Hepatic Diseases (Exam III- Mordekai Edits) Flashcards
How much blood is contained in the liver at any given time?
1L
What positioning is often necessary to gain access to liver? (imaging, biopsy, etc.)
Trendelenburg
How much bile is produced by the gallbladder daily?
500mls
What patient populations most often have their gallbladder removed?
- Pregnant
- Obese
What reasons would one have for doing an open cholecystectomy vs a laparoscopic cholecystectomy?
- Necrotic gallbladder
- Surgeon practice (lol)
What is the most serious source of local bleeding encountered in cholecystectomies?
Cystic Artery
What are common s/s & tx of cholelithiasis?
-Gallstones
- Murphy’s sign
- RUQ pain, referred to shoulders
- ↑WBCs
Tx: IVF, abx, pain management, lap-chole
What is Bud-Chiari syndrome?
What are the s/s?
Obstruction of the venous outflow of the liver.
- ABD pain
- Ascites
- Hepatomegaly
What is a normal portal vein pressure?
7-10 mmHg
What pressure is seen with portal vein hypertension?
> 20-30 mmHg
What is a normal pressure in the venous sinusoids?
0 mmHg
What pressure is seen in the venous sinusoids of a portal hypertension patient?
5 mmHg
How is hepatic artery perfusion pressure calcuated?
HAPP = MAP - HVP
HAPP = hepatic artery perfusion pressure
HVP = Hepatic vein pressure
What blood coagulation factors are dependent on vitamin K for synthesis?
2, 7, 9, 10
What is the name of factor two?
Prothrombin
What clotting factors are not produced by the liver?
- III
- IV
- VIII
- vWF
What is the name of factor 3?
Tissue thromboplastin
What is the name of factor 8?
vWf (von Willebrand factor)
What is the name of factor 4?
Calcium
What drug is given intra-operatively that “opens up” the gallbladder?
Glucagon
What conditions/drugs/positions/etc increase hepatic blood flow? (6)
- Eating
- Glucagon
- β-agonists
- Recumbent position
- Acute hepatitis
- Hypercapnia
What conditions/drugs/etc decrease hepatic blood flow?(8)
- Anesthetics
- Surgical trauma
- α-agonists
- β-blockers
- PEEP
- Vasopressin boluses
- Cirrhosis
- Hypocapnia
Product of what? Direct vs indirect
Bilirubin
- Degredation product of Hgb
- Unconjugated (indirect): Imbalance between bilirubin synthesis & conjugation
- Conjugated (direct): Caused by an obstruction, causing reflux of conjugated bilirubin into circulation
What are normal bilirubin levels?
< 1mg/dL
At what bilirubin level would one see scleral icterus?
3 mg/dL
At what bilirubin level would one see jaundice?
> 4 mg/dL
The liver aminotransferases are primarily involved in what?
Gluconeogenesis
NALD AST/ALT Ratio
Usually 1:1
Alcoholic Liver Disease AST/ALT Ratio
Atleast 2:1
If AST/ALT are both elevated and there is a ratio of >4 then what disease is suspected?
Wilson’s disease
Sx? Labs? Tx?
What is Wilson’s disease?
- Impaired copper metabolism, build-up in liver
-Leads to oxidative stress in liver, basal ganglia, and cornea - Autosomal recessive disease
- Sx: Asymptomatic to sudden onset liver failure, neurological & psychiatric manifestations
- Labs: Urine copper level, aminotransferases, serum cerulopasmin
- Tx: Copper-chelation & oral zinc to bind copper
Cholestatis Elevated Labs
High Alk. Phosphatase
GGT
Bilirubin
Which liver transaminase is more specific to the liver?
ALT (alanine transaminase)
Which liver transaminase is found in mitochondria and the cytosol?
AST (aspartate transaminase)
Which of the liver transaminases has a longer half-life?
AST (36hrs)
ALT (18hrs)
What would be considered a minor increase in AST & ALT?
What would be indicated by this?
< 100 IU
- Hep B & C
- Non-alcoholic disease
- Fatty liver
What would be considered a moderate increase in AST & ALT?
What would be indicated by this?
100 - 300 IU
- Alcoholic hepatitis
- Autoimmune hepatitis
- Acute viral hepatitis
Four conditions/factors listed
What would be considered a marked/severe increase in AST & ALT?
What would cause this?
