4. Liver Injury Flashcards
What is the location of the liver?
right upper quadrant
The liver receives __% of cardiac output.
25
What are the major blood vessels of the liver?
portal vein
hepatic artery
What are the 3 main functions of the liver?
- energy metabolism
- protein production
- detoxification
What hepatic processes serve as energy metabolism?
- gluconeogeneisis/ glycogenolysis
- cholesterol synthesis
What proteins are produced in the liver?
- albumin
- coagulation factors
What processes are used for detoxification by the liver?
- drug metabolism (phase I and II)
- ammonia, urea cycle
- synthesis of glutathione
What is the Phase I reaction?
- oxidation
What is the Phase II reaction?
covalent attachment of the drug to a water-soluble carrier molecule
Acute liver failure occurs within ____ to _____.
days
weeks
What are some lab values that indicate acute liver failure?
- elevated liver enzymes
- high bilirubin
- high INR (thin blood)
What is the diagnostic triad for acute liver failure?
- < 26 weeks
- INR greater than or equal to 1.5
- encephalopathy
What are the signs and symptoms of chronic liver failure?
- normal or slightly elevated AST, ALT
- minimal/ no symptoms until jaundice
Chronic liver failure is sometimes reversible. (T/F)
True
What is centrolobular necrosis?
direct or metabolite related hepatotoxicity
In centrolobular necrosis, damage spreads from _____ lobe and in an _______ direction.
middle
outward
What is a very common cause of centrolobular necrosis?
acetaminophen overdose
What is steatohepatitis?
an accumulation of fatty acids in hepatocytes
What is a common cause of steatohepatitis?
alcohol
What are the 2 subcategories of steatohepatitis?
- Alcoholic fatty liver diseae
- Non-alcoholic steatohepatitis (NASH)
What are some causes of NASH?
- obesity
- drug induced (tetracycline, valproic acid)
What is the cause of generalized hepatocellular necrosis?
autoimmune
Generalized hepatocellular necrosis has a similar process to viral hepatitis. (T/F)
True
What is cholestatic injury?
slowed bile flow through bile ducts
What are some lab values that indicate cholestatic injury?
high bilirubin and high alkaline phosphate are seen first, followed by increased liver enzymes
What are some main assessments that you must make about the patient in order to appropriately treat condition?
- medication/medical history
- time frame
- occupation
- nutritional status
Diagnosis of liver injury is a diagnosis of _______.
exclusion
What are risk factors for liver injury?
- female
- alcohol use
- malnutrition
- genetic
What could happen to a patient with inadequately treated liver injury?
- chronic liver disease
- fulminant hepatic failure
- death
What is the main treatment plan for liver injury?
- remove offending agent
- antidote
- dialysis
- supportive care
- liver transplant
What is a toxic acetaminophen dose for an adult?
7.5 - 10 g
What is a toxic acetaminophen dose for a child?
150 - 200 mg/kg
Acetaminophen is mainly metabolized via _________.
glucuronidation
A person overdoses on acetaminophen when ______ is depleted.
glutathione
The Rumack-Matthew nomogram can be used __ hours after ingestion.
4
The Rumack-Matthew nomogram is only used for long-term chronic exposure to acetaminophen. (T/F)
False: only for acute exposure
When is activated charcoal an appropriate treatment option for acetaminophen overdose?
within 4 hours of ingestion
When is activated charcoal NOT an appropriate treatment option for acetaminophen overdose?
- N/V prior to administration of charcoal
- lack of airway protection/ or altered mental status
What is the antidote to acetaminophen overdose?
N-acetylcysteine
N-acetylcystein is nearly 100% hepatoprotective if given ≥__ hours after ingestion.
8
What is the oral formulation of N-acetylcystein?
Mucomyst
What is the IV formulation of N-acetylcystein?
Acetadote
What is the loading dose for Mucomyst?
140 mg/kg
What is the maintenance dose for Mucomyst?
70 mg/kg q4h x 17 doses
What is the loading dose of Acetadote?
150 mg/kg
What is the 2nd dose of Acetadote?
50 mg/kg
What is the 3rd dose of Acetadote?
100 mg/kg
