ACUTE POISONING

1
ACUTE POISONING

• Major C J Porter RAMC
• Army Medical Directorate
• Emergency Medicine Registrar
• Bristol Royal Infirmary

2
Outline of lecture

• Epidemiology
• Toxidromes
• History, examination and detective work
• General management
• Specific management
• Antidotes
• Scenarios

3
EPIDEMIOLOGY

• 4000 UK deaths per year (1/3 CO)
• Most deaths outside hospital
• 100,000 Hospital admissions (12)
• Not just overdoses Illicit drugs, Alcohol

4
EPIDEMIOLOGY

• Self poisoning
• FgtM
• 1/3 gtone drug
• Taken with alcohol F 40 M 60
• Repeated self-poisoning 11 of admissions

5
SUICIDE

• 2 of male deaths
• 1 of female deaths
• Method
• Female Poisoning 40
• Male Gas / Hanging / Suffocation
• Self-harm parasuicide
• 1 dead after 12 months
• 3-5 dead after 5-10 years

6
Toxidromes

• Patterns of signs and symptoms
• Useful to help in diagnosis and treatment of
  unknown poisons

7
Opiates

• Respiratory depression
• Cardiovascular depression
• Reduced level consciousness
• Pinpoint pupils
• Pulmonary oedema
• Hypothermia
• (Rapid response to Naloxone)

8
Common causes

• Opiates heroin, morphine etc

9
Sympathomimetics / Stimulants

• Agitation/delusions/paranoia
• Fight/Flight response
• Tachycardia
• Hypertension
• Arrhythmias
• Dilated pupils
• Seizures
• Hyperpyrexia

10
Common causes

• Cocaine
• Amphetamines
• Decongestants
• Ecstasy

11
Anticholinergic

• Tachycardia
• Arrhythmias
• Pupils mid-point or dilated / divergent
• Confusion / drowsiness / coma
• Seizures
• Dry flushed skin
• Urine retention
• Hypertonia, Hyper-reflexia, Myotonic jerks

12
Anticholinergic signs

• Hot as a hare
• Blind as a bat
• Dry as a bone
• Red as a beet
• Mad as a hatter

13
Common causes

• Antidepressants-Tricyclics
• Antihistamines
• Atropine
• Antipsychotics
• Antispasmodics

14
Serotonin Syndrome

• Similar to anticholinergic syndrome
• loss of consciousness uncommon
• sweating and tremor common
• Agitation
• Delirium
• Hypertonia / myoclonus
• Tachycardia
• Tachypnoea

15
Common Causes

• SSRIs
• MAOIs (Hyperpyrexia / Hypertensive crisis)

16
Cholinergic

• Brady/tachycardia
• Confusion/reduced GCS
• Pinpoint pupils
• Seizures
• Weakness
• SLUDGE
• Pulmonary oedema

17
SLUDGE

• S sweating salivation
• L lacrymation
• U urinary frequency urgency
• D diarrhoea
• G gastrointestinal discomfort
• E eyes pinpoint

18
(No Transcript)
19
Common causes

• Organophosphates
• Physostigmine
• Some mushrooms
• Nerve agents

20
Salicylism Aspirin

• Impaired hearing
• Tinnitus
• Sweating
• Warm skin
• Hyperventilation
• Cinchonism Quinine (salicylism blindness)

21
MANAGEMENT
22
Management Overview

• History assessment of vital signs
• ANY concerns move patient to RESUS
• A B C D
• DEFG
• Supportive care (O2, IV Fluids)
• Prevent absorption
• Increase elimination
• Antidotes
• PSYCHOLOGICAL ASSESSMENT

23
History

• What?
• When?
• How much? (mg/kg)
• What else?
• Why?

24
Collateral history

• Paramedics
• Family / friends
• Notes
• Look in pockets carefully!!!

