Toxicology Flashcards

1
Q

When to NOT use charcoal

A

Later than 2-4 hours
Risk of aspiration
Alcohols
Hydrocarbons
Metals
Corrosives

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2
Q

Indications for whole bowel irrigation

A

Iron > 60mg/kg
Slow release potassium > 2.5mmol/kg
Lead
Arsenic
Life threatening slow release verapamil/diltiazem
Body packers

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3
Q

Indications for multi dose activated charcoal

A

Massive modified release paracetamol
Carbamazapine
Phenobarbitone
Theophylline
Quinine
Dapsone

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4
Q

Indications for dialysis (apart from AEIOU)

A

Toxic alcohols
Salicylate
Theophylline
Lithium
Metformin
Potassium
Valproate
Carbamazapine
Phenobarbitone

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5
Q

1 pill can kill in toddler

A

Amphetamines
Diltiazem/verapamil
Chloroquine
Oxycodone, morphine, methadone
Propanolol
Sulfonylureas
Theophylline
TCAs

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6
Q

1 sip can kill in toddler

A

Organophosphates
Paraquat
Hydrocarbons
Toxic alcohols
Eucalyptus oil, camphor
Naphtholene
Caustic agents - ammonia, boric acid, hydrofluoric acid

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7
Q

Toxic causes of delirium

A

Alcohol intoxication/withdrawal
Serotonin syndrome
Neuroleptic malignant syndrome
Anticholinergic syndrome
Sympathomimetic syndrome
Benzodiazapines
Cannabis
Hallucinogenic agents
Salicylate OD
Theophylline OD
Atypical antipsychotics

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8
Q

Methanol - features and investigations

A

Home brew, paints, varnishes, dyes, carburettor fluid
Metabolised to formic acid
Ingestion > 0.5ml/kg fatal
Effects at 12-24 hours
- Headache, dizzy, blindness, cerebral oedema, permanent extrapyramidal disorders
High osmolar gap and HAGMA

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9
Q

Ethylene glycol - features and investigations

A

Antifreeze, radiator coolant, brake fluid, solvents
Metabolised to glycolic and oxalic acid
Ingestion > 1ml/kg fatal
Effects 4-12 hours
- SOB, tachycardia, HTN, seizures, coma, cranial nerve palsies, oxalate deposits in kidneys (RTA)
High osmolar gap and HAGMA
AKI and hypocalcaemia

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10
Q

Treatment methanol/ethylene glycol

A

Prevent metabolism
- 1.8ml/kg 43% vodka PO or 8ml/kg 10% ETOH IV
- infusion to maintain ETOH level 100
Manage acidosis
- 50mmol bicarb IV
- hyperventilate if ETT
Elimination
- Dialysis
Fomepizole is antidote, not available here

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11
Q

Isopropanolol

A

Surgical spirits - disinfectant, solvents, window cleaners
4ml/kg can cause coma
Supportive as per ETOH intoxication

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12
Q

Beta blocker OD features

A

Bradycardia and hypotension
Bronchospasm and pulmonary oedema - increased risk if elderly or asthmatic
Hypoglycaemia, hyperkalaemia
Altered mental state

ECG - bradycardia, conduction defects, AV block

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13
Q

Beta blocker OD treatment

A
  • Charcoal
  • Expect bradycardia and hypotension - IVF, atropine 0.6mg, isoprenaline 1-10mcg/min, adrenaline 1-10mcg/min (pacing rarely useful)
  • High dose insulin glucose 1unit/kg/hr up 10 10 with 10% dextrose 100ml/hr - titrate BSL 4-8, check every 30-60 mins, anticipate K replacement
  • glucagon rarely used
  • ECMO
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14
Q

Propanolol OD

A

Treat as TCA OD
Toxicity can start at 1g
CNS effects - seizures, coma
QRS widening - treat with bicarbonate 50-100meq (1-2meq/kg) repeated until normal QRS

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15
Q

Sotalol OD

A

Can cause prolonged QTc -> torsades
Isoprenaline +/- adrenaline
10mmol magnesium sulphate IV

