Toxicology Flashcards

(61 cards)

1
Q

When to NOT use charcoal

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Indications for multi dose activated charcoal

A

Massive modified release paracetamol
Carbamazapine
Phenobarbitone
Theophylline
Quinine
Dapsone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Indications for dialysis (apart from AEIOU)

A

Toxic alcohols
Salicylate
Theophylline
Lithium
Metformin
Potassium
Valproate
Carbamazapine
Phenobarbitone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

1 pill can kill in toddler

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Isopropanolol

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Sotalol OD

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Lithium
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
Arsenic
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
Lead
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
Mercury
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
Chelating agents
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
Paracetamol toxicity
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
Paracetamol levels and investigations
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
Acute single ingestion paracetamol within 8 hours
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
When to get advice with paracetamol toxicity
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
Delayed single ingestion paracetamol
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
Repeated ingestion paracetamol
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
Modified release paracetamol ingestion
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
How to do whole bowel irrigation and complications
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
How and when to give sodium bicarbonate
- 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
Amphetamines
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
Cocaine
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
Opioids
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
Body packers/stuffers
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
Carbon monoxide
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
Cyanide
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
Methaemoglobinaemia
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
Carbamazapine
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
Sodium valproate
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
Toxicological causes of delirium
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
Differentials of the hot and confused patient
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
Neuroleptic malignant syndrome
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
Serotonin syndrome
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
Anticholinergic syndrome
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
Cholinergic syndrome
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
Organophosphates
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
Hydrocarbons/terpines/essential oils
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
Paraquat
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
SSRIs (Citalopram, fluoxetine, sertraline)
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
SNRIs (venlafaxine)
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
TCAs (amitriptyline)
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
MAOIs
>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
Resus RSI DEAD
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