2024 CPD Flashcards
Acute Liver Failure
Evidence of coagulation abnormality (INR >1.5) with any degree of mental alteration (encephalopathy) in a patient without pre-existing cirrhosis and with an illness of less than or equal to 26 weeks duration.
Patients with acute liver failure in the ED may progress to multiorgan failure unless treatment is initiated early. The cytokine release in liver failure and necrosis kicks off a systemic inflammatory response, causing vasodilation and hypoperfusion.
Acute on Chronic Liver Failure
Sudden hepatic decompensation observed in patients with pre-existing chronic liver disease and associated with one or more extrahepatic organ failures
Decompensated Cirrhosis
A decompensating event is defined as any of the following 4 events:
Ascites Gastrointestinal bleeding Hepatic encephalopathy Bacterial infection
Portal Hypertension
Acute Decompensation Liver Failure
Portal Hypertension is a conditon of increased hydrostatic pressure in the portal vein.
This causes reflex dilation of splanchic arteriolae, and via circulatory dysfunction to vasodilation of periepheral arteries.
This can lead to esophageal, gastric and rectal varicies.
What causes gastrointestinal bleeding in liver failure?
Spontaneous rupture of varix, ascites owing to hydrostatic pressure itself or spontaneous bacterial peritonitis owing to a leaky intestinal barrier.
Systemic Inflammation
Liver Failure
C-reactive protein and leukocytes as biomarkers of Systemic inflammation are higher in patients with pre-ACLF.
In ACLF the inflammatory response is more pronounced.
Metabolic Dysfunction
Liver Failure
SI and AD cause hypermetabolic states in which micronutrients such as glucose, amino acids and fatty acids are preferentially held available for immune cells with high metabolic demand.
Deprivation of nutrients can lead to mitochondrial dysfunction in the kidney, heart and liver.
Proven Bacterial Infections
Liver Failure
Bacterial infections with an identifiable source meaning postive cultures.
Inappropriate antimicrobial therapy is associated with development of ACLF and increased mortality.
Patients with liver cirrhosis have an increased susceptibility to bacterial infections due to a compromised immune system, portal hypertension due increased portal venous flow and hepatic resistance, thrombosis due to complex alterations in the coagulation factors and hypoalbuminemia, and bleeding due to portal hypertension as well as complex alterations in the coagulation factors .
Multidrug-Resistant Infections
Liver Failure
Multidrug-resistant gram negative bacteria are more common in ACLF.
Severe Alcoholic Hepatitis
Dysfunction to the immune system, dysfunctional neutrophils.
Contributes to mitochrondial dysfunction.
Acute Liver Failure
Supportive Care
Intravenous fluids and maintenance of acid base levels and normal electrolytes.
Vasopressors to maintain a MAP greater than 75 mm Hg to ensure renal and cerebral perfusion.
Monitor hematocrit for any bleeding, as patients have coagulopathy and poor platelet function. Patients should be started on proton pump inhibitors for prohylaxis of gastrointestinal bleed.
Maintain 1.0 to 1.5 grams of protein per kilgram per day.
Renal Failure
Liver Failure
Continuous renal replacement therapy is preferred to hemodialysis.
Meabolic Disorder
Liver Failure
Hypoglycemia occurs due to impaired gycogen production and gluconeogenesis.
D10W or D20W infusion should be used.
Alkalosis in ALF is due to hyperventilation and acidemia below pH 7.3.
Cerebral Edema
Liver Failure
Most common cause of death in ALF is cerebral edema which leads to intracranial hypertension, ischemic brain injury and herniation.
Caused by accumulation of ammonia.
Consider hypertonic saline and target Sodium of 145 - 150 mmol/L
Liver Enzymes
Liver Enzymes include AST, ALT, ALP, and GGT and the measured levels indicate degree of cell death/damage to the liver.
Liver Function Tests
Liver function tests include INR, PTT, Albumin, and Bilirubin and indicates the synthetic capability of the liver.
What Liver Function Tests are elevated due to hepatocellular damage?
ALT & AST
What Enzymes are elevated due to cholestatic damage?
ALP and GGT
Elevated when there is a problem with the flow of bile from the liver to the small intestines.
Common disease states that cause acute liver failure.
Acetaminophen toxicity
Drug induced liver injury
Viral hepatic diseases
Autoimmune diseases
Mushroom toxicity
Wilson’s disease
Non-Dihydropyridine Calcium Channel Blockers
Non-Dihydropyridine CCBs (Verapamil and Diltiazem) tend to cause myocardial suppression more than vasodilation. Typical presentation includes early development of hypotension and bradycardia.
Dihydropyrindine Calcium Channel Blockers
Dihydropyridine CCBs (Nifedipine, Amlodipine, etc.) initially cause vasodilation. However, at high doses lose selectivity for the vasculature and suppress the myocardium
How is glucose affected in calcium channel blocker toxicity versus beta-blocker toxicity?
CCB poisoning usually causes hyperglycemia, whereas BBl poisoning may cause hypoglycemia.
Lipophilic agents (propranolol)
Toxicity Issue
More likely to enter the brain and cause delirium or seizure.
Cardiac Sodium Channel Blockers
Toxicity Issues
(acebutolol, betaxolol, carvedilol, oxprenolol, pindolol, propranolol)
May cause QRS widening and monomorphic VT. EKGs may also reveal a Brugada pattern.
Hypotension can be more severe than one would expect, based solely on the degree of bradycardia.
