1. Dr Chris Cresswell
FACEM
Whanganui
New Zealand

2. The Bible
 TOXINZ.com

3. General approach
Resuscitate if needed
Risk assessment – is what they have taken dangerous?
Supportive Care and Monitoring
 depending on your risk assessment
Investigations
 Everyone:
 Paracetamol level
 ECG
 Other as indicated
Decontamination – very rare
Antidotes
Enhanced elimination - rare
Seek and treat complications
Disposition – usually psych. Psych does the psych risk assessment for
us.

4. Toxinology
Critters rather than drugs/chemicals
We have one rare annoying, non-life threatening
spider in NZ.
Katipo = red back – painful bite and sweating +/-
back pain -> analgesia + antivenom.
Controversial whether antivenom actually works.

5. Toxicology
Drugs and chemicals
Not going to cover them all!

6. Toxidrome
What’s a toxidrome?
What are some examples?

7. Toxidrome
Clinical toxicological syndrome
ie you can examine a patient +/- look at their ECG or
other bedside tests and get a good idea of what they
have taken
Eg
Opioid
Anticholinergic
Cholinergic syndrome
Serotonin syndrome
Na channel blockade

8. Toxidromes
Opioid: resp depression, decr LOC, miosis
Anticholinergic: hot as a hare, mad as a hatter, red as a beet,
dry as a bone eg datura
Cholinergic syndrome eg organophosphate, nerve gas
 SLUDGEM: salivation, lacrimation, urinarination,
diarrhoea, GI upset, emesis, miosis + muscle spasm
 Or DUMBELLS: diarrhoea, urination, miosis/muscle
weakness, bronchorrhoea/bradycardia, emesis,
lacrimation, salivation/sweating
Serotonin syndrome eg SSRI: sweating, agitation, increase
muscle tone, fever
Na channel blockade eg tricyclic: hypotension, decr LOC,
widened QRS
Rapidly alternating apnoea and coma eg GHB

9. Tox exam
HR
RR
Pupil size and reactivity and look for nystagmus
Armpits for sweat
Reflexes and test for clonus
Temp
ECG
BSL
Labs: almost everyone gets a paracetamol level
 Cheap test. Treatment very efficacious.

10. Some specific drugs / chemicals
Common or important ones.

11. Paracetamol/acetominphen
NB different units from UK
Common
Almost always reversible with antidote
High survival even from liver failure
How to you risk stratify and treat these ingestions?
What is the antidote?

12. Paracetamol/Acetominophen
 Most common scenario: single ingestion, reasonable idea of time.
 < 10g or 200mg/kg ingested within 8 hours does not need investigation
 Otherwise or unknown:
 < 2 hours post ingestion of non-liquid and cooperative patient ->
single dose activated charcoal.
 < 4 hours post ingestion: wait and take blood for paracetamol level at
4 hours post ingestion. N-acetylcysteine (NAC) if over 1000µmol/L.
 4-8 hours. Take level. NAC if over threshold on nomogram.
 8-24 hours. Take level and start NAC. Stop treatment if under
treatment threshold.
 24+ hours or unknown. Take level, VBG, LFT, glucose, INR, renal
function. Start NAC. Stop NAC if ALT normal. If liver failure d/w
liver unit

13. Paracetamol

15. Multiple doses
Look it up

16. NAC
N-acetylcysteine
Very safe and effective
Boxes in ED with dose schedule written on them
3 different rates over 24 hours
Fairly frequent anaphylactoid reaction
Eg erythema, urticaria, pruritis, hypotension
Thought to be from histamine release rather than true
anaphylaxis
If mild reaction half rate +/- give IV antihistamine
If severe reaction. Stop infusion. Give IV antihistamine +/-
bronchodilators, fluids etc. Once asymptomatic for 1 hour
restart infusion at ¼ rate and titrate up

17. Disposition
In this hospital all patients requiring NAC get
admitted to ward under medical team.
Inform psych of admission. They say they will see
patient before “medically cleared”

18. SSRIs
What do you need to know about these?

19. SSRIs
Usually no significant toxicity
Main risk is serotonin syndrome
What is serotonin sydrome?

20. Serotonin Syndrome
Rare
Excess serotonin usually from over dose of SSRI or
combination of serotonergic agents
Eg
SSRI, St John’s wort
Antipsychotics
Lithium
Pethidine
Tramadol
LSD
Ecstacy and other amphetamines

21. Serotonin Syndrome
Serotonergic drug +
Mild: Tremor, anxiety, nausea
Moderate: agitation and hyperreflexia and clonus
Severe: severe: fever, seizures, respiratory failure,
rhabdomyolysis, renal failure, DIC

22. Serotonin syndrome
Management
Mild: observe for 4-6 hours
Moderate: IV fluids, benzodiazepine, +/-
cyproheptadine
Severe: cooling, IV benzodiazepine, IV fluid. May need
RSI

23. So for all overdoses of serotonergic
agent need ...
Record
Temperature
Tone
Reflexes
Clonus

24. CCB and Beta Blocker
Cause ?

25. CCB or Beta Blocker
Hypotension and bradycardia
Most beta blockers fairly benign
Exception: propranolol: Na channel blocking effect:
manage as for tricyclic + Beta blocker
Calcium channel blockers: nasty
Treatment?

