Biliary System
refers to the organs and ducts that contribute to the production and transport of bile into the duodenum to aid in digestion
Biliary organs
GALLBLADDER, liver, pancreas
Ductal systems associated with the biliary system
hepatic ducts, cystic duct, common bile duct, pancreatic duct
Liver location
upper-right quadrant of the torso, immediately below the diaphragm, and is on top of the stomach, right kidney and intestines
Liver
largest organ in the body, weighs 3-4lbs
Glisson's capsule
tough fibrous tissue that completely covers the liver. contains blood vessels and lymphatics. also contains pain receptors
Portal vein
large vein that brings blood to the liver
Blood flow (Portal Circulation)
esophagus, stomach, spleen, intestines --> portal vein --> liver --> hepatic portal vein --> inferior vena cava --> right side of heart
Hepatic artery
oxygenated blood flows directly from the heart to the liver
At any given moment the liver holds about ___ of the body's total blood volume
1/3
The ___ lobe of the liver is ___ times larger than the ___
right; 6; left
Lobules
hexagonally-shaped functional units of the liver arranged in layers that radiate from the central vein; lobules are connected to small ducts that connect to larger ducts that ultimately form the hepatic duct
Portal triad
distinctive arrangement in the liver; a component of lobules; each segment has: a vein, an artery and cystic duct
Path of bile and wastes from liver
flow into a vast network of intrahepatic cuts that become larger in size and eventually form the right and left hepatic ducts which merge into the common hepatic duct
Common Bile Duct empties
bile into the duodenum
Liver's primary functions
bile formation, metabolism, vitamin storage, manufacturing anticoagulant and coagulant substances and detoxification
Liver can lose ___ of its cells before it stops functioning
3/4
only organ in the body that can regenerate itself
Common symptoms of liver disease:
jaundice, cholesthasis, hepatomegaly, portal hypertension, ascites, liver encephalopathy
jaundice
a yellow discoloration of the skin and eye whites due to abnormal high levels of bilirubin (brownish/yellow substance found in bile)
cholesthasis
reduced or stopped bile flow; can be caused by hepatitis, stone in bile duct, bile duct cancer, pancreatic cancer
hepatomegaly
liver englargement
portal hypertension
abnormal high pressure in the portal vein that may be due to increased resistance of blood flow through the liver
ascites
fluid build up in the abdominal cavity caused by fluid leaks from the intestine - often associated with portal hypertension
liver encephalopathy
deterioration of brain function due to accumulation of toxic substances that are normally removed by the liver
acute liver disease
occurs when the causation coincides with the symptoms; ex: Hepatitis A - caused by contaminated food and the patient feels violently ill almost immediately - one treated, 6 months until disease free
chronic liver disease
marked by the gradual destruction of the hepatocytes over a period of time; damaged tissue cannot carry out the normal liver functions, the production of proteins and substances is inhibited; also, the blood flow and purification process is altered; death
primary schlerosing cholangitis (PSC)
rare disease in which the bile ducts - both inside and outside the liver- become inflamed resulting in scarring and hardening (fibrosis) that narrows the bile ducts; in most cases PSC leads to cirrhosis, portal hypertension and liver failure; unknown caus
Cholaniocarcinoma may develop in __ - __% of PSC patients
7-15%
Cirrhosis
scarring of the liver; chronic liver disease; C: excessive alcohol consumption, hepatitis, use of certain drugs, chemical exposure, autoimmune disease, diabetes, malnutrition, wilson's disease (too much copper), hemochromatosis (too much iron)
Hepatitis
inflammation of the liver, usually caused by exposure to an infection agent; can be acute or chronic (chronic if disease lasts more than 6 months)
5 Types of Hepatitis Viruses
Hep A, Hep B, Hep C, Hep D, Hep E
Hepatitis A (HAV)
spread primarily through food or water contaminated by stool from an infected person; causes swelling of the liver, but it rarely causes lasting damage; S: feel as if have the flu or no symptoms at all; usually gets better on its own after several weeks
Hepatitis B (HBV)
spreads by contact w an infected person's blood, semen or other bodily fluid. (also woman to baby at birth); S: feel as if have the flu or no symptoms at all; Blood test confirms virus; usually gets better on its own- if not, called chronic HBV, which las
Chronic HBV
Lasts a lifetime; can lead to scarring of the liver, liver failure, or liver cancer
Hepatitis C (HCV)
spread through contact w infected blood; also through sex w infected person or mother to baby; most people do not have symptoms for years; infection can last a lifetime and may lead to liver cancer; medicines sometimes help; serious cases may need a liver
Health experts estimate ___ million people worldwide have chronic Hep C; ___ million in the US
180 million; 4 million in US
Hepatitis C Virus causes chronic infection in more than ___ percent of infected people
85%
Hepatitis D
usually occurs in conjunction w Hep B infection
Hepatitis E
similar to A, prevalent in developing countries
Primary liver cancer symptoms
Pain or discomfort in the right upper abdomen, jaundice, weight loss, distention of the abdomen; MIGHT BE NO symptoms at all in the early stage
Most common type of primary liver cancer
Hepatocellular carcinoma (HCC)
Hepatocellular carcinoma (HCC)
most common type of primary liver cancer; accounts for 80-90% of liver cancers; occurs more in men than women, usually in people 50-60 years old; C: usually cirrhosis
How is diagnosis of primary liver cancer usually made?
