Introductory Anatomy
of Digestive System
NYUNDO Martin, MD, MMed (Surgeon)
Lecturer
Dpt of Surgery and Dpt of Clinical Anatomy
FACMED-NUR
General considerations
 Digestive system is a series of hollow organs
joined in a long, twisting tube from the
mouth to the anus and other organs that help
the body break down and absorb food
►The main organs are: Mouth and pharynx,
Oesophagus Stomach, Small and Large
intestines,Appendix and Anus
► Accessory organs: Salivary glands, Liver,
Gallbladder, Pancreas
General considerations cont’d
 The gastrointestinal tract has a uniform general histology.The
GI tract can be divided into 4 concentric layers:

Mucosa is the innermost layer; this layer comes in direct
contact with the food (or bolus), and is responsible for
absorption and secretion, important processes in digestion.

Submucosa

Muscularis externa (the external muscle layer)

Adventitia or serosa
 Accessory organs:

The liver secretes bile into the small intestine via the bile
duct, employing the gallbladder as a reservoir. Apart from
storing and concentrating bile, the gallbladder has no other
specific function.

The pancreas secretes an isosmotic fluid containing
bicarbonate, which helps neutralize the acidic chyme, and
several enzymes into the small intestine. Both of these
secretory organs aid in digestion
General considerations cont’d
 Abdomen

The abdomen is the part of the trunk between the thorax and the pelvis

It is a flexible, dynamic container, housing most of the organs of the
digestive system and part of the urogenital system.

Containment of the abdominal organs and their contents is provided by:




musculoaponeurotic walls anterolaterally,
diaphragm superiorly,
muscles of the pelvis inferiorly,
lumbar vertebral column in the posterior.

The abdomen encloses and protects its
contents while allowing the flexibility between the
more rigid thorax and pelvis required by
respiration, posture, and locomotion.

Through voluntary or reflexive contraction, its
muscular roof, anterolateral walls, and floor can
raise internal (intra-abdominal) pressure to aid
expulsion from the abdominopelvic cavity or from
the adjacent thoracic cavity, expulsion of air from
the thoracic cavity (lungs and bronchi) or of fluid
(e.g., urine or vomitus), flatus, feces from the
abdominopelvic cavity.
General considerations cont’d
 Peritoneum and Peritoneal Cavity

The peritoneum is a continuous, glistening and slippery transparent
serous membrane. It lines the abdominopelvic cavity and invests
the viscera.

The peritoneum consists of two continuous layers: the parietal
peritoneum, which lines the internal surface of the abdominopelvic
wall, and the visceral peritoneum, which invests viscera such as the
stomach and intestines.

The peritoneal cavity is a potential space of
capillary thinness between the parietal and
visceral layers of peritoneum.

It contains no organs but contains a thin film of
peritoneal fluid, which is composed of water,
electrolytes, and other substances derived from
interstitial fluid in adjacent tissues.

Peritoneal fluid lubricates the peritoneal surfaces,
enabling the viscera to move over each other without
friction and allowing the movements of digestion.



In addition to lubricating the surfaces of the viscera, the
peritoneal fluid contains leukocytes and antibodies that
resist infection.
Lymphatic vessels absorb the peritoneal fluid.
The peritoneal cavity is completely closed in males;
however, there is a communication pathway in females
to the exterior of the body through the uterine tubes,
uterine cavity, and vagina. This communication
constitutes a potential pathway of infection from the
exterior.
General considerations cont’d
 Diaphragm

The diaphragm is a double-domed
musculotendinous partition separating
the thoracic and abdominal cavities.

Its mainly convex superior surface faces
the thoracic cavity, and its concave
inferior surface faces the abdominal
cavity.

The diaphragm is the chief muscle of inspiration.

It descends during inspiration; however, only its
central part moves because its periphery, as the
fixed origin of the muscle, attaches to the inferior
margin of the thoracic cage and the superior
lumbar vertebrae.

Orifices: vena caval foramen, esophageal hiatus
and aortic hiatus.
Esophagus
 First part of the digestive tract, that conveys food from the
pharynx to the stomach; it is about 25 cm long and 2 cm of
diameter.
 Is divided into three anatomical parts:

cervical (superior), thoracic (middle) and abdominal
(inferior).
 The esophagus:

Follows the curve of the vertebral column as it descends through
the neck and mediastinum in the median partition of the thoracic
cavity.

Has internal circular and external longitudinal layers of muscle.

In its superior third, the external layer consists of
voluntary striated muscle; the inferior third is
composed of smooth muscle, and the middle
third is made up of both types of muscle.

Passes through the esophageal hiatus in the
diaphragm,

Terminates by entering the stomach at the cardial
orifice of the stomach
Esophagus cont’d
 The esophagus has 2 sphincters:
 A sphincter is a narrowing caused by contracted (tightened) muscles.

These muscles remain contracted until the body sends a message for
the muscles to relax. When the muscles of the sphincter relax, this
then allows things to pass.

One sphincter is at the top of the esophagus. The other is where the
esophagus meets the stomach this is known as the gastro-esophageal
junction.

The lower sphincter controls the movement
of food into the stomach and prevents
stomach acid from going up into the
esophagus (gastro-esophageal reflux).

