LIVER Flashcards
What is the primary function of the liver?
Regulation of blood glucose levels
Which vitamin is required for the production of clotting factors in the liver?
Vitamin K is essential for the liver’s synthesis of various clotting factors. A deficiency can lead to prolonged bleeding times. These clotting factors are crucial for blood coagulation.
What are the early manifestations of liver cirrhosis?
Fatigue, anorexia, and pruritus
What are the late manifestations of liver cirrhosis?
Jaundice, ascites, and esophageal varices
How does the liver contribute to fat metabolism?
The liver contributes to fat metabolism by:
-Breaking down fatty acids for energy
-Producing ketone bodies during starvation or diabetes
-Converting lipids for energy use
-Storing excess fats and regulating lipid levels in the body
What is a key role of the liver in managing bilirubin levels?
Converts unconjugated bilirubin into conjugated form
Explain the significance of bile formation and its components.
Bile formation is significant because it:
Aids in fat digestion through emulsification
Excretes bilirubin, a waste product
Contains bile salts for recycling in the enterohepatic circulation
Composed of water, electrolytes, bile salts, cholesterol, and bilirubin
What are the clinical signs that may indicate liver dysfunction?
Clinical signs of liver dysfunction may include:
Jaundice (yellowing of skin/eyes)
Pruritus (itching)
Abdominal pain and swelling
Nausea and vomiting
Easy bruising or bleeding
Changes in mental status
Weight gain or loss
Altered bowel habits (diarrhea or constipation)
Describe the role of the liver in glucose metabolism
The liver plays a key role in glucose metabolism by:
Regulating blood glucose levels
Glycogenesis: converting glucose to glycogen for storage
Glycogenolysis: breaking down glycogen to release glucose
Gluconeogenesis: synthesizing glucose from amino acids and lactate
THE LIVER
- The term “liver” is derived from the Old English word “life,” highlighting its critical importance to survival.
- The liver is essential for life, and survival without it is typically impossible beyond a few hours.
- It is the largest intra-abdominal solid organ, weighing approximately 1,500 grams, with a delicate parenchyma, thin capsule, and a fixed position relative to the spine.
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Anatomy and of the Liver
o Positioned below the diaphragm in the right upper quadrant (RUQ) of the abdomen.
o Extends toward the mid-distance between the parasternal and mid-clavicular lines on the left side.
o Palpable just below the right costal margin in some individuals.
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Functions of the Liver
- Glucose Metabolism:
o Regulates blood glucose levels through:
Glycogenesis: Converts glucose into glycogen for storage.
Glycogenolysis: Breaks down glycogen to release glucose.
Gluconeogenesis: Synthesizes glucose from amino acids and lactate.
- Protein Metabolism:
o Synthesizes plasma
proteins (e.g., albumin, clotting factors).
o Requires vitamin K for clotting factor production.
o Uses amino acids as building blocks for proteins.
- Fat Metabolism:
o Breaks down fatty acids for energy and ketone body production.
o Converts lipids during conditions like starvation or uncontrolled diabetes.
o Lipid accumulation in hepatocytes can lead to fatty liver.
- Ammonia Conversion:
o Converts toxic ammonia into urea for excretion via urine.
o Removes ammonia from portal blood and metabolic processes.
- Vitamin and Iron Storage:
o Stores vitamins (A, B, D) and minerals like iron and copper.
o Acts as a reservoir for essential nutrients.
- Drug and Hormone Metabolism:
o Metabolizes medications, reducing or activating their effects.
o Processes hormones like estrogen, testosterone, and aldosterone to prevent their accumulation.
- Bile Formation:
o Produces bile, which contains water, electrolytes, bile salts, cholesterol, and bilirubin.
o Functions:
Excretes bilirubin.
Aids in fat digestion via emulsification.
Facilitates enterohepatic circulation, recycling bile salts.
- Bilirubin Excretion:
o Converts unconjugated bilirubin into conjugated form for bile secretion.
o Processes bilirubin through enterohepatic circulation and excretes it via feces and urine.
- Immunity:
o Synthesizes antibodies and immune components to resist infection
Assessment: Health History
- Exposure History:
o Hepatotoxic substances (e.g., chemicals, medications).
o Infectious agents (e.g., hepatitis viruses).
o Occupational, recreational, and travel exposures to hepatotoxins.
- Substance Use and Lifestyle:
o Alcohol and drug use (e.g., injectable drugs).
o Sexual practices that may increase hepatitis risk.
- Medical and Surgical History:
o Current and past medical conditions.
o History of blood transfusions.
Assessment: Nursing History
- General Symptoms:
o Malaise, fatigue, sleep disturbances, fever. - Gastrointestinal Symptoms:
o Indigestion (dyspepsia), heartburn (pyrosis), nausea, vomiting.
o Abdominal pain, anorexie, alteration in bowel patterns.