> 300 IU
- Drugs
- Acute viral hepatitis
- Ischemia
- Extrahepatic cholestasis
What are normal AST values?
ALT?
AST = 10 - 40 IU/L
ALT = 10 - 50 IU/L
What is a normal prothrombin time?
12 - 14 seconds
What liver lab is sensitive for acute injury?
PT (prothrombin time)
What liver lab is not sensitive for acute injury?
Albumin
How long could it take to go from jaundice to 80-90% loss of liver function?
4 weeks
What are the four grades of encephalopathy?
- Behavioral changes, minimal LOC changes.
- Disorientation, drowsiness, inappropriate behavior.
- Marked confusion, incoherence, somnolent.
- Comatose.
What are the s/s of hepatorenal syndrome?
- H₂O retention
- Azotemia
- ↓ Na⁺
- Oliguria
What pharmacokinetic changes in liver patients necessitate decreases in drug dosing?
- ↑ VD
- ↓ plasma-protein binding
- ↓ drug clearance
How is Hepatitis A spread?
Fecal matter contact w/ food and water.
What are the s/s of Hep A?
Asymptomatic to full liver failure
How is Hep A treated?
Pooled gamma globulin
What is the leading cause of liver cancer?
Hepatitis B
Who most often develops chronic infection from hepatitis B?
Children
What is the treatment for Hep B?
Hepatitis B immunoglobulin
What is the leading cause for liver transplantation?
Hepatitis C
How is Heptatitis C treated?
- Sofosbuvir
- Interferon w/ ribavirin
- other antivirals
Hepatitis D occurs in conjuction with what?
Hepatitis B
What treatments exist for Hepatitis E?
NO treatments, usually self-limiting
What is the most common cause of acute liver failure in the US?
Acetaminophen
How is acetaminophen-induced acute liver failure treated?
N-acetylcysteine within 8 hours
What compound(s) of halothane metabolism contributes to hepatocellular injury?
- TFA (trifluroacetic acid)
- Fluoride
What is the MELD score?
Model for End-Stage Liver Disease Score
(predicts mortality based on symptomology).
A MELD score of > 40 means what?
100% mortality in the hospitalized patient.
A MELD score < 10 is indicative of what for a preoperative patient?
Safe to undergo elective surgery.
A MELD score 10-15 is indicative of what for a preoperative patient?
Needs optimization to undergo elective surgery.
A MELD score >15 is indicative of what for a preoperative patient?
Elective surgery is contraindicated.
What are the coagulative effects of cirrhosis?
Increased risk of bleeding and clotting
What are the pulmonary effects of cirrhosis?
Chronic Lung Disease and SOB from fluid retention and ascites.
Why does hepatic encephalopathy occur?
Accumulation of ammonia
What is the goal Hgb for acute variceal bleeding?
Hgb = 8 mg/dL
What volatile is best for liver surgeries?
Sevoflurane
What result does hypocapnia have on hepatic blood flow?
Hypercapnia?
↓ PaCO₂ = ↓ HBF
↑ PaCO₂ = ↑ HBF
What portion of the clotting cascade does warfarin affect? What test measures warfarin effect?
- Warfarin
- Extrinsic pathway
- Prothrombin
- Time
Normal? Clinically significant for portal HTN? Variceal Rupture?
Hepatic Venous Pressure Gradient
9 Risk Factors, 7 physical exam factors
Physical Liver Function Assessment & Risk Factors
Labs (7) & Imaging
Hepatobilliary Function Tests
Labs
* BMP, CBC
* PT/INR
* AST
* ALT
* Bilirubin
* Alkaline Phosphatase
* GGT
Imaging
* Ultrasound
* Doppler (portal blood flow)
* CT/MRI
10
Functions of the Liver
Transmission, Incubation, Serum Antigen/Antib body test
Characteristics of Viral Hepatitis
Course, prevention after exposure, mortality
9 symptoms, 5 lab values
Symptoms & Lab Values of ALD
Dx, gold standard, treament, when is transplant indicated?
NAFLD
- Dx: Hepatocytes contain >5% fat
- Liver biopsy is gold standard in distinguishing NAFLD and other liver diagnoses.
- Treatment: Diet, exercise
- Liver transplant indicated for: advanced fibrosis, cirrhosis and related complications
Affects who? AST/ALT? Tx? Remission %? Transplant when?
