T3 - Hepatic & Biliary Systems Assessment Flashcards
What is the function of the liver in glucose metabolism?
The liver synthesizes glucose via gluconeogenesis and stores excess glucose as glycogen.
What role does the liver play in synthesizing hormones and vitamins?
The liver synthesizes cholesterol and converts proteins into hormones and vitamins.
How does the liver contribute to energy generation?
The liver metabolizes fats, proteins, and carbohydrates to generate energy.
How does the liver contribute to drug metabolism?
The liver metabolizes drugs via various enzyme pathways, including the CYP-450 system.
What is the role of the liver in blood detoxification?
The liver detoxifies the blood by processing and removing toxins and waste products.
What function does the liver serve in the acute-phase immune response?
The liver is involved in the acute-phase of immune support, producing proteins and factors necessary for the body’s defense mechanisms.
How does the liver contribute to iron metabolism?
The liver processes hemoglobin (HGB) and stores iron.
What is the role of the liver in coagulation?
The liver synthesizes coagulation factors, with the exception of factors III, IV, VIII, and von Willebrand factor (vWF).
How does liver dysfunction impact overall health?
Liver dysfunction can lead to multi-organ failure as nearly every organ is impacted by liver function.
How does the liver aid in volume control?
The liver aids in volume control by serving as a blood reservoir.
How many segments does the liver have?
The liver has 8 segments.
How are the right and left lobes of the liver separated?
The right and left lobes of the liver are separated by the Falciform Ligament.
What branches into each segment of the liver?
The Portal Vein and Hepatic Artery branch into each segment of the liver.
How many hepatic veins empty into the inferior vena cava (IVC)?
Three hepatic veins, namely the Right, Middle, and Left hepatic veins, empty into the inferior vena cava (IVC).
How does bile drainage occur in the liver?
- Bile ducts travel along portal veins, and
- Bile drains through the hepatic duct into the gallbladder (GB) and common bile duct (CBD)
- Bile enters duodenum via ampulla of vater
Through what structure does bile enter the duodenum?
Bile enters the duodenum via the Ampulla of Vater.
The liver receives 25% of cardiac output (COP)
1.25 to 1.5 L/min
Which organ has the highest proportionate COP?
The liver has the highest proportionate COP of all organs.
Where does the portal vein arise from?
The portal vein arises from the splenic vein and superior mesenteric vein.
What is the oxygenation status of blood in the portal vein?
Where does it originate from?
Blood in the portal vein is deoxygenated, originating from the gastrointestinal (GI) organs, pancreas, and spleen.
What percentage of hepatic blood flow (HBF) does the portal vein provide?
The portal vein provides 75% of hepatic blood flow (HBF).
Where does the hepatic artery branch off from?
The hepatic artery branches off from the aorta.
What percentage of hepatic blood flow (HBF) does the hepatic artery provide?
The hepatic artery provides 25% of hepatic blood flow (HBF).
How is oxygen delivered to the liver?
Oxygen delivery to the liver is divided: 50% via the portal vein (deoxygenated) and 50% via the hepatic artery (partially oxygenated).
How is hepatic arterial blood flow related to portal venous blood flow?
Hepatic arterial blood flow is inversely related to portal venous blood flow.
How is hepatic blood flow regulated?
Through what mechanism?
Hepatic blood flow is autoregulated
(The hepatic artery dilates in response to low portal venous flow to maintain consistent hepatic blood flow (HBF).)
Portal venous pressure reflects splanchnic arterial tone and intrahepatic pressure.
- Can lead to blood backing up into the systemic circulation, resulting in complications such as esophageal and gastric varices.
Hepatic Venous Pressure Gradient is used for:
Determining the severity of portal hypertension
Video animation:
https://www.youtube.com/watch?v=LkXQTDb8g2U
What are some common risk factors for liver disease?
Risk factors for liver disease include
- Family history
- Heavy alcohol consumption (ETOH)
- Lifestyle factors
- Diabetes mellitus (DM),
- Obesity,
- Illicit drug use,
- Multiple sexual partners
- Tattoos
- Transfusions.
What are some common symptoms of late-stage liver disease?
Late-stage liver disease may present with vague symptoms such as disrupted sleep and decreased appetite.
What are some common physical exam findings in liver disease?
Common physical exam findings in liver disease include
- Pruritus
- Jaundice
- Ascites
- Asterixis (flapping tremor)
- Hepatomegaly
- Splenomegaly
- Spider nevi.
Hepato-biliary Function Tests:
LABS:
Standard labs:
-BMP
- CBC
- PT/INR
Liver enzymes:
- Aspartate aminotransferase (AST)
- Alanine aminotransferase (ALT) most - liver-specific enzymes
- Bilirubin
- Alkaline Phosphatase
- ɣ-glutamyl-transferase (GGT)
Hepato-biliary Function Imaging:
Imaging
Ultrasound
Doppler U/S (Portal bld flow)
CT
MRI
What are the biomarkers for acute liver failure (ALF)?
