largest gland of the body
liver
liver is responsible for
manufacturing, storing, altering and excreting a large number of substances involved in metabolism
the liver is especially important in the regulation of
glucose and protein
what does the liver secrete
bile
the liver is a very vascular organ that receives blood from the ___ ______ via the _____ _____ and from the _____ _____.
GI tract , portal vein, hepatic artery
the blood coming from the GI tract is
rich in nutrients, poor in oxygen
the blood coming from the hepatic artery is
rich in oxygen
liver cells
hepatocytes
what are the Kupffer cells and what do they do
they are phagocytic cells belonging to the reticuloendothelial system and they engulf particulate matter(bacteria) that enters the liver through the portal vein (coming from the GI tract)
what does the sphincter of Oddi do
controls the flow of bile from the gall bladder into the intestine
functions of the liver
glucose metabolism, ammonia conversion, protein metabolism, fat metabolism, vitamin and iron storage, bile formation, bilirubin excretion, drug metabolism
age related changes of the hepatobiliary system
steady decrease in size and weight of the liver, decrease in blood flow, decrease in replacement/repair of liver cells after injury, reduced drug metabolism, slow clearance of hepatitis B surface antigen, more rapid progression of hepatitis C infection an
glucogenolysis
glycogen stored in the hepatocytes is converted to glucose
gluconeogenesis
liver uses amino acids from protein breakdown to synthesize glucose in response to hypoglycemia
the use of amino acids for gluconeogenesis results in the byproduct_____
ammonia
the liver converts ammonia into
urea
what else produces ammonia
bacteria in the gut
the liver uses amino acids for
protein synthesis
fatty acids are broken down by the liver for
energy and ketone bodies
bile salts are synthesized by the hepatocytes from
cholesterol
what causes increased bilirubin in the blood
flow of bile is impeded, liver disease, and excessive destruction of the RBCs
results of liver function tests do not normally change in the elderly
abnormal results in elderly patients indicate abnormal liver function and are not a result of the aging process
metabolism of medications by the liver decreases in the elderly
this necessitate careful medication administration and monitoring, if appropriate, reduced dosages may be needed to prevent medication toxicity
potential risk factors for liver disease
foreign travel, IV or injection drug use, exposure to infectious agents, sexual practices
the liver can be palpated in
the right upper quadrant
the liver presents as
a firm sharp ridge with a smooth surface
the liver of a patient with viral hepatitis is
tender
the liver of a patient with alcoholic hepatitis is
not tender
more than _____ of the parenchyma of the liver may be damaged before liver function test results become abnormal
70%
sensitive indicators of injury to the liver cells and are useful in detecting acute liver disease such as hepatitis
serum aminotransferases-ALT, AST, GGT
most frequently used tests of liver damage
ALT, AST, GGT,
increases in liver disorders
ALT
may be used to monitor the course of hepatitis or cirrhosis
ALT
used to monitor the effects of treatments that may be toxic to the liver
ALT
present in tisssues that have high metabolic activity
AST
may be increased if there is damage to or death of tissues of the organs such as the heart, liver, skeletal muscle and kidney
AST
not specific to liver but may be increased in cirrhosis, hepatitis, and liver cancer
AST
associated with cholestasis and alcoholic liver disease
GGT
done to examine liver cells
needle aspiration
side effects of liver biopsy
bleeding and bile peritonitis
what studies are done before liver biopsy and why
coagulation studies, bleeding risk
Ultrasound, CT, and MRI are used to
identify normal structures and abnormalities of the liver and biliary tree
laparoscopy is
the insertion of a fiberoptic endoscope through a small abdominal inscision
laparoscopy is used to
examine the liver and other pelvic structures and to perform guided liver biopsy, to determine the cause of ascites, and to diagnose and stage tumors of the liver and other abdominal organs
what is important preprocedure of liver biopsy
blood coagulation studies, donor blood available
signed consent
measure pulse, respirations, and BP immediately before procedure
describe to the patient in advance: steps of the procedure, sensations to expect, after-effects anticipated, restrictions of a