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16
Q

Calcium channel blocker OD features

A

Most concerning are diltiazem and verapamil
2-3x normal dose (10 tabs, > 15ml/kg) toxic
Can be immediate release - first 2-4 hours or delayed 4-16 up to 24 hours
Bradycardia, 1-3 HB, hypotension, ACS, CVA, ischaemic gut, hyperglycaemia, lactic acidosis, shock, seizures

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17
Q

Calcium channel OD treatment

A
  • Charcoal (up to 4 hours slow release)
  • Expect bradycardia and hypotension - IVF, pacing (rather than drugs), adrenaline, ECMO/bypass
  • High dose insulin glucose therapy
    Calcium glutinate 10-20mls 10% IV repeated with monitoring of Ca levels
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18
Q

Acute digoxin OD features

A

Drugs, toad toxin, oleanders
10 x daily dose toxic, lethal > 10mg (4mg children)
GI early - n+v, abdo pain
CVS later 8-12 hours - bradycardia, slow AF, HB, increased automaticity, bigeminy, SVT, VT, hypotension
CNS - leathery, confusion, seizure

Dig levels at 4 hours
< 1 therapeutic
2-3.2 potentially toxic
> 3.2 toxic

Often hyperkalaemia - poor sign if > 5.5 early

ECG - reverse tick ST depression lateral leads, shortened QTc

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19
Q

Acute digoxin OD treatment

A
  • Cardiac arrest - 20 amps digibind
  • Life threatening arrhythmia, refractory hypotension, refractory hyperK, significantly symptomatic then give digibind
  • dose digibind vials = ingested dose in mgx0.8x2
  • if unknown start 2-5
  • atropine 0.6mg, pacing
  • arrhythmia - magnesium, lignocaine
  • hyperK - insulin/dextrose, bicarb NOT calcium
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20
Q

Chronic digoxin toxicity

A

Usually intercurrent illness (sepsis, NSAIDs etc) so renal impairment and delayed elimination
GI upset, bradycardia, syncope
Lower levels than acute cause problems
- bradycardia alone with level 2.5 50% toxic
- GI alone with level 2.5 60% toxic
- bradycardia and GI level 2.5 90%
- automaticity + others level 2.5 100%

  • cardiac arrest 5 amps
  • digibind 1-2 amps
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21
Q

Salicylate features and investigations

A

GI - n+v, mucosal erosion, GI bleed
Resp - tachypnoea, pulmonary oedema 10%
CNS - tinnitus 90%, tetany, confusion, seizures, coma
Other - sweating, hyperthermia, nephrotoxicity

< 150mg/kg OK
300mg/kg mild/mod
< 500mg/kg serious
> 500mg/kg potentially fatal

Salicylate levels to guide treatment, peak 12 hours
Hypokalaemia
Mild transaminitis
Resp alkalosis then metabolic acidosis
20% have hyperchloraemic NAGMA
Resp acidosis is sign of severity

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22
Q

Salicylate treatment

A

Activated charcoal
Maintain adequate hydration and high urine flow
Correct electrolytes
Alkalinisation urine if pH < 7.1
Haemodialysis if level > 9.4
ETT is high risk - pretreat with bicarb and hyperventilate pre/during/post

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23
Q

Opiods

A

Triad - miosis, resp depression, CNS depression
Aspiration, hypothermia, hypoxic brain injury, rhabdo

Pethidine - serotonin syndrome
Dextropropoxyphene - seizures

Naloxone 100-400mcg bolus
2 x boluses needed then start infusion at 2/3 initial dose required/hr and titrate

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24
Q

Iron

A

20-60mg/kg moderate, 60-90mg/kg requires decontamination, > 130 potentially fatal

Vomiting within 80 mins in 90%, direct GI irritation
Hypotension, acidosis, myocardial damage, inhibition coagulation, confusion, coma
0-3 hrs GI symptoms
12-48 hrs systemic symptoms
2 weeks strictures

