Poisoning Flashcards
What clinical presentations could indicate poisoning?
Any child who presents with unexplained symptoms including altered mental status, seizure, cardiovascular compromise, or metabolic abnormality should be considered to have ingested a poison until proven otherwise.
What is important in directing interventions?
Determination of all substances that the child was exposed to, type of medication, amount of medication, and time of exposure
What are the most common agents?
- Cosmetics
- Personal care products
- Cleaning solutions
- Analgesics
- Plants
- Foreign bodies
- directly accesible in the childs environment
Epidemiology of poisoning?
- 50% occur in children <6 yr old, with the highest number of exposures occurring in 1 and 2 yr olds
- Almost all these exposures are unintentional and reflect the propensity for young children to put virtually anything in their mouth (unintentional, exploratory ingestions.) - 6-12 yr are much less common, involving only approximately 10% of all reported pediatric exposures
- 2nd peak in pediatric exposures occurs in adolescence
Why poisoning in <5 years is common?
- Curious
- Explore environment using all senses
- Prone to mouthing things
- Lack of sense of danger
Why poisoning in adolescence happens?
- Usually deliberate ingestion
- Deliberate self harm
- Exploratory behaviour (recreational drugs)
Note: Poisoning in middle childhood (age 6–11 years) is rare
Routes of poisoning?
- Ingestion
- Inhalation
- Ocular exposure
- Dermal exposure
- Mucous membrane involvement
- Parenteral exposure
History taking on environment of poisoned patient?
- witness
- time of ingestion
- site of ingestion
- illness of family member
- medication of family members
- open containers
History taking of a poisoned patient?
- intentionally
- past medical history
- current medications
- known drug allergies
- time of symptom onset
- prior medical management
- substance found in the patients hand or mouth
History taking for the poisonous toxin?
- agents involved
- exact ingredient
- dose - max
- concentration - strength
- route of exposure
- formulation - enteric coated or extended release
Past medical hx in poisoning?
- psychiatric illnesses
- pregnancy in teens
Social hx in poisoning?
- social environment (caregivers, visitors, grandparents, recent parties or social gatherings)
- social circumstances (new baby, parent’s illness, financial stress)
- neglect
What should parents do in the event of poisoning?
Parents should bring the product containers and medication labels
- Parents may minimize their description of the child’s exposure to a toxin in an attempt to deny the threat of injury or to assuage their guilt that such an episode occurred
Odor signs of poisoning and causes?
- alcohol - ethanol
- garlic - organophosphate
Ocular signs of poisoning and their causes?
- miosis - organophosphates
- mydriasis - atropine, antihistamines
- nystagmus - phenytoin, barbiturates
- lacrimation - organophosphates, irritant vapor/gas
Cutaneous signs of poisoning and causes?
diaphoresis - Organophosphates, muscarinic mushrooms, aspirin
Oral signs of poisoning and their causes?
- dry mouth - amphetamine, anticholinergics, antihistamine
- burns and dysphagia - corrosives
- salivation - Organophosphates, salicylate, corrosives, ketamine
- hematemesis - Corrosives, iron, salicylates, NSAIDs
Intestinal signs of poisoning and their causes?
diarrhea - Antimicrobials, iron, cholinergics
Respiratory signs of poisoning and their causes?
- depressed resp. - Alcohol, narcotics, barbiturates
- increased resp. - aspirin, CO
- pulmonary edema - Hydrocarbons, organophosphates
Mechanism of action of CO poisoning?
- CO binds reversibly to hemoglobin with about 250 times greater affinity than oxygen
- In addition, CO has an even higher affinity for cardiac myoglobin, further worsening cardiac output and tissue oxygenation
Cardiac signs of poisoning and their causes?
- tachycardia - atropine, aspirin
- bradycardia - organophosphates, beta and calcium channel blockers
- hypotension - barbiturates, iron, beta and calcium channel blockers
CNS manifestations of poisoning + causes?
- ataxia - alcohol, narcotics
- coma - sedative, alcohol, narcotics
- hyperpyrexia - anticholinergics
- muscle fasciculation - organophosphates
- peripheral neuropathy - organophosphates
- muscle rigidity - cyclic antidepressants
- altered behaviour - alcohol, anticholinergics
Clinical manifestations of acetaminophen poisoning?
- Nausea
- vomiting
- pallor
- delayed jaundice
- hepatic failure (72-96 hr)
Clinical features of anticholinergics poisoning?
- Mania
- delirium
- fever
- red dry skin
- dry mouth
- tachycardia
- mydriasis
- urinary retention
Clinical features of CO poisoning?
- Headache
- dizziness
- coma
- other systems affected
Clinical features of iron poisoning?
