structures in the Abdominal Wall

Lungs expand

Pulmonary circulation begins.

Which venous disorder occurs when inflammation affects a vein, sometimes leading to blood clot formation?

Phlebitis

Which vein is most likely to be affected by varicose veins?

Great Saphenous Vein

Which vein is formed by the union of the right and left brachiocephalic veins?

Superior Vena Cava

Which large vein returns blood from the lower extremities and abdomen to the heart?

Inferior Vena Cava

The lymphatic system has an extensive network of small vessels called

Lymphatic

The blood vessels that carry blood toward the heart are the

Veins

What structure allows venous blood to bypass the liver and drain directly into the inferior vena cava?

Hepatic Veins

Peyer's patches are lymph nodes embedded

In the walls of the small intestine

Which deep vein of the upper limb merges with the basilic vein to form the axillary vein?

Brachial Vein

Which venous system drains blood from the thoracic walls and some thoracic organs?

Azygos System

Which venous disorder is characterized by swollen, twisted veins due to valve failure?

Varicose Veins

Which of the following structures is an orifice of the heart through which deoxygenated blood will pass?

Superior Vena Cava Orfice

What is the primary function of the hepatic portal system?

Filter blood from the digestive system before it enters circulation

Which superficial vein is the longest in the body and is commonly used in coronary bypass surgery?

Great saphenous vein

The blood vessels responsible for draining blood from the tissues of the brain are the

Dural Sinuses

What is the primary function of the venous system?

Return deoxygenated blood to the heart

What structure helps prevent backflow in veins, particularly in the lower extremities?

Valves

Which type of veins accompany arteries and typically share the same name?

Deep veins

Which veins are located near the surface of the body and do not accompany arteries?

Superficial veins

Which of the following joins the subclavian vein to form the innominate vein?

Internal Jugular Vein

Which deep vein of the upper limb merges with the basilic vein to form the axillary vein?

Brachial Vein

Which deep veins of the lower leg merge to form the popliteal vein?

Anterior and Posterior Tibial Veins

What is the name for the paired veins that accompany the same artery of the same name?

Venae Commitantes (companion veins)

The brachiocephalic veins are formed by

the union of the internal jugular vein and the subclavian vein

Veins draining the abdominal region are divided into

Parietal (Drain Walls of abdominal cavity)

Visceral Tributaries (Drain Organs in abdominal cavity)

Right suprarenal veins

Drain the adrenal glands

The splenic vein and superior mesenteric vein unite to form

the portal vein, which enters the liver

Venous Insufficiency

A condition where veins cannot efficiently return blood to the heart, causing swelling, pain, and skin changes.

Foramen ovale closes →

Becomes the fossa ovalis.