Iron level at 4 hours
Hyperglycaemia, acute tubular necrosis, hepatoxicity, prolonged INR/APTT, elevated WCC, metabolic acidosis
CXR/AXR for FB

Resonium, gastric lavage, whole bowel irrigation, scope
Desferioxamine if coma, acidosis, peak level > 90. Can promote infection - stop if fever, give abs

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25
Q

Lithium

A

Narrow therapeutic index 0.8-1.2
Toxicity with intercurrent illness
Acute > 40mg/kg, symptoms over 3-5 days

< 1.5 Lethargy, fine tremor, memory deficits
< 2.5 confusion, visual disturbances, ataxia, coarse tremor, hyperactive reflexes
< 3.5 myoclonic twitches, nystagmus, stupor
> 3.5 seizure, flaccid paralysis, coma

T wave flattening or inversion, prolonged PR/QRS/QT
Hypokalaemia, abnormal TFTs

Gastric lavage
Diuresis with IVF
Dialysis
Supportive

26
Q

Arsenic

A

Acute - n+v, diarrhoea, hyper salivation, garlic odour, haematemesis, hyperthermia.
Subsequent hepatic/renal damage and encephalopathy
Bone marrow suppression 2-4 weeks
Painful peripheral neuropathy 1-3 weeks

Chronic - hair and nails, mees lines, desquamating rash, headache, confusion, seizures

24 hour urine arsenic level, X-ray, hair/nail clippings, prolonged QT

Whole bowel irrigation
Chelation - BAL, DMSA, Penicillamine

27
Q

Lead

A

Fumes, FB retention, contaminated drinks, improper storage foods in pewter, leaded glass, paint, batteries

Myalgia, hypo chromic microcytic anaemia, painless wrist drop, encephalopathy, HTN, gout, nephritis, abdo pain, infertility

Lead levels represent last 3-5 weeks
Children > 0.5 act on, symptomatic > 2.9

Chelation BAL or CaEDTA

28
Q

Mercury

A

Inorganic - batteries, vinyl, acetaldehyde, embalming, cosmetics
Ashen grey MM, metallic taste, stomatitis, abdo pain, poor muscle tone, red/oedmatous soles and palms, tachycardia, high/low BP

Organic - contaminated foods, paper/wood preservatives
Over days/weeks
Scotoma, ataxia, parasthesia, hearing loss, dysarthria, tremor, cognitive defects, paralysis

Mercury blood or urine levels
Xray

Decontamination
Can dialyse
Chelation - BAL, penicillamine

29
Q

Chelating agents

A

CaEDTA - lead, zinc

Penicillamine - copper, second line lead, iron, zinc, mercury, arsenic.
CI in pregnancy, renal disease, penicillin allergy

BAL - acute inorganic mercury, lead
CI in peanut allergy

DMSA - mercury, lead

30
Q

Paracetamol toxicity

A

Large ingestions mean P450 pathway needed to metabolise which produced NAPQI - hepatic, renal, cardiac, neuro toxic

Increased risk hepatoxicity:
- depletion glutathione - malnutrition, HIV, chronic hepatic
- induction P450 - ETOH, anticonvulsants etc

Toxic doses:
> 10g or > 200mg/kg
Very large > 50g or > 1000mg/kg or > 3 x above nomogram

Repeated:
> 12g or > 300mg/kg (>150mg/kg children) over single 48 hour period OR
> 4g or > 60mg/kg per 24 hour period for 48 hours with associated abdo pain/nausea/vomiting

31
Q

Paracetamol levels and investigations

A

Level taken at 4 hours
Nomogram validated to 16 but extrapolated to 24

Check baseline ALT in all

If massive or features hepatoxicity then full LFTs, coats, electrolytes (hypokalaemia common), blood gas (for metabolic acidosis), glucose (hypogylcaemia common)

32
Q

Acute single ingestion paracetamol within 8 hours

A

Charcoal if within 2 hours then NAC
200mg/kg IBW over 4 hours then
100mg/kg over 16 hours - if level is > 2 x nomogram then second bag is at double dose (so 200mg/kg over 16 hrs)

