370.3: Hepatic Disorders Flashcards
What are the 2 sources of blood to the liver?
- Hepatic artery (500mL/min)
- Hepatic Portal Vein (1000mL/min)
= partially oxygenated
= connects back with inferior vena cava after filtering blood
What are the functions of the liver?
- Blood filtration + detox
- RBC production in fetus
- Synthesis + storage of amino acids, glycogen, blood proteins (albumin, fibrinogen, globulin, Heparin, clotting factors), vitamins (A, B, D, E, K), minerals, and fats
- Formation/excretion of bile
- Blood glucose regulation
- Hormone synthesis (ex. Angiotensin)
What is the pathophysiology pathway of injury on the liver?
- Injury (virus, obesity, alcohol, drugs)
- Hepatitis
- A. Inflammation
- B. Apoptosis
- C. Fibrosis. ⤴️ back to inflammation
- Cirrhosis (fibrosis + scar tissue)
- Hepatocellular Carcinoma
- Liver failure
What are EARLY clinical manifestations of liver dysfunction?
Early:
- Fatigue
- Weight changes
- GI disturbances
- Dull pain in RUQ/epigastrium
- FEVER
- Malaise
- Enlarged liver + spleen
- Pruritus
What are LATE clinical manifestations of liver dysfunction?
Late:
- Jaundice
- Skin lesions (spider angiomas, palmar erythema)
- Hematologic problema
- Endocrine disturbances
- Peripheral neuropathy
Why do skin lesions, such as spider angiomas and palmar erythema, present in liver dysfunction?
Theory caused by high levels of estrogen:
- Produces arterial vasodilation
- Liver detoxifies estrogen from blood
- Can be toxic
What are manifestations of Liver Disease?
- Portal hypertension
- Ascities
- Hepatic-encephalopathy
- Jaundice
- Hepatorenal Syndrome
What are the presentations of Portal Hypertension?
- Portal hypertension = 10 mmHg or greater (normal = 3 mmHg)
- Swelling, inflammation, fibrosis, scarring of liver
- Thrombosis
- Resistance in inferior vena cave = R CHF, myopathy
- Blood takes collateral channels = esophagus, anterior abdominal wall, rectum
What are consequences of portal hypertension?
- Varices (inc intersplenic pressure, 1/3 platelets stored can inc)
- Splenomegaly
- Ascites
- Hepatic encephalopathy (d/t toxic ammonia buildup)
Esophageal varices
- Collateral circulation develops in lower esophagus
- Most common symptom of portal hypertension is vomiting blood from bleeding esophageal varices
- Portal pressure >10% takes 4 years to develop varices
- More likely to rupture at Bottun, more reflux and acidity
What are symptoms of hepatic encephalopathy?
- Impaired cognition
- Asterixis (flapping hands)
- EEG changes
- Personality changes
- Confusion, memory loss
- Stupor, coma, death
What is the pathophysiology of hepatic encephalopathy?
Poor liver function permits neurotoxins and other harmful substances absorbe from GI tract to circulate to brain
(ex. AMMONIA)
What levels of bilirubin cause Jaundice?
Bilirubin > 2.5 - 3 mg/dL
What are the 3 types of Jaundice?
- Hemolytic
- Obstructive
- Hepatocellular
Hemolytic Jaundice
Excessive destruction of RBCs
- Mismatched blood transfusion
- Sickle Cell Disease
- Fetal/maternal mismatch
- Hemolytic anemia
- Severe infection
- Toxins
- Immune response
Obstructive Jaundice
Blockage in the passage of conjugated bilirubin (water soluble) from the liver to the intestine.
- Gallstone/tumour obstruction of bile duct
- Obstruction of bile flow through liver
Hepatocellular Jaundice
Failure of liver cells to conjugate bilirubin and of bilirubin to pass from liver to intestine.
- Hepatitis
- Biliary cirrhosis
- Physiological changes
- Baby Jaundice
How are where does bilirubin get conjugated?
- Bilirubin passes from blood cells to liver
- Albumin needed to transfer
- Liver conjugates bilirubin into water-soluble molecule
- Passes through bile duct into intestines
- Urobilinogen formed by bacteria in gut
- Excreted as STERCOBILIN in feces
OR - Reabsorbed by kidneys and excreted as UROBILIN in urine
Where is one place a nurse can see Jaundice on every patient?
Sclera of eyes
What is the hematological mechanism of Jaundice?
- Excessive lysis of RBCs
- Hepatocytes Connor conjugate + excrete bilirubin as rapidly as formed
- Bilirubin enters bloodstream
- UNCONJUGATED HYPERBILIRUBINEMIA
- Jaundice (bilirubin deposits in tissues)