The lining of the esophagus is very
different to that of the stomach and
stomach acid will cause it to become
inflamed and sore if reflux does occur.
Stomach
 The stomach is the expanded part of the
alimentary tract between the esophagus
and the small intestine.
 It is specialized for the accumulation of
ingested food, which it chemically and
mechanically prepares for digestion and
passage into the duodenum.
 RESERVOIR


2-3L food in adult
30ml in newborn
 SHAPE VARIES




Individual build
Respiration
Contents
Position assumed by individual
 Parts of the Stomach:

Stomach cont’d
CARDIA



the part surrounding the cardial
orifice.
Orifice at 7th costal cartilage L
2-4 cm from median; at T10 or T11
level

FUNDUS - the dilated superior part
limited inferiorly by the horizontal plane
of the cardial orifice.

BODY - the major part of the stomach
between the fundus and the pyloric
antrum

PYLORUS (Pyloric part)


From notch - pyloric sphincter
At L1-L3 R median plane
Stomach cont’d
 The stomach has two curvatures:

Lesser curvature: forms the shorter
concave border of the stomach

Greater curvature: forms the longer convex
border of the stomach
 Two surfaces:


Anterior
Posterior
Stomach cont’d
Relations
 FUNDUS – diaphragm
 ANT SURFACE - diaphragm, liver L lobe & ant abd wall
 POST SURFACE - omental bursa & retroperitoneal
structures (kidney, pancreas, spleen.)
 SUPERIOR - lesser omentum & gastric vessels.
 INFERIOR - greater omentum & gastro-epiploic vessels.
Stomach cont’d
 Principles of blood supply

2 MAJOR ART SOURCES



VENOUS DRAINAGE


Coeliac trunk
Superior mesenteric
Follow arteries
LYMPHATIC DRAINAGE

Follow arteries
Stomach cont’d
 Venous drainage

FOLLOW ARTS


Drain into portal systems
R & L → portal vein

R GASTROEPIPLOIC (G-MENTAL) V →
superior mesenteric → may enter portal v
direct or join splenic v

L GASTROEPIPLOIC (G-MENTAL) → splenic
vein and its tributariess & short gastric vs.
Venous drainage
Lymphatic drainage

ALL LYMPH PASSES TO COELIAC GP of pre-aortic nodes

ALL LYMPH VS. ACCOMPANY ARTS along the 2 curves

4 MAJOR AREAS OF DRAINAGE

LESSER CURV


R PART GREATER CURV


Drains gastroepiploic & pyloric LNs
L PART GREATER CURV


Largest & drains to L gastric LNs
Drains pyl, gastoepip, & pancreticosplenic LNs
LESSER CURVE RELATED TO PYL

Drains to R gastric LNs
Lymphatics
 Common lymphatics
pathway:
Drain to coeliac LN →
Coeliac trunk →cisterna
chyli → Thoracic duct
Nerve supply
 PARASYMPATHETIC from ant and post vagal trunks
 SYMPATHETIC from coeliac plexus
 EFFERENT FIBRES from segments T6-T10
 VAGAL TRUNKS


Ant → lesser curve→ hepatic & duodenal branch
Post → lesser curve from post surface → coeliac →
coeliac plexus → post gastric branch
Nerve supply
3. SMALL INTESTINES
 Extent: stomach to colon
 Length: approximately 5m
 Parts



Duodenum
Jejunum
Ileum
DUODENUM
 The duodenum, the first and shortest (25 cm) part of the
small intestine, is also the widest and most fixed part.
 The duodenum pursues a C-shaped course around the
head of the pancreas.
 The duodenum begins at the pylorus on the right side and
ends at the duodenojejunal junction on the left side. ( Treitz
ligament)
 The junction usually takes the form of an acute angle, the
duodenojejunal flexure.
 Most of the duodenum is fixed by peritoneum to structures
on the posterior abdominal wall and is considered partially
retroperitoneal.
 The duodenum is divisible into four parts:

Superior (first) part: short (approximately 5 cm) and
lies anterolateral to the body of the L1 vertebra.

Descending (second) part: longer (7-10 cm) and
descends along the right sides of the L1-L3 vertebrae.

Horizontal (third) part: 6-8 cm long and crosses the L3
vertebra.

Ascending (fourth) part: short (5 cm) and begins at the
left of the L3 vertebra and rises superiorly as far as the
superior border of the L2 vertebra.
Superior or
First Part
1
2
Descending or
Second Part
4
3
Horizontal or
Third Part
Fourth or
Ascending Part
Duodenum blood supply
 The arteries arise from the celiac trunk and the
superior mesenteric artery. The celiac trunk, via
the gastroduodenal artery and its branch,
 The veins follow the arteries and drain into the
portal vein, some directly and others indirectly,
through the superior mesenteric and splenic
veins.
 The lymphatic vessels of the duodenum follow
the arteries.
CLINICALCORRELATES
 Duodenal ulcer

Usual located sup aspect - 1st part

When post, penetration may cause
bleeding (gastroduodenal art) or
erosion into head of pancreas

Ant ulcers may perforate into
peritoneum (peritonitis).
JEJUNUM & ILEUM

Jejunum: 2nd part of the small intestine, begins at the duodenojejunal
flexure at the Treitz ligament where the alimentary tract resumes an
intraperitoneal course.


Wider, thicker-walled than ileum
Mucous membrane thrown into circular folds with many longer villi

Ileum: third part of the small intestine, ends at the ileocecal junction, the
union of the terminal ileum and the cecum .

