Poisoning
pathological state caused by a toxic agent
Poisoning Sources
- medications
- plants
- environmental sources
- pollutants
- drugs of abuse (benzodiazepine/opoioids)
Poisoning Entry
- oral
- inhalation
- injection
- absorption through skin
What do poisoning symptoms often mimic?
a disease
What should you always do first?
contact poison control
What are the fundamentals of treating poisoning?
- supportive care
- identification of poison
- prevention of further absorption
- poison removal
- antidotes/antivenin
What is the most important element in managing acute poisoning?
supportive care
What is supportive care based on?
- patient's clinical status
- requires no knowledge specific to poison involved
What are the primary concerns for supportive care?
- maintenance of respiration and circulation
- airway: oxygen
- volume: normal saline or Ringer's solution
- assess blood glucose
- assess acid-base status
- convulsions: IV benzodiazepines
Poison Identification
- knowing the identity and dosage of the toxicant facilitates treatment of poisoning
- histories taken at times of poisoning are often inaccurate
- gas chromatograph/mass spectrometer can provide qualitative and quantitative information
What are ways to prevent further absorption?
- activated charcoal
- gastric lavage and aspiration (stomach pump)
- whole-bowel irrigation (laxatives used before colonoscopies)
- surface decontamination (poisons that come into contact from clothes, etc.)
What do drugs used for poison removal do?
act by increasing renal excretion of toxic agents
What is necessary to tolerate these types of agents?
normal renal function (can still result in irreversible kidney damage)
Nonpharmacologic Methods of Poison Removal
- peritoneal dialysis
- hemodialysis
- exchange transfusion
- preferred
Antidotes
- antidotes can be extremely valuable
- antidotes are rare
- for most poisons, no specific antidote exists
- naloxone
- physostigmine
(Antidotes) Naloxone
- reverses poisoning by heroin and other opioids
- reverses effect of opioid by binding to new receptors in the brain
(Antidotes) Physostigmine
treatment of poisoning by atropine and other anticholinergic drugs
What is the preferred method for removing ingested poisons from the GI tract?
activated charcoal
(Activated Charcoal) When must it be given?
within 1 hour of ingestion
(Activated Charcoal) What is it not effective for?
- alkali poisoning
- cyanide
- ethanol
- iron
- lithium
- methanol
- mineral acids
- organic solvents
(Activated Charcoal) Who is it contraindicated in?
GI obstruction/ileus
(Activated Charcoal) Common Adverse Effects
- nausea
- vomiting
- constipation
- diarrhea
- black stool
(Activated Charcoal) How does it prevent toxicity?
absorption of poisons onto charcoal
(Activated Charcoal) Should antidotes be administered immediately before, with, or after the charcoal?
No
(Gastric Lavage (Irrigation) and Aspiration) What is this?
involves flushing the stomach with fluid and then aspirating the fluid back out
(Gastric Lavage (Irrigation) and Aspiration) What is it used in?
- life-threatening cases
- if less than 60 minutes has elapsed since poison ingestion
(Gastric Lavage (Irrigation) and Aspiration) Contraindications
- hydrocarbons (aspiration
- corrosive substances (can be damaging if they get into the lungs)
- risk of GI bleed or perforation if recent surgery
(Whole-Bowel Irrigation) Agents
- CoLyte
- GoLYTELY
(Whole-Bowel Irrigation) What is it effective against?
- opium
- lithium
- lead
- sustained-release products
(Whole-Bowel Irrigation) What is the most common accidental poisoning in children?
iron
(Whole-Bowel Irrigation) How is it given?
- tube
- enters the body very quickly
(Whole-Bowel Irrigation) Contraindications
GI tract issues
(Surface Decontamination) What can topical exposure to toxicants cause?
local and systemic injury
(Surface Decontamination) What should be done?
- remove contaminated clothing
- wash poison from victim
- alternate soa-and-water washes with alcohol washes
- personnel performing these washes should take precautions to avoid contaminating themselves
- flush eyes with water for at least 15 minutes
- u
What is a drug that is used to remove poison?
sodium bicarbonate
Sodium Bicarbonate
- enhances renal excretion
- need healthy kidney function
What are some non drug methods of poison removal?
- hemodialysis
- hemoperfusion
Hemodialysis
more commonly used to directly remove poison from the bloodstream
Hemoperfusion
exchange transfusion
(Acetylcysteine) What is this used for?
acetaminophen overdose
(Acetylcysteine) How is it given?
- oral/IV
- often given orally to prevent anaphylaxis
(Acetylcysteine) When must it be administered?
within 24 hours of ingestion
(Acetylcysteine) If it cannot be given with 24 hours, what is the only option?
liver transplant
(Acetylcysteine) When does the person not feel ill until?
liver damage starts
(Acetylcysteine) Dosage
140 mg/kl x 1 then 4 hours later 70 mg/kg every 4 hours x17 doses
(Acetylcysteine) Common Adverse Reactions
- anaphylaxis (IV use)
- nausea
- vomiting
- hives
- rash
(Acetylcysteine) What can it be used in nebulized form for?
- cough
- COPD
What are the most common metal poisonings?