Check ALT 2 hours before stopping - if > 50 or rising then need to continue
Check paracetamol 2 hours before stopping only if initial level was > 2 x normogram - if > 66 then need to continue

If continuing then can only stop when:
ALT/AST decreasing
INR < 2
Patient clinically well

100% protection if started by 8 hours

Adverse effects - vomiting, fever, allergy - stop infusion, give antihistamine, restart at 1/2 rate for 30 mins then increase to normal rate

33
Q

When to get advice with paracetamol toxicity

A

IV paracetamol overdose
Very large overdose - > 50g or > 1g/kg or > 3 x nomogram level
Initial hepatotoxicity ALT > 1000

Liver unit:
INR > 4.5 anytime or > 3 at 48 hours
Oliguria or creat > 200
Acidosis pH < 7.3 despite treatment
Persistent hypoglycaemia
SBP < 80 despite resus
Severe thrombocytopenia
Encephalopathy
Survival < 10% without transplant

34
Q

Delayed single ingestion paracetamol

A

8-24 hours
Start NAC immediately
Check paracetamol and ALT levels

If under nomogram and ALT < 50 - no further treatment

If above line or > 50 then NAC as per protocol, recheck at 2 hours prior to stopping as per acute ingestion

> 24 hours
Start NAC and check levels
If paracetamol < 66 and ALT < 50 then stop
If either elevated continue as per acute ingestion

35
Q

Repeated ingestion paracetamol

A

Measure paracetamol and ALT
Start NAC if paracetamol > 120 or ALT > 50
Repeat at 8 hours
If paracetamol < 66 and ALT < 50/static can stop
If elevated then continue NAC and recheck levels every 12 hours - stop when meets criteria above

36
Q

Modified release paracetamol ingestion

A

If < 10g or 200mg/kg
- paracetamol level 4 hours post ingestion (start NAC if above line)
- further level 4 hours after this (start NAC if above line)
- if both below, d/c

If > 10g or 200mg/kg
- charcoal up to 4 hours and consider more than 1 dose
- start NAC and complete 20 hours regardless of initial paracetamol level
- check level and ALT 2 hours before stopping, stop if meets usual criteria

37
Q

How to do whole bowel irrigation and complications

A

CI - threatened airway, bowel perforation, bowel obstruction, GI haemorrhage

Adverse effects - aspiration, n+v, bloating, metabolic acidosis, delay/distraction from other resus/supportive measures, labour intensive

Give PO or NG 2L/hour (children 25ml/kg/hr)

38
Q

How and when to give sodium bicarbonate

A
  • Cardiotoxicity due sodium channel blockade (propranolol, TCAs, chloroquine, quinine, bupropion)
  • Urinary alkalisation (salicylates, phenobarbital)
  • profound acidosis (cyanide, toxic alcohol, isoniazid)

CI - APO, hypoK, severe hyperNa, renal failure

Adverse effects - alkalosis (keep pH < 7.6), hyper Na, hyper osmolarity, hypoK, local tissue irritation, fluid overload

2mmol/kg bolus initially
In cardiotoxicity can repeat 5 mins until stable
Infusion 100mmol in 1000mls at 250ml/hr guided by ABG and ECG

39
Q

Amphetamines

A

Acute - sympathomimetic symptoms 4-6 hours
Supportive, benzos, labetolol to control BP, B blockers for arrhythmia, cooling

Chronic - weight loss, poor dentition, cardiomyopathy, insomnia, paranoia, psychosis, social effects

Withdrawal in 85% lasting 3-5 days or up to weeks

40
Q

Cocaine

A

Acute - sympathomimetic symptoms
Myocardial ischaemia (50% thrombus, 50% vasospasm)
Prolonged QRS and QTc
HTN, ICH, seizures
Crack lung - fever and haemoptysis
Movement disorders

Chronic - Cardiomyopathy, myocarditis (IV), perforated nasal septum

Supportive
May need ACS treatment

41
Q

Opioids

A

Acute - triad CNS depression, resp depression, miosis
May be aspiration, hypothermia, rhabdo, compartment syndrome, hypoxic brain injury