Together, the jejunum and ileum are 6 to 7 m long, the jejunum
constituting approximately two fifths and the ileum approximately three
fifths of the intraperitoneal section of the small intestine.
Jejunum and ileum
 Although no clear line of demarcation between
the jejunum and ileum exists, they have
distinctive characteristics that are surgically
important
 The jejunum and ileum can be distinguished by
ther color, feel and their complexity of arterial
arcades:
♦ Jejum: redder wall, thicker wall(feels full)
and simple arcades
♦ Ileum: thinner wall, (feels empty), multiple
arcades
 The mesentery is a fan-shaped fold of peritoneum that
attaches the jejunum and ileum to the posterior
abdominal wall
 The superior mesenteric artery supplies the jejunum and
ileum .
 The superior mesenteric vein drains the jejunum and
ileum.
 Specialized lymphatic vessels in the intestinal villi
 Blood vs. arrangement varies jej & ileum
MESENTERIC LYMPH
NODES
Large Intestine
 The large intestine is the site where water is absorbed
from the indigestible residues of the liquid chyme,
converting it into semisolid stool or feces that is stored
temporarily and allowed to accumulate until defecation
occurs.
 Extent

Ileocaecal junction to anus; about 1.5 m long
 Parts:




Caecum & vermiform appendix
Ascending, transverse & descending
Sigmoid
Rectum & anal canal
Small & large intestines
Large Intestine cont’d
 The large intestine can be distinguished from the small
intestine by:


Omental appendices: small, fatty, omentum-like
projections.
Three teniae coli:






(1) mesocolic, to which the transverse and sigmoid
mesocolons attach;
(2) omental, to which the omental appendices attach; and
(3) free (L. libera), to which neither mesocolons nor
omental appendices are attached.
Haustra: sacculations of the wall of the colon between
the teniae
A much greater caliber (internal diameter).
Mucosa

No villi, numerous mucus cells
Caecum
 Blind sac invested in peritoneum

8 cm W x 8 cm L, located in RIF
 Vermiform appendix
Attached to posteromedial wall
 Taenia coli converge on appendix

 Ileocaecal orifice
Opens on medial wall
 Surrounded by ileocaecal sphincter

Caecum & vermiform appendix
Vermiform appendix
 About 8 cm long
 Arises posteromedial aspect of caecum

About 3 cm below ileocaecal orifice
 Mesoappendix

Connects perit. to ileum
Appendicular art within this fold
 Commonly behind caecum or in pelvis
 Very mobile & its relations are variable

Position of the Appendix

A retrocecal appendix extends
superiorly toward the right colic
flexure and is usually free.

The appendix may project inferiorly
toward or across the pelvic brim.

The anatomical position of the
appendix determines the
symptoms and the site of muscular
spasm and tenderness when the
appendix is inflamed.

The base of the appendix lies deep
to a point that is one third of the
way along the oblique line joining
the right ASIS to the umbilicus (the
McBuney point on the
spinoumbilical line).
Ascending colon
 Lies R lateral flank
 Extent


Iliocaecal orifice to R colic flexure
15 cm long
 Peritoneum

Cover ant & both sides, fixing it to post wall
Relations of ascending
colon
 Post
Lower pole R kidney
 Iliohypogastric & ilioinguinal nerves

 Ant
Coils of small intestines
 Parts of greater omentum

Transverse colon
 50 cm long

At umbilicus level; largest & most mobile
 Extent


R - L colic flexures across the abd
L flexure more superior, acute angle & less
mobile than R flexure
 Sup: transverse mesocolon suspends it
 Inf: mesentery loops down to iliac crest,
adherent to post wall of omental bursa
Transverse colon
Relations of the transverse
colon
 Post R-L

2nd part duodenum, head of pancreas,
small intestine, L kidney
 Anterosuperiorly R-L

Liver, gb, stomach, greater omentum &
spleen
 Transv colon mesentery
Attaches to body of pancreas
 Continuous with parietal peritoneum

Descending colon
 Narrowest part of colon; L lateral flank
 Extent: Splenic flexure-LIF
 30 cm long
 Peritoneum cover ant & on both sides,
fixing it to post wall
 Flexure attached to diaphragm by
phrenico-colic ligament, that also
supports the spleen
Relations of descending
colon
 Post
Lower pole L kidney & diaphragm
 Quadratus lumborum, iliacus & psoas

 Peritoneal surfaces

In contact with coils of small intestines
Sigmoid colon
 LIF, pelvic brim - S3 ant
 40 cm long, varies in position
 Attached to pelvic wall by an inverted V-
shaped sigmoid mesentery
 Apex of V overlies L ureter, at bifurcation
of common iliac v & L sacroiliac joint
 Taenia coli terminate 15 cm from anus,
marking the recto-sigmoid junction
Relations of sigmoid colon
 Post

Lies on L ureter & common iliac vessels
 Sup

Covered by coils of small intestine
 Inf
Lies on urinary bladder in male
 Lies on uterus in female

Rectum
 12 cm long, pelvic & no mesentery
 Extent
Rectosigmoid (S3) - anorectal j
 Course: from S3 curves forward, loops
L as far as coccyx tip; widens inf. into a
rectal ampulla

Relations of the rectum
 Lat: coils of small int covered by peritoneum
 Inf: levator ani, coccyx & rectal vs
 Post: sup rectal art, S3, S4 & S5, symp
trunk, lat & median sacral vs lower part of
sacrum, coccyx
 In both sexes, upper ⅓ forms post wall of
rectovesical pouch in ♂,& rectouterine in ♀
 In ♂: sem vesicles, d deferens, bladder &
prostate; in ♀ post wall vagina & uterus
Anal canal
 4 cm long
 External & internal sphincters
 Internal
Involuntary (circular muscle coat)
 Upper 2/3 canal, innervated by pelvic
plexus; sympathetic stimulation
contracts muscle

Anal canal - cont…
 External - lower ⅓ of canal
Superficial - surrounds lower part;
attaches to anococcygeal body &
perineal body; inf. rectal n
 Deep - mid part of canal, levator ani
reinforces & essential in function

 Subcutaneous - thick ring of muscle
surrounding anal orifice
Blood supply of large intestine
Clinical correlates
 Appendicitis
 Cancer of large intestines
ACCESORY ORGANES
 Spleen

The spleen is an ovoid organ; varies considerably in
size, weight, and shape; however, it is usually
approximately 12 cm long and 7 cm wide.

The spleen is located in the left upper abdominal
quadrant or hypochondrium, where it receives the
protection of the lower thoracic cage

The diaphragmatic surface of the spleen is convexly
curved to fit the concavity of the diaphragm.

The anterior and superior borders of the spleen
are sharp and often notched, whereas its
posterior (medial) end and inferior border are
rounded.

It is relatively delicate and considered the most
vulnerable abdominal organ.

As the largest of the lymphatic organs, it
participates in the body's defense system as a
site of lymphocyte (white blood cell) proliferation
and of immune surveillance and response.
 The relations of the spleen are




Anteriorly, the stomach.
Posteriorly, the left part of the diaphragm,
Inferiorly, the left colic flexure.
Medially, the left kidney.
 The spleen contacts the posterior wall of the
stomach and is connected to its greater
curvature by the gastrosplenic ligament and to
the left kidney by the splenorenal ligament.
 These ligaments, containing splenic
vessels, are attached to the hilum of the
spleen on its medial aspect .
 The splenic hilum is often in contact with
the tail of the pancreas and constitutes
the left boundary of the omental bursa.
Splenic vessels
 The splenic artery is the largest branch
of the celiac trunk Between the layers of
the splenorenal ligament, the splenic
artery divides into five or more branches
that enter the hilum.
 The splenic vein is formed by several
tributaries that emerge from the hilum.
With the IMV and SMV form the portal
vein.
 The splenic lymphatic vessels leave the
lymph nodes in the splenic hilum and
pass along the splenic vessels to the
pancreaticosplenic lymph nodes
 The nerves of the spleen, derived from
the celiac nerve plexus, are distributed
mainly along branches of the splenic
artery, and are vasomotor in function
Pancreas
 The pancreas is an elongated,
accessory digestive gland that lies
retroperitoneally and transversely across
the posterior abdominal wall, posterior to
the stomach between the duodenum on
the right and the spleen on the left.
 The pancreas produces

An exocrine secretion (pancreatic juice
from the acinar cells) that enters the
duodenum through the main and
accessory pancreatic ducts.

Endocrine secretions (glucagon and insulin
from the pancreatic islets [of Langerhans])
that enter the blood.
 The pancreas is divided into four parts:
head, neck, body, and tail.

The head of the pancreas is the expanded
part of the gland that is embraced by the
C-shaped curve of the duodenum to the
right of the superior mesenteric vessels.
Pancreatic ducts
 The main pancreatic duct begins in the tail of
the pancreas and runs through the parenchyma
of the gland to the pancreatic head: here it turns
inferiorly and is closely related to the bile duct.
 Most of the time, the main pancreatic duct and
the bile duct unite to form the short, dilated
hepatopancreatic ampulla (of Vater), which
opens into the descending part of the
duodenum at the summit of the major duodenal
papilla.
 The sphincter of the pancreatic duct
(around the terminal part of the
pancreatic duct), the sphincter of the bile
duct (around the termination of the bile
duct), and the hepatopancreatic
sphincter (of Oddi); around the
hepatopancreatic ampulla are smooth
muscle sphincters that control the flow of
bile and pancreatic juice into the
duodenum.
BLOOD SUPPLY OF
PANCREAS
 The pancreatic arteries derive mainly from the
branches of the markedly tortuous splenic
artery, which form several arcades with
pancreatic branches of the gastroduodenal and
superior mesenteric arteries.
 The corresponding pancreatic veins are
tributaries of the splenic and superior
mesenteric parts of the portal vein; however,
most of them empty into the splenic vein.
 The pancreatic lymphatic vessels follow the blood
vessels.
 Most vessels end in the pancreaticosplenic lymph nodes,
that lie along the splenic artery. Some vessels end in the
pyloric lymph nodes.
 The nerves of the pancreas are derived from the vagus
and abdominopelvic splanchnic nerves passing through
the diaphragm.
 The parasympathetic and sympathetic fibers reach the
pancreas by passing along the arteries from the celiac
plexus and superior mesenteric plexus
LIVER
 The liver is the largest gland. It weighs approximately
1500 g and accounts for approximately 2.5% of adult
body weight.
 It extends into the left hypochondrium, inferior to the
diaphragm.
 Except for fat, all nutrients absorbed from the
gastrointestinal tract are initially conveyed first to the liver
by the portal venous system.
 In addition to its many metabolic activities, the liver stores
glycogen and secretes bile.
 Bile passes from the liver via the biliary
ducts;right and left hepatic ducts that join to
form the common hepatic duct, which unites
with the cystic duct to form the bile duct.
 The liver produces bile continuously; however,
between meals it accumulates and is stored in
the gallbladder, which also concentrates the
bile by absorbing water and salts. When food
arrives in the duodenum, the gallbladder sends
concentrated bile through the bile ducts to the
duodenum.
Surfaces, Peritoneal Reflections,
and Relationships of the Liver
 The liver has a convex diaphragmatic surface (anterior,
superior, and some posterior) and a relatively flat or even
concave visceral surface (posteroinferior),
 Anatomical Lobes of the Liver
 Externally, the liver is divided into two lobes and two
accessory lobes by the reflections of peritoneum from its
surface.