what is important post liver biopsy
lie on right side on pillow and remain there without moving for several hours
caution patient against _____ and_____ after biopsy
coughing and straining
take vitals
every 15 min for first hour and every 30 min for the next 1 to 2 hours
avoid strenuous activity and lifting for
1 week
jaundice becomes clinically evident when the serum bilirubin level exceeds
2.5 mg/dL
increased bilirubin and jaundice may be a result of
1. impairment of hepatic uptake
2. conjugation of bilirubin
3. excretion of bilirubin into the biliary system
types of jaundice
hemolytic, hepatocellular, obstructive, hereditary hyperbilirubinemia
result of increased destruction fo RBCs
hemolytic jaundice
free biliruben levels high enough to cause brainstem damage
20-25 mg/dL
inability of damaged liver cells to clear normal amounts of bilirubin from the blood
hepatocellular jaundice
patients with hepatocellular jaundice may be mildly or severely ill with symptoms
anorexia, nausea, malaise, fatigue, weakness, and possible weight loss
what does increased AST and ALT indicate
cellular necrosis
symptoms of infectious disease
fever, headache, chills,
obstructive jaundice
BILE CANNOT FLOW NORMALLY INTO THE INTESTINE AND BECOMES BACKED UP INTO THE LIVER SUBSTANCE-caused by occlusion of the bile duct from a gall stone or an inflammatory process, tumor, or pressure from an enlarged organ. may also be an obstruction from withi
medications that can cause cause stasis and inspissation (thickening) of the bile within the canaliculi
cholestatic agents- phenothiazines, antithyroid medications, sulfonylureas, tricyclic antidepressant agents, nitrofurantoin, androgens and estrgens, propythioruacil, amoxicillin-clavulanic acid, and erythromycin estolate
increased pressure throughout the portalvenous system that results from obstruction of blood flow through the damaged liver
portal hypertension
what is portal hypertension commonly associated with
hepatic cirrhosis
two major consequences of portal hypertension
ascites and varices
cirrhosis is a form of
hepatocellular jaundice
symptoms of obstructive jaundice
deep orange and foamy urine, light or grey colored stool, itching, dyspepsia and intolerance to fatty foods. bilirubin and alkaline phosphatase levels are elevated
presenting symptoms of ascites
increased abdominal girth, weight gain, shortness of breath
other s/s of ascites
striae, distended veins, umbilical hernias, electolyte imbalances
medical management of ascites
dietary management, diuretics, bed rest, paracentesis, transjugular intrahepatic portosystemic shunt, diuretics, bed rest
develop in the majority of patients with cirrhosis
esophageal varices
factors that contribute to hemorrhage
muscular exertion from lifting heavy objects, straining at stool, sneezing, coughing, or vomiting, esophagitis, irritation of vessels by poorly chewed foods or irritating fluids, and reflux of stomach contents (especially alcohol)
clinical manifestations of esophageal varices
hematemesis, melena, general deterioration in mental or physical status and often has a history of alcohol abuse, signs and symptoms of shock
signs and symptoms of shock
cool clammy skin, hypotension, tachycardia, decreased urine output, weak peripheral pulses
what is used to identify bleeding site
endoscopy, barium swallow, ultrasonography, CT, and angiography
pts with cirrhosis should undergo screening for varices how often
every two years
manometer reading in spleen that is normal
20 mL saline
medical management of esophageal varicosities
treatment for shock, IV fluids with electrolytes and volume expanders (be careful not to give too much which would cause hypervolemia and more bleeding),
preferred treatment for esophageal varicosities
nonsurgical because of poor patient health and high mortality rate
pharmacological therapy esophageal varicosities
vasopressin, used only in urgent situations
what does vasopressin do
produces constriction of the splanchnic arterial bed decreasing portal pressure
vasopressin has a diuretic effect
monitor ins and outs and electrolytes
contraindications of vasopressin
coronary artery disease-may precipitate MI
other pharmicological measures to decrease bleeding
(vasopressin), somatostatin, octreotide
benefit to somatostatin and octreotide
doesn't cause coronary artery constriction
used to prevent a first bleeding episode in patient with known varices and to prevent rebleeding
propranolol (Inderal) and nadolol (Corgard) -used only prophylactically