- iron
- lead
- mercury
- arsenic
- gold
- copper
What are heavy metal poison antidotes called?
chelating agents or chelators
(Deferoxamine (Desterol)) What is this used for?
iron toxicity
(Deferoxamine (Desterol)) How is it given?
IM
(Deferoxamine (Desterol)) When must it be administered?
in under 48 hours
(Deferoxamine (Desterol)) Common Adverse Reactions
- ARDS
- high renal excretion (can cause stress on the kidneys)
- use short-term
Deferasirox (Exjade)
iron toxicity
(Dimercaprol (BAL in oil)) What is it used for?
- arsenic
- gold
- mercury
- lead
(Dimercaprol (BAL in oil)) How is it given?
IM
(Dimercaprol (BAL in oil)) Common Adverse Reaction
hypertension
(Edetate Calcium Disodium (EDIA)) What is it used for?
lead poisoning
(Edetate Calcium Disodium (EDIA)) Black Box Warning
- toxic encephalopathy (increases ICP)
- nephrotoxic
(Edetate Calcium Disodium (EDIA)) How is it given?
- IM
- IV
Penicillamine (Depen)
chelates with cooper, iron, lead, arsenic, gold, and mercury
(Succimer (Chemet)) What does it bind avidly to?
- lead
- mercury
- arsenic
(Succimer (Chemet)) What does it bind less avidly with?
- copper
- zinc
(Succimer (Chemet)) What does it have minimal binding with?
- iron
- calcium
- magnesium
(Succimer (Chemet)) Adverse Reaction
neutropenia
(Succimer (Chemet)) How is it given?
orally
(Fomepizole (Antizole)) What it used for?
ethylene glycol, the principal component of antifreeze
(Fomepizole (Antizole)) How is it given?
IV
BIOTERRORISM
...
Potential Weapons of Terrorism
- bacteria
- viruses
- biotoxins
- chemical weapons (nerve agents and mustard gas)
- radiologic weapons
(Anthrax) Bacillus anthracis
aerobic gram-positive bacterium
(Anthrax) How long is the dormant form viable for?
decades
(Anthrax) How does it enter the body?
- inhalational
- cutaneous
- gastrointestinal
(Anthrax) Where does it enter the body?
- skin
- mucous membranes of the respiratory tract
(Anthrax) Is it transmitted person to person?
No
(Anthrax) Mortality Rate
high
(Anthrax) Treatment
- doxycycline
- antibiotics
- vaccine (military/vets/lab workers)
(Inhalational Anthrax) Where do anthrax spores deposit?
alveolar space
(Inhalational Anthrax) Mortality Rate
- can be high even with treatment (80% or higher)
- the form with the highest mortality
(Inhalational Anthrax) Clinical Latency
2 days to 4 weeks
(Inhalational Anthrax) What do mature bacilli release?
toxins
What does this cause?
- hemorrhage
- edema
- necrosis
(Inhalational Anthrax) What happens if toxins reach critical level?
antibiotics cannot prevent death
(Inhalational Anthrax) Initial Symptoms
- fever
- cough
- malaise
- weakness
(Inhalational Anthrax) Second Stage
- 2 to 3 days later
- sudden increase in fever
- severe respiratory distress
- septicemia
- hemorrhagic meningitis
- shock
(Cutaneous Anthrax) When do symptoms appear?
1 to 7 days after exposure to spores
(Cutaneous Anthrax) What is most vulnerable?
broken skin
(Cutaneous Anthrax) Where can injuries develop?
anywhere spores land
(Cutaneous Anthrax) Initial Lesion
small pupil or vesicle associated with local itching
(Cutaneous Anthrax) Lesion (2 Days)
lesion enlarges into painless ulcer with necrotic core
(Cutaneous Anthrax) Lesion (7-10 days after symptoms develop)
black eschar forms, then dries, loosens, and sloughs off by days 12 to 14
(Cutaneous Anthrax) What happens to lesions in most cases?
resolve without complications or scarring
(Cutaneous Anthrax) Mortality
- treatment is usually successful
- 20% die without antibiotic treatment
(Anthrax) Respiratory Treatment
- IV ciprofloxacin
- IV doxycycline
- raxibacumab
- obiltoxaximab
(Anthrax) Cutaneous Treatment
- oral ciprofloxacin
- oral doxycycline
(Anthrax) BioThrax
- pre-exposure vaccination
- licensed for use in the United States
- inactivated cell-free preparation
(Anthrax) BioThrax Dosage
- 3 subQ injections 2 weeks apart, then at 6, 12, and 18 months
- annual boosters recommended
(Anthrax) Who should be vaccinated with BioThrax?
- military personell
- those who handle animal products from anthrax-endemic areas, including veterinarians, laboratory workers, and others
(Anthrax) Postexposure Prophylaxis
- oral antibiotics + anthrax vaccine
- antibiotics if thought to be exposed
- vaccine if exposure is confirmed
- vaccine at 0, 2, and 4 weeks
Francisella Tularenesis
- tularemia
- rabbit fever
- deer fly fever
- potentially fatal
(Francisella Tularenesