Kategorien: Alle - muscles

von Corey Segrest vor 4 Tagen

18

Thorax and Abdomen

The posterior abdominal wall comprises various structural components, including muscles, nerves, vessels, and fascia. Key muscles in this area include the quadratus lumborum, which aids in lumbar stabilization and pelvic tilting, and the psoas major, responsible for hip flexion and rotation.

Thorax and Abdomen

Thorax and Abdomen

Thorax

Respiratory system
physiology

Gas transport

Oxy-hemoglobin binding curve

PCO2

Temp

Ph

CO2 transport

Plasma CO2

7% dissolved directly

Hemoglobin bound CO2

23%

Bicarbonate

about 70% of CO2

O2 transport

Hemoglobin

98% of O2 transport

Binds up to 4 O2 molecules

Respiration (gas exchange)

Respiratory control mechanisms

Neuronal influence

Conscious and unconscious can effect breathing rates

Brain stem control

Pons and medulla regulate respiration

Chemoreceptors

Periphrail

Responds to PO2, PCO2 and pH changes

Medulla

Sensitive to cerebrospinal CO2

Perfusion

Transfer efficiency

Oxygen availabilty

Hypoxia

Ventilation

Patterns of ventilation

Minute ventilation

Diameter of airways

viscosity of air

Airway resistance

Lung volumes and capacity

Gas laws

Dalton's law

How gases are exchanged in respiratory system

Boyle's law

How changes in lung volume affect air pressure during breathing

High to low pressure

Vocalization

Voice is generated by airflow from the lungs. When the air from the lungs blows through the vocal folds

Ph regulation

controlling the amount of carbon dioxide (CO2) exhaled

Protection

Against pathogens

Sticky layer of mucous over cilia to trap large particles

Ciliated epithelium in watery saline layer

Conditioning of air

Humidifying

Add water vapor

Warming

To body temp

Gas excahnge

Transport

Movement of O2 and CO2 in blood

Exchange 3

Gas exchange between blood and tissues

Exchange 2

Gas exchange between alveoli and lung capillaries

Exchange 1

Pulm ventilation and alveolar ventilation

Alveoli

Tertiary bronchi

Secondary bronchi

L & R bronchi

Cardiovascular system
Blood

Pressure

Diastolic: The lowest pressure between heartbeats

Systolic: The highest pressure when the heart beats

Flow

Factors effecting blood flow

Viscosity

incr in viscosity = decr cardiac output

Length

Shorter vessel length = better flow

Diameter

Greater diameter = better flow

Friction force

Less friction = better flow

Pressure gradient

high to low pressure

temperature regulation

pathogen defense

remove metabolic waste

Transport vital substances

Physiology of the heart

Heart sounds

Second sound

Semilunar valves closing

First sound

AV valves closing

Cardiac output

Factors

Neural influence

SNS

Increases HR and contractility (Epi and norepi)

PNS

Reduces HR (acetylcholine)

Venous return

skeletal muscle pump, respiratory pump

Frank-Starling

Incr stretch= incer contraction force

Equation

HR x SV

Stroke volume

Amount of blood pumped by one ventricle in contraction

ejection fraction - % of EDV ejected with one contraction

Cardiac cycle

EKG

T wave

Ventricular repolarization

QRS complex

Ventricular depolarization

P wave

Atrial depolarization

Phases

Isovolumetric relaxation

residual blood remains (end systolic volume

all valves closed

ventricles relax

Ventricular ejection

blood is ejected into arteries

Semilunar valves are open

Isovolumetric ventricular contraction

all valves are closed (no ejection)

ventricles contract

Atrial systole

additional blood enters ventricles

atria contracts

Late diastole

both atria and ventricle are relaxed

Mechanical events

Diastole

passive filling of ventricles

70% of blood volume

Relaxation

Systole

Atrial kick

Contraction

Conduction system

Bundle of His and purkinje fibers

spread electrical signal to ventricles

Av node

Subtopic

Slows down conduction to allow atrial contraction

SA node

initiates depolarization and sets HR

right atrium

cardiac cells

types

Contractile

99%

-90 mV resting membrane potential

respond to action potentials

Autorhythmic

-60mV pacemaker potential

1%

Generate action potentials

Characteristics

Contractility

Cardiac contractility is the heart's ability to contract and pump blood. It's also known as inotropy.