blood test, ultrasound, CAT scan, MRI scan;
may also include a biopsy of the tumor itself
Only ___-___% of HCC can be removed completely using surgery
10-20%; chemotherapy and radiation are usually not effective but may be used to shrink large tumors so that surgery has a greater chance of success
If the HCC cannot be completely removed, the disease is usually deadly in ___ to ___ months
3-6 months
Cancer affecting the liver is more commonly ____
metastatic cancer from the colon, lung, breast
Cholaniocarcinomas
account for 1 or 2 out of every 10 cases of liver cancer; these cancers start in the bile ducts
Of those diagnosed with colorectal cancer ___% will have metastatic lesions to the liver, however only ___% will be candidates for synchronous resection
25%, 10%
Ocular Melanoma
rare cancer of melanocytes (cells that produce the pigment melanin) found in the eye; most common site of metastasis is the liver
Pancreas location
lies behind the stomach and is approximately 15-20cm long and 5 cm wide
Ampulla of Vater
formed at the union of the pancreatic duct and the common bile duct; specifically is located at the duodenal pill of Vater/sphincter of Oddi
Sphincter of Oddi
a complex set of muscles that regulate the flow of bile and pancreatic juices into the duodenum, prevent bile from entering the pancreatic duct and prevent intestinal contents from entering the biliary system; if gallbladder is removed the sphincter of Od
Major functions of the pancreas
produce digestive enzymes to aid in digestion of fats and proteins, control the amount of sugar in the blood by producing insulin and other hormones; Endocrine and exocrine glands
Exocrine glands
make up the majority of the pancreas, produce digestive enzymes to aid in digestion of fats and proteins; these enzymes (500-1000ml/day) flow through the pancreatic duct to join the common bile duct to drain through the ampulla into the duodenum
In ___% of people the pancreatic duct joins the common bile duct to drain through the ampulla
93%
Pancreatic divisum
In 7% of the population the common bile duct and the pancreatic duct do not join together and instead enter the ampulla separately
Endocrine glands
Found in the pancreas; control the amount of sugar in the blood by producing insulin and other hormones; these products are released directly into the circulation
Pancreatitis
inflammation of the pancreas (acute and chronic)
Acute Pancreatitis
occurs suddenly/lasts for a short period of time ~3-4 days; usually caused by gallstones or by drinking too much alcohol over time; S: pain in the abdomen, nausea, vomiting, fever, rapid pulse
Approximately ________ cases of acute pancreatitis occur in the US each year and about ___% of the cases lead to severe damage of the pancreas
80,000 ; 20%
Complications that may result from acute pancreatitis:
pancreatic necrosis (parts of the pancreas become dead), pancreatic abscess, pseudocysts (accumulations of fluid and tissue debris around the pancreas), pancreatic fistula, enzymes and toxins enter the bloodstream injuring the heart, lungs and kidneys
Chronic pancreatitis
occurs when digestive enzymes attack and destroy the pancreas and nearby tissues, causing scarring and pain; does not resolve fully and results in slow destruction of the pancreas; C: usually many years of alcohol abuse, but may be triggered by only one a
Complications that may result from chronic pancreatitis
diabetes mellitus, poor absorption of nutrients from the digestive tract (especially fats), cancer of the pancreas, blockage of bile ducts, pseudocyst
Gallstone pancreatitis
an inflammation of the pancreas caused by the obstruction of the ampulla of Vater or a biliary stone
Pancreatic cancer/ Adenocarcinoma of the pancreas
4th leading cause of cancer deaths in men/women in the US; C: unknown, S: loss of appetite, weight loss, abdominal discomfort, nausea and jaundice; Surgical resection is usually the best chance for cure; studies indicate that stents may be an effective pa
Risk factors for developing pancreatic cancer
Obesity, smoking, hereditary history, increase in age, diabetes and chemical exposure
Only ___ to ___% of pancreatic cancer patients are considered surgical candidates
15-20%
Intraductal papillary-mucinous tumors (IPMT)/ Intraductal pancreatic-mucinous tumors (IPMT)
develops in the cell lining of the main pancreatic duct; these tumors secrete a large amount of mucous and cause the pancreatic duct to dilate and obstruct the flow of pancreatic juices to the duodenum. IPMT may give the appearance of cysts; S: abdominal
Gallbladder
non-essential organ; approximately 7-10cm in length and 2.5-3.5 in width; capable of holding up to 50 ml of bile
Bile
a greenish-yellowish fluid comprised of mainly water (97%), bile salts and fatty acids when originally produced by the liver
