PE14.1-3 | Childhood Poisoning — Graded Quiz

Correct. The principal danger from kerosene ingestion is aspiration pneumonitis, NOT systemic toxicity from GI absorption. Inducing emesis forces kerosene back up through the oropharynx, dramatically increasing aspiration risk — particularly in children who may have impaired protective airway reflexes. The pulmonary complication is far more dangerous than the swallowed dose.

Kerosene and other low-viscosity hydrocarbons: NEVER induce emesis or perform gastric lavage. The aspiration risk outweighs any benefit from GI decontamination. Manage supportively with O2 and close respiratory monitoring.

The key reason emesis is contraindicated for kerosene is the aspiration risk. Kerosene is a low-viscosity, high-volatility hydrocarbon; once aspirated, it causes severe chemical pneumonitis. This pulmonary complication is more lethal than GI absorption, so any intervention that risks aspiration (vomiting, lavage) is contraindicated.

Correct. Initial aspiration pneumonitis from kerosene is a chemical injury. Antibiotics are NOT given routinely but ARE indicated when secondary bacterial pneumonia is suspected — evidenced here by fever, purulent sputum, and progressive infiltrates at 8 hours. Corticosteroids are not standard and may worsen infection.

Aspiration pneumonitis (chemical) = supportive care, O2, monitoring; antibiotics are NOT routine. Add antibiotics ONLY when secondary bacterial pneumonia supervenes (fever, purulent secretions, progressive infiltrates). Corticosteroids are not recommended.

Secondary bacterial pneumonia superimposed on chemical aspiration pneumonitis is an important complication — indicated by fever, purulent sputum, and progressive infiltrates. Antibiotics are appropriate here. Routine prophylactic antibiotics and corticosteroids are not recommended for pure chemical aspiration pneumonitis.

Correct. Muscarinic effects of OP poisoning include the SLUDGE syndrome (salivation, lacrimation, urination, defaecation, GI distress, emesis), bradycardia, miosis, bronchospasm, and bronchorrhoea. Nicotinic effects — acting at neuromuscular junctions and autonomic ganglia — include muscle fasciculations, weakness, and in severe cases respiratory muscle paralysis. Atropine only reverses muscarinic effects.

OP poisoning features: MUSCARINIC = SLUDGE + bradycardia + bronchospasm (reversed by atropine); NICOTINIC = muscle fasciculations + weakness + respiratory paralysis (not reversed by atropine; requires ventilatory support); CNS = seizures + coma (treated with benzodiazepines).

The SLUDGE syndrome (salivation, lacrimation, urination, defaecation, GI distress, emesis) represents MUSCARINIC excess. Nicotinic receptor stimulation at the neuromuscular junction causes muscle fasciculations, weakness, and respiratory muscle paralysis. Atropine blocks only the muscarinic effects; muscle paralysis requires supportive ventilation.

Correct. Pralidoxime must be infused slowly (over 15–30 minutes). Rapid IV injection can cause hypertension, tachycardia, and paradoxical worsening of neuromuscular blockade. PAM and atropine act via different mechanisms and are complementary — atropine should not be stopped after PAM is given.

PAM (pralidoxime) dose: 25–50 mg/kg IV over 15–30 minutes (NOT rapid bolus). It must be given within 24–48 hours to be effective. It is used alongside atropine, not instead of it — both are continued simultaneously as they act at different receptor sites.

PAM (pralidoxime) infusion must be SLOW (15–30 minutes) to avoid hypertension and worsening neuromuscular effects from rapid administration. PAM and atropine complement each other — PAM reactivates cholinesterase while atropine blocks muscarinic receptors; they act at different sites and must both continue.

Correct. The Rumack-Matthew nomogram is valid only for serum paracetamol levels drawn AT LEAST 4 hours after ingestion. Levels drawn earlier reflect ongoing absorption and overestimate the peak; they cannot be reliably plotted. The nomogram line indicates whether NAC is indicated based on the measured level versus time.

Rumack-Matthew nomogram: requires a serum paracetamol level at ≥4 hours post-ingestion. Earlier levels cannot be plotted. The nomogram is used in all age groups. NAC is most effective within 8–10 hours; efficacy decreases progressively after 10 hours but it should still be given up to 24 hours.

The Rumack-Matthew nomogram requires a serum paracetamol level drawn at ≥4 hours post-ingestion. Levels before 4 hours are unreliable because absorption may be ongoing. The nomogram applies to all age groups, and paediatric poisoning management follows the same nomogram principles.

Correct. The standard IV NAC protocol (21-hour regimen): loading dose 150 mg/kg in 5% dextrose over 1 hour, then 50 mg/kg over 4 hours, then 100 mg/kg over 16 hours. The entire regimen is weight-based. This is the protocol used for children and adults alike (with volume adjustments for small children to prevent hyponatraemia from excess free water).