In acute liver failure (ALF), AST and ALT levels may be elevated up to 25 times the normal range.
What is the typical AST:ALT ratio in alcoholic liver disease (ALD)?
In alcoholic liver disease (ALD), the AST:ALT ratio is usually at least 2:1.
What is the typical AST:ALT ratio in non-alcoholic fatty liver disease (NAFLD)?
In non-alcoholic fatty liver disease (NAFLD), the AST:ALT ratio is usually 1:1.
What biomarkers indicate reduced synthetic function of the liver?
Reduced synthetic function of the liver is indicated by decreased albumin levels and increased PT/INR.
What biomarkers indicate cholestasis?
Cholestasis is indicated by increased levels of:
- Alkaline phosphatase (Alk Phosphatase)
- Gamma-glutamyl transferase (GGT)
- Bilirubin.
Look at this differential diagnosis of Hepatobiliary Disorders
Flash cards added at the end
What are the functions of hepatocytes in bile secretion?
Hepatocytes secrete bile through bile ducts into the common hepatic duct (CHD), which leads to the gallbladder (GB) and common bile duct (CBD).
How does the gallbladder (GB) function in bile storage?
The gallbladder (GB) stores bile to deliver it during meals, while the common bile duct (CBD) secretes bile directly into the duodenum.
What are the risk factors for cholelithiasis?
Risk factors for cholelithiasis include obesity, high cholesterol levels, diabetes mellitus (DM), pregnancy, being female, and a family history of gallstones.
What percentage of cases of cholelithiasis are asymptomatic?
Approximately 80% of cases of cholelithiasis are asymptomatic.
What are the common symptoms of cholelithiasis?
Common symptoms of cholelithiasis include
- Right upper quadrant (RUQ) pain referred to the shoulders,
- Nausea & vomiting
- Indigestion
- Fever in cases of acute obstruction.
What are the treatment options for cholelithiasis?
Treatment options for cholelithiasis include
- Intravenous fluids (IVF)
- Antibiotics (abx)
- Pain management
- Laparoscopic cholecystectomy (removal of the gallbladder).
Types of Cholecystectomy:
What is choledocolithiasis?
Choledocolithiasis refers to the presence of gallstones (calculi) in the common bile duct (CBD). Biliary colic.
What is the initial presentation of a stone obstructing the common bile duct (CBD)?
Initial symptoms include nausea, vomiting, cramping, and right upper quadrant (RUQ) pain, known as biliary colic.
What are the symptoms of cholangitis?
Symptoms of cholangitis (inflammation of the CBD) include fever, rigors (shaking chills), and jaundice.
What is the preferred treatment for stone removal in cases of CBD
The preferred treatment is endoscopic removal of the stone via endoscopic retrograde cholangiopancreatography (ERCP).
What does ERCP stand for?
ERCP stands for Endoscopic Retrograde Cholangiopancreatography.
Describe the procedure of ERCP.
During ERCP, an endoscopist threads a guidewire through the Sphincter of Oddi into the Ampulla of Vater to retrieve the stone from the pancreatic duct or CBD.
What position is typically used during ERCP, and why?
Patients are usually placed in a prone position with left tilt during ERCP to facilitate the procedure. The endotracheal tube (ETT) may be taped to the left side to prevent displacement.
What medication may be required during ERCP in the event of Oddi Spasm?
Glucagon may be required to manage Oddi Spasm during ERCP.
Common bile duct obstruction picture:
ERCP Procedure picture:
What is bilirubin?
Bilirubin is the end product of heme breakdown.
Describe unconjugated bilirubin.
- Unconjugated bilirubin, also known as “indirect” bilirubin, is bound to albumin in the plasma.
- It is transported to the liver, where it is conjugated into its water-soluble “direct” state before being excreted into bile.
What causes unconjugated (indirect) hyperbilirubinemia?
Unconjugated hyperbilirubinemia occurs due to an imbalance between bilirubin synthesis and conjugation.
What causes conjugated (direct) hyperbilirubinemia?
Conjugated hyperbilirubinemia is caused by an obstruction in the biliary system, leading to the reflux of conjugated bilirubin into the circulation.
What are the five most common types of viral hepatitis?
The five most common types are hepatitis A, B, C, D, and E.
How has the overall prevalence of viral hepatitis changed over time?
Overall, viral hepatitis is on the decline due to vaccines and newer treatments
Which types of viral hepatitis are more chronic?
Hepatitis B and C are more chronic compared to other types.
What is the most common viral hepatitis requiring liver transplant in the United States?
Hepatitis C virus (HCV) (75% type 1) is the most common viral hepatitis requiring liver transplant in the US.
What is the recommended treatment for hepatitis C?
Treatment for hepatitis C depends on factors such as genotype, stage of the disease, and presence of cirrhosis.
A common treatment regimen is a 12-week course of sofosbuvir/velpatasvir, which provides 98-99% clearance of genotype 1A/1B.