26. Beta blocker + CCB
Resuscitate if required: ABCs
Risk assessment: look up to see how toxic the dose could be.
Supportive care and monitoring: if moderate risk: resus bay, IV
access, cardiac monitoring, IV fluids, trial of atropine, calcium
gluconate, pressors eg dopamine. If high risk likely to need
intubation
Investigations: ECG, paracetamol level, lactate, glucose.
Decontamination: Whole bowel irrigation likely to be needed
eg Polyethylene glycol via NG tube

27. Beta blocker + CCB
Antidote/specific treatments: could call calcium an
antidote to CCB, glucagon 5mg IV, high dose insulin 1
unit/kg then 1unit/kg/hour
Enhanced elimination: dialysis ineffective. Multidose
activated charcoal may be effective for CCB.
Seek and treat complications: Likely to need ICU
care. Monitor for MOF, rhabdo etc

28. If all of the above wasn’t working what else could be
done?

29. Intraarterial balloon pump
Bypass/ECMO
Most life threatening drug ingestions cause
temporary CVS collapse – if we can support them
through this the patient should do well

30. Sulphonylureas
Life threatening
Antidote?

31. Sulphonylureas
Antidote: IV glucose then IV octreotide

32. Iron
What’s important about iron
What’s the antidote

33. Iron
Can be life threatening and yet the patient is
asymptomatic, or has recovered
Look it up
Most accidental ingestions not harmful
Over a threshold ingestion -> iron levels useful
Low threshold for whole bowel irrigation
Antidote: desferoxamine

34. Digoxin
What are the 2 main types of toxicity?
What are the classic signs and symptoms?
What is the antidote?

35. Digoxin
2 main types of toxicity:
 Acute ingestion – rare
 Chronic – usually due to dehydration/renal impairment
 Consider this in any patient on digoxin who is unwell. Check ECG, K+ and
digoxin level
Classic signs and symptoms
 Yellowed vision
 Nausea and vomiting
 Confusion
 Cardiac automaticity (ectopics or tachyarrythmia) and block
What is the antidote?
 Digoxin FAB fragments – “digibind”
 Expensive but cost effective

36. Indications for Digoxin FAB
Hemodynamically unstable or life-threatening
dysrhythmia,
Hyperkalemia > 6 mmol/L (6 mEq/L)
Plasma digoxin level > 20 nmol/L (15.6 ng/mL) at 6
hours post-ingestion
Digoxin level > 10 nmol/L (7.8 ng/mL) or elevated
digoxin level + renal impairment + symptoms in
chronic toxicity

37. Local anaesthetic
Eg femoral nerve block -> intraarterial
Classic signs?

38. Local anaesthetic
Perioral tingling
Others:
Visual disturbance
Seizure
VT
Antidote?

39. Local anaesthetic
Intralipid
? Lipid sink
? Cardiac fuel

40. Tricyclic / propranalol
Na channel blockade
Nasty
Hypotension
Decr LOC
Seizure
Dysrhythmias
Antidote?

41. Na channel blockade
"Prompt intubation, hyperventilation and
administration of administration of sodium
bicarbonate at the first evidence of severe toxicity is
life-saving"

42. Na channel blockade from TCA

43. Blue apnoeic patient dumped at the front door.
He has pin point pupils
How will you manage this patient?

44. IV opioid toxicity
Lots of techniques
BVM ventilate
400mcg IM naloxone
200mcg IN naloxone

45. Oral opioid toxicity
If significant respiratory/LOC depression usually
require naloxone infusion
Titrate IV nalaxone boluses to get just adequate
reversal – don’t make the patient withdraw and run
Infusion of 2/3 of reversal dose/hour

46. Rare but nasty
Theophylline -> vomiting +++ -> needs urgent
dialysis
Ethylene glycol

47. Neuroleptic Malignant Syndrome
What is it?
What do you do about it?

48. Neuroleptic malignant syndrome
Rare
Usually an idiosyncratic reaction to standard/high
doses of antispychotic rather than a result of
overdosage.
Life threatening
“Malignant Parkinson’s”
Parkinsonism + fever + autonomic instability
Doesn’t have the agitation, hyperreflexia or clonus of
serotonin syndrome

49. Neuroleptic malignant syndrome
If temp > 39.5 or rigidity compromising ventilation ->
RSI
Cool to 38-39˚
Benzodiazepines
Treat hypoglycaemia
Bromocriptine +/or dantrolene

50. “My child might have taken some of granny’s
pills”
Try to work out what Granny is on
Default
Blood sugar
BP
ECG
If abnormal or toxidrome: IV line and treat empirically.
If normal: Observe 12 hours. Discharge if BP and BSL
normal

51. Benzodiazepines
Antidote – when do we use it?

52. Flumazenil
Antidote to benzos
Almost never used
Only used if we caused the OD
For chronic benzo users or coingestion with a
proconvulsant (eg TCA) flumazenil may cause seizure
Benzos almost never need treatment or intubation
Recovery position, wait for them to wake up

53. Alcohol
Almost never needs intubation
Recovery position and observe
LOC should improve hourly – if not consider other
diagnosis eg head injury

54. Activated charcoal
Almost never used
Little proof of efficacy
Has killed people - aspiration

55. Hydrofluoric acid
Nasty. 2% BSA exposure can kill

56. Warfarin
Vitamin K and prothrombin complex
(prothrombinex)

58. Insulin
Glucose + food
Occasionally 10% glucose infusion

59. CO and cyanide
High flow oxygen then look it up
Cyanide ? Amyl nitrate, Sodium nitrite, sodium
thiosulphate (or dicobalt EDTA where available)

60. Questions?
Comments?
Suggestions?
chris.cresswell@wdhb.org.nz