25
(No Transcript)
26
Detective work

• BNF
• Toxbase
• Tablet identification aids TICTAC
• Poisons advice NPIS
• Plant identification books
• National teratology information service

27
(No Transcript)
28
(No Transcript)
29
Initial examination

• Treat problems as you find them!!
• Airway
• Breathing
• Circulation
• Disability GCS/AVPU and Pupils
• DONT EVER FORGET GLUCOSE

30
Observations

• Saturations and respiratory rate
• Pulse and blood pressure
• GCS
• Pupils
• Temperature
• GLUCOSE

31
Investigations

• All Patients
• Glucose
• UE
• Paracetamol Salicylate
• As indicated
• LFT
• Co-ag / INR
• CK
• ABG / VBG
• ECG
• CXR
• Urine toxicology screen

32
Reduce absorption

• Emesis No role
• Activated charcoal within 1 hour
• Gastric lavage rarely
• Whole bowel irrigation - rarely

33
Increase elimination

• Urinary alkalinisation
• Multi-dose Activated Charcoal
• Haemodialysis
• Haemoperfusion
• Plasma exchange
• Forced alkaline diuresis (no longer recommended)

34
Paracetamol

• Very common 40 poisons admissions
• Often asymptomatic
• Can be lethal 200-300 deaths/year
• Check blood level at 4 hours
• Two treatment lines normal and high risk
• Given IV N-acetylcysteine

35
Paracetamol metabolism

• Metabolised by glucuronidation (60),
• Sulphation (35) and oxidation (10)
• Cytochrome p450 produces NAPQI
• NAPQI toxic causes hepatocellular necrosis
  irreversible binding
• NAPQI detoxified by conjugation with glutathione

36
Prescott Nomogram
37
High Risk

• Increased oxidation
• Chronic alcohol use
• Drugs
• Reduces glutathione stores
• Malnutrition
• Eating disorders
• Chronic liver disease

38
N-acetylcysteine

• Most effective within 8 hours
• Precursor for glutathione production
• Can cause anaphylactoid reactions
• Consider starting before paracetamol result if
• Presenting gt 8 hrs gt150mg/kg taken
• Staggered overdose

39
To treat or not to treat?
40
Patient 1

• 20 year old woman who takes a handful of
  paracetamol tablets
• No drug history
• No alcohol use
• Fit and well
• Blood level is 80mg/l

41
No need to treat

• Patient is not high risk
• Level at 4 hours is below even the high risk line

42
Patient 2

• 70 year old man
• Takes 20 paracetamol 6 hours before presenting
• Alcoholic
• No drug history
• Blood level 100mg/l

43
Treat

• Patient is high risk
• Level is above the high risk line
• Delayed presentation means need to act fast

44
Patient 3

• 17 year old epileptic
• 25 codydramol 2 hours before attendance
• Taking carbamazepine
• Blood level at 4 hours is 120mg/l

45
Treat

• High risk patient
• Level above the high risk line

46
Patient 4

• 35 year old man who presents after taking 24
  paracetamol over a period of 24 hours
• No drug history
• Fit and well
• Blood level 20mg/l

47
Treat

• Staggered overdoses are difficult
• Poisons advice is to give IV acetylcysteine
• Levels are not that helpful
• Need to monitor Liver function, clotting and
  renal function
• May need discussing with Liver Unit if abnormal

48
PARACETAMOL

• DEADLY PITFALLS
• The Prescott Nomogram High Risk Line
• Staggered Overdoses
• Management of late presentation
• Recheck UE, LFT, INR after N-acetylcysteine

49
Tricyclics

• Antidepressants
• Dangerous US 60-70 fatal ODs
• UK commonest fatal OD per prescription
• 10 unconscious patient will fit
• Treat fits with diazepam/lorazepam

50
Tricyclic effects

• Anticholinergic toxidrome
• The 3 Cs
• Coma
• Convulsion
• Cardiac

51
Tricyclics cardiac effects

• Quinidine effects lead to arrhythmias
• ECG
• Sinus tachycardia
• Broad QRS RBBB
• Prolonged QT interval
• Right axis deviation
• Severe poisoning VT, bradycardia, heart block
• QRS gt 160mS ??risk of seizures and cardiac
  toxicity