HCV Cycle Picture
Acute and Chronic Hepatitis Symptoms image:
Hepatitis A
- Mode of Transmission: Fecal-oral, sewage-contaminated water or shellfish
- Incubation Period: 20–37 days
- Serum Antigen and Antibody Tests: IgM early, IgG appears during convalescence
- Course: Acute, does not progress to chronic liver disease
- Prevention after Exposure: Pooled γ-globulin, hepatitis A vaccine
- Mortality: <0.3–0.6%
Hepatitis B
- Mode of Transmission: Transfusions, percutaneous, sexual, perinatal
- Incubation Period: 60–110 days
- Serum Antigen and Antibody Tests: HBsAg and anti-HBcAg early and persist in carriers
- Course: Chronic liver disease develops in 1–5% of adults and 80–90% of children
- Prevention after Exposure: Hepatitis B immunoglobulin, hepatitis B vaccine
- Mortality: 0.3–1.5%
Hepatitis C
Mode of Transmission: Transfusions, percutaneous, sexual, perinatal
Incubation Period: 35–70 days
Serum Antigen and Antibody Tests: Anti-HCV in 6 weeks to 9 months
Course: Chronic liver disease develops in up to 75%
Prevention after Exposure: Two protease inhibitors +/− interferon
Mortality: Unknown
Hepatitis D
Mode of Transmission: Percutaneous
Incubation Period: 60–110 days
Serum Antigen and Antibody Tests: Anti-HDV late; may be short lived
Course: Coinfection with type B
Prevention after Exposure: Unknown
Mortality: Acute icteric hepatitis: 2–20%
Hepatitis E
Mode of Transmission: Fecal-oral, contaminated water
Incubation Period: 15–60 days
Serum Antigen and Antibody Tests: IgM early, IgG appears shortly afterwards
Course: Usually acute, may cause chronic liver disease in those with weakened immune systems
Prevention after Exposure: Ribavirin in immunocompromised
Mortality: 1%, 10–30% among pregnant women
Alcoholic Liver Disease (ALD) in America
- ALD is increasing in prevalence.
- Most common cause of cirrhosis.
ALD and Liver Transplants
- Leading reason for liver transplants in the U.S.
- 2% of liver transplants nationwide are for ALD.
Reporting of ALD
- Underreporting of ALD is common.
- Stigma contributes to underreporting.
Reporting of ALD
Underreporting of ALD is common due to stigma.
- Initially may show no symptoms.
- Symptoms of liver failure emerge as it progresses.
Treating ALD
Abstinence from alcohol is central to treatment.
Management of ALD Symptoms
Treatment includes managing symptoms of liver failure.
ALD and Platelet Count
Plt count <50,000 requires transfusion
Platelet count below 50,000 may necessitate a blood transfusion.
Liver Transplant for ALD
Patients with ALD may be eligible for a liver transplant if they meet specific criteria.
What symptom of ALD is a result of poor dietary habits and absorption?
Malnutrition
What symptom of ALD is due to malnutrition and altered metabolism?
Muscle wasting
Which gland enlargement is associated with chronic ALD?
Parotid gland hypertrophy
What symptom of ALD results from liver dysfunction and causes yellowing of the skin and eyes?
Jaundice
What term describes a low platelet count often associated with chronic liver disease?
Thrombocytopenia
What is the term for the accumulation of fluid in the abdomen, indicating advanced liver disease?
Ascites
What is the term for the enlargement of the liver and spleen seen in ALD?
Hepatosplenomegaly
What term describes the swelling of the feet and ankles due to fluid retention in ALD?
Pedal edema
When may symptoms of alcohol withdrawal occur after stopping drinking?
24-72 hours after cessation of alcohol intake
Which lab value is typically elevated in ALD and indicates a change in red blood cells?
Mean corpuscular volume (MCV)
Which lab values are typically elevated due to liver damage in ALD?
Liver enzymes
What enzyme, often elevated in ALD, can indicate liver disease and heavy alcohol use?
Gamma-glutamyl transferase (GGT)
What lab value, when elevated, indicates impaired liver function in ALD?
Bilirubin
What lab test measures acute alcohol intoxication?
Blood ethanol level
What is the trend of non-alcoholic fatty liver disease (NAFLD) in the US?
AFLD is on the rise in the United States.
How is non-alcoholic fatty liver disease (NAFLD) diagnosed?
NAFLD is diagnosed when hepatocytes contain more than 5% fat.
What are the primary risk factors associated with non-alcoholic fatty liver disease (NAFLD)?
Obesity, insulin resistance, type 2 diabetes mellitus (DM2), and metabolic syndrome.
What conditions can NAFLD progress to?
NAFLD can progress to non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma.
What has NAFLD and its progression, NASH, become in the context of liver transplants in the US?
NAFLD and NASH have become additional leading causes of liver transplant in the United States.
What methods are used for the diagnosis of NAFLD?
Diagnosis is made through imaging and histology.