Transcript Airgas template - Morgan Community College

Essentials of Pathophysiology
CHAPTER 30
DISORDERS OF HEPATOBILIARY AND
EXOCRINE PANCREAS FUNCTION
PRE LECTURE QUIZ TRUE/FALSE
F

F

F

T

F

The liver does not play a role in glucose homeostasis.
Jaundice results from an abnormally high accumulation
of bile in the blood.
Hepatitis, inflammation of the liver, is of bacterial origin.
Cholelithiasis, or gallstones, is caused by precipitation
of substances contained in bile, mainly cholesterol and
bilirubin.
Chronic pancreatitis is a severe, life-threatening
disorder associated with the escape of activated
pancreatic enzymes into the pancreas and surrounding
tissues.
PRE LECTURE QUIZ

The __________ cells are capable of removing and
phagocytizing old and defective blood cells, bacteria,
and other foreign material from the portal blood as it
flows through the sinusoid.

One of the metabolic functions of the liver is the
conversion of ammonia, which is produced by
deamination of amino acids, into __________.

Pruritus is the most common presenting symptom in
persons with cholestasis, probably related to
increased bile __________ in the blood.

Hepatitis __________ is the most common cause of
chronic hepatitis, cirrhosis, and hepatocellular cancer
in the world.

__________ represents the end stage of chronic liver
disease in which much of the functional liver tissue
has been replaced by fibrous tissue.
C
Cirrhosis
Kupffer
salts
urea
SYSTEM
SYSTEM INTERACTION
LIVER STRUCTURE

Blood from
hepatic portal
vein and hepatic
artery mix in
sinusoids

The sinusoids
empty into central
veins, which send
the blood to the
hepatic vein and
inferior vena cava
LIVER STRUCTURE(CONT.)


Hepatic cells lie
along the
sinusoids and
pick up
chemicals from
the blood
They modify the
blood’s
composition
LIVER STRUCTUR E(CONT.)


At the back end
of each hepatic
cell, bile is
released into a
canaliculus
The bile is carried
to the bile duct
and then to the
gallbladder
LIVER STRUCTURE (CONT.)


Many sinusoids
come together to
empty into one
vein
The section of the
liver emptying into
one vein is a
lobule
QUESTION
Tell whether the following statement is true or
false.
The gallbladder stores bile that has been
produced by the liver.
ANSWER
True
Rationale: The liver makes bile and secretes it
into the small intestine via the common bile
duct. Excess bile is stored in the gallbladder,
where it also enters the small intestine through
the common bile duct when it is needed.
METABOLIC FUNCTIONS OF THE LIVER

Carbohydrate, protein, and lipid metabolism
 Sugars  stored as glycogen, converted to
glucose, used to make fats
 Proteins  synthesized from amino acids;
ammonia made into urea
 Fats  oxidized for energy, synthesized,
packaged into lipoproteins
METABOLIC FUNCTIONS OF THE LIVER (CONT.)


Drug and hormone metabolism
 Biotransformation into water-soluble forms
 Detoxification or inactivation
Bile production
QUESTION
Which of the following substances does bile
make more susceptible to digestive enzymes?
a. Carbohydrate
b. Protein
c. Fat
d. All of the above
ANSWER
Fat
Rationale: Bile (produced in the liver) emulsifies
fat molecules so that they are easier to digest.
An emulsion is a mixture of two immiscible
(unblendable) substances, in this case bile and
fat.
c.
SCENARIO
Mr. M had a donut for breakfast.
Question:
 Explain how the sugar in the donut left his
small intestine and ended up as fat in his
carotid artery, giving the:
 Anatomical structures
 Chemical processes
 Hormones that controlled them
SCENARIO
Ms. B was prescribed an oral medication for her
skin problem. She took it twice a day.
 The day after she started the medication, Ms. B
drank wine with a friend right after taking the
prescribed dosage
Question:
 Ms. B got terribly ill. Why? She said, “I drink that
kind of wine all the time.”
LIVER FAILURE

Hematologic disorders as the liver fails the spleen
takes over some of the function of the liver
 Anemia- due to splenomegaly

Thrombocytopenia- due to splenomegaly

coagulation defectsleukopenia due to splenomegaly
As your spleen grows larger, it begins to filter
normal red blood cells as well as abnormal ones,
reducing the number of healthy cells in your
bloodstream. It also traps too many platelets.
Eventually, excess blood cells and platelets can
clog your spleen, interfering with its normal
functioning.


LIVER FAILURE

Endocrine disorders
 Fluid retention, hypokalemia, Lack of metabolism of
aldosterone, too much remains in the system
 disordered sexual functions
 Which hormones would cause these endocrine
disorders? Failure of Cholesterol/Steroid formation
LIVER FAILURE (CONT.)


Skin disorders
 Jaundice, red palms, spider nevi
Hepatorenal syndrome
Deteriorating liver function is believed to cause changes in the
circulation altering blood flow in the kidneys. The renal failure of
HRS is a consequence of these changes in blood flow
Azotemia, increased plasma creatinine, oliguriadecreased production of urine
Hepatic encephalopathy- caused by accumulation in the


bloodstream of toxic substances that are normally removed by
the liver

Asterixis, confusion, coma, convulsions

Asterixis : An uncontrollable flapping of the hands that
becomes noticeable when patients stretch out their arms,
palms out, as if stopping traffic.
JAUNDICE IN A PERSON WITH HEPATITIS A
QUESTION
What causes jaundice?
a. Increased bilirubin levels
b. Anemia
c. Thrombocytopenia
d. Leukopenia
ANSWER
a. Increased bilirubin levels
Rationale: Erythrocytes are normally broken down
in the spleen at the end of their life span. The
end product of RBC metabolism is bilirubin.
Bilirubin is sent to the liver to be metabolized;
if the liver is not functioning properly, the
bilirubin accumulates and causes jaundice (an
abnormal yellowing of the skin and mucous
membranes).
HEPATITIS






Viral hepatitis
Hepatitis A virus (HAV)
Hepatitis B virus (HBV)
Hepatitis B–associated delta virus (HDV)
Hepatitis C virus (HCV)
Hepatitis E virus (HEV)
DISCUSSION
Which hepatitis viruses are most likely to be
the problem in:

An asymptomatic drug abuser?

A nursing student who has spent the last two E
months volunteering in an orphanage in Mali?

An infant whose mother has hepatitis?
C
B
CHRONIC VIRAL HEPATITIS



Caused by HBV, HCV, and HDV
Principal worldwide cause of chronic liver
disease, cirrhosis, and hepatocellular cancer
Chief reason for liver transplantation in adults
ALCOHOLIC LIVER DISEASE

Fatty liver (steatosis)
 Liver
cells contain fat deposits; liver is
enlarged

Alcoholic hepatitis
 Liver

inflammation and liver cell failure
Cirrhosis
 Scar
tissue partially blocks sinusoids and bile
canaliculi
ALCOHOLIC LIVER
ALCOHOLIC LIVER
LIVER CANCER
QUESTION
Which of the following is the least virulent strain
of hepatitis?
a. HAV
b. HBV
c. HCV
d. HDV
ANSWER
HAV
Rationale: HBV, HCV, and HDV are all virulent
strains that may lead to chronic viral hepatitis.
HAV is most commonly transmitted by the
fecal-oral route (e.g., contaminated food or
poor hygiene) and does not typically have a
chronic stage (it does not cause permanent
liver damage).
a.
VEINS DRAINING INTO THE HEPATIC
PORTAL SYSTEM
Portal
hypertension
causes pressure
in these veins to
increase
 Varicosities and
shunts develop
 Organs engorge
with blood

PORTAL HYPERTENSION
PORTAL HYPERTENSION
EFFECTS OF PORTAL HYPERTENSION
Hemorrhoids
Ascites &
Caput
medusae
CHOLESTASIS AND INTRAHEPATIC BILIARY
DISORDERS



Bile flow in the liver slows down
Bile accumulates and forms plugs in the ducts
 Ducts rupture and damage liver cells
Alkaline phosphatase released into blood
Liver is unable to continue processing bilirubin
 Increased bile acids in blood and skin
Pruritus (itching)
THE FATE OF BILIRUBIN



Hemoglobin from old
red blood cells
becomes bilirubin
The liver converts
bilirubin into bile
Why would a man with
liver failure develop
jaundice?
unconjugated
bilirubin in
blood
bilirubinemia liver links it
to
gluconuride
jaundice
conjugated
bilirubin
bile
BILIARY TRACT
Gallbladder
Cystic duct
Hepatic
duct
Common bile
duct
Ampulla of Vater
Sphincter of Oddi
Pancreatic
duct
DISORDERS OF THE GALLBLADDER




Cholelithiasis (gallstones)
 Cholesterol, calcium salts, or mixed
Acute and chronic cholecystitis
 Inflammation caused by irritation due to
concentrated bile
Choledocholithiasis
 Stones in the common bile duct
Cholangitis
 Inflammation of the common bile duct
BILE IN THE INTESTINES


Emulsifies fats so they can be digested
Passes on to the large intestine
 Bacteria convert it to urobilinogen
º Some is lost in feces
º Most is reabsorbed into the blood
 Returned to the liver to be reused
 Filtered out by the kidneys  urine
THE PANCREAS
Pancreas
Exocrine
pancreas
Endocrine
pancreas
releases digestive
juices through a
duct
releases hormones
into the blood
to the
duodenum
EXOCRINE PANCREAS

Acini produce:
Inactive digestive
enzymes
 Trypsin inactivator
 Bicarbonate (antacid)

These are sent to the
duodenum when it
releases secretin and
cholecystokinin
 In the duodenum, the
digestive enzymes are
activated

QUESTION
Tell whether the following statement is true or
false.
The exocrine pancreas produces insulin.
ANSWER
False
Rationale: Beta cells of the endocrine pancreas
produce insulin; the exocrine pancreas
produces digestive enzymes that are secreted
into the small intestine through the common
bile duct.
BILIARY REFLUX
1. Gallbladder
contracts
2. Bile is sent
down common
bile duct
3. Blockage forms
in ampulla of Vater:
bile cannot enter
duodenum
5. Bile in
pancreas
disrupts
tissues;
digestive
enzymes
activated
4. Bile
goes up
pancreatic
duct
AUTODIGESTION OF THE PANCREAS

Activated enzymes begin to digest the
pancreas cells
Severe pain results
 Inflammation produces large volumes of serous
exudate  hypovolemia

Enzymes (amylase, lipase) appear in the blood
 Areas of dead cells undergo fat necrosis


Calcium from the blood deposits in them
º
Hypocalcemia
CHRONIC PANCREATITIS AND PANCREATIC
CANCER


Have signs and symptoms similar to acute
pancreatitis
Often have:
 Digestive problems because of inability to deliver
enzymes to the duodenum
 Glucose control problems because of damage to
islets of Langerhans
 Signs of biliary obstruction because of
underlying bile tract disorders or duct
compression by tumors