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POISONINGS IN PAEDIATRICS

Poisonings in Paediatrics

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Poisonings in Paediatrics

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Page 1: Poisonings in Paediatrics

POISONINGS IN PAEDIATRICS

Page 2: Poisonings in Paediatrics

Definitons Poisoning: Exposure to a chemical or other agents that adversely affects functioning of an organ

Poison: A poison is any agent of self injury absorbed into the body through epithelial surfaces.

Toxin : Toxin are poisons produced by a natural biological process.

Venom : Venoms are toxins that are injected by a bite or sting to cause their effect.

Page 3: Poisonings in Paediatrics

Incidences:Poisoning represents one of the most common medical emergencies.Circumstances of Exposure can be unintentional,intentional, accidental, environmental, or medicinal.Total hospital admissions 0.33%-7.6%Unintentional exposure 80%-90% in infants to preschool children.Intentional exposure higher in older children and adolescents.

Developing countries ingestion of pesticides and plants.

Developed countries pharmceuticals and chemicals.

Children under 5 years are at higher risk.

Page 4: Poisonings in Paediatrics

Incidences: Of total poison cases., 50% cases occur in children <6yrs.

All are unintentional exposures to toxic substances.

90% toxic exposure home

Major ingestion route

Minor dermal, inhalational, ophthalmic routes

50% cases non-drug causes like cosmetics, plants, foreign bodies, etc.

Pharmaceutical products remains the cause for rest of the exposures.

Vit. C is most commonly reported drug exposure.

Page 5: Poisonings in Paediatrics

Incidences:

Only 6% of children's are affected in 6-12yrs of age.

Adolescents intentional exposure (suicide, abuse or misuse of substances)

These intentional exposures leads to severe toxicity stages.

Non toxic & minimal toxic chalk, crayons, ball point ink, ant-acids (except salicylates),etc.

Toxic B-blockers, CCB, camphor, Anti-malarial drugs, etc.

Recently, Carbon monoxide gas, CVS drugs, Anti-depressants, Anti-Psychotics Leading

Page 6: Poisonings in Paediatrics

Toxidromes:

It is the association of several clinically recognizable features, signs, symptoms, phenomena or characteristics which often occur together.

Clinical significant in single drug exposure.

Page 7: Poisonings in Paediatrics

Toxins Toxidromes

Sympathomimetic Hypertension, Tachycardia, Delirium, Dilated pupils, Diaphoretic skin,

Anticholinergic Hypertension , Tachycardia, Hyperthermia, Delirium, Mumbling Speech, Dilated pupils, Dry skin

Cholinergic Bradycardia, Confusion, coma, Fasciculation, Small Pupil, Diaphoretic skin

Opioids Respiratory depression, Bradycardia, Hypotension, Depression, Coma, Pinpoint Pupil, Normal Skin

Sedative- Hypnotics Respiratory depression, Coma, Small pupil, Normal Skin

Serotonin syndrome Hyperthermia, Tachycardia, Hypertension, Hypotension, Agitation, Confusion, Coma, Dilated pupil, Diaphoretic skin

Salicylates Tachypnea, Hyperpnea, Tachycardia, Hyperthermia, Agitation, Confusion, Coma, Normal pupil, Diaphoretic skin

Withdrawal Tachycardia, tachypnea, Hyperthermia, Lethargy, confusion, Delirium, Dilated pupils, Diaphoretic skin

Page 8: Poisonings in Paediatrics

Analgesics Acetaminophen Salicylates Ibuprofen & other NSAIDS Oral opioids

CVS drugsB-Adrenergic

receptor blockers

CCB Clonidine Digoxin

Iron

Oral hypoglycemics

Compounds:

Page 9: Poisonings in Paediatrics

Psychiatric medications

• Anti-depressants

• SSRI• Atypical Anti-

depressants• MOI• Anti-

psychotics

House hold products

• Caustics• Cholinesterace

inhibitor insecticides

Hydrocarbons

• Kerosene• Tar• Turpentine

Toxic alcohol

• Methanol• Ethylene

glycol

Compounds:

Page 10: Poisonings in Paediatrics

Acetaminophen (ACT) poisoning:Pathophysiology

N-acetyl-p-benzoquinone (NAPQI)

Cytochrome P450 enzyme

Glutathione

Non-toxic mercaptopuric acid

OverdosesGlutathione stores

overwhelmed

Free NAPQI combine with hepatic macromolecules

Induces hepatic damage

Page 11: Poisonings in Paediatrics

Dosages:Acute toxic dose:

Children >200mg/kg

Adolescents 7.5 – 10g

Doses >75mg/kg/day for consecutive days hepatic failure

Stages of acteminophen toxicity: Stage 1,2,3,4

Page 12: Poisonings in Paediatrics

Assessment:S.Acetaminophen levels 4hrs after ingestion.

Others Heaptic transaminases, RFT, Coagulation parameters.

Runmack- Matthew nomogram plot of S.acetaminophen levels vs time

Used within 24hrs of exposure with known ingestion time.

NAC is used, if in hepatotoxic range

Any other drugs combined 2nd S.ACT are taken in 6-8hrs .

Unknown cases S.ACT, Hepatic Trans., coagulation parameters

NAC normal LVT with ,10ug/ml & signs of hepatotoxcity with low or non-detectable ACT.

Page 13: Poisonings in Paediatrics

Treatment: 1-2hrs decontamination with activated charcoal

Antidote – NAC (N-acetyl cysteine)

-- restores glutathione stores

PO : 140mg/kg loading,

70mg/kg q4h *17doses

IV : 150mg/kg over 1hr,

followed by 50mg/kg over 4hr,

followed by 100mg/kg over 16hrs (mostly preffered)

Hypersensitivity IgE diphenhydramine, epinephrine, albuterol

Non responsive liver transplantation done based on King’s college criteria.

