Final_Hepatic

Question 1

Hepatic blood flow is provided by

Answer 1

hepatic artery + portal vein (dual afferent blood supply)

Question 2

Hepatic arterial blood flow is controlled by

Answer 2

arterial smooth muscle and autonomic regulation

Question 3

Reduction in portal vein flow is compensated by

Answer 3

hepatic arterial buffer response

Question 4

Acute liver failure - signs and symptoms

Answer 4

● Fatigue
● Lethargy
● Anorexia
● Nausea/ vomiting
● Jaundice
● RUQ tenderness
● Change in liver span
● Ascites
● Encephalopathy
● Cerebral Edema (↑ICP)

Question 5

Hepatic drug metabolism

Answer 5

Hepatic biotransformation

○ Phase I: + oxygen or - hydrogen carried out by mixed function oxidase (Oxidation, Reduction, Hydrolysis (involves breaking of ester bonds))

○ Phase II: Involves conjugation of active metabolites with glutathione, sulfate, glycine or glucuronic acid into inactive substrates (Conjugation)

• Hepatic Microsomal Enzymes – CYP450
• inducers: ETOH, phenobarb, st johns wort
• inhibitors: Cimetidine, ritonivir, grapefruit juice, CCBs, erythromycin, itraconazole, nefazodone

Question 6

normal hepatic blood flow is

Answer 6

25% of CO

Question 7

portal vein flow is

Answer 7

not regulated

-vulnerable to: systemic HOTN, dec CO

Question 8

reduction in portal vein flow is compensated by

Answer 8

hepatic arterial buffer response

Question 9

hepatic arterial buffer response

Answer 9

○ ↓ portal vein flow leads to ↑ hepatic arterial flow

○ Stimulated by ↓ pH + O2 levels, ↑ CO2

Question 10

portal vein

Answer 10

• Supplies 3x blood flow as hepatic artery (75% of blood flow)
• Venous blood - but still supplies 45-50% O2 to liver

Question 11

portal triad

Answer 11

• hepatic artery
• hepatic portal vein
• bile duct

Question 12

Hepatitis etiology

Answer 12

Chronic Liver disease - one cause = Chronic viral hepatitis

• Persistent hepatic inflammation > 6 m
• result of infxn with hepatitis B or C

Question 13

Chronic Liver disease - categories

Answer 13

1. Cirrhosis of the liver
   a. Functioning liver tissue replaced by scar tissue
   b. Progressive decrease in hepatic blood flow
2. Fibrosis of the liver
   a. Overgrowth of scar tissue d/t infxn, inflammation, injury, or healing
   b. Can inhibit the organs proper functioning

Question 14

chronic liver disease - s/s

Answer 14

-Non-specific symptoms (Anorexia, weight loss, weakness, fatigue)
- Jaundice
○ Portal HTN → diverts blood away from liver, lower albumin levels → lead to a buildup of bilirubin → causes jaundice
○ Normally: RBCs broken down in spleen into indirect bilirubin (very lipid soluble, hard for kidneys to remove) → indirect bilirubin goes to liver for conjugation → turns into direct bilirubin
○ Direct bilirubin: water soluble, easy for kidneys to remove
○ Albumin = plasma protein that binds to direct bili, keep in circulation
○ ↓albumin levels + ↑bilirubin → leaking bilirubin→ jaundice
- Spider angioma
- Palmar erythema
- Hepatomegaly
- Splenomegaly

Question 15

gastroesophageal varices

Answer 15

-Can lead to massive bleeding r/t portal hypertension
-Varice - large vein that became distended d/t collapsed valves
-Major cause of morbidity and mortality
Can Precipitate Encephalopathy From Blood In GI tract
(Risk of GI bleed → upper GI bleed → digesting too much protein (blood) → hepatic encephalopathy)
-Management: Balloon tamponade, vasopressin, somatostatin (octreotide), propranolol
-Sclerotherapy, variceal banding/hemoclip, electrocoagulation

Question 16

complications of liver disease

Answer 16

• hyperdynamic circulation
• gastroesophageal varices
• hepatic encephalopathy
• pulm: hepatopulmonary syndrome, portopulmonary HTN
• ascites
• hematologic: anemia, thrombocytopenia leukopenia, coag factor deficiencies
• renal: hepatorenal syndrome, hyponatremia/hypokalemia
• hypoalbuminemia

Question 17

perioperative anesthetic management of liver disease - goal

Answer 17

preserve hepatic blood flow/existing hepatic function

Question 18

perioperative anesthetic management of liver disease - premedication

Answer 18

○ Judicious use of sedatives (or skip)—may prolong CNS depression + worsen hepatic encephalopathy
○ For EtOH patients: Need benzodiazepines

Question 19

perioperative anesthetic management of liver disease - induction

Answer 19

○RSI for ascites, delayed gastric emptying (intoxicated), bleeding
○ Propofol induction followed by IAs
○ Induction may cause profound HOTN (IV volume replacement, small dose of pressors)

Question 20

perioperative anesthetic management of liver disease - maintenance

Answer 20

○ Sevo-, iso- and des- have limited liver metabolism
○ Opioids should be used judiciously (Remifentanil)
○ Cisatracurium or atracurium for NMB maintenance

