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Hey,
One of our learning objectives this week in class was
''account for Early and late loss of consciousness with acetaminophen overdose and explain the mechanisms involved''
so this is the answer for the above that i found, however i'm confused on some parts....
Lactic acidosis is usually associated with coma....
Acetaminophen poisoning can result in lactic acidosis in two different scenarios. First, early in the course of poisoning (before the onset of hepatotoxicity); a lactic acidosis is usually associated with coma. The toxic metabolite of paracetamol, N-acetyl-p-benzo-quinone imine, (NAPQI) inhibits electron transfer in the mitochondrial respiratory chain and thus inhibits aerobic respiration. This occurs only at very high concentrations of paracetamol, and precedes cellular injury by several hours.
The second scenario in which lactic acidosis can occur is later in the course of paracetamol poisoning as a consequence of established liver failure. Lactate is elevated primarily because of reduced hepatic clearance.
My questions are:
1. How does reduced hepatic clearance cause lactate levels to increase.
and,
2. How does Lactic acidosis itself then bring about coma/ how would increased lactate levels bring about coma?
if someone could explain please, i asked in my pbl group but no one could come up with an answer.
Thanks
One of our learning objectives this week in class was
''account for Early and late loss of consciousness with acetaminophen overdose and explain the mechanisms involved''
so this is the answer for the above that i found, however i'm confused on some parts....
Lactic acidosis is usually associated with coma....
Acetaminophen poisoning can result in lactic acidosis in two different scenarios. First, early in the course of poisoning (before the onset of hepatotoxicity); a lactic acidosis is usually associated with coma. The toxic metabolite of paracetamol, N-acetyl-p-benzo-quinone imine, (NAPQI) inhibits electron transfer in the mitochondrial respiratory chain and thus inhibits aerobic respiration. This occurs only at very high concentrations of paracetamol, and precedes cellular injury by several hours.
The second scenario in which lactic acidosis can occur is later in the course of paracetamol poisoning as a consequence of established liver failure. Lactate is elevated primarily because of reduced hepatic clearance.
My questions are:
1. How does reduced hepatic clearance cause lactate levels to increase.
and,
2. How does Lactic acidosis itself then bring about coma/ how would increased lactate levels bring about coma?
if someone could explain please, i asked in my pbl group but no one could come up with an answer.
Thanks