Pediatrics - Poisonings and Toxicologic Emergencies (Sicilio) PDF

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Peds: Poisonings and Toxicologic Emergencies (Sicilio) -

Often, history is sketchy and multiple drugs may have been ingested; goal is to stabilize, diagnose, decontaminate, improve elimination of toxin, provide supportive care, and provide specific antidotes Checklist A – Airway B – Breathing C – Circulation, Contact Poison Control Center Consider multiple IV or intraosseous (IO) lines D – Dextrose, De Brain, Decontaminate Ipecac – emetic, contraindicated Activated Charcoal: see below Gastric Lavage: ONLY use in rare cases – recent and potentially lethal ingestion E – Environment, Eliminate Survey environment for exposure Offer specific antidotes, if available Consider enhancing elimination (if appropriate) Wear gloves to prevent your own poisoning AMS  oxygen, glucose, naloxone (Narcan) Malnourished/Alcoholic  thiamine History/Collect Medications/empty bottles Treatments: Activated Charcoal: antidotes/highly absorbent powder that binds chemicals w/n minutes of contact, preventing GI absorption and subsequent toxicity Repetitive doses may enhance elimination of acetaminophen, phenobarbital, salicylates, theophylline Give w/n 1 hour of toxin ingestion Can mix with choc syrup/organge juice Drink slowly to decrease probability of emesis CONTRAINDICATIONS: There is NO benefit if toxin poorly absorbed by AC – metals like iron, arsenic, lead, mercury, inorganic ion lithium, corrosives like acids/alkalis, hydrocarbons (gasoline), alcohols Sedated patient, unable to protect airway, at increased risk of aspiration (only do this if patient intubated first to protect airway) – DO NOT intubate just to give AC Intestinal obstruction – can’t clear GI contents Poisoned Patient’s Physical Exam Physical exam (special attention to pupils, skin, neurologic status) Reassess frequently Psychiatric consult, if intentional overdose Review lab and recommendations Helpful Smells (tell Poison Control!) Bitter Almonds  cyanide Garlic  arsenic, organophosphates (insecticides) Mothballs  camphor, naphthalene Pears – chloral hydrate Rotten eggs  sulfur-containing compounds

Specific Drug Overdoses Acetaminophen  fatal/nonfatal hepatic necrosis Toxic dose: 150 mg/kg (child) or 7.5/10 g (adolescents) Measure serum levels at 4+ hours after acute OD and plot on Rumack-Matthew acetaminophen nomogram to determine if it is above treatment line to use NAC (this cannot be used for OD > 24 hours prior or repeated supratherapeutic oral ingestions) Toxidrome: Stage 1 (up to 24 hours): Generally asymptomatic, may have N/V; in large doses  lethargy/malaise Stage 2 (24-72 hours): RUq pain, inc liver func tests, possible nephrotoxicity (inc BUN, creatinine, oliguria), and/or pancreatitis (inc amylase/lipase) Stage 3 (72-96 hours): evidence of liver failure, possible renal failure, multi-organ failure, death Stage 4 (4-14 days): recovery Treatment: Activated Charcoal Antidote: N-Aceytylcysteine (NAC): prevent hepatic injury by restoring hepatic glutathione stores begin tx w/n 8 hours of ingestion in pt whose levels are above toxicity line on RM nomogram use for patients with known OD ingestion Oral regimen: 72-hou, 18 doses, w/ loading dose twice subsequent maintenance doses IV regimen: 21 hours  hepatoxicity (~60-2%) & mortality (~51%) Monitor presence/absence of inc serum [ALT] Anti-Cholinergics Toxidrome: fever, flushed appearance, toxic psychosis, coma, seizures, blurred vision, mydriasis, dry mucus membranes, tachycardia, ileus, urinary retention Mnemonic: Red as a beat  cutaneous vasodilation Dry as a bone  anhidrosis (dry skin) Host as a hare  anhidrotic hyperthermia Blind as a bat  nonreactive mydriasis Mad as a hatter  delirium, hallucinations Full as a flask  urinary retention Carbon Monoxide Toxidrome: HA, flu-like syndrome, lethargy, dz, coma Symptoms often seen in several family members Standard sPO can’t screen for CO bc it doesn’t differentiation carboxyHb from oxyHb Non-smokers: COHb 15% Treatment: O2, Hyperbaric oxygen therapy if COHb over >15% Mnemonic: CAT MUDPILES for metabolic acidosis Cholinergics