Question 21

perioperative anesthetic management of liver disease - emergence

Answer 21

○ Slower emergence + return of neuromuscular fxn d/t reduced ability to clear Rx
○ At risk for aspiration must be wide awake prior to extubation
○ Postop intubation if altered LOC

Question 22

Liver failure is most common cause of

Answer 22

postop death in patients with cirrhosis

Question 23

_____ is increased in cirrhotic patients

Answer 23

periop mortality

Question 24

Goals for periop (liver failure)

Answer 24

○ Maintain liver perfusion and oxygenation
○ Avoid NG/OG tubes (risk of variceal bleed)
○ Avoid LR, use colloids
○ Benzos for Etoh patients
○ Consider admitting to ICU after intermediate or high-risk procedure

Question 25

Liver biotransformation reactions involve all of the following EXCEPT...
○ Auto-oxidation
○ Conjugation
○ Hydrolysis
○ Oxidation
○ Reduction

Answer 25

Auto-oxidation

Question 26

● Jaundice may result from all of the following EXCEPT…
○ Defects in bilirubin conjugation
○ Excessive production of bilirubin
○ Increased uptake of bilirubin into hepatic cells
○ Intrahepatic obstruction of ducts
○ Gilbert’s disease

Answer 26

Increased uptake of bilirubin into hepatic cells

Question 27

● Hepatic blood flow….
○ Is closely regulated by dopamine
○ Is closely regulated during surgery and anesthesia
○ Is decreased with sympathetic stimulation
○ Increases with arterial hypoxemia
○ Responds slowly to bodily needs

Answer 27

Is decreased with sympathetic stimulation

Question 28

● Unconjugated bilirubin...
○ Breaks down to biliverdin
○ Is conjugated with glucuronic acid
○ Is nontoxic
○ Is secreted into the intestinal tract
○ Is the product of white cell breakdown

Answer 28

Is conjugated with glucuronic acid

Question 29

● Ascites…
○ Follows chronic decreased portal vein pressure
○ Follows periods of hyperalbuminemia
○ Is usually accompanied by hypernatremia
○ May have adverse cardiopulmonary effects
○ Should be removed rapidly to avoid reaccumulation

Answer 29

May have adverse cardiopulmonary effects

Question 30

● In the patient with cirrhosis…
○ Excessive sodium is lost in the urine
○ Less thiopental is required for induction
○ Pancuronium is more effective
○ Serum gamma globulin level will be low
○ The serum albumin level will be elevated

Answer 30

Less thiopental is required for induction

Question 31

● The patient with acute viral hepatitis…
○ Is an acceptable candidate for general anesthesia for elective surgery
if the degree of liver enzyme elevation is mild
○ Is at high risk for perioperative mortality
○ Is not affected by surgical procedures
○ Should have an inhalational induction to avoid thiopental
○ Should never have a general anesthetic

Answer 31

Is at high risk for perioperative mortality

Question 32

Albumin…
○ Has a half-life of approximately 3 weeks
○ Is necessary for maintenance of oncotic pressure
○ Is the major plasma protein
○ Levels are lower in a neonate

■ Select all that apply

Answer 32

○ Has a half-life of approximately 3 weeks
○ Is necessary for maintenance of oncotic pressure
○ Is the major plasma protein
○ Levels are lower in a neonate

Question 33

The blood supply to the liver is by two vessels, the hepatic artery and portal vein. These vessels differ in that …
○ 60% of the blood supply comes from the hepatic artery
○ The portal vein blood is more fully saturated than the hepatic artery
○ The portal vein provides 50% of the oxygen supply
○ The portal vein supplies the bulk of the nutrients to the liver

■ Select all that apply

Answer 33

○ The portal vein provides 50% of the oxygen supply
○ The portal vein supplies the bulk of the nutrients to the liver

*The liver has a dual blood supply. Only 25% of the blood is supplied by the hepatic artery. The oxygen supply is evenly divided by the two vessels, even though the portal vein blood is more Unsaturated. Most of the nutrients come from the portal vein.

Question 34

The autoregulation of the hepatic blood flow…
○ Involves the hepatic artery
○ Involves the portal vein
○ Is via the sympathetic nervous system
○ Is via the parasympathetic nervous system

Select all that apply

Answer 34

○ Involves the hepatic artery

○ Is via the sympathetic nervous system

Question 35

ALF is seen in which race the most? Least?

Answer 35

Acute liver failure is seen among all races
Most: Whites
Least: Latin Americans

○ Whites (74%)
○ Hispanics (10%)
○ Asians (5%)
○ African Americans (3%)
○ Latin Americans (2%)

Question 36

hepatitis A etiology

Answer 36

contaminated food/water

Question 37

hepatitis B etiology

Answer 37

infected blood, needles, unprotected sex

Question 38

hepatitis C etiology

Answer 38

blood + needles

Question 39

hepatitis D etiology

Answer 39

infected blood, needles, unprotected sex

-must be + hepB

Question 40

Hepatitis E etiology

Answer 40

contaminated water