Pethidine - serotonin syndrome
Dextropropxyphene - seizures

Naloxone 100-400mcg, repeat as needed, infusion if 2 x given (2/3 initial dose needed to reverse/hr and titrate)

Observe 4-12 hours depending on preparation

Withdrawal lasts 6hrs - 2 weeks - GI symptoms, lacrimation, salivation, anxiety, mydriasis, diaphoresis.
Admit if severe/complications/intercurrent illness. Give opiates or clonidine

42
Q

Body packers/stuffers

A

Packing - concealing drugs in planned way, large amounts so can be severe toxicity if leaks, bowel obstruction

Stuffing - last minute concealment, smaller package but badly wrapped

Plain films useful, CT if concerns
Stuffers - observe 8 hours
Packers - observe until passed and repeat imaging OK

43
Q

Carbon monoxide

A

Colourless and odourless
Cigarettes, car exhausts, heating malfunction
240 x affinity than O2 for Hb

Features correlate to end level CO exposure
Headache, vertigo, ataxia, visual disturbance, confusion, seizures, coma, n+v, arrhythmias, ischaemia, pulmonary oedema, cherry red skin

Long term neuropsychological symtoms (increased risk if pregnant, > 55, ischaemia, acidosis, significant LoC)

Ix - elevated CO level, metabolic acidosis, hyperglycaemia, rhabdo, renal injury

Rx - 100% O2 at least 8 hrs/until symptoms resolved (24hrs if pregnant)
Hyperbaric O2

44
Q

Cyanide

A

Fires, photographic/tanning/plastic industries, sodium nitroprusside, pips/seeds (almonds, peaches, apples etc)

Death rapid
Burning MM, SOB, vomiting, tachycardia, confusion, seizures, coma, CVS collapse, bitter almond odour, cherry red macula, miosis

HAGMA with elevated lactate
Gastric aspirate - litmus blue/green if cyanide
Cyanide levels often delayed

Rx - remove clothing, do not wash, 100% O2, hyperbaric O2, supportive
Hydroxycobalamin 5g
Sodium thiosulphate 50mls 25%
Produce methaemoglobinaemia (not if CO poisoning also present) with sodium nitrite or amyl nitrite

45
Q

Methaemoglobinaemia

A

Iron in oxidised form in Hb so not able to carry O2
Drugs - sulphurs, dapsone, chloroquine, nitroglycerin, prilocaine
Chemicals - nitrites, phenols, recluse spider bite
Infants < 6/12 - prematurity, dehydration, systemic acidosis, congenital

Symptomatic levels 20-50%, lethal > 70%

Cyanosis out of proportion to resp distress
SOB, tachycardia, hypotension, met acidosis, dizzy, seizures, coma

Methylene blue img/kg if severe

46
Q

Carbamazapine

A

Sodium channel blockade and antimuscarinic effects
Peak level 8-12hrs
Severe toxicity if > 160

Dizziness, confusion, ataxia, dystonic reactions, reduced GCS, seizures, tachycardia, QRS widening, long QTc, hypotension, CVS collapse

Multi dose activated charcoal
IV bicarb
Dialysis
Supportive

47
Q

Sodium valproate

A

GABA effects
Peak level 10 hours
> 400mg/kg severe

Lethargy, coma (if level > 850), tachycardia, hypotension
Thrombocytopenia, leucopenia, metabolic acidosis, hypernatraemia, hypoglycaemia, high ammonia

Charcoal
Supportive
Dialysis if severe or level > 4800

48
Q

Toxicological causes of delirium

A

Alcohol intoxication
Alcohol withdrawal
Serotonin syndrome - SSRIs, SNRIs, TCAs, lithium, tramadol, fentanyl, MDMA
Neuroleptic malignant syndrome - haloperidol, metoclopramide, prochlorperazine
Sympathamomietic syndrome - amphetamine, cocaine, theophylline
Anticholinergic syndrome - parkinson drugs, TCAs, antipsychotics, carbamazepine, oxybutynin
Cannabis
Hallucinogens
Salicylate OD
Theophylline OD
Atypical antipsychotic OD

