Major Vascular I Flashcards
What percent of cardiac output goes to the liver?
25%
What vessels supply blood to the liver?
- Hepatic artery
- Portal vein
What percent of the blood supply to the liver comes from the hepatic artery?
25-30%
What percent of the blood supply to the liver comes from the portal vein?
70-75%
The metabolizing cells of the liver are called _________
Hepatocytes
Hepatocytes make up what percentage of the cellular volume of the liver?
75-80%
What makes up the portal triad?
- Portal vein
- Hepatic artery
- Bile Duct
Which liver zone is responsible for aerobic metabolism?
Periportal Zone (Zone 1) - outermost zone
What is Zone 3 of the liver called?
What is the function of Zone 3?
- Perivenous Zone ( Zone 3)
- Glycolysis/ Glucuronidation
What is the purpose of Hepatic Stellate Cells?
Respond to cytokines during inflammatory periods
Name pathological conditions that can lead to cirrhosis.
- Alcoholic liver disease
- Hep C
- Hep B
- Non-alcoholic steatohepatitis
Cirrhosis can cause the following complications:
- Portal hypertension
- Ascites
- Peritonitis
- Encephalopathy
- Cardiomyopathy
How is compensated cirrhosis determined?
- Absence of portal hypertension
- Absence of GE varices
- Absence of dysfunction
Median years of survival for compensated cirrhosis?
> 12 years
How is uncompensated cirrhosis determined?
- Presences of Ascites
- Presence of Portal Hypertension
- Presence of Variceal Hemorrhage
- Presence of Heaptic Encephalopathy
Median years of survival for uncompensated cirrhosis?
2 years
Pathology of how portal hypertension can lead to esophageal varices
- Portal Hypertension causes the release of vasodilator production (NO) and angiogenic factors.
- This will cause an increase in azygos and hemiazygos flow, leading to esophageal varices.
In esophageal varices, there is collateral circulation between the high-pressure __________ system and low-pressure ________ system.
In esophageal varices, there is collateral circulation between the high-pressure PORTAL system and low-pressure AZYGOS system.
Treatment to prevent initial bleed from esophageal varices.
- Non-selective beta blockers (propranolol, nadolol) to decrease portal hypertension
- Endoscopic band ligation
Treatment to control active hemorrhage and prevention of rebleed from esophageal varices.
- Endoscopic band ligation
- Sclerotherapy (Epi/vaso)
- Somatostatins (Octreotide)
- Replace PRBCs
How does Octreotide work?
- Octreotide will cause vasoconstriction in splanchnic circulation d/t inhibition of glucagon release (splanchnic dilator).
- Vasoconstriction will decrease blood flow → Decrease Portal Hypertension
What is the purpose of a Transjugular Intrahepatic Portosystemic Shunt (TIPS)?
- Decompress the portal circulation in patients with portal hypertension
- Catheter placed through jugular vein, between portal and hepatic vein
Indications for TIPS
- Secondary prophylaxis of bleeding varices after failed medical therapy
- Temporary relief of portal HTN while awaiting transplantation
- Treatment of refractory ascites
What are the concerns and cons of TIPS?
- High rate of shunt stenosis
- Hepatic encephalopathy (↑ waste product)
- High cost
- Lack of availability
Airway considerations for cirrhosis
- Recent GI Bleed → Full Stomach
- ↓ LOC d/t encephalopathy
- ↑ Intragastric pressure d/t ascites
CV considerations for cirrhosis
- Alcoholic cardiomyopathy → bad pump
- Altered intravascular volume d/t ascites, relative hypovolemia from fluid shift.
Pulmonary considerations for cirrhosis
- ↓ FRC
- Possible pneumonia d/t aspiration
Hematological considerations for cirrhosis
- Coagulopathy
- Thrombocytopenia
What coagulation factors does the liver produce?
- Factor I
- Factor II
- Factor VII
- Factors IX through Factor XIII
Neuro considerations for cirrhosis
Hepatic encephalopathy
Describe the volume of distribution of liver disease patients
Increase volume of distribution d/t ascites
Describe the protein binding of liver disease patients
Decrease protein binding → more circulating active drug