Transcript Poisoning in Children

Poisoning in Children
Norah Al Khathlan M.D.
Consultant Pediatrician
Consultant Pediatric Intensivist
02/02/08
Poisoning in Children
Goals:
• Learn the pertinent aspects of the history and physical exam relative to
acute poisoning with particular emphasis on clinical recognition of major
toxic syndromes (toxidromes).
• Understand the principles, methods, and controversies of decontamination
and enhancement of elimination of toxins.
• Learn the presenting signs, symptoms, laboratory findings, pathophysiology
and treatment of common therapeutic drug poisonings, drugs of abuse,
natural toxins and general household poisons.
Poisoning in Children
Objectives:
At the end of this lecture the student will be able to :
1. Define poisoning.
2. Identify specific Toxidromes.
3. Identify risk factors for pediatric toxidromes.
4. Differentiate between the different classes of toxidromes.
5. Differentiate the routes of poisoning.
6. Describe the general management of the toxidromes.
7. Outline the management of specific toxidromes:
–
–
–
–
Iron
Salicylates
Paracetamole/ Acetaminophen
Kerosene
Poisoning in Children
• Definition of Poisoning:
– Exposure to a chemical or other agent that adversely
affects functioning of an organism.
• Circumstances of Exposure can be intentional,
accidental, environmental, medicinal or recreational.
• Routes of exposure can be ingestion, injection, inhalation
or cutaneous exposure.
“All substances are poisons...the right dose separates poison from a
remedy.”
Poisoning in Children
• Ingestion of a harmful substance is among the most
•
•
common causes of injury to children less than six years
of age
Toxicology. . . is the science that studies the harmful
effects of drugs, environmental contaminants, and
naturally occurring substances found in food, water, air
and soil.
Poisoning maybe a medical emergency depending on the
substance involved.
Poisoning in Children
Constellation of signs & symptoms seen in
poisoning characterized by the type of
substance.
Major four toxidromes are:
– Anticholinergic
– Sympathomimetic
– Opiates/Sedatives- Hypnotics/ Alcohol
– Cholinergic
Poisoning in Children
Examples:
• ASA
• Acetaminophen
• TCA
• Narcotics & drugs of abuse
• Benzodiazepines
• Iron supplements
• Alcohol
Agents Most Commonly Ingested by Children Less Than Six Years of Age, 1995 to 1998
Shannon M. N Engl J Med 2000;342:186-191
Shannon M. N Engl J Med 2000;342:186-191
Poisoning in Children
Important history points
• What toxic agent/medications were found near the patient?
• What medications are in the home?
• What approximate amount of the “toxic” agent was ingested?
– How much was available before the ingestion?
– How much remained after the ingestion?
• When did the ingestion occur ?
• Were there any characteristic odors at the scene of the ingestion?
• Was the patient alert on discovery?
– Has the patient remained alert since the ingestion?
– How has the patient behaved since the ingestion?
• Does the patient have a history of substance abuse?
Poisoning in Children
Management
General measures:
• Quick assessment & triage
• Identify the culprit.
• Limit absorption:
– Vomiting
– Lavage
– Activated charcoal instillation
Specific:
Poisoning in Children
ABC’s of Toxicology:
• Airway
• Breathing
• Circulation
• Drugs:
• Resuscitation medications if needed
• Universal antidotes
• Draw blood:
• chemistry, coagulation, blood gases, drug levels
• Decontaminate
• Expose / Examine
• Full vitals / Foley / Monitoring
• Give specific antidotes / treatment
Poisoning in Children
• Decontamination:
1. Ocular:
– Flush eyes with saline
2. Dermal:
– Remove contaminated clothing
– Brush off
– Irrigate skin
3. Gastro-intestinal:
– Activated charcoal:
– May Prevent /delay absorption of some drugs/toxins
– Almost always indicated
– Naso/oro-gastric Lavage
– Bowel Irrigation:
–
–
–
–
–
Recent ingestions 4-6 hrs
Awake alert patient
500 cc NS Children / 2000cc adults
Orally / Nasogastric tube
Contraindications…?
Agents Used for Gastrointestinal Decontamination in Children
Shannon M. N Engl J Med 2000;342:186-191
Circumstances under Which Administration of Ipecac Syrup Should Be Avoided
Shannon M. N Engl J Med 2000;342:186-191
Important points
Specific toxidromes
• Acetaminophen:
– Stage I 0-24 hrs
• Early symptoms
–
–
–
–
Mild
Serum acetaminophen level 4 hrs post ingestion
PLOT ON SPECIFIC NOMOGRAM.
No need to repeat levels
• If > 900 µmol/L ---> POSSIBLE RISK
• Nausea, vomiting, malaise and diaphoresis.
• Normal bilirubin Transaminases and PT
Acetaminophen poisoning
• Stage II:
– 24-48 hrs after ingestion.
