Liver, GI, and Biliary Diseases Flashcards
(186 cards)
• Liver receives
25 -30% of the cardiac output
The Hepatic plexus is innervated by:
Sympathetic nerve fibers from T6-T11
Parasympathetic fibers from the
right and left vagus and right phrenic nerves.
Blood-cleansing function
(Kupffer Cells).
Major Physiologic Functions of the Liver
- Blood reservoir (up to 300 mls).
- Blood-cleansing function (Kupffer Cells).
- Metabolic functions
• Metabolism of fat, carbohydrates, and
proteins - Drug metabolism
• Production of plasma proteins, albumin,
and plasma cholinesterases - Bile formation/excretion
- Bilirubin Excretion
Check for liver function
PT/INR
Bilirubin
ALT
Does not measure liver function
Total bilirubin normal
<1mg/dl
>3mg scleral icterus
>4 mg overt jaundice
Alanine aminotransferase (ALT) is a
cytoplasmic enzyme highly specific to the liver.
Aspartate aminotransferase (AST) is an
enzyme that exists in hepatic and extrahepatic tissues
Most important enzymes
ALT
- When both liver enzymes are elevated, ALT/AST ratio is considered:
- < 1 =
nonalcoholic steato-hepatitis (NASH) (non-alcohol fatty liver)
• When both liver enzymes are elevated, ALT/AST ratio is considered:• 2 to 4 =
alcoholic liver disease
Portal vein is
Bigger than portal artery
Albumin • Synthesized
exclusively by hepatocytes
Severe impairment of the synthetic
capacity of the liver
• INR•
Correlated to liver dysfunction • Reliable predictive value for survival of patients c/ liver disease
• Impairment of the hepatic synthetic function of coagulation factors.
Direct correlation with liver dysfunction
INR
Risk for surgery
Screen INR
Acute Cholecystitis
Obstruction of the cystic duct or common bile duct by a
gallstone causes acute inflammation of the gall bladder
90% of gallstones are composed of
cholesterol, due to “Western diet”
Signs and symptoms of Acute cholecystitis
- Nausea and vomiting
- Fever
- Abdominal pain
- RUQ tenderness
• Severe mid-epigastric pain that moves to the RUQ and radiates to the back = biliary colic • Murphy’s sign • Dark urine • Scleral icterus
Treatment of Acute Cholecystitis
- IV fluids, opioids for pain, antibiotics for leukocytosis
- Laparoscopic cholecystectomy
- 5% of “lap choles” convert to open because inflammation obscures the anatomy
Anesthesia considerations Immediate ↓ in venous return and cardiac output ➔ ↑ MAP and systemic vascular
resistance
• Opioid induced sphincter of Oddi spasm occurs in less than 3% of patients
• Treated c/ glucagon, naloxone, or nitroglycerin
• Insufflation ➔ ↑ intra-abdominal pressure ➔interferes c/ ventilation and venous return, can result in bradycardia (glycopyrrolate vs atropine)