49
Q

Differentials of the hot and confused patient

A

Meningoencephalitis
Systemic sepsis
Heat stroke
Anticholinergic syndrome
Serotonin syndrome
Neuroleptic malignant syndrome
Sympathomimetic syndrome
Alcohol withdrawal
Methylxanthine toxicity
Salicylate toxicity
Thyrotoxicosis
Phaeochromocytoma
Malignant hyperthermia

50
Q

Neuroleptic malignant syndrome

A

Haloperidol, chlorpromazine, prochlorperazine, metoclopramide etc
0.5-1.5% patient on neuroleptic drugs
Start, change, addition of drug increases risk
Young, male, dehydration, comorbid, organic brain disorder, genetic increases risk

Slow onset over days, weeks to resolve
CNS - confusion, stupor, coma
Autonomic - fever, tachycardia, labile BP, arrhythmias
Neuromuscular - lead pipe rigidity, bradykinesia, reduced reflexes, abnormal postures/movements, mutism, staring

Can have high WCC, AKI, deranged LFTs, NAGMA

Supportive, cooling, GTN for HTN, ETT
Bromocriptine - 2.5mg PO/NG Q8hr

51
Q

Serotonin syndrome

A

SSRIs, SNRIs, TCAs, MAOIs, lithium, amphetamines, tramadol, fentanyl
Start, change, addition, OD increases risk

More rapid onset over hours and resolve over 24hrs
CNS - delirium, apprehension, anxiety, seizure, coma
Autonomic - HTN, tachycardia, hyperthermia, sweating, mydriasis, flushing, diarrhoea
Neuromuscular - clonus (sustained, ocular/ankle), hyperreflexia, increased tone, rigidity, tremor
Hunter diagnostic criteria (clonus, agitation, sweating, tremor, hypertonia, hyperreflexia

Supportive
ETT if temp > 39.5
Hydration
Cyproheptadine mild/mod 8mg PO Q8hr

52
Q

Anticholinergic syndrome

A

Often other drug effects
Antiparkinson, antihistamine, TCAs, antipsychotics, carbamazepine, atropine, oxybutynin, orphenadrine, datura/mushrooms

Central - agitated delirium, picking, visual hallucinations, mumbling, slurred speech, fluctuating mental state, tremor, myoclonus, seizures, coma
Peripheral - tachycardia, dry mouth, dry skin, mydriasis, flushing, urinary retention, reduced bowel sounds, hyperthermia (blind as a bat…)

Supportive
Adequate hydration, IDC
Phyostigmine if not responding to benzos and isolated anticholinergic - 0.5-1mg IV

53
Q

Cholinergic syndrome

A

Acetylcholine agonists - acetylcholine, pilocarpine, nicotine, mushrooms
Acetylcholinesterase inhibitors - oraganophosphates, carbamates, chemical warfare, donepezil, neostigmine

CNS - agitation, seizures, coma
Muscarinic (DUMBBELLS) - diarrhoea, diaphoresis, urinartion, miosis, bronchospasm, bonchorrhoea, emesis, lacrimation, lethargy, salivation
Nicotinic - HTN, tachycardia, resp muscle weakness, fasiculations
Killer B’s - bronchospasm, bronchorrhea, bradycardia, breathing bad (resp muscle paralysis)

Early ETT (resp muscle weakness, secretions, coma)
Hydration (lots of secretions)
Atropine 1.2g IV 2-3 mins doubling dose then infusion to stop bronchospasm/bronchorrhea and bradycardia
Pralidoxime in organphosphate

54
Q

Organophosphates

A

Inhibit acetylcholinesterase
Can bind irreversibly in ageing (not carbamates)