Page 14: Poisonings in Paediatrics

Hydrocarbons poisoning:Even smaller doses causes life threatening toxicity.

Classes of hydrocarbons Aliphatic / straight chain : acetone, butane, propane, isopropane Aromatic/ cyclic structures: benzene, toluene, xylene Toxic/ Halogenated : Carbon tetrachloride, trichloro ethylene Petroleum distillates: Kerosene, gasoline, furniture polish

Saybolt Universal Seconds (SUS) – aspirational potential of a hydrocarbon

Page 15: Poisonings in Paediatrics

Hydrocarbons poisoning:The propensity of hydrocarbon is inversely proportional to its viscosity

Compounds with low viscosity spread rapid affect large areas when aspirated

<1mL produce significant injury

Gasoline & kerosene poorly absorbed but cause GI mucosal irritation

Certain hydrocarbons have unique toxicities:

Carbon tetrachloride – hepatic toxicity

Methylene chloride – carbon monoxide

Benzene – AML

Nitrobenzene, aniline - Methhemoglobinemia

Aspiration pneumonitis

(cough or gag)

Inactivation of type2

pneumocytes

Surfactant deficiency

Page 16: Poisonings in Paediatrics

Contd.. Kerosene & paraffin oils young children

Kerosene toxicity neonates Transdermal absorption also cause toxicity

IV kerosene drug abusers major lung injury

Halogenated hydrocarbons sensitizes myocardium endogenous catecholamines

This may result in dysarythmia and ‘sudden sniffing death’

Chronic abuse cerebral atrophy , peripheral neuropathy , kidney disease,etc

Page 17: Poisonings in Paediatrics

Clinical & Lab manifestations: Mild CNS depression is common & sometimes ventricular dysrhythmias are associated

Aspiration cough

Chest X-Ray shows abnormality within 6hrs of exposure,

pneumatocele appear after 2-3weeks of exposure,

x-ray remains abnormal even after patient is clinically normal.

Resp. symptoms ARDS or respiratory failure

Fever & leucocytosis common signs in patients with pneumonitis

Page 18: Poisonings in Paediatrics

Treatment: Contraindicated emesis & gastric lavage

Activated charcoal not useful

Management is symptomatic with preservation of airway in unconscious patients.

Standard Mech. Ventilation, High Freq. Ventilation & ECMO ARDS , resp. failure, pneumonitis

Dysrythmias b-blockers usually esmolol

Page 19: Poisonings in Paediatrics

Organophosphorus poisoning: MC organophosphates & carbamates cholinesterase enzymes unintentional

Pathophysiology : binds & inhibits AchE increased Ach at synapses

If untreated, OrgP. Forms permanent bonds to AchE ’aging’

Carbamates form temporary bonds with enzymes.

Reactivation weeks to months , in organophosphates.

<24hrs, in carbamates .

Page 20: Poisonings in Paediatrics

Clinical & Lab manifestations: Clinical effects depends on accumulations at peripheral nicotinic & muscarinic synapses.

Symptoms : carbamates < organophospahtes

Symptoms for cholinergic excess “ DUMBBLES”

Nicotinic signs muscle weakness, fasciculations, tremors , hypoventilation, hypertension ,

tachycardia, dysrhythmias, coma, seizures, respiratory failures.

Diagnosis history & physical findings

Early reported cases RBC cholinesterase & pseudocholinesterase in labs.

Page 21: Poisonings in Paediatrics

Treatment: Basic decontamination with washing with soap, water & removing exposed clothes immediately.

Activated charcoal controversial based on recent suggestions of its limited values

Fluid & electrolyte replacement is done.

TWO antidotes : atrophine & pralidoxime

Atrophine 0.05-0.1 mg/kg repeated q5-10min as needed (IV/ET)

Pralidoxime 25-50 mg/kg over 5-10 min (max,200 mg/min); can be repeated

after 1-2 hr, then q10-12hr as needed. (IV/IM)

Page 22: Poisonings in Paediatrics

Contd.. Large doses of atrophine intermittent bolus or through infusions to control symptoms,

targeted to resolve respiratory secretions & bronchospasm.

Tachycardia can result from nicotinic effects

Pralidoxime breaks bond b/w organophosphate and the reactivating enzymes,

effective only before permanent bond is formed.

In carbamtes, pralidoxime is not needed as the bond degrades spontaneously.

Without treatment, symptoms persist for weeks which require supportive care.

Even with treatment, patients may develop delayed polyneuropathy.

Page 23: Poisonings in Paediatrics

Iron Intoxication

• GI Toxicity• Stability for 48hrs• Ciruclatory shock• Metabolic acidosis &

Myocardial dysfunction

Ferrous Sulfate

Page 24: Poisonings in Paediatrics

Longterm hepatic fibrosis &GI scaring

GI symptoms are seen 15 to 30mg/kg

No significant toxicity <50mg/kg

Lethal dose 200 to 500mg/kg

Increased serum iron levels >500ug/dl casuses severe toxicity

Child develops complication after few hours or after a latent period of 1-2hrs.

Vomiting , diarrohea, S.glucose,leukocyte, abdominal radiograpgh iron levels >300ug/dl

Page 25: Poisonings in Paediatrics

Treatment:Gastric emptying stomach wash with sodium bicarbonate

IV sod. Bicarbonate 3mg/kg diluted with 5% dextrose acidosis

Fluid resuscitation may be necessary

Iron chelated with IV deferoxamine (15mg/kg/hr) until S.iron lowers <300ug/dl or stoppage vine rose color urine

Renal failure dialysis is required to remove deferoxamine iron complexes.

Page 26: Poisonings in Paediatrics

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