The essentially midline plane defined by the attachment
of the falciform ligament and the left sagittal fissure
separates a large right lobe from a much smaller left lobe
Biliary Ducts and
Gallbladder
 The biliary ducts convey bile from the liver to
the duodenum.
 Bile is produced continuously by the liver and
stored and concentrated in the gallbladder,
which releases it intermittently when fat enters
the duodenum. Bile emulsifies the fat, so that it
can be absorbed in the distal intestine.
 Bile Duct
 The
bile duct (formerly, common bile
duct) forms in the free edge of the lesser
omentum by the union of the cystic duct
and the common hepatic duct. The length
of the bile duct varies from 5 to 15 cm,
depending on where the cystic duct joins
the common hepatic duct.
Gallbladder
 The gallbladder (7-10 cm long) lies in the fossa
for the gallbladder on the visceral surface of the
liver.
 The pear-shaped gallbladder can hold up to 50
mL of bile. Peritoneum completely surrounds
the fundus of the gallbladder and binds its body
and neck to the liver.
 The hepatic surface of the gallbladder attaches
to the liver by connective tissue of the fibrous
capsule of the liver.
 The gallbladder has three parts:
 Fundus:
the wide end of the organ, projects
from the inferior border of the liver and is
usually located at the tip of the right 9th costal
cartilage in the MCL.
 Body: contacts the visceral surface of the
liver, the transverse colon, and the superior
part of the duodenum.
 Neck: narrow and tapered; directed toward
the porta hepatis; it makes an S-shaped bend
and joins the cystic duct.
 The cystic duct (3-4 cm long) connects
the neck of the gallbladder to the
common hepatic duct.
 The cystic duct passes between the
layers of the lesser omentum, usually
parallel to the common hepatic duct,
which it joins to form the bile duct.
Introductory Anatomy
of Respiratory System
NYUNDO Martin, MD,MMed (General
Surgeon)Lecturer
Dpt of Surgery and Dpt of Clinical Anatomy
FACMED-NUR
General considerations
 The respiratory system is made up of the organs involved in
respiration
 Respiration is the act of breathing
inhaling (inspiration) - taking in oxygen
 exhaling (expiration) - giving off carbon dioxide

 The respiratory system consists of the:

Nose, pharynx, larynx, trachea, bronchi and lungs

lungs
The pleura and airways
 The respiratory tract is most often discussed in terms of
upper and lower parts.
 The upper respiratory tract relates to the nasopharynx
and larynx whereas the lower relates to the trachea,
bronchi and lungs.
 Beginning at the larynx, the walls of the airway are
supported by C-shaped rings of hyaline cartilage.
 The sub-laryngeal airway constitutes the
tracheobronchial tree.
 The thorax includes the primary organs of the
respiratory and cardiovascular systems
 The thorax is the superior part of the trunk between
the neck and abdomen
 Commonly the term chest is used as a synonym for
thorax
 The thoracic cavity is divided into three major
spaces:

The central compartment, or mediastinum, houses the
conducting structures that make up the thoracic viscera,
except for the lungs

The lungs occupy the lateral compartments or pulmonary
cavities that lie on each side of the mediastinum. Thus the
majority of the thoracic cavity is occupied by the lungs,
 Parts of Respiratory system

Pharynx, Larynx

Trachea

Bronchi

Lungs
The trachea
 Located within the superior mediastinum, constitutes
the trunk of the tree
 It bifurcates at the level of the transverse thoracic
plane (or sternal angle) into main (primary) bronchi,
one to each lung, passing inferolaterally to enter the
lungs at the hila (hilum)
The trachea 2

Course


the trachea commences at the level of the cricoid cartilage in
the neck (C6)
It terminates at the level of the angle of Louis (T4/5) where it
bifurcates into right and left main bronchi
 Structure



The trachea is a rigid fibroelastic structure
Incomplete rings of hyaline cartilage continuously maintain the
patency of the lumen.
The trachea is lined internally with ciliated columnar
epithelium.
Trachea3
 Relations

Behind the trachea lies the oesophagus

The 2nd, 3rd and 4th tracheal rings are crossed
anteriorly by the thyroid isthmus
 Blood supply


the inferior thyroid
bronchial arteries
Bronchi
 The right main bronchus is shorter, wider and takes a more vertical
course than the left