Conductivity

The heart's conductivity refers to the ability of its cells to generate and conduct electrical impulses that control the heartbeat:

Excitability

Cardiac excitability is the ability of heart cells to depolarize and repolarize and to propagate electrical activity to other cells

Rhythmicity

The heart's rhythmicity is the ability of the cardiac muscle to depolarize and repolarize in a stable and repetitive manner

Automaticity

The heart's automaticity is the ability of cardiac cells to spontaneously generate electrical impulses, or action potentials without external stimulation

Anatomy of the heart

Valves

Aortic

Aortic valve: Located between the left ventricle and aorta

Mitral/bicuspid

Mitral valve: Located between the left atrium and left ventricle

Pulmonary

Pulmonary valve: Located between the right ventricle and pulmonary artery

Tricuspid

Tricuspid valve: Located between the right atrium and right ventricle

Chambers

L ventricle

Left ventricle: Pumps oxygenated blood to the aorta, which distributes it to the rest of the body

L atrium

Left atrium: Receives oxygenated blood from the lungs through the pulmonary veins

R ventricle

Right ventricle: Pumps blood to the lungs to receive oxygen

R atrium

Right atrium: Receives blood from the body that's low in oxygen

Endocardium

keeps the blood flowing through the heart separate from the myocardium, or cardiac muscles

Myocardium

Coordination: The myocardium contracts in a coordinated fashion to resist fatigue.

Force generation: The myocardium generates enough force to supply the body's metabolic demands.

Contraction: The myocardium contracts and relaxes rapidly and involuntarily to pump blood throughout the body.

Pericardium

positions the heart in the mediastinum and limits its motion while providing a lubricated slippery surface for the heart to beat inside and the lungs to move outside

Major vessels

Pulmonary Veins

the right pulmonary vein carries oxygenated blood from the right lung to the left atrium

The left pulmonary vein carries oxygenated blood from the left lung to the left atrium of the heart

Pulmonary trunk

R pulm artery

Supplies blood to right lung

L pulm artery

Supplies blood to left lung

Inferior VC

Superior VC

The right and left brachiocephalic veins join to form the SVC

In the superior and middle mediastinum

R coronary

Marginal

supplies the majority of the myocardium of the right ventricle of the heart.

supplies blood to the bottom of the heart

L coronary

circumflex

Supplies oxygenated blood to the left atrium and the back and outer areas of the heart's left ventricle

Ant interventricular

supplies blood to the left ventricle, the interventricular septum, and a small section of the right ventricle's outflow tract

L subclavian

supply oxygen-rich blood to the upper body, including the left arm, neck, head, and back of the brain

L common Carotid

supplying oxygenated blood to the head and neck

R Brachiocephalic Trunk

R subclavian

supply oxygen-rich blood to the right upper extremity

R common carotid

Supplies blood to brain

openings

Aortic Hiatus

Azygos vein

Part of the azygos venous system, which helps circulate blood and deliver oxygen and nutrients to tissues. The azygos vein also creates a collateral pathway between the superior vena cava (SVC) and the inferior vena cava (IVC).

Located on the right side of the middle back of the chest, along the right side of the vertebral column

Desc. Aorta

The descending aorta is the part of the aorta that runs from the aortic arch down through the chest and into the abdomen:

Esophageal opening

Vagal trunks

Posterior vagal trunk

Supplies the foregut and midgut with visceral sensory and parasympathetic innervation.

Anterior vagal trunk

Supplies the abdominal esophagus, cardia, lesser curvature, and superior portion of the stomach. It also branches into the hepatic branch, which supplies the liver, gallbladder, and biliary apparatus.

move food and liquids from the mouth to the stomach.