The bile stored in the gallbladder is concentrated to about ___ of its original volume
1/5
As the bile is secreted from the gallbladder, it flows through the ___
cystic duct
The cystic duct joins with the _____ to form the ____
common hepatic duct, common bile duct
Common bile duct
begins at the bifurcation (division into two branches) of the cystic duct and the common hepatic duct; extends downward until it joins with the main pancreatic duct to form the ampulla of Vater
From the common hepatic duct bile can flow (2 places)
1. to the common bile duct which empties into the duodenum
2. to the cystic duct where it then flows upward in a retrograde path into the gallbladder
Primary function of the gallbladder
store and regulate the amount of bile released into the duodenum
Primary functions of bile
aid in the digestion of fats, help neutralize gastric acids in the duodenum
How much bile is produced by the liver daily
1/2 to one full liter
Cholelithiasis
presence or formation of gallstones in the gallbladder; accounts for 90% of biliary system disease; ~1 million new cases each year and half of those undergo biliary surgery; has been linked to gallbladder cancer
2 types of gallstones
cholesterol stones and pigment stones
cholesterol stones
make up over 50% of all gallstones; form when bile secreted by the liver is supersaturated with cholesterol
risk factors for the formation of gallstones
increase in age, ethnic and hereditary factors, obesity, diabetes, liver cirrhosis, long-term IV nutrition and spinal cord injury
Biliary colic
right upper abdominal pain that feels like cramping
Symptoms of cholelithiasis (typically present after a stone larger than 8mm moves through or becomes lodged in the biliary ducts causing obstruction)
biliary colic, acute cholecystitis
Potential complications of cholelithiasis
cholangitis, perforation of the gallbladder, gangrene and hepatic damage
Choledocholithiasis
presence or formation of stones in the common bile or hepatic ducts
Stones that form in the common bile duct are always ___ stones
Pigment
Cholangitis
inflammation of the bile duct due to bacterial infection; usually caused when the duct is obstructed by a gallstone, stricture or tumor; treatment includes antibiotic therapy and ERCP to drain the obstructed bile ducts; placement of a biliary stent within
Potential complications of choledocholithiasis
biliary colic, obstructive jaundice and acute gallstone pancreatitis
cholecystitis
an acute or chronic inflammation of the gallbladder, usually caused by an obstruction of the biliary ducts by gallstones; occurs more often in women than men and incidence increases after the age of 40; S: abdominal pain in upper right side, nausea, vomit
chronic cholecystitis
caused by repeated mild attacks of acute cholecystitis; may eventually lead to the thickening of the walls of the gallbladder=gallbladder shrinks and eventually loses its ability to properly function
Extrahepatic bile duct cancer
rare adenocarcinoma found in the extra hepatic bile duct. Associated with long-standing ulcerative colitis, Crohn's disease and primary sclerosing cholangitis; S: painless obstructive jaundice; 30% have gallstones
Cholangiocarcinoma
adenocarcinoma of the bile ducts; can occur anywhere within bile ducts, however most common in the hepatic ducts or the ampulla; S: loss of appetite, weight loss, abdominal discomfort, nausea and jaundice; surgical resection is best chance for cure
How is cholangiocarcinoma most often diagnosed
during a laparotomy for another biliary system disease or during a diagnostic procedure to determine the level and cause of a biliary obstruction; at time of diagnosis most tumors have locally spread or metastasized
Risk factors of cholangiocarcinoma
hereditary, age and pre-existing congenital abnormalities of the bile duct
Klatskin's tumor
a cholangiocarcinoma of the common hepatic duct bifurcation (split into two branches); tumor may involve one or both right/left hepatic ducts; generally small tumors, sharply localized and seldom metastasizing; S: jaundice and/or abnormal liver tests
Gallbladder cancer
adenocarcinoma found in the gallbladder; relatively rare and occurs in women more than men; S: very delayed and once appear resemble those of other gallbladder diseases, liver cancer or pancreatic cancer; ~80% of patients with gallbladder cancer have gall
Risk factors for Gallbladder cancer
primary sclerosing cholangitis, ulcerative colitis and cirrhosis, previously having gallstones or polyps in the gallbladder
5 year survival rate for gallbladder cancer
5% (typically by time of diagnosis patients have less than a year)
Ampullary cancer
adenocarcinoma that develops in the ampulla; obstructs flow of bile and causes jaundice => earlier detection than pancreatic cancers