Liver Function Flashcards
Describe the liver
Often called the train station
* Consists of a right and left lobe
* Lobules – functional unit and consist of hepatocytes (liver cells)
* Blood moves through the liver via sinusoids
* Small ducts converge to form R and L hepatic duct
* Hepatic ducts exit liver via common hepatic duct
Roles of the liver
- metabolism
- digestion
- hormonal
- detoxification
Functions of the liver
Dont know if this needs to be known??
Metabolic role of the liver
- CHO
- protein
- lipid
- vitamin storage
- mineral storage
Role of the liver with CHO metabolism
- gluconeogenesis
- glycogen synthesis and breakdown
Role of the liver with protein metabolism
- synthesis of serum proteins
- synthesis of blood clotting factors
- deamination/transamination to produce non-essential aa
- remove and detoxify ammonia through urea synthesis
Role of the liver with lipid metabolism
- synthesis of cholesterol, phospholipids, TG’s
- breakdown of fatty acids for energy production
What vitamins are stored in the liver?
- B vitamins
- Fat soluble vitamins
What minerals are stored in the liver?
- Fe
- Cu
- Mg
- Zn
Role of the liver in digestion
- Production of bile: fat and fat soluble vitamin absorption
- conjugation and excretion of bilirubin (breakdown product of RBCs) to prevent jaundice due to build up
What is given to infants with bile atresion?
MCFAs because they dont need as much bile to absorb it
Hormonal and deotoxification role of liver
- Conjugation and excretion of: aldosterone & alcohol dehydrogenase hormone
- Enzymes in the liver detoxify: alcohol, drugs, poisons
Signs and Symptoms of Liver Disease
- Mild abdominal pain and generalized fatigue are the most common sign (improper storage of glycogen).
- Anorexia
- Muscle wasting (sarcopenia)
- Wt loss
- Jaundice: potential for malabsorption in these conditions (typically end stage)
- Hypoglycemia or hyperglycemia
- Anemia (moderate to severe)
- portal hypertension
- Esophageal varices
- Ascites
- Hypoalbuminemia
- Encephalopathy
AST and ALT in liver disease
Elevation of AST and ALT is not reflective of liver damage
* ALT can be elevated due to muscle physiology
What are esophageal varices
a swollen artery, vein or lymph vessel in the esophagus that can burst open and bleed creating a holeinto other tissue
What is encephalopathy?
Inability to synthesis blood urea nitrogen and can die if ammonia gets high enough
Liver function tests
- ALT (Alanine aminotransferase/transaminase) (very sensitive to hepatic damage)
- AST (aspartate transaminase/aminotransferase) or SGOT (serum glutamic-oxaloacetic transaminase)
- ALP (serum alkaline posphatase)
- Ammonia
- Albumin-may not be a good marker of visceral protein status in liver disease
- Bilirubin
- BUN
- Prothrombin time (PTT)
ALT tests normal vs. liver disease
- Normal Male: 10-40 U/L
- normal Female: 7- 35U/L
- liver disease: ↑↑
AST test normal vs. liver disease
- normal: 10-30 U/L
- liver disease: ↑
ALP test normal vs. liver disease
- normal: 10-30 UL
- liver disease: ↑
Ammonia test normal vs. liver disease
- normal: 15-45 ug N/dL
- liver disease: ↓
albumin test normal vs. liver disease
- normal: 35-48 g/L
- liver disease: ↓
Bilirubin test normal vs. liver disease
- normal: 0.3-1.2 mg/dL
- liver disease: ↑
BUN test normal vs. liver disease
- normal: 6-20 mg/dL
- liver disease: ↓ or normal
PTT test normal vs. liver disease
- noraml 10-13 sec
- liver disease: prolonged