Caval opening

T8

Inferior Vena Cava

L/R crus and arcuate ligaments

Left crus: Originates from the upper two lumbar vertebrae and intervertebral discs.

Right crus: Originates from the first three lumbar vertebrae and intervertebral discs

Central tendon

The vena caval foramen is an opening in the central tendon that allows the inferior vena cava and right phrenic nerve to pass through.

During inhalation, the central tendon is pulled down by the diaphragm, which expands the chest cavity and allows air to enter the lungs.

The central tendon is made up of multiple planes of fibers that intersect at various angles to form bundles that give it strength.

L/R Phrenic nerve

R

Right phrenic nerve: Controls the right side of the diaphragm

L

Left phrenic nerve: Controls the left side of the diaphragm

Mediastinum

The ascending aorta is a key part of the circulatory system, helping the heart pump blood throughout the body.

The ascending aorta is the initial portion of the aorta that extends behind the sternum, ending at the level of the T4 vertebral body.

The descending aorta is the part of the aorta that runs from the aortic arch down through the chest and into the abdomen:

Thoracic duct

courses posterior to the esophagus at the T7 level and crosses over the midline to the left side of the thorax around the T5 vertebral level.

The thoracic duct's primary function is to transport lymph from the body's tissues into the circulatory system:

Internal thoracic

vein

Deep in the chest, near the sternum

collects blood from the chest wall and breasts and returns it to your heart

artery

The ITA terminates at the level of the sixth rib, dividing into the superior epigastric and musculophrenic arteries.

The ITA originates from the subclavian artery, a few centimeters below the origin of the thyrocervical trunk.

The ITA runs along the inner surface of the anterior chest wall, about 2–3 centimeters from the sternum and slightly medial to the nipple.

Vagus nerve

The phrenic nerve originates from the C3 through C5 nerve roots in the spinal cord.

The phrenic nerve travels through the neck and chest, past the heart and lungs, to reach the diaphragm.

The phrenic nerve controls the diaphragm's contraction and relaxation and provides sensory information about touch and pain to the diaphragm and surrounding tissues.

Sympathetic chain

network of nerve fibers that runs parallel to the vertebral column on either side of the body

Function: Carries preganglionic fibers from the spinal cord that synapse in ganglia, which then send postganglionic fibers to the viscera

Regions: Divided into cervical, thoracic, lumbar, and sacral segments

Structure: Consists of 22 pairs of interconnected neuronal cell bodies

Location: Extends from the base of the skull to the coccyx

The esophagus is a muscular tube in the center of the chest that connects the throat to the stomach:

The esophagus is located in the mediastinum, behind the trache and in front of the spine. It passes through the diaphragm and enters the abdominal cavity.

Lubrication: The esophagus produces mucus to help food pass through.

The esophagus's primary function is to move food and liquids from the mouth to the stomach

Trachea

Larynx: The upper part of the trachea that contains the vocal cords.

Cricoid cartilage: A ring of cartilage that surrounds the trachea in the middle of the neck.

Mucosa: A substance that lines the cartilage rings.

Cartilage rings: The trachea is made up of circular cartilage rings that support the trachea and prevent it from collapsing when you exhale.

location

The trachea is located in the neck and upper chest, between the collarbones and below the larynx

Cartilage support

Air filtration

Disease defense

Temperature regulation

The trachea's primary function is to allow air to pass into and out of the lungs.

Thymus gland

The thymus gland is located in the upper chest, in the mediastinum, between the lungs, and in front of and above the heart:

The thymus gland's main function is to produce and mature T cells, a type of white blood cell that helps the body fight infection:

Great Vessels

The IVC's main function is to return blood from the lower body to the heart. The heart then pumps the blood to the lungs to pick up oxygen.

The IVC is located along the right side of the vertebral column and passes through the diaphragm.

