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Poisoning in Poisoning in Children Children Kent R. Olson, MD Medical Director, San Francisco Division California Poison Control System Clinical Professor of Medicine, Pediatrics and Pharmacy, UCSF

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Poisoning in ChildrenPoisoning in Children

Kent R. Olson, MDMedical Director, San Francisco Division

California Poison Control System

Clinical Professor of Medicine, Pediatrics and Pharmacy, UCSF

Case study:

• A 2 year old child is found with a bottle of his mother’s prenatal vitamins

• Spontaneous vomiting after 30 minutes• Paramedics report systolic BP 70/p, HR

130/min

Most common pediatric exposures*

Category Hazard Factor• Cosmetics 0.2• Cleaning agents 0.9• Plants 0.1• Analgesics 0.6• Cough & cold preparations0.5• Hydrocarbons 2.2

Data from AAPCC 1985-1989

Relative risk of death/major effect

Category Hazard Factor• Rattlesnake bite 244• Strychnine 50• Alkaline drain cleaner 22• Organophosphates 5.6• Anticoagulants 0.9• Cosmetics 0.2

Pediatric poisoning deaths(AAPCC 1985-1989)

Pharmaceuticals Hazard Factor• Iron 8.5• Tricyclic antidepressants 17.7• Cardiovascular drugs 8.1

Non-pharmaceuticals Hazard Factor• Pesticides 2.1• Hydrocarbons 2.2• Methanol 5.1

More recent data - AAPCC 199924 deaths in children < 6

Pharmaceuticals• Opioids (3)• Iron (1)• Nifedipine (1)

Non-pharmaceuticals• Carbon monoxide (7)• Hydrocarbons (3)• Ammonium bifluoride (2)

Case 1: Abdominal

X-ray

Iron poisoning in children

• Leading cause of childhood poisoning deaths

• Pathophysiology:– corrosive effect on GI tract– cellular toxin

• Toxic dose > 40-60 mg/kg elemental Fe– adult strength preparations much more likely

to cause toxicity than children’s chewables

Iron poisoning: clinical findings

• Vomiting• Diarrhea• Hypotension• Metabolic acidosis• Leukocytosis, hyperglycemia• Radiopaque pills on plain x-ray• Late complication: hepatic failure

Treatment of iron poisoning

• Volume replacement– IV crystalloid boluses

• Chelation therapy– deferoxamine (Desferal) is specific chelator

– Iron chelate complex “vin-rose” urine

– IV route preferred (don’t use IM “test dose”)– avoid prolonged deferoxamine therapy

Gut decontamination for iron ingestion

• Home:– consider ipecac-induced emesis if recent OD– argument against ipecac: it masks

spontaneous vomiting

• Hospital:– ipecac or gastric lavage? Neither very effective– lavage with HCO3, PO4? Dangerous– whole bowel irrigation = best method

Whole bowel irrigation

• Balanced electrolyte solution with non-absorbable polyethylene glycol (PEG)– no electrolyte disturbance– no net fluid gain or loss– well-tolerated

• Method: GoLytelyGoLytely™™ or ColyteColyte™™– 500 mL/hour by gastric tube until rectal

effluent clear– Adolescents/adults: 1-2 L/hr

Case study:

• A toddler is found with an open daily medicine container belonging to his grandmother.

• Usual contents: – Lasix 40 mg– Cardizem-CD 240 mg– Multiple vitamin

• Container is now empty. Child asx.

ECG in a patient with verapamil ODECG in a patient with verapamil OD

Negative InotropicEffects

Negative InotropicEffects

DecreasedAutomaticity& Conduction

DecreasedAutomaticity& Conduction

Dilated VascularSmooth Muscle

Dilated VascularSmooth Muscle

SVRSVRCOCOHRHRAV BlockAV Block

SHOCKSHOCKSHOCKSHOCK

Calcium Channel Blocker PoisoningCalcium Channel Blocker Poisoning

Calcium antagonist toxicity

• Shock caused by combination of:– Decreased automaticity & conduction– Negative inotropic effects– Vasodilation

• Treatment with calcium– most effective for negative inotropic effect– high doses may be needed– in the future: insulin + glucose?