The width and vertical course of the right main bronchus account
for the tendency for inhaled foreign bodies to preferentially impact
in the right middle and lower lobe bronchi.
 The left main bronchus enters the hilum and divides into a superior
and inferior lobar bronchus
 The right main bronchus gives off the bronchus to the upper lobe
prior to entering the hilum and once into the hilum divides into middle
and inferior lobar bronchi.
 the air:







enters the body through the nose or the mouth
travels down the throat through the larynx (voice box) and trachea
(windpipe)
goes into the lungs through tubes called main-stem bronchi
one main-stem bronchus leads to the right lung and one to the left
lung
in the lungs, the main-stem bronchi divide into smaller bronchi
and then into even smaller tubes called bronchioles
bronchioles end in tiny air sacs called alveoli
The bronchi and bronchopulmonary
segments
 Each lobar bronchus divides within the lobe into
segmental bronchi
 Each segmental bronchus enters a
bronchopulmonary segment
 Each bronchopulmonary segment is pyramidal in shape
with its apex directed towards the hilum

It is a structural unit of a lobe that has its own segmental
bronchus, artery and lymphatics.
 Beyond the direct branches of the lobar bronchi that is,
beyond the segmental bronchi are from 20 to 25
generations of branches that eventually end in
terminal bronchioles
 Each terminal bronchiole gives rise to several
generations of respiratory bronchioles,
 Each respiratory bronchiole provides 2-11 alveolar
ducts,
 Each of which gives rise to 5-6 alveolar sacs lined by
alveoli.
 The pulmonary alveolus is the basic structural
unit of gas exchange in the lung.

New alveoli continue to develop until about age 8
years, by which time there are approximately 300
million alveoli.
LUNGS
 The lungs are a pair of cone-
shaped organs made up of
spongy, pinkish-gray tissue.
Function
 What do lungs do?
 The
lungs are the vital organs of respiration
 Their main function is to oxygenate the blood by
bringing inspired air into close relation with the
venous blood in the pulmonary capillaries
 The lungs take in oxygen, which all cells throughout the
body need to live and carry out their normal functions
 The lungs also get rid of carbon dioxide, a waste
product of the body's cells.
 The lungs are separated from
each other by the mediastinum, an
area that contains the following:




heart and its large vessels
trachea (windpipe)
esophagus
lymph nodes
 The lungs are inside in a membrane
called the pleura.
 The pleural cavity:”the potential space
between the layers of pleura ”contains
a capillary layer of serous pleural fluid,
which lubricates the pleural surfaces
and allows the layers of pleura to slide
smoothly over each other during
respiration.

Its surface tension also provides the
cohesion that keeps the lung surface in
contact with the thoracic wall;
consequently, the lung expands and
fills with air when the thorax expands
while still allowing sliding to occur,
much like a layer of water between two
glass plates.
 Description of the lungs:

Lobes marked by fissures:


The right lung has three lobes
The left lung has two lobes.

Apex

Basis (diaphragmaic surf)

Border (ant, post and inf)

Surfaces ( costal, mediastinal and
diaphragmatic)
Relations of the lungs
Heart
 Thoracic Aorta
 Esophagus
 Pulmonary artery
 Pulmonary veins
 Sup and inf vena cava

CLINICAL CORRELATES
 Infections: bronchitis
 Pneumothorax:
 Entry of air into the pleural cavity, resulting from a penetrating
wound of the parietal pleura
 Fractured ribs may also tear the visceral pleura and lung, thus
producing pneumothorax.
 Hydrothorax : The accumulation of a significant amount of
fluid in the pleural cavity may result from pleural effusion
(escape of fluid into the pleural cavity).

Hemothorax



With a chest wound, blood may also enter the pleural
cavity.
Hemothorax results more commonly from injury to a
major intercostal or internal thoracic vessel than from
laceration of a lung.
Hemopneumothorax :

If both air and fluid, (if the fluid is blood) accumulate in
the pleural cavity, an air fluid level or interface (sharp
line, horizontal regardless of the patient's position,
indicating the upper surface of the fluid) will be seen
on a radiograph.

Thoracentesis:



Sometimes it is necessary to insert a hypodermic needle
through an intercostal space into the pleural cavity to
obtain a sample of fluid or to remove blood or pus .
To avoid damage to the intercostal nerve and vessels,
the needle is inserted superior to the rib, high enough to
avoid the collateral branches.
Thoracic drainage: chest tube


LUNG CANCER

Lung cancer usually starts in the lining of the bronchi, but can also begin in other
areas of the respiratory system, including the trachea, bronchioles, or alveoli.

Lung cancers are believed to develop over a period of many years

Nearly all lung cancers are carcinomas, a cancer that begins in the lining or covering
tissues of an organ.
What are the risk factors for lung cancer?