Superior vena cava

The right and left brachiocephalic veins join to form the SVC

In the superior and middle mediastinum

Carries blood from the head, neck, arms, and chest to the heart

Aortic Arch

Distributes blood to the head and upper body, and helps regulate blood pressure

Between the ascending and descending aorta in the upper mediastinum

Pulmonary A/V

Pulm A

transport deoxygenated blood from the right side of the heart to the lungs for oxygenation

Pulm V

The pulmonary veins carry oxygen-rich blood from the lungs to the heart, where it is then pumped to the rest of the body

Rib cage

Scalenes

act as postural muscles in maintaining the position of the cervical tract or playing an active role in the movements of the neck

Posterior - 2nd rib

Anterior middle- 1st rib

Transversus thoracis

Helps to depress the ribs during forced exhalation

Located on the inner surface of the anterior thoracic wall

Innermost intercostals

They stabilize the ribs during normal breathing and depress the ribs during forced exhalation.

They are found in the middle two-thirds of the intercostal spaces, deep to the internal intercostal muscles and intercostal vessels and nerves.

Internal intercostals

The internal intercostal muscles contract to depress the ribs and push air out of the lungs during forced exhalation. They are also important for normal speech and singing.

The internal intercostal muscles are located in the middle of the three intercostal muscle layers in the thorax, deep to the external intercostal muscles. They extend from the front of the ribs, around the back, and past the bend in the ribs.

External intercostals

When you inhale, the external intercostal muscles contract, which raises and spreads the ribs apart, expanding the chest cavity and allowing the lungs to fill with air.

The posterior intercostal veins are a set of veins that drain the back of the thoracic cavity:

Neurovascular supply

Posterior intercostal vessels

Posterior intercostal vein

The posterior intercostal veins are a set of veins that drain the back of the thoracic cavity

Posterior intercostal artery

The posterior intercostal arteries are a set of blood vessels that supply the chest wall, back, and spine:

Intercostal nerves: ventral rami of T1-T12

Paired internal thoracic artery and veins

small paired vessel that drains blood from the chest wall, breasts, diaphragm, and part of the mediastinum back to the heart

a paired artery that supplies blood to the anterior chest wall, breasts, and upper abdomen

Paired ribs

11-12 are floating and not attached to anterior rib cage

8-10 articulate with cartilage superior to them

Ribs 1-7 attach to sternum via cartilage

Angle of rib

located lateral to the tubercle and is marked by a prominent linear ridge on the ribs external surface

an area of the body of tenth rib where its curvature changes sharply

Costal groove

provides an attachment site for the innermost intercostal muscle.

Superior aspect for neruo structures

Shaft

The shaft of the rib cage is the body of the rib, which is a flat, curved, and thin bone

Tubercle

Attach to transverse process of T vertebrae

The neck of a rib is the flattened part that connects the head of the rib to the body, or shaft

Head with 2 articular facets
Atypical

1,2,11,12

Typical

3-10

Boundaries of thorax

12 thoracic vertebral bodies

Sternum

Xiphoid process

Manubrium

Lateral

Ribcage

1st rib

Abdomen

Quadrants
LLQ

sigmoid colon, part of the descending colon, the left ovary (in females), the left fallopian tube (in females), the left ureter, portions of the small intestine (especially the ileum), and various blood vessels and lymphatics, including branches of the abdominal aorta and iliac arteries.

cecum, appendix, right ovary (in females), right fallopian tube (in females), right ureter, the lower pole of the right kidney, portions of the ileum (small intestine), and various blood vessels and lymphatics, including branches of the abdominal aorta and iliac arteries.

left portion of the liver, the larger portion of the stomach, the pancreas, left kidney, spleen, portions of the transverse and descending colon, and parts of the small intestine

right portion of the liver, gallbladder, right kidney, a small portion of the stomach, portions of the ascending and transverse colon, and parts of the small intestine

Peritoneum & Peritoneal Cavity
Subdivisions

Omental bursa

Allows stomach to move freely

Omental foramen

allows communication between the greater and lesser sacs of the peritoneal cavity

Formations

Omentum

Connects liver to stomach

Fat deposition, having varying amounts of adipose tissue. Immune contribution, having milky spots of macrophage collections. Infection and wound isolation

Mesentery

The mesentery is a fold of membrane that attaches the intestine to the wall around the stomach area and holds it in place.

