Overdoses

Question 1

define paracetamol overdose

Answer 1

an excessive ingestion of the medication paracetamol

Question 2

clinical features of paracetamol overdose

Answer 2

can be asymptomatic but can also present with:

nausea + vomiting 
loin pain 
haematuria and proteinuria 
jaundice 
abdominal pain 
coma 
metabolic acidosis

Question 3

physiology of paracetamol overdose

Answer 3

paracetamol metabolism causes build up of toxic substance NAPQI to cause liver and kidney damage

Question 4

management of paracetamol overdose if <1hr of ingestion and dose taken >150mg/kg

Answer 4

activated charcoal

Question 5

management of paracetamol overdose if staggered or ingestion >15hrs ago

Answer 5

start N-acetylcysteine (NAC) immediately

Question 6

management of paracetamol overdose <4hrs ago

Answer 6

wait 4hrs to take bloods/nomogram and treat with N-acetylcysteine based on level

Question 7

management of paracetamol overdose 4-15hrs ago

Answer 7

take immediate bloods and treat based on results

Question 8

bloods required in paracetamol overdose

Answer 8

FBC
U+Es
INR
venous gas

Question 9

patients with increased risk of toxicity include

Answer 9

those on long-term enzyme inducers
regular alcohol excess
pre-existing liver disease
glutathione-deplete states (HIV, EDs, malnutrition)

Question 10

define TCA overdose

Answer 10

an excess ingestion of TCAs (noradrenaline and serotonin reuptake inhibitors)

Question 11

clinical features of TCA overdose

Answer 11

drowsiness 
confusion 
arrhythmias 
seizures 
vomiting 
headache 
flushing 
dilated pupils

Question 12

investigations for TCA overdose

Answer 12

bloods (FBC, CRP, U+Es, LFTs and VBG)

ECG (may show prolonged QT interval)

Question 13

management of TCA if ingestion 2-4hrs ago

Answer 13

activated charcoal

IV sodium bicarbonate

Question 14

additional management of TCA overdose

Answer 14

consider review by ICU or renal replacement therapy if severe metabolic acidosis