Overdose

Question 1

What resource is good to look up management of OD?

Answer 1

TOXBASE

Question 2

Paracetamol OD causes the build up of what toxic metabolite?

Answer 2

NAPQI

Question 3

Define a staggered OD

Answer 3

OD taken over >1 hour

Question 4

What amount of paracetamol = significant toxicity?

Answer 4

> 150 mg/kg

Question 5

Give 2 factors increasing the risk of liver damage in paracetamol OD

Answer 5

Malnutrition and alcohol (previous damage)

Question 6

How may paracetamol OD present (<24 hours)

Answer 6

Nausea, vomiting, sweating

abdo pain?

Question 7

What are the late signs of paracetamol OD? (i.e. if untreated)

Answer 7

Liver failure!!

Jaundice, confusion, coagulopathy, hypoglycaemia

After 3-5 days

Question 8

When should you measure plasma levels of paracetamol

Answer 8

After 4 hours

Question 9

If someone presents <1 hour post-paracetamol OD, what can you give them?

Answer 9

Activated charcoal 1g/kg

Question 10

What do you give for paracetamol OD as soon as you get the 4 hour reading back?

Answer 10

NAC (N-acetylcysteine)

Question 11

When is NAC most effective?

Answer 11

<8 hours

Question 12

How is NAC given?

Answer 12

24 hour infusion

Question 13

How does NAC work?

Answer 13

Increases the amount of glutathoine so NAPQI can be broken down

Question 14

Do you still give NAC if paracetamol OD presents late?

Answer 14

YES!!

Question 15

Someone presents 8-24 hours post-paracetamol OD - what do you give them?

Answer 15

NAC straight away!

If the amount is >150mg/kg, even before the serum conc comes back

Question 16

How do you manage a staggered OD?

Answer 16

Give NAC immediately if amount >150 mg/kg - serum levels not reliable in this context

Question 17

What triclyclic is most likely to cause lethal intoxication?

Answer 17

1st generation (e.g. amitriptyline)

Question 18

What are the anti-cholinergic features of tricyclic OD?

these present early

Answer 18

Dry mouth
Dilated pupils
Tachycardia
Urinary retention
Myoclonic jerks
Blurred vision
Hypotension

Question 19

Is the response in tricyclic OD sympatetic or parasympathetic?

Answer 19

SYMPATHETIC response because it blocks parasympathetic

Question 20

What are the effects of blocking sodium channels in tricyclic OD?

Answer 20

Cardiac arrhythmias + seizures

Question 21

What are the features of severe tricyclic OD?

Answer 21

coma, respiratory depression, hypoxia, metabolic acidosis

Question 22

What amount of tricyclic can cause death?

Answer 22

1000mg

Question 23

ECG changes in tricyclic OD

Answer 23

Broad QRS (seen before ventricular arrhythmias occur)
Tachycardia
Torsardes de pointes

Question 24

What would an ABG indicate in tricyclic OD?

Answer 24

metabolic acidosis

Question 25

What is the general approach to any OD?

Answer 25

ABCDE!

Question 26

What is the initial management of tricyclic OD if there are ECG changes?

Answer 26

IV sodium bicarbonate!! | for prolonged QRS

Question 27

What would you do if someone presents <1 hour of tricyclic OD with NO ECG changes?

Answer 27

Gastric lavage/ activated charcoal (50g) N.B. Always give the bicarb first if there are ECG changes

Question 28

How would you treat seizures in tricyclic OD?

Answer 28

IV benzos e.g. 5-10mg diazepam

Question 29

If arrhythmias persist after giving bicarb, what else can be given?

Answer 29

lidocaine

Question 30

Give 2 examples of amphetamines

Answer 30

MDMA | Speed

Question 31

How does amphetamine OD present? (sympathomimetic)

Answer 31

Dilated pupils Hyperthermia Hypertension Hyperthermia

Question 32

How does amphetamine OD present? (central effects)

Answer 32

Agitation Paranoia Seizures

Question 33

Give complications of amphetamine OD

Answer 33

intracranial haemorrhage Vasospasm DIC AKI

Question 34

What is creatinine kinase a sign of in tricyclic/ amphetamine OD?

Answer 34

Rhabdomyolysis

Question 35

What body temperature is a poor progostic factor in amphetamine OD?

Answer 35

Hyperpyerxia >42

Question 36

What would you give to control seizures/ agitation in amphetamine OD?

Answer 36

5-10mg diazepam or 1-2mg lorazepam

Question 37

In amphetamine OD what would you give if someone is psychotic?

Answer 37

Haloperidol

Question 38

In amphetamine OD, if indicated how would you manage temperature control?

Answer 38

Cool with sponge /chilled IV fluids Chlorpromazine: can help lower temp, may lead to hypotension + sedation

Question 39

How may somoene with opiate OD present?

Answer 39

``` Pinpoint pupils Reduced RR Drowsiness Cyanosis Coma ```

Question 40

What common feature of opiate OD can cause AKI?

Answer 40

Rhabdomyolysis

Question 41

What is the drug for opiate OD?

Answer 41

NALOXONE (opiate antagonist)

Question 42

how is naloxone given?

Answer 42

0.4mg at 2-3 minute intervals until the patient is rousable + resp distress is corrected

Question 43

Why are repeat injections of naloxone required?

Answer 43

It has a shorter half life than opioids (can be given as IV infusion)

Question 44

What problem may occur if giving naloxone to someone who is opiate-dependant? How would you manage this?

Answer 44

Could precipitate an acute withdrawal reaction (avoid giving enough to completely reverse opiate effects) Diazepam

Question 45

How may salicylate OD present? (ears!)

Answer 45

Tinitus

Question 46

If someone presents within 1 hour of salicylate OD, what can be given?

Answer 46

Charcoal

Question 47

What can be given in salicylate OD?

Answer 47

Sodium bicarb

Question 48

What is the treatment of choice in severe salicylate poisoning?

Answer 48

Haemodialysis

Question 49

What is the reversal agent for benzodiazepine (e.g. diazepam) OD?

Answer 49

Flumazenil

Question 50

Why shouldn't flumazenil be given if benzo OD is mixed with tricyclics?

Answer 50

Flumazenil lowers the seizure threshold

Question 51

What is the king's college criteria for liver transplant?

Answer 51

``` FOR PARACETAMOL OVERDOSE!! Arterial pH <7.3 after 24 hours OR all 3 of: PT >100 Creatinine >300 Encephalopathy ```