The inner layer that covers the lungs, blood vessels, nerves, and bronchi

Parietal

The outer layer that attaches to the chest wall.

Diaphragm
dome-shaped muscle that separates the thoracic cavity from the abdominal cavity
Actions

Exhale

When the diaphragm relaxes, it moves upwards, compressing the chest cavity and pushing air out of the lungs.

Inhale

When the diaphragm contracts, it moves downwards, creating a vacuum in the chest cavity that pulls air into the lungs.

Nerve

Phrenic nerve

Sensory: The phrenic nerve provides sensation to the central tendon of the diaphragm

Motor: The phrenic nerve causes the diaphragm to contract when you inhale

C3 through C5

Lower internal intercostal arteries: Supply blood to the diaphragm

Inferior phrenic arteries: Often arise from the anterior trunk of the aorta above the celiac artery

Pericardiacophrenic artery: A branch of the internal thoracic artery

Musculophrenic artery: A branch of the internal thoracic artery

Superior phrenic arteries: Arise from the thoracic aorta

Anterio-lateral Abdominal Wall
Inuinal region

Inguinal canal

walls

Roof

formed by the medial crus of the aponeurosis of the external oblique, the musculoaponeurotic arches of the internal oblique and transverse abdominal muscles, and the transversalis fascia.

formed by the transversalis fascia, conjoint tendon, and deep inguinal ring.

Anterior

composed of the aponeurosis of the external oblique muscle and reinforced laterally by the internal oblique muscle.

Floor

lancunar ligament

superficial ring

The exit point for the inguinal canal, which allows passage for the spermatic cord in males, the round ligament in females, blood vessels, lymphatics, and the ilioinguinal nerve

Location: Located above the pubic tubercle, just superior to the crest of the pubis

Deep ring

serve as the entrance point of the inguinal canal, allowing the passage of the spermatic cord in males and the round ligament of the uterus in females

It is an opening in the transversalis fascia, forming the deep boundary of the inguinal canal.

Iliopubic tract

The iliopubic tract is a band of tissue that runs from the iliopectineal arch to the pubic bone

Inguinal ligament

The inguinal ligament is a band of tissue that runs from the pubic tubercle to the anterior superior iliac spine (ASIS) in the lower abdomen.

It's also known as Poupart's ligament or groin ligament

Spermatic cord

Lymphatic vessels

Fight infection

The lymphatic vessels of the scrotum drain into the superficial inguinal lymph nodes.

Cremaster muscle

raise and lower the testes in order to regulate scrotal temperature for optimal spermatogenesis and survival of the resultant spermatozoa.

Plexus

Helps regulate temperature

web-like network of veins in the spermatic cord that surrounds the testicular artery. It begins in the scrotum and extends into the inguinal canal.

Arteries

testicular

Also known as the internal spermatic artery, this artery branches from the abdominal aorta and supplies blood to the testis, epididymis, and spermatic cord.

cremasteric

A branch of the inferior epigastric artery, this artery supplies blood to the skin of the scrotum, including the cremaster muscle, and the layers of the spermatic cord.

Ductus deferens

Runs through the spermatic cord, inguinal canal, and pelvic cavity, looping over the bladder and ending at the ejaculatory duct

Carries sperm from the epididymis to the urethra

Layers

External spermatic fascia

Internal spermatic fascia

Neruovasculature

femoral artery

superficial circumflex

supplies blood to the skin, subcutaneous tissue, and superficial inguinal lymph nodes of the abdominal wall and groin

superficial epigastric

The superficial epigastric artery's main function is to supply blood to the skin and superficial inguinal lymph nodes of the anterior abdominal wall

External iliac

deep circumflex iliac

The deep circumflex iliac artery (DCIA) supplies blood to the muscles, skin, and bone of the lower abdomen and pelvis

inferior epigastric

The inferior epigastric artery supplies oxygen-rich blood to the abdominal wall, including the skin, muscles, and parts of the male reproductive system

