paracetomol overdose

Question 1

features

Answer 1

N&V
loin pain 
haematuria 
proteinuria 
jaundice 
abdo pain

Question 2

blood gas

Answer 2

severe metabolic acidosis

Question 3

pathophysiology

Answer 3

metabolism of paracetamol results in build up of toxic substance - NAPQI

glutathione inactivates NAPQI but in overdose it rapidly depletes leaving NAPQI un-metabolised

liver and kidney damage

Question 4

Mx - ingestion <1hr ago

Answer 4

activated charcoal

Question 5

when should N-acetylcysteine be offered

Answer 5

staggered overdose

plasma paracetamol concentration is on or above the treatment line

Question 6

Mx - ingestion <4hrs ago

Answer 6

wait 4hrs to take level

treat with NAC based on level

Question 7

Mx - ingestion 4-15hrs ago

Answer 7

take immediate level and treat based on this

Question 8

what bloods are needed

Answer 8

GBC
U&Es
INR
venous gas

Question 9

what constitutes staggered overdose

Answer 9

tablets were not all taken within 1hr

Question 10

inc risk of toxicity

Answer 10

• taking enzyme inducing drugs
• regular alcohol excess
• pre-existign liver disease
• malnourished

Question 11

criteria for liver transplantation

Answer 11

arterial pH < 7.3 24hrs after ingestion 
or 3/3 of
-prothrombin time >100s
-creatinine >300
-grade III or IV encephalopathy