- Systemic Signs:
o Jaundice, pruritus (itching).
o Weight gain, edema, ascites
- Serious Manifestations:
o Hematemesis (vomiting blood), melena (black tarry stools), hematochezia (blood in stool).
o Easy bruising, changes in mental acuity, personality changes.
Physical Examination Findings
- Skin and Nails:
o Corneal Arcus: White or gray ring around the cornea (lipid deposits).
o Leukonychia: White spots on nails.
o Terry’s Nails: White nail beds with dark tips (associated with liver disease).
Diagnostic Evaluation for Liver Disease:
- Liver Function Tests (LFTs):
o Protein Studies:
Total Serum Protein: Normal 7.0-7.5 g/dL.
Serum Albumin: Normal 3.5-5.5 g/dL.
Abnormalities indicate cirrhosis, chronic hepatitis, or fluid imbalances (e.g., ascites).
o Prothrombin Time (PT):
Normal: 11-13.5 seconds.
Prolonged PT that does not normalize with vitamin K suggests severe liver damage.
o Enzymes:
AST (SGOT): 10-40 U/L.
ALT (SGPT): 5-35 U/L (primary marker for liver cell damage).
LDH: 165-400 U/L.
o Blood Ammonia:
Normal: 20-120 μg/dL. Elevated levels indicate liver failure.
o Cholesterol:
Normal: 150-250 mg/dL. Elevated in biliary obstruction; decreased in liver cell damage. - Imaging and Procedures:
o Liver biopsy (gold standard for liver pathology).
o CT, MRI, and radioisotope scans.
o Laparoscopy for direct visualization of liver abnormalities.
Liver Cirrhosis: Overview
* Definition: A chronic, degenerative, and inflammatory condition in which normal liver tissue is replaced with scar tissue, leading to impaired liver function.
* Progression: Develops slowly over months or years. Early stages are often asymptomatic, but symptoms and complications emerge as the disease progresses.
Causes of Liver Cirrhosis:
- Alcohol-related: Chronic alcoholism.
- Metabolic Disorders:
o Non-alcoholic fatty liver disease (NAFLD).
o Hemochromatosis (iron overload).
o Wilson’s disease (copper accumulation).
o Alpha-1 antitrypsin deficiency. - Infectious: Chronic hepatitis B and C.
- Other Causes:
o Cryptogenic (unknown causes).
o Drug toxicity.
o Gallbladder obstruction.
o Vascular conditions (e.g., heart failure).
Pathophysiology
- Fibrosis Formation: Chronic injury leads to inflammation and deposition of fibrous and fatty tissue, replacing healthy liver cells.
- Portal Hypertension: Fibrosis disrupts normal blood flow through the liver, increasing pressure in the portal venous system.
- Hepatocellular Failure: Impaired hepatocyte function leads to detoxification deficits and metabolic dysfunction.
Clinical Manifestations
Early Manifestations:
- Fatigue, anorexia, chronic dyspepsia, flatulence.
- Abdominal pain, liver tenderness.
- Change in bowel habits (constipation or diarrhea).
- Pruritus (itching).
- Weight changes and evening ankle edema.
- Minor bleeding (e.g., epistaxis, bleeding gums).
Late Manifestations:
- Portal Hypertension:
o Esophageal and gastric varices (bleeding risk).
o Splenomegaly and ascites.
o Caput medusae (dilated abdominal veins). - Hepatocellular Failure:
o Jaundice/Icterus: Yellow discoloration of skin and mucous membranes due to elevated bilirubin levels
Skin Manifestations:
- Palmar erythema: Redness of the palms.
- Spider angiomas (spider nevi): Dilated blood vessels radiating from a central point.
- Caput medusae: Enlarged veins on the abdomen resembling a palm tree.
Endocrine Disturbances:
- Aldosterone: Fluid retention and high blood pressure.
- Estrogen and Testosterone:
o Gynecomastia in men.
o Loss of pubic and axillary hair.
o Pectoral alopecia.
Hematologic Disorders:
- Bleeding Tendencies:
o Due to decreased synthesis of clotting factors (e.g., fibrinogen, prothrombin).
o Signs include petechiae, purpura, ecchymoses, and gum bleeding. - Hypersplenism: Causes anemia, leukopenia, and thrombocytopenia.
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Liver Cirrhosis: Comprehensive Summary
Peripheral Neuropathy in Cirrhosis
- Definition: Damage to peripheral nerves leading to impaired sensation, movement, and organ function.
- Causes: Dietary deficiencies, including thiamine, folic acid, and vitamin B12, often due to malnutrition.