Aorta

subcostal

The subcostal arteries supply the muscles and skin beneath the 12th rib of the anterolateral abdominal wall

posterior epigastric

Supplies blood to the upper part of the rectus abdominis muscle and the linea semilunaris

Internal Thoracic

superior epigastric

The superior epigastric artery supplies blood to the upper central abdominal wall and skin, and the upper rectus abdominis muscle:

musculophrenic

The musculophrenic artery is a branch of the internal thoracic artery that supplies the pericardium and abdominal wall:

Ilioinguinal

Iliohypogastric

Lateral cutaneous

T7-T9

Thoracoabdominal

T7-T12

Internal surface

Peritoneal fossae

supravesical

medial inguinal

Lateral inguinal

Peritoneal folds

Lateral umbilical

Median umbilical

Transverse section

Below umbilicus

Rectus sheath anterior to rectus

Above umbilicus

Rectus sheath splits around the rectus

Rectus shealth

fibrous compartment in the abdomen that contains the rectus abdominis and pyramidalis muscles

Pyramidalis

Function: Considered to have a minor role in stabilizing the abdominal wall by tensing the linea alba

Found at the base of the pubic bone, within the rectus sheath, anterior to the rectus abdominis muscle.

Rectus abdominis

Flexion of the spine

move the body between the ribcage and the pelvis.

Transversus abdominus

postural support and help contain and support the organs inside the trunk. It's also a main core muscle that supports the lumbopelvic region.

located between the ribs and pelvis, and wrapping around the trunk from front to back.

Internal oblique

The internal obliques work with the external obliques to help the trunk twist and turn. They also help with exhaling and stabilizing the spine.

The internal obliques are located on the sides of the trunk, just inside the hip bones, and on top of the external obliques.

External oblique

The external oblique's primary function is to rotate the trunk from side to side. It also helps stabilize the core, move the spine, and assist with breathing.

The external oblique is one of the outermost abdominal muscles, located on the sides of the abdomen, and sits on top of the internal obliques.

Fascia

Scarpa

allow for smooth movement, protect the underlying organs, provide structural support to the abdominal wall, role in maintaining fluid balance and tissue pressure in the region.

Scarpa's fascia is a thin membrane of connective tissue located in the lower abdomen and anterior abdominal wall:

Intermediate

Abdominal

attaches, stabilizes, encloses, and separates muscles and other internal organs.

The TLF supports the lower back, helps maintain spinal alignment, and protects the underlying muscles and spinal structures. It also contains nerve endings that help with proprioception, the body's ability to sense its position and movement.

Located on either side of the lumbar vertebrae, the TLF is most prominent in the upper lumbar region.

Camper

Extends from the xiphoid process to the inguinal ligaments, and past the pubic symphysis

Protects the abdominal organs, insulates to maintain a constant temperature, and separates the skin from the muscles

Posterior Abdominal Wall

Lymphatics

deep

Iliac

Follows the deep circumflex iliac artery and drains into the external iliac nodes

Lumbar

Follows the lumbar arteries and drains into the lateral aortic nodes

super

Follow the superficial circumflex blood vessels in the lumbar and iliac regions

Inferior vena cava

A large vein that receives venous drainage from all structures below the diaphragm. It's located on the posterior abdominal wall, to the right of the abdominal aorta and in front of the vertebral column.

Abdominal aorta

T12

The abdominal aorta is a large blood vessel that runs along the posterior abdominal wall, supplying blood to the abdomen and other parts of the body:

Muscles

Quadratus lumborum

The quadratus lumborum (QL) muscle is innervated by the subcostal nerve (T12) and the first three nerves of the lumbar plexus (L1-L3):

extensor of the lumbar spine, a stabilizer of the lumbar area, capable of pelvic tilting laterally and capable of acting as an inspiratory accessory muscle.

Iliacus

femoral nerve (L2–L4).

flexes and rotates the thigh bone

Psoas major

Hip flexion and external rotation

T12–L5.