Inhalation - usually within 5 mins
Transdermal/oral - several hours
Cholinergic signs (DUMBBELLS etc), pulmonary oedema in 40%, garlic smell
Delayed muscle weakness after resolution initial cholinergic signs 24-96hrs in 10-40% (resp muscles, cranial nerves, pros limb flexors)
Polyneuropathy at 2-3 weeks - rare

ST elevation, QTc prolongation, arrhythmias common
RBC acetylcholinesterase or plasma pseudocholinesterase - often delayed

PPE - universal precautions, remove clothing, soap and water
Atropine 1.2mg IV Q5mins doubling dose until chest clear, secretions, dried, HR acceptable
Pralidoxime - must be given early

55
Q

Hydrocarbons/terpines/essential oils

A

Petrol, diesel, kerosene, turps, toluene, camphor

CNS - ataxia, euphoria, seizures, coma, myopathy, cerebellar dysfunction, encephalopathy
CVS - in severe - arrhythmias, hypotension
GIT - d+v, haematemesis
Pulmonary - aspiration, oedema
Bone marrow suppression
Metabolic acidosis

Supportive, dialysis

56
Q

Paraquat

A

Most lethal poison, small sip can kill

Early - GI /corrosive injury
Multiorgan failure around 48 hours
If survive > 48 hours get pulmonary fibrosis

Serum level >5 fatal, >2.5 90% fatal
Extensive bloods to assess organ damage

PPE
Immediate decontamination, remove clothes, fullers earth/charcoal
Dialysis
O2 only is sats < 90 and aim no more than 92%
Consider palliation

57
Q

SSRIs (Citalopram, fluoxetine, sertraline)

A

Onset 4 hours, offset 12 hours
Es/citalopram worse - more associated with seizure (2-10%, short), dose dependent QTc prolongation when >500mg - rarely tornadoes
Risk - >500mg citalopram, >1200mg fluoxetine

Tremor, anxiety, mydriasis, nausea, drowsy, tachycardia
Serotonin syndrome if coningestants, severe

Supportive
Early ETT if temp >39.5
Adequate hydration
Cyproheptadine 8mg PO TDS if mild/mod

58
Q

SNRIs (venlafaxine)

A

Delayed 6-12 hours, 16 hours observation

Anxiety, sweating, mydriasis, tachycardia, HTN, features serotonin toxicity
Seizure risk dose dependent >4.5g close to 100%
CVS effects if >8g - hypotension, QRS prolongation, QTc prolongation

Supportive
Bicarb if prolonged QRS

59
Q

TCAs (amitriptyline)

A

Effects at NA, serotonin, GABA, alpha, histamine and sodium channels
>10mg/kg severe

Rapid onset 1-2 hours
CNS - agitation, confusion, twitching, jerking, bladder/bowel paralysis, seizures, coma
Anticholinergic - mydriasis, myoclonic jerks, tachycardia
CVS - hypotension, prolonged PR/QRS/QTc, terminal R wave in aVR
QRS >100-20 predictive seizures, >160 predictive VT

Anticipate hypotension - fluids
Bicarb in refractory hypotension fixes 90%
Bicarb for prolonged QRS
Lignocaine next line
Early ETT

60
Q

MAOIs

A

> 2mg/kg serious toxicity
Can be delayed up to 24 hours

Serotonin and sympathomimetic symptoms esp if coningestants

Tyramine reaction if eat certain foods - occipital headache, HTN crisis, agitation, sweating

Supportive
HTN - GTN or labetolol

61
Q

Resus RSI DEAD

A

ABC, seizures, glucose, temp
Risk assessment - drug, dose, time, current clinical status (does picture fit), patient factors (comorbidities, weight)
Supportive care (fast hugs in bed please - fluids, analgesia/antiemetics, sedation, thromboprophylaxis, head up, ulcer prophylaxis, glucose control, skin/eye care, IDC, NGT, bowel care, environment, de-escalation, psychosocial support)
Investigations (ECG, paracetamol, others)
Decontamination - charcoal, while bowel, endoscopy
Enhanced elimination - multi dose activated charcoal, urinary alkalinisation, dialysis
Antidotes
Disposition