IV NAC protocol for paracetamol poisoning: 150 mg/kg over 1 hour (loading), then 50 mg/kg over 4 hours, then 100 mg/kg over 16 hours. Total = 300 mg/kg over 21 hours. Always weight-based; adjust diluent volume for small children to prevent hyponatraemia.

The standard IV NAC protocol is: 150 mg/kg over 1 hour (loading) → 50 mg/kg over 4 hours → 100 mg/kg over 16 hours. This weight-based 21-hour regimen is used for all age groups. For small children, the volume of 5% dextrose diluent must be age-adjusted to prevent hyponatraemia.

Correct. PAM reactivates inhibited acetylcholinesterase before the enzyme-OP complex undergoes irreversible 'ageing'. Ageing occurs within 24–48 hours (varies with OP compound — some age faster, e.g. soman ages within minutes). At 30 hours, significant ageing has likely occurred with most common OP pesticides, making PAM of limited or no benefit. Atropine remains useful for muscarinic symptoms regardless of ageing.

The 24–48 hour PAM effectiveness window is compound-specific; ageing is progressive and not a hard cliff at 48 hours. Most agricultural OP pesticides show significant ageing by 24–30 hours. Clinical lesson: initiate PAM as EARLY as possible. Beyond the ageing window, atropine remains the treatment mainstay for muscarinic symptoms.

PAM is effective ONLY before cholinesterase ageing — the window is 24–48 hours (compound-dependent). At 30 hours, considerable ageing has likely occurred with common organophosphate pesticides, so PAM may provide little benefit. Atropine continues to manage muscarinic symptoms regardless of ageing. The critical teaching is: START PAM EARLY.

Correct. The minimum observation period for kerosene ingestion is 6–8 hours. Even though the child is currently asymptomatic, aspiration pneumonitis symptoms (and CXR changes) can be delayed by 4–6 hours. Discharge before this window closes risks the child deteriorating at home without medical support. Safe discharge is appropriate only after 6–8 hours of uneventful observation.

Minimum observation for kerosene ingestion: 6–8 hours. Discharge only after uneventful observation with normal respiratory parameters. Provide clear written return precautions (any cough, fever, breathing difficulty = return immediately). CXR changes lag 4–6 hours; don't discharge at 4 hours on a normal CXR alone.

Asymptomatic presentation at 4 hours does NOT mean safe discharge — aspiration pneumonitis symptoms and CXR changes can appear up to 6 hours or later. The recommended observation period is at least 6–8 hours of stable clinical and respiratory parameters. Mandatory 72-hour admission and bronchoscopy are not required for uncomplicated kerosene ingestion.

Correct. Paracetamol hepatotoxicity produces a severe hepatocellular injury pattern — AST and ALT may exceed 1,000 IU/L (sometimes reaching 10,000+) in severe cases. This peaks at 24–72 hours after ingestion. The lag (child appears well initially) is why prompt level-guided NAC is essential before clinical or biochemical manifestation.

Paracetamol hepatotoxicity: delayed hepatocellular injury — transaminases (AST/ALT) rise 24–72 hours after ingestion, may exceed 1,000–10,000 IU/L. The initial asymptomatic phase is deceptive. NAC must be given BEFORE LFT abnormalities appear, guided by the 4-hour serum level + Rumack-Matthew nomogram.

Paracetamol hepatotoxicity causes a HEPATOCELLULAR pattern — massively elevated transaminases (AST/ALT often >1000 IU/L, sometimes much higher) peaking 24–72 hours post-ingestion. Cholestatic and isolated ALP-rise patterns are not characteristic. Transaminase rise within 1–2 hours is incorrect — the biochemical manifestation is delayed.

Correct. Atropine reverses the MUSCARINIC features of OP poisoning (bronchospasm, bronchorrhoea, bradycardia, SLUDGE) but has NO effect on NICOTINIC receptor-mediated effects at the neuromuscular junction — specifically, respiratory muscle paralysis (diaphragm and intercostal muscle weakness). Nicotinic-driven respiratory failure is the principal cause of death in OP poisoning when secretion control is achieved but muscles fail. It requires mechanical ventilatory support.

OP poisoning respiratory failure has TWO mechanisms: (1) Muscarinic — bronchospasm + bronchorrhoea → reversed by atropine. (2) Nicotinic — respiratory muscle paralysis → requires mechanical ventilation; atropine has NO effect. Adequate atropinisation controls the secretion component; ventilatory support addresses the muscle paralysis component.

Atropine does not cause paradoxical bronchoconstriction. The key mechanism of respiratory failure refractory to atropine is NICOTINIC receptor stimulation at the neuromuscular junction causing respiratory muscle (diaphragm, intercostals) paralysis — which atropine cannot treat. Mechanical ventilation is required.