L1-L4 spinal nerves and sometimes includes T12

The nerves of the posterior abdominal wall primarily originate from the lumbar plexus

Fasica

Thoracolumbar

The TLF spans the length of the back, from the neck to the sacrum. It's most developed in the lumbar region.

The TLF has three layers: anterior, middle, and posterior. The posterior layer extends from the neck to the loin, while the anterior and middle layers are limited to the lumbar region.

Psoas

The psoas fascia is a thick layer of connective tissue that covers the psoas major muscle in the posterior abdominal wall:

Abdominal Viscera
Kidney

Glands

Produce hormones that control many important body functions, including blood pressure, blood sugar, metabolism, and the body's response to stress

Afferent

These nerves travel from the kidney to the dorsal root ganglia along the spinal cord. The least splanchnic nerve is the primary afferent signaling nerve from the kidney to the brain.

Efferent

These nerves are sympathetic and originate from the neuraxis.

regulate renal function, including sodium reabsorption, glomerular filtration, and renin release.

Renal veins

carry filtered blood from the kidneys to the heart:

Renal arteries

supply oxygenated blood to the kidneys, adrenal glands, and ureters

Minor Calyces

Major Calyces

Renal pyramids

Renal pelvis

Renal hilum

remove waste products from the blood and produce urine. control blood pressure.

Pancreas

sympathetic innervation from the greater and lesser splanchnic nerves (T5-T12).

The pancreas receives involuntary innervation via the autonomic nervous system (ANS). Its parasympathetic innervation originates from the vagus nerve (CN X)

gastroduodenal

A small vessel that supplies blood to the head of the pancreas, the pylorus, and the proximal part of the duodenum.

superior mesenteric

A major blood vessel in the digestive system that supplies oxygenated blood to the pancreas and the lower parts of the intestine.

Transverse pancreatic artery

Also known as the inferior pancreatic artery, it supplies the pancreatic tail and body. It originates from the proximal splenic artery.

Dorsal pancreatic artery

A branch of the splenic artery that supplies the pancreas. It runs along the posterior margin of the pancreas and divides into left and right branches.

Greater pancreatic artery

The largest blood vessel that supplies oxygenated blood to the pancreas. It originates from the splenic artery.

Ducts

Accessory pancreatic

secondary drainage system for the main pancreatic duct, which can help reduce pressure and prevent acute pancreatitis.

Main pancreatic

drains pancreatic fluid from the pancreas, which contains digestive enzymes and fluids that help break down food.

Parts

Tail

Neck

Head

Endocrine

produce and release hormones that regulate blood sugar levels:

Exocrine

secretion of digestive enzymes, ions and water into the duodenum

Spleen

The vagus nerve (CN X) provides parasympathetic innervation to the spleen.

The celiac plexus provides sympathetic innervation to the spleen.

Splenic artery

supplies oxygenated blood to the spleen, stomach, and pancreas:

Splenic vein

carries blood from the spleen, pancreas, and part of the stomach to the liver

located in the upper left quadrant of the abdomen, behind the stomach and under the left ribs

Stores and filters blood

Gall Bladder

Location

RUQ

gastrointestinal organ located within the right hypochondrial region of the abdomen.

Stores bile

Liver

Parasympathetic nerves:

Originate in the dorsal motor nucleus of the vagus nerve in the brainstem.

Sympathetic nerves

Originate in the celiac and superior mesenteric ganglia, which receive pre-ganglionic neurons from the spinal cord.

Hepatic portal vein

a vein conveying blood to the liver from the spleen, stomach, pancreas, and intestines.