52
Tricyclics

• ABG
• Hypoxaemia
• Metabolic acidosis
• Respiratory acidosis

53
Tricyclics

• Management
• EARLY ITU REFERRAL
• SODIUM BICARBONATE
• If hypotension resistant to fluid challenge
• Dysrhythmias
• Convulsions
• Consider IV Magnesium for resistant dysrhythmia

54
Salicylate

• Salicylism
• Dehydration
• Confusion /coma
• Seizures
• Haemetemesis
• Hypoglycaemia

55
Salicylate

• Metabolic and acid-base disturbance
• Complex
• Respiratory alkalosis direct stimulation to
  over breathe
• Metabolic acidosis- acid, impaired normal
  metabolism, production of lactic acid
• Check ABG / VBG

56
Salicylate

• Severity of ingested dose
• gt150 mg/kg mild
• gt250 mg/kg moderate
• gt500 mg/kg severe

57
Salicylate management

• Tailor treatment to symptoms
• Fluids
• Reduce absorption
• Activated charcoal
• Gastric lavage (gt500 mg/kg and lt1 hour)
• Increase elimination
• Urinary alkalinisation
• Cooling
• Glucose if hypoglycaemic

58
Salicylate management

• lt350mg/L oral fluids
• gt350mg/L urinary alkalinisation
• gt700mg/L haemodialysis
• DISCUSS WITH NPIS

59
Salicylate

• DEADLY PITFALL
• Salicylate levels can continue to rise following
  admission (10 of cases)
• Repeat levels every until peaked

60
Opiates

• Common
• Act on µ-receptors
• Reversible with Naloxone
• Naloxone pure opioid antagonist
• Naloxone
• Short half life may need repeated doses
• Give IV /- IM may need IVI

61
Antidotes

• Opiates naloxone
• Paracetamol acetylcysteine/methionine
• Beta-blockers glucagon
• Insulin glucose
• Iron desferrioxamine
• Carbon monoxide oxygen
• Methanol - ethanol
• (Benzodiazepines flumazenil)

62
(No Transcript)
63
Scenario 1

• 20 year old IVDU found by ambulance crew
  unconscious
• Needle lying by side
• Resp rate 6, Sats 94 on air
• 60bpm BP 100/55
• Responds to pain

64
What next?

• A Give naloxone
• B Check airway
• C Take history
• D Give flumazenil

65
Check airway

• Check airway patent
• Give oxygen
• Call for senior help
• Check glucose
• Give naloxone IM and IV

66
Scenario 2

• 30 year old woman
• Taken some white tablets 4 hours earlier
• Feels completely well
• Felt depressed after argument with partner
• Usually fit and well

67
(No Transcript)
68
What next?

• A Start N-Acetylcysteine
• B Discharge as she is obviously well
• C Find out what the tablets are
• D Take blood for paracetamol levels

69
Take bloods

• Early treatment is essential in paracetamol
  overdose
• Need to know what her levels are as soon as
  possible

70
(No Transcript)
71
Scenario 3

• 45 year old man works in local aquarium
• Put right hand into tank and got stung by a lion
  fish
• Respiratory rate 16 sats 100 on air
• Pulse 100 bpm 160/80
• Fully conscious
• Extreme pain in hand

72
Lion fish
73
What next?

• A Panic you know nothing about lion fish!
• B Look on Toxbase
• C Ring local zoo
• D Ask a senior who also knows nothing about
  Lion fish!

74
Toxbase

• Patient needs cardiovascular monitoring
• Analgesia
• Hand in water as hot as can tolerate
• Lion fish toxin is heat labile
• Carefully remove spines if present
• Few hours later patient feels much better goes
  home

75
Summary

• Common
• Approach using
• A B C D
• DEFG
• Consider the toxidromes
• Early senior help / Early ITU referral
• Supportive Care
• Antidotes
• Psychological assessment

76
Questions

• ?