Toxins/Ingestions

Management

1. Evaluate and treat the ABCD's (Airway, Breathing, Circulation, Disability) to stabilize the patient.

   • Airway: Gag reflex, patency of airway, careful monitoring even in awake patient as they can deteriorate quickly. Consider intubation if unable to protect airway.

   • Breathing: Evaluate SpO2 and PCO2 if any concern for impaired breathing. Supplemental oxygen or even intubation/mechanical ventilation may be needed for significant impairment.

   • Circulation: Evaluate blood pressure and heat rate. Obtain peripheral IV access.  EKG should generally be obtained if suspecting an occult ingestion.

   • Disability: Monitor mental status. Check glucose as hypoglycemia is a common cause of AMS is poisoned patients. Consider naloxone if opioid ingestion is highly suspected (generally the use of flumazenil for benzodiazapene ingestion is not recommended due to the risk of precipitating seizures)

Decontamination

• • Activated charcoal is the preferred method of GI decontamination in children. Dose 1 g/kg (max 50-60g) given either orally or via NG tube. Can repeat the dose 0.5 g/kg q4-6 hours. Best given as soon as possible after ingestion (ideally within 1 hour). May cause constipation and vomiting. Absolute contraindications include bowel obstruction or an unprotected airway/depressed level of consciousness. Activated charcoal is not recommended for: heavy metals (Iron, mercury, arsenic etc), Inorganic ions (lithium, calcium, etc), Corrosives (acids/alkalis), Hydrocarbons (alkanes, aromatic hydrocarbons), Alcohols (acetone, ethanol, ethylene glycol, methanol). 

  • Syrup of ipecac: Not recommended by AAP for ingestions.1

  • Gastric lavage is no longer recommended by the American Academy of Clinical Toxicology or the European Association of Poison Centers and Clinical Toxicologists

  • Whole bowel irrigation: Essentially, polyetheylene glycol via NG tube at 20-40 ml/kg/hr until rectal effluent is clear. Max doses: 9 mo-6 yrs (500 ml/hr), 6-12 years (1000 ml/hr), >12 years (2000 ml/hr). May be useful in situations where activated charcoal is ineffective (ie lithium ingestion) or when enteric-coated or sustained release preparations.

Diagnosis of poisoning:

• • Poison Control 1-800-222-1222 can be extremely helpful in both diagnosis of an ingested substance as well as subsequent management/disposition guidelines

    • History 

• • • Physical Exam: 

• • • Labs:

    • blood glucose,

    • blood gas with cooximetry (to evaluate methemoglobinemia or carbon monoxide poisoning)

    • electrolytes

    • serum osmolarity (ie osmolar and anion gap with toxic alcohol ingestion)

    • LFTs

    • acetaminophen level

    • salicylate level

    • urinalysis

    • urine pregnancy test

    • urine drug screen

    • urine GC-MS (gas chromotography mass spectrometry) for more precise identification of possible toxic substances.

• Disposition

  • Based on patient's clinical status and expected trajectory and duration of toxicity. Consider social work involvement if concern for suboptimal home environment

Antidotes:

Courtesy of Richard Pierce, MD

• Opioids: Naloxone. Of note, the elimination half-life of naloxone is 60-90 minutes so the patient may need further doses if they have taken a longer acting opioid. Dosing 0.001-0.005 mg/kg/dose for reversal of respiratory depression, 0.1 mg/kg for full reversal (max dose of 2 mg). May need to repeat q20-60 minutes. 

• Benzodiazepenes: Flumazenil. Generally not recommended if concern for precipitating seizure (ie chronic benzo use, lowered seizure threshold, etc). Dose 0.01 mg/kg.

• Acetaminophen: N-Acetylcysteine

• Aspirin: Sodium Bicarbonate

• Serotonin syndrome: Cyproheptadine (not dantrolene)

• Methemoglobinemia: methylene blue

• Organophosphates/Cholinergics: Atropine/Pralidoxime

• Calcium channel blockers: Calcium chloride, insulin/dextrose, glucagon

• Neuroleptic malignant syndrome: Dantrolene

• Cyanide Toxicity (ie from nitroprusside or a house fire- toxic in that it inhibits cytochrome C in your electron transport chain and thus impairs oxygen utilization/oxidative phosphorylation): Hydroxycobalamin, sodium thiosulfate/sodium nitrite

• TCAs: Sodium Bicarbonate

• Heavy metals: EDTA or DMSA chelators

• Iron: Deferoxamine

• Digoxin: Digifab

• Ethylene glycol: fomepizole or ethanol

• Heparin: protamine

• Isoniazid: pyridoxine

• Carbon Monoxide: Toxic in that CO has a much higher affinity for O2 and then also alters the affinity of Hgb to existing oxygen-shifting the Hb Oxygen dissociation curve to the left and impairing oxygen delivery). Patients present cherry red, often in the winter due to furnace exposure etc., normal SpO2 but signs of hypoxia. Diagnose via cooximetry on arterial blood gas analysis. Treat with 100% Oxygen via nonrebreather mask as it changes the half life of carboxyhemoglobin to ~80 minutes instead of ~ 300 minutes). Can also use hyperbaric chamber in extreme situations. 

• Methotrexate: Leucovorin

References

1. American Academy of Pediatrics Committee on Injury, Violence, and PoisonPrevention. Poison treatment in the home. American Academy of PediatricsCommittee on Injury, Violence, and Poison Prevention. Pediatrics. 2003Nov;112(5):1182-5. PubMed PMID: 14595067.

2. Life in the Fast Lane Toxicology Library

3. Snake envenomation algorithm