Case study:

• An 18 month old is brought to the ER after a seizure

• No prior seizures• No recent illness or fever• HR 140/min, BP 105/70• Pupils dilated• Skin flushed, dry

Case 2: ECG

Common drug-induced seizures

• Tricyclic antidepressants• Cocaine & amphetamines• Theophylline• Diphenhydramine• Isoniazid (INH)• Phenothiazines• Strychnine• Many others (camphor, lindane, etc)

Case study, cont.

• ECG monitor shows wide QRS complex• Repeat BP 70/p• The child is intubated endotracheally• A therapeutic drug is given:

Tricyclic antidepressant OD

• “Three C’s”– coma– convulsions– cardiac conduction

defects

… AND

•Anticholinergic effects–dilated pupils–tachycardia–jerking movements

Treatment of TCA overdose

• ABCs• No ipecac! (use AC orally or by NG)• Monitor asx child for at least 6 hours• QRS prolongation: – Caused by Na channel block– Rx = Sodium Bicarbonate– 1-2 mEq/kg IV bolus

• Do NOT use physostigmine

Another Case

• A child is found with an open container of “wire wheel cleaner”

• Contents: – ammonium bifluoride– hydrofluoric acid

• Child initially asymptomatic

Fluoride toxicity

• Sources:– wire wheel cleaners, degreasers, rust and

water stain removers– fluoride tablets and drops

• Toxicity:– hypocalcemia (even from dermal exposure)– hyperkalemia– ventricular fibrillation

• Treatment: Calcium (oral and IV)

Case study:

• A 16 year old takes several “happy pills” provided by a friend.

• Develops a headache, vomits once.• In ER:– awake, alert, c/o headache– HR 38/min (w/2nd degree AV block)– BP 166/100 mm

Phenylpropanolamine

• Common OTC product• May be used to get “high”

(not very effective) or as suicidal agent

• Hypertension common, often with reflex bradycardia or even AV block– intracranial hemorrhage may occur

• Treat with vasodilator, e.g. phentolamine, nitroprusside

11-6-2000: FDA’s MedWatch

• “FDA is taking steps to remove phenylpropanolamine hydrochloride from all drug products due to the risk of hemorrhagic stroke...

• “... FDA has significant concerns because of the seriousness of stroke and the inability to predict who is at risk …”

Gut decontamination

• Current consensus:– Gut emptying of limited value– AC alone probably fine in most patients

• Some twists:– SI still useful at home w/in 5-10 min?– Lavage for selected cases?– Role of Whole Bowel Irrigation?– What about home AC?

Anyonefor

charcoal?

Use of ipecac is declining

Year Ipecac used

1983 13.4%

1988 8.4%

1993 3.7%

1998 1.2%

Source: AAPCC 1999

Final “stumper”

• 9 month old being watched by grandmother

• Found flaccid, grunting, with decreased level of consciousness

• HR 70/min, BP 105/59• Respirations agonal, O2 sat 80%• Pupils pinpoint

More information . . .

• No response to naloxone• Treated supportively, eventually recovered

• Initial history: grandmother takes lisinopril, HCTZ

• Also using eye drops for glaucoma

Continued

• Alphagan™ (brimonidine 0.2%) – used for open-angle glaucoma

• Stimulates -2 receptors (similar to clonidine)– CNS depression, bradycardia, HOTN– Peripheral: alpha-agonist can elevate BP

California Poison Control System

• Public Hotline: 1-800-876-4766 (8-POISON)• Health Professionals: 1-800-411-8080• 300,000 exposures/year– 2/3 are kids– also: suicides, occupational, hazmat,

veterinary, consumer product recalls, ...

• Most kids can be managed at home– PCC can communicate with 9-1-1 or

paramedics on scene