• Better, less symptoms.
• Elevated bilirubin, transaminases and PT
Acetaminophen poisoning
• Stage III
– 48-96 hrs ( 2- 4 days) after ingestion:
• Hepatic dysfunction
• (Rarely hepatic failure)
• Peak elevations in:
– Bilirubin
– Transaminases may reach > 1000 IU/L
– Prolonged PT
Acetaminophen poisoning
• Stage VI
– 168- 192 hrs (7-8 days)
– Clinical improvement
– LFTs returning to normal
Acetaminophen poisoning
• Probable toxicity should be treated with:
– N-acetylcysteine bolus 140 mg/kg
– Then 70 mg/kg Q 4 hrs for 17 doses.
– Assess hepatic function:
• On presentation
• Daily
– Continue other support
Iron Poisoning
• Five Stages but variable
– Stage 1
• Gastro-intestinal stage: within several hrs of
ingestion:
– V/D. Hematochezia and abdominal pain
– Severe: fluid loss, bleeding, shock(acidosis, tachycardia
+/- hypotension)
– Fever. Lethargy. Coma
Iron Poisoning
• Stage 2
– Quiescent stage: 4-48hrs
• Clinical improvement
• Subtle hemodynamic changes:
– Tachycardia
– Decreased U.O.P.
Iron Poisoning
• Stage 3:
– Circulatory collapse : 48-96 hrs
• Metabolic acidosis, hypotension, low Cardiac
output.
• Coagulopathy
• Multiorgan system failure
Iron Poisoning
• Stage 4:
– Hepatic failure: 96 hrs
• Increased mortality
• Rarely fulminant hepatic failure
• Hepatic necrosis
– Liver transplant can save lives
Iron Poisoning
• STAGE 5:
– Bowel obstruction 2-6 wks
– Due to scarring
• Gastric outlet obstruction
• Small intestinal obstruction
– May not pass through stage 4
Iron Poisoning
Management:
1. Gastric decontamination:
• Forced emesis
• Gastric lavage with 5% NaHCO3
• No activated char coal
2. Secure good IV
3. Get initial the 4hrs levels and TBC
4. Chelate with Deferoxamine if levels>
300mg/dL
Iron Poisoning
• Chelate with Deferoxamine:
– Stable pts : levels< 500 mg/dL 40mg/kg
IM/IV
– Unstable: bleeding/ level > 500
• Give 20cc/kg NS/RL
• Deferoxamine at 15 mg/kg IV over 1hr
• Continuous drip at 15mg/kg/hr
• Continue till “vin rose” urine color disappears.
Iron Poisoning
• Observe for:
– Systemic BP
– ECG
– CVP
• Signs of hepatic failure:
–
–
–
–
Bleeding
Glucose intolerance
Hyperammonemia
Encepalopathy
SALICYLATES
• Oral ingestion commonest
• Transdermal less
• Peak levels at 12 hrs
– Early : hyperpnea  respiratory alkalosis
– Then metabolic acidosis
– Severe cases: Cerebral edema and increased
ICP
SALICYLATES
• MANAGEMENT
– Treat electrolyte imbalance
– IV hydration
– Forced alkaline diuresis
– Hemodialysis
– Diuretics
Hydrocarbons
• Kerosene ingestion:
–
–
–
–
–
Risk of aspiration
GIT & Respiratory effects.
Burning sensation, nausea, belching and diarrhea
Cough, chocking, gagging and grunting.
CXR 2-8 hrs later: Pulmonary infiltrates or perihilar
densities.
– pneumatoceles, pleural effusion or pneumothorax and
bacterial superinfection
– Resolution 2-7 days.
Hydrocarbons
• Treatment:
– Do not induce vomiting
– Do not attempt gastric lavage
– Risk of aspiration outweighs any benefit from
removal of substance
– CXR around 2-4 hrs “not before 2hrs”
– Observe in ER for 6-8 hrs if no symptoms 
discharge.
Poisoning in Children
“Prevention is the vaccine for the disease of
injury.”
• Host
• AGENT
• Environment
A causal
relationship!
Poisoning in Children
“Prevention is the vaccine for the disease of
injury.”
• Host
• AGENT
• Environment
A causal
relationship!
Poisoning in Children
Prevention
• The reduction in the incidence of childhood poisonings in the past
half-century has been dramatic.
• This reduction is largely the result of the combination of highly
effective active and passive methods of intervention.
– Passive interventions eg: introduction of child-resistant containers for
drugs and other dangerous household products. Child-resistant
containers have been particularly effective in reducing the incidence of
death from the ingestion of prescription drugs by children.
– Active interventions, which require a change in behavior by parents and
caretakers, include the safe storage of household products.
Thank you
Norah Khathlan M.D.