Page 188 - Critical Care Notes

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GI
■ Repeated environmental and hepatotoxin exposure
■ Malignancy
■ Hypoperfusion of the liver
■ Metabolic disorders: Reye’s syndrome, Wilson’s disease
■ Autoimmune disorders
■ Malnutrition, diabetes mellitus, chronic cholestatic disease, and
hypertriglyceridemia
■ Postoperatively: jejunoileal bypass, partial hepatectomy, liver transplant failure
Pathophysiology
■ Severe liver impairment such as necrosis or ↓ blood supply to liver → toxic
substances accumulating in the blood.
■ Impaired bilirubin conjugation, ↓ clotting factors, ↓ glucose synthesis,
↓ lactate clearance → jaundice, coagulopathies, hypoglycemia, and
metabolic acidosis.
■ Decreased macrophages in liver →↑ risk of infection and spleen enlargement.
■ Hypoalbuminemia, fluid and electrolyte imbalances, acute portal hyperten-
sion → development of ascites.
■ Ineffective fat metabolism →↓ bile salt production.
■ Cirrhosis: Fibrotic tissue replaces healthy liver tissue.
■ Fatty liver disease: Fatty cells replace healthy liver tissue.
■ Hepatic failure may progress to hepatic encephalopathy.
Clinical Presentation
■ Jaundice and pruritus, ascites, edema, JVD
■ Abdominal pain
■ Malnutrition, nausea, vomiting, and anorexia
■ Weakness, fatigue, and confusion
■ Hyperventilation, respiratory alkalosis, dyspnea, pleural effusion, crackles,
and hypoxemia
■ Hypokalemia and hyponatremia or hypernatremia
■ Palmar erythema, spider nevi, spider angiomas, and bruising; patient prone
to bleeding
■ Asterixis: Liver flap (patient extends arms → wrist dorsiflexes downward
involuntarily)
■ Metabolic acidosis, hypoglycemia, hypokalemia, and hyponatremia
■ Gallstones, malnutrition, light or clay-colored stools, and dark urine
■ Diarrhea and steatorrhea (fatty, greasy, foul-smelling stools)
■ Hepatic encephalopathy: Drowsiness, confusion, delirium or coma, inappro-
priate behavior, fetor hepaticus (sweet, slightly fecal breath odor), and day-
night reversal
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