A risk factor is anything that increases a person's chance of getting a disease such as cancer

Different cancers have different risk factors. Several risk factors make a person more likely to
develop lung cancer:


Smoking is the leading cause of lung cancer, with more than 90 percent of lung cancers
thought to be a result of smoking.
Additional risk factors include:

.
second-hand smoke - breathing in the smoke of others.
Introductory Anatomy
of Urinary System
NYUNDO Martin, MD, MMed (Surgeon)
Lecturer
Dpt of Surgery and Dpt of Clinical Anatomy
FACMED-NUR
General considerations
 The urinary system, with other organs regulates
the volume and composition of the interstitial
fluid.
 The urinary system consists of the following
organs:




Two kidneys,
a single, midline urinary bladder,
two ureters, which carry urine from the kidneys to
the urinary bladder
a single urethra, which carries urine from the
bladder to the outside of the body
KIDNEYS
 The kidneys are the major excretory organs of the body;
they remove most waste products, many of which are
toxic, from the blood and play a major role in controlling
blood volume, the concetration of ions in the blood, the
pH of the blood, red blood cell production and vitamin D
metabolism.
 The skin, liver, lungs and intestines eliminate some waste
products, but if kidneys fail to function, other excretory
organs cannot adequately compensate.
KIDNEYS
 The kidneys are bean shaped purplish-brown organs located
below the ribs toward the middle of the back.
 The lie on the posterior abdominal wall behind the peritoneum
 The superior pole of each kidney is protected by the rib cage,
and the right kidney is slightly lower than the left because of
the presence of the liver superior to it.
 Each kidney measures about 11cm long, 5 cm wide and
3cm thick and weighs about 130g
 On the medial side of each kidney is a small area called the
hilium, where the renal artery and nerves enter and the
renal vein and the ureter exit
 The hilium opens into a cavity called the renal sinus which
contains fat and connective tissue
 The kidney is divided into an outer cortex and an inner
medulla that surrounds the renal sinus
 The medulla cosists of a number of cone shaped,
renal pyramids, which appear triangular when
seen in a longitudinal section of the kidney
 The base of each pyramid is located at the
boundary between the cortex and the medulla, and
the tips of the pyramids, the renal papillae are
pointed toward the center of the kidney.
 Funnel shaped structures called minor calyces
surround the renal papillae
 The minor calyces from several pyramids join together
to form larger funnels called major calyces
 There are 8 to 20 minor calyces and 2 or 3 major
calyces per kidney
 This major calyces converge to form an anlarged
channel called the renal pelvis, which is located in the
renal sinus
 The renal pelvis then narrows to form a small
tube, the ureter which exits the kidney and
connects to the urinary bladder
 Urine formed within the pyramids passes from
the renal papillae into the minor calyces, from
there urine moves into the the major calyces,
collects in the renal pelvis and exits the kidney
through the ureter.
Nephron
 The basic histological and functional unit of the kidney is
the nephron, which consists of an enlarged terminal
end called Bowman’s capsule, a proximal
convuluted tubule, a loop of Henle and distal
convuluted tubule.
 The distal convuluted tubule empties into a collecting duct,
which carries the urine from the cortex of the kidney to the
calyces.
 The Bowman’s capsule and both convoluted
tubules are in the renal cortex
 The collecting tubules and parts of the loops of
Henle enter the renal medulla.
 There are about 1.300.000 nephrons in each
kidney and one third of them must be functional to
ensure survival.
BLOOD SUPPLY
 Renal artery from the abdominal aorta
 Renal vein exits the kidney and connects to the
inferior vena cava
Ureters and urinary bladder
 Ureters


narrow tubes that carry urine from the kidneys to the
bladder.
The ureters extend inferiorly and medially from the renal
pelvis at the renal hilium to reach the urinary bladder.

Muscles in the ureter walls continually tighten and relax
forcing urine downward, away from the kidneys.

If urine backs up, or is allowed to stand still, a kidney
infection can develop. About every 10 to 15 seconds,
small amounts of urine are emptied into the bladder
from the ureters.
 The urinary bladder

is a hollow muscular container that lies in the
pelvic cavity just posterior to the symphysis pubis.

In male it is just anterior to the rectum and in the
female it is just anterior to the vagina znd inferior
and anterior to the uterus.

The size of the bladder depens on the presence or
absence of the urine.
 The ureters enter the bladder inferiorly
on its posterolateral surface, and the
urethra exits the bladder inferiorly and
anteriorly
 The traingular area of the bladder wall
between the two ureters posteriorly and
the urethra anteriorly is called trigone;
this region differs histologically from the
rest of the bladder wall and does not
expand during bladder filling
 At the junction of the urethra with the bladder,
smooth muscle of the bladder forms the internal
urinary sphincter
 The external urinary sphincter is skeletal
muscle that surrounds the the urethra as the
urethra extends through the pelvic floor
 The sphincters control the flow of urine through
the urethra.
 In the male the urethra extends to the
end of the penis, where it opens to the
outside
 The female urethra is much shorter than
the male urethra and opens into the
vestibule anterior to the vaginal opening
Facts about urine
 Adults pass about a quart and a half of urine each day,
depending on the fluids and foods consumed.
 The volume of urine formed at night is about half that
formed in the daytime.
 Normal urine is sterile. It contains fluids, salts and waste
products, but it is free of bacteria, viruses and fungi.
 The tissues of the bladder are isolated from urine and
toxic substances by a coating that discourages bacteria
from attaching and growing on the bladder wall
Introductory Anatomy
of Reproductive System
NYUNDO Martin, MD, MMed (Surgeon)
Lecturer
Dpt of Surgery and Dpt of Clinical Anatomy
FACMED-NUR
 Animals’ reproductive systems can be
divided into the internal reproductive
organs and the external genitalia. The
gonads are the actual organs that
produce the gametes. In the male,
testes (singular = testis) produce sperm
cells, and in the female, ovaries make
ovules (eggs).
Male Reproductive System
 Testis

