Sat27November0445PM 12

Following a severe paracetamol overdose, which of the following is true?

(Please select 1 option)

The plasma albumin concentration is the most sensitive indicator of impending acute hepatic failure

Acute haemolytic anaemia is a recognised complication Correct

Paracetamol metabolites are scavenged by glutamine

Hyperthermia can occur

The initial clinical features provide a reliable guide to the severity of the poisoning

Explanation

Paracetamol hepatotoxicity is due to toxic oxidative metabolites combining with sulphydryl groups of hepatocyte proteins, causing centrilobular necrosis. The metabolites are usually scavenged by glutathione (not glutamine), but in a severe overdose this scavenging mechanism is rapidly overwhelmed.

Treatment is based upon N-acetylcysteine which provides additional sulphydryl groups to scavenge the toxic metabolites.

The initial clinical features of the overdose do not provide a reliable guide to the severity of poisoning, with more serious complications developing after 36 hours.

These include:

Acute haemolytic anaemia

Hypothermia

Hypoglycaemia

Metabolic acidosis

Delirium

Acute hepatic failure (AHF).

The prothrombin time is the most sensitive indicator of impending AHF (not albumin).

Do not be confused by Child's criteria, which are used to calculate or assess the operative risk in patients with portal hypertension (as serum albumin falls so the score and hence the risk are increased).

Answer Statistics

1

6%

2

44%

3

29%

4

18%

5

5%

Times answered: 284