- Vomiting (bloody)
- diarrhea
- hypotension
- hepatic failure
- leukocytosis
- hyperglycemia
- radiopaque pills on KUB
- late intestinal stricture
9.Yersiniasepsis
Clinical features of cholinergic poisoning?
- Miosis
- salivation
- urination
- diaphoresis
- lacrimation
- bronchospasm (bronchorrhea)
- muscle weakness and fasciculations
- emesis
- defecation
- coma
- confusion
- pulmonary edema
- bradycardia
Clinical features of salicylates?
- Tachypnea
- fever
- lethargy
- coma
5.vomiting - diaphoresis
- alkalosis (early)
- acidosis (late)
Clinical features of cyclic antidepressants?
- Coma
- convulsions
- mydriasis
- hyperreflexia
- arrhythmia (prolonged Q-T interval)
- cardiac arrest
- shock
Complications?
- coma
- toxicity
- metabolic acidosis
- heart rhythm aberrations
- gastrointestinal symptoms
- seizures
Ddx of coma?
- cerebrovascular accident
- Asphyxia
- Meningitis
- Encephalitis
- Cerebral malaria
Describe pulmonary toxicity?
direct toxicity by hydrocarbons
- risk of producing aspiration pneumonia (low viscosity, low surface tension, and high volatility)
- Risk increased when emesis is induced.
- Emesis or lavage shouldnotbe initiated in volatile hydrocarbons ingestions
Oral and oesophageal symptoms caused by alkali ingestion?
- Dysphagia
- epigastric pain
- oral mucosal burns
- low-grade fever.
Complications of alkali ingestion?
- Alkali agents causes full-thickness liquefaction necrosis
- When the esophageal lesions heal, strictures form
- long-term risk of esophageal carcinoma
Oral and oesophageal symptoms of ingestion of acid agents?
- can injure the lungs (with hydrochloric acid fumes), oral mucosa, esophagus, and stomach.
- taste sour, children stop drinking, limiting the injury. - produce a coagulation necrosis, limiting deep injury
4 foci of treatment of poisoning?
- supportive care
- Decontamination
- enhanced elimination
- Specific antidotes.
Describe supportive care?
- protecting and maintaining the airway
- establishing effective breathing
- supporting the circulation
- If the level of consciousness is depressed and a toxic substance is suspected, glucose (1 g/kg intravenously), 100% oxygen.
Describe gastrointestinal decontamination?
- Gastric lavage
- Single dose activated charcoal
- Activated charcoal has exceptionally high surface area –has the ability to adsorb potentially poisonous substances, reducing their bioavailability and hence toxicity
Describe enhanced elimination?
- Multiple dose activated charcoal
- Multiple dose activated charcoal: every 4-6 hr (for 4 doses). - Alkalization of urine
- achieved by administration of sodium bicarbonate. Increases renal excretion of salicylates, phenobarbitone, methotraxate - Dialysis
Investigations?
- Chest x-ray
- pneumonitis e.g., hydrocarbon aspiration, noncardiogenic pulmonary edema e.g., salicylate toxicity, or a foreign body. - Abdominal x-ray
- foreign bodies
- radiopaque tablets - Upper endoscopy
- Caustic ingestions
Prognosis?
- Most have minimal or no toxicity
- Intentional ingestionscause higher morbidity and mortality
Prevention?
Parents educate regarding :
- Safe storage of medications (e.g child-resistant packaging)
Antidote for acetaminophen?
N-Acetylcysteine
- Most effective within 16 hr of ingestion
Antidote for benzodiazepine poisoning?
Flumazenil
- Possible seizures, arrhythmias
- DO NOT USE FOR UNKNOWN INGESTIONS
Beta blocking agents poisoning antidote?
glucagon
- increases heart rate and myocardial contractility, and improves atrioventricular conduction
Antidote for CO poisoning?
oxygen
- Half-life of carboxyhemoglobin is 5 hr in room air but 1.5 hr in 100% O2
Antidote for iron poisoning?
Deferoxamine
- Hypotension (worse with rapid infusion rates)
- Treatment is urgent and involves chelating iron in plasma. As an immediate measure, raw egg and milk help bind iron in the stomach. Iron chelation therapy is required for severe toxicity
Antidote for opiate poisoning?
Naloxone
- causes no respiratory depression
Antidote for organophosphate poisoning?
- atropine
- blocks acetylcholine - Pralidoxime (2 PAM; Protopam)
- disrupts phosphate-cholinesterase bond
Antidote for cyclic antidepressants poisoning?
sodium bicarbonate
- Follow potassium levels and replace as needed