. Sperm cells are produced in the testes located
in the scrotum. Normal body temperature is too
hot thus is lethal to sperm so the testes are
outside of the abdominal cavity where the
temperature is about 2° C (3.6° F) lower..
 Epididymis
 From there, sperm are transferred to the, coiled
tubules also found within the scrotum, that store
sperm and are the site of their final maturation.
 Vas deferens (plural = vasa deferentia)

In ejaculation, sperm are forced up int the
vas deferens From the epididymis, the vas
deferens goes up, around the front of, over
the top of, and behind the bladder.
 The ends of the vasa deferentia, behind
and slightly under the bladder, are called
the ejaculatory ducts.
 The seminal vesicles are also located behind
the bladder. Their secretions are about 60% of
the total volume of the semen (= sperm and
associated fluid) and contain mucus, amino
acids, fructose as the main energy source for
the sperm, and prostaglandins to stimulate
female uterine contractions to move the semen
up into the uterus.
 The seminal vesicles empty into the ejaculatory
ducts. The ejaculatory ducts then empty into the
urethra (which, in males, also empties the
urinary bladder).
 PROSTATE
 The initial segment of the urethra is surrounded by
the prostate gland (note spelling!). The prostate is
the largest of the accessory glands and puts its
secretions directly into the urethra. These
secretions are alkaline to buffer any residual urine,
which tends to be acidic, and the acidity of the
woman’s vagina.
 The prostate needs a lot of zinc to function
properly, and insufficient dietary zinc (as well as
other causes) can lead to enlargement which
potentially can constrict the urethra to the point of
interferring with urination.
 The bulbourethral glands or Cowper’s
glands are the third of the accessory
structures. These are a small pair of glands
along the urethra below the prostate. Their fluid
is secreted just before emission of the semen,
thus it is thought that this fluid may serve as a
lubricant for inserting the penis into the vagina,
but because the volume of these secretions is
very small, people are not totally sure of this
function.
 Penis

The urethra goes through the penis.

In humans, the penis contains three cylinders of spongy, erectile
tissue (corpus cavemosum and corpus spongiosum) . During
arousal, these become filled with blood from the arteries that supply
them and the pressure seals off the veins that drain these areas
causing an erection, which is necessary for insertion of the penis into
the woman’s vagina.

The head of the penis, the glans penis, is very sensitive to stimulation.

In humans, as in other mammals, the glans is covered by the foreskin
or prepuce, which may have been removed by circumcision.
Female Reproductive
System
 Ovary
ovules are produced in the ovaries,
 Each ovule is released into the abdominal
cavity near the opening of one of the
oviducts or Fallopian tubes.

Uterus
 The uterus is a hollow, thick-walled, pear-shaped




muscular organ in the female reproductive system.
During pregnancy the uterus expands to accommodate a
developing embryo.
It is located between the urinary bladder in front and the
rectum behind, and sits above the vagina.
The lower narrow portion of the uterus is called the cervix
and it protrudes downward into the opening of the vaginal
canal.
The vaginal canal extends downward to the external
female genitalia.
 The uterine tubes, or Fallopian tubes, extend
from either side of the uterus and act as a
channel for eggs from the ovary to travel to the
uterus. When an egg is fertilized (joined with
sperm), it becomes embedded in the wall of the
uterus (whose lining becomes thickened) where
the fertilized egg grows into an embryo and
later a fetus.
 If an egg is not fertilized, the thickened uterine
lining sloughs off in a process known as
menstruation.
 The uterus has thick, muscular walls
and is very small.
 In a nulliparous woman, the uterus is
only about 7 cm long by 4 to 5 cm wide,
but it can expand to hold a 4 kg baby.
 The lining of the uterus is called the
endometrium, and has a rich capillary
supply to bring food to any embryo that
might implant there.
Vagina
 The vagina
 is a relatively-thin-walled chamber
 It servs as a repository for sperm (it is where the penis is
inserted), and also serves as the birth canal. Note that,
unlike the male, the female has separate opening for the
urinary tract and reproductive system.
 These openings are covered externally by two sets of
skin folds. The thinner, inner folds are the labia minora
and the thicker, outer ones are the labia majora.
 The labia minora contain erectile tissue like that in the
penis, thus change shape when the woman is sexually
aroused.
 The opening around the genital area is called the vestibule.
 There is a membrane called the hymen that partially covers
the opening of the vagina. This is torn by the woman’s first
sexual intercourse (or sometimes other causes like injury or
some kinds of vigorous physical activity).
 In women, the openings of the vagina and urethra are
susceptible to bacterial infections if fecal bacteria are wiped
towards them. Thus, while parents who are toilet-training a
toddler usually wipe her from back to front, thus “imprinting” that
sensation as feeling “right” to her, it is important, rather, that
that little girls be taught to wipe themselves from the front to the
back to help prevent vaginal and bladder infections. Older girls
and women who were taught the wrong way need to make a
conscious effort to change their habits.
 At the anterior end of the labia, under the pubic
bone, is the clitoris, the female equivalent of
the penis. This small structure contains erectile
tissue and many nerve endings in a sensitive
glans within a prepuce which totally encloses
the glans.
 This is the most sensitive point for female
sexual stimulation, so senstiive that vigorous,
direct stimulation does not feel good.