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Toxidrome: SLUDGE: salivation, lacrimation, urination, defecation, gastric emesis. Also, miosis, bronchorrhea, Sz Mnemonic: SLUDGE Cyanide Toxidrome: feeling of impedning doom, sudden coma, hypotension, metabolic acidosis Treatment: AC: acetaminophen, phenobarbital, salicylates, theophylline Mnemonic: CAT MUDPILES for metabolic acidosis Helpful Smells: bitter almond Ethanol Toxidrome: lethargy, ataxia, hypoglycemia, osmolar gap >/=10, metabolic acidosis Treatment: AC: acetaminophen, phenobarbital, salicylates, theophylline Helpful Smells: characteristic ethanol odor Mnemonic: CAT MUDPILES for metabolic acidosis Ethylene Glycol (Anti-Freeze) Toxidrome: lethargy or coma, metabolic acidosis, osmolar gap >/=10, active urinary sediment, crystalluria Treatment: Hemodialysis Mnemonic: CAT MUDPILES for metabolic acidosis Isoniazid (anti-TB drug) Toxidrome: seizures, hyperglycemia, metabolic acidosis, history of TB in patient/family member Mnemonic: CAT MUDPILES for metabolic acidosis Methanol Toxidrome: blurred vision, sluggish pupils, hyperemic retina, severe metabolic acidosis, osmolar gap >/=10 Treatment: hemodialysis Mnemonic: CAT MUDPILES for metabolic acidosis Opiates Toxidrome: CNS depression, shallow respiration, miosis, occasionaly hypotension and hypothermia Mnemonic: depression of everything Organophosphates (Insecticides) Absence of anticholinergic signs (tachycardia, mydriasis, decreased bowel sounds, dry skin) Toxidrome: SLUDGE/BBB: salivation, lacrimation, urination, defecation, gastric emesis, bronchorrhea (too much fluid in lungs), bronchospasm, bradycardia. Also, miosis, central respiratory dep, lethargy, seizures, paralysis, decreased DTRs Antidote: Atropine and 2-PAM Mnemonic: SLUDGE/BBB Helpful Smells: garlic Phenyclidine (PCP, Angel Dust) Toxidrome: rotatory nystagmus, delirium, combative, catatonia, convulsions, coma, sometimes fever Phenothiazines (anti-emetics) Toxidrome: oculogyric crisis, dystonia, opisthotonus Salicylates (aspirin) Use of aspirin in children has decreased since risk associated with Reye Syndrome and incidence of unintentional OD in toddlers has declined with limitation of dose in aspirin in chewable, flavored tablets to 81 mg/tab, restriction of number of tablets/bottle to 36, and child-resistnat packaging

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Toxidrome: fever, tachypnea, hyperpnea, lethargy, respiratory alkalosis followed by metabolic acidosis, hyper/hypoglycemia, noncardiac pulmonary edema, CNS depression OD activates respiratory center of medulla  tachypnea, respiratory alkalosis, inc renal elimination of HCO3, and insensible fluid losses OD also interferes with cellular metabolism (uncoupling of ox phos)  metabolic acidosis, hyperpyrexia, fluid loss, and hypoglycemia Treatment: alkalinate the urine, activated charcoal, hemodialysis Mnemonic: CAT MUDPILES for metabolic acidosis Sympathometics (amphetamines, ephedrine, epinephrine) Toxidrome: tachycardia, arrhythmias, hypertension, hyperthermia, mydriasis, sweating, restlessness, possible sz

Theophylline (bronchodilator, used for asthma) Toxidrome: protracted emesis, hypotension, tremors, tachycardia, anxiety, refractory seizures (difficult to control) Treatment: activated charcoal, hemodialysis, hemoperfusion Mnemonic: CAT MUDPILES for metabolic acidosis Tricyclic Antidepressants Toxidrome: coma, seizures, mydriasis, arrhythmias, prolonged QRS, metabolic acidosis Treatment: HCO3 Mnemonic: CAT MUDPILES for metabolic acidosis Anion Gap: May classify causes of metabolic acidosis Calculation: [Na+] – ([Cl-] + [HCO3]) Normal: 12 +/- 2 High Anion Gap: usually due to  acid production or  HCO3 production Renal failure ecan   lactic acid/ketoacids Some poisoning Elevated AG metabolic acidosis: Occurs when common poisons  metabolic anions Methanol  formate Ethylene glycol  glycolate, oxalate Salicylates  ketones, lactate CAT MUDPILES C – CO, cyanide, congenital heart failure A – aminoglycosides T – theophylline, toluene (glue-sniffing) M – methanol U – uremia (renal failure) D – DKA, alcoholic/starvation ketoacidosis P – Propylene glycol, paraldehyde I – infx, iron, isoniazid, inborn errors of metabolism L – lactic acidosis E – ethanol (due to lactic acidosis), ethylene glycol S - salicylates...