Autoimmune Hepatitis
- Predominantly affects women
- Can be asymptomatic, acute, or chronic
- Body produces antibodies against liver
- Ast/Alt can be 10-20x normal
- Tx: Steroids, azathioprine
- 60-80% achieve remission; although, relapse is common
- Liver transplant indicated when all treatments fail and acute liver failure ensues
What is it? #1 cause of what? Neutrophil elastase? Dx? Tx?
Alpha-1 Antitrypsin Deficiency
- Genetic disorder; defective alpha-1 antitrypsin protein
- This protein protects the liver & lungs from neutrophil elastase; an enzyme that disrupts tissues in the lungs and liver - # 1 genetic cause of liver transplant in children
- Dx: Alpha-1 antitrypsin phenotyping
- Tx: Pooled a-1 antitrypsin is effective for pulmonary symptons, but not liver
- Liver transplant only curative option
Pts present with? Lab values? Imaging that can be done? Tx?
Hemochromatosis
- Excessive intestinal absorption of iron; accumulates in organs
- Genetic or caused by repetitive blood/iron transfusions
- Pts present with cirrhosis, heart failure, DM, adrenal insufficiency, or polyarthropathy
- Elevated AST/ALT, transferrin saturation, and ferritin
- Echo & mri can dx cardiac/liver abnormalities
- Tx: Weekly phlebotomy, iron-chelating drugs, liver transplant
Fibrosis happens where? Sx? Dx? Tx? Labs? Vitamin Deficiencies?
Primary Sclerosing Cholangitis
- Autoimmune, chronic inflammation of larger bile ducts
- Intra & extrahepatic
- Fibrosis in biliary tree (beads on string appearance on mri)–> cirrhosis –> end stage liver disease
- Sx: Fatigue, itching, deficiency of fat-solube vitamins (A,D,E,K) cirrhosis
- Labs: High alk. phosphatase, GGT, +auto-antibodies
- Dx: MRCP or ERCP to see dilated bile ducts
- No effective tx, liver transplant
- Recurrence after transplant is common due to auto-immune nature
Sx? Labs? Imaging to r/o what? Biospy shows what? Tx?
Primary Biliary Cholangitis
- Biliary Cirrhosis
- Autoimmune, destruction of bile ducts w/periportal inflammation & cholestasis;
-Thought to be caused from exposure to toxins in genetically susceptible individuals - Liver scarring, fibrosis, cirrhosis
- Sx: Jaundice, fatigue, itching
- Labs: High alk phos, GGT, anti-mitochondrial antibodies
- CT,MRI,MRCP to r/o bile duct obstruction
- Biopsy will show bile duct infiltration w/lymphocytes
- No treatment, slow progression
Labs? Causes? Sx? Tx?
Acute Liver Failure
- Life-threatening sever liver injury
- Rapid increase in AST/ALT, AMS, coagulopathy
- 50% of cases are drug induced
- Other causes: Viral hepatisis, autoimmune, hypoxia, ALF of pregnancy, HELLP syndrome
- Massive hepatocyte necrosis
- Jaundice, n/v, RUQ pain, cerebral edema, encephalopathy, multi-organ failure, death
- Tx the cause, supportive care, liver transplant
Common causes? Tx?
Cirrhosis
- Final stage of liver disease
- Scar tissue replaces normal liver tissue
- Thrombocytopenia
- Transplant is only cure
- Common causes: ALD, NAFLD, Hep B & C
5 Listed Here
Complications of Cirrhosis
- Portal HTN:
-HVPG >5, increased vascular resistance in portal venous system - Ascites:
-Portal HTN leads to increased blood volume & peritoneal accumulation of fluid
-Low salt diet, albumin replacement, TIPS - Bacterial Peritonitis
- Varices
-Hemorrhage is most lethal complication. Banding, ligation, balloon tamponade - Hepatic Encephalopathy:
-Buildup of nitrogenous waste
-Lactulose, Rifaximin to reduce ammonia- producing bacteria in gut
Hepatorenal, Hepatopulmonary, Portopulmonary Syndromes
- All complications of cirrhosis
Hepatorenal:
* Excess production of endogenous vasodilators (NO,PGS)–> decreased SVR and RBF
* Tx: Midodrine, Octreotide, Albumin
Hepatopulmonary:
* Triad of chronic liver disease, hypoxemia, and intrapulmonary vascular dilation
* Platypnea- hypoxemia when upright d/t R-L intrapulmonary shunt
Portapulmonary HTN:
* Pulm HTN accompanied by portal HTN
* Systemic vasodilation triggers production of pulmonary vasoconstrictors
7 Total: Preop labs, high risk for what? Fluids? ETOH?
Anesthesia Considerations in Liver Disease
Succs/Nimbex?
- Pre-op labs: CBC, BMP, PT/INR, Type & Screen
- High risk for aspiration, HoTN, hypoxemia
- Give colloids
- Alcoholism increases the MAC requirement of volatiles
- Drugs will have slow onset/prolonged DOA
- Succs and Nimbex ideal; however, plasma cholinesterases may be decreased in severe liver
- Bleeding/coag management
What is it? Indications? C/I?
TIPS
Transjugular Intrahepatic Portosystemic Shunt
* Stent/graft placed between hepatic vein and portal vein
* Shunts portal flow to systemic circulation & reduces portosystemic pressure gradient
Indications:
* Refractory variceal hemorrhage
* Refractory ascitse
C/I:
* Heart Failure
* Tricuspid Regurg
* Severe pulmonary HTN
What is it? Anesthesia Considerations (IV, monitoring, CVP, PCA)
Partial Hepatectomy
Surgeons may need to clamp what?
- Resection to remove neoplasms, but leaving enough tissue for regeneration
- Up to 75% tissue removal in patients w/ normal liver function
- Often causes post-op coagulation disturbances
Anesthesia Considerations
* Invasive monitoring
* Blood products
* Adequate vascular access
* Standard practice to maintain low CVP prior to resection to reduce blood loss
* Often require post-op PCA
Surgeons may clamp IVC or hepatic artery to control blood loss
Types of donors? Inra-op necessities?
Liver Transplant
- Only definitive treatment for ESLD
- Alcoholic LD is most common indication
- Living donor; surgeries timed together to minimize ischemic time
- Braid dead donors: Organs kept HD stable to maintain orgfan perfusion
Intra-op:
* A-line, CVC, PA Cath, TEE
* Pressors & inotropes ready
* Coagulation
Billiary Tree
1. Gall Bladder
2. Cystic Duct
3. Bile Duct
- Portal Vein
- Hepatic Artery
- Inferior Vena Cava
- Hepatic Duct
- Right posterior section
- Right anterior section
- Left medial section
- Left lateral section
Segments? Sections? What branch into each segment? 3 hepatic veins?
Liver Anatomy
How does bile travel
- 8 segments, four sections, based on blood supply & bile drainage
- R & L lobes separated by falciform ligament
- Portal vein and hepatic artery branch into each segment
- 3 hepatic veins empty into IVC
-Right, middle, and left hepatic veins - Bile ducts travel along portal veins
- Bile drains through hepatic duct and common bile duct
- Bile enters duodenum via Ampulla of Vater
CO received? Portal vein vs Hepatic Artery? O2 delivery?
Liver Perfusion
- Receives 25% of CO via portal vein and hepatic artery
- Highest proportionate CO of all organes
Portal Vein:
* Arises from splanchnic vein and superior mesenteric vein
* Partially deoxygenated because it has already perfused GI organs, pancreas, & spleen
* Provides 75% of hepatic blood flow
Hepatic Artery
* Branches off aorta
* Provides 25% of hepatic blood flow
O2 delivery
* 50% partially deoxygenated from portal vein
* 50% from hepatic artery
How does this happen? What does it lead to?
Portal HTN
- Hepatic blood flow is autoregulated and inversely related to portal venous flow
- Hepatic artery dilates in response to low portal venous flow, keeping HBF consistent
- Increased portal venous pressure leads to blood backing up in the systemic circulation –> causing esophageal and gastric varices
S/S, Tx
Choledocolithiasis
- Stone is obstructing common bile duct
- N/V, cramping, RUQ pain, jaundice, fever, rigors
- Tx: ERCP
What is it? Anesthesia? Position? Spasm?
ERCP
Endoscopic Retrograde Cholangiopancreatography
* Endoscopist threads guidewire through Sphincter of Oddi, into Ampulla of Vater to retrieve stone
* General anesthetic, prone, left table tilt, ETT taped to left
* Opioids cause spasm of Sphincter of Oddi- Glucagon may be require