Left hepatic vein

Located between the left medial and left lateral sectors

Middle hepatic vein

Located between the right anterior sector and segment IV

Right hepatic vein

Located between the right anterior and right posterior sectors

Lobes

Caudate

between the left and right lobes, and in an anterior and superior position

Quadrate

Located on the inferior surface of the right lobe

Smaller than the right lobe

The largest lobe of the liver

Visceral

posteroinferior surface that faces the abdominal organs and other adjacent structures

Diaphragmatic

fits under the vault of the diaphragm which in front separates it on the right from the sixth to the tenth ribs and their cartilages, and on the left from the seventh and eighth costal

filters all of the blood in the body and breaks down poisonous substances, such as alcohol and drugs

Large Intestine

Cecum

connects the small intestine to the colon

Features

Omental Appendices

made of fat and the peritoneum, a serous tissue that lines the abdominal wall and covers most abdominal organs

Teniae Coli

Shorten the colon wall to create haustra

Run the length of the ascending, transverse, descending, and sigmoid colons

Haustra

slow down the movement of digested food through the colon

Pelvic

controls the lower part of the GI tract, including the rectum and anus

Vagus

regulates tone and volume in the large intestine

Veins

Inferior mesenteric vein

Drains the descending colon and sigmoid colon

Superior mesenteric vein

Drains the ascending colon, transverse colon, and ileocolic vein

inferior mesenteric artery (IMA)

Rectum

responsible for storing feces and then moving it toward your anus

Appendix

attached to the large intestine

LRQ

Colon

Sigmoid

Usually in the pelvis, but can become displaced into the abdominal cavity

Stores fecal matter until it's ready to leave the body

Transverse

Between the right and left colic flexures, usually at the level of the 10th rib

left side of the body, between the transverse colon and sigmoid colon

runs superiorly on the right side of the abdomen from the right iliac fossa to the right lobe of the liver

Right side of the abdomen

forming and propelling feces toward the rectum

producing and absorbing vitamins

absorbing water and electrolytes

Small Intestine

Superior mesenteric vein (SMV)

Drains blood from the small intestine

Superior mesenteric artery (SMA)

supplies oxygenated blood

Auerbach's myenteric plexus

sympathetic and parasympathetic

Meissner's plexus

parasympathetic input

Ileum

RLQ

receives blood supply from the superior mesenteric artery

contains finger-like projections called villi that increase the surface area for nutrient absorption

has a mucosa (inner lining), submucosa, muscularis externa (muscle layer), and serosa (outer layer)

Jejunum

LUQ

Attached to a long mesentery, allowing for mobility within the abdominal cavity

circular folds in its submucosa called plicae circulares

Duodenum

Ascending

Ligament of Treitz

anchors the duodenum

L2-L3

Inferior

L3

Descending

Ampulla of Vater

Where the pancreatic and bile ducts meet to release digestive juices into the small intestine

Major duodenal papilla

allows bile and pancreatic enzymes to flow into the duodenum

L1-L3

Superior

L1

break down food, absorb nutrients the body needs, and excrete unnecessary components

Stomach

Anatomy

Curvatures

Lesser

Greater

Sections

Cardia

Fundus

Body

Pyloric

Vessels

Arterial

Celiac Trunk

Gastric

Left

supplies the lower esophagus and part of the stomach

Short

supply blood to the fundus and proximal body of the stomach, including the cardiac orifice

Posterior

Supplies blood to the superior and posterior regions of the stomach, near the border of the cardia and fundus

Right

supplies blood to the lesser curvature of the stomach

Venous

Short gastric

Drain into splenic vain

L & R gastric veins

Drain into portal vein

Nerves

Parasympathetic

Sympathetic

Greater splanchnic nerve

T6-T9

Cardiac plexus

influences gastric function by regulating motility and acid secretion in the stomach

Function

Churns the food to help break it down mechanically and chemically

Esophagus

Passes through the thoracic cavity and into the abdomen

Neuro Vasculature

The vagus nerve is the primary motor nerve of the esophagus

Innervated by the sympathetic and parasympathetic divisions of the autonomic nervous system

Structure

Adventitia (outer connective tissue layer)

Muscularis propria (muscle layer with inner circular and outer longitudinal fibers)

Submucosa (connective tissue layer)

Mucosa (inner lining)

Functions

Vomiting, eructation, and the gag reflex

Transport food and liquids from the mouth to the stomach

Prevent food and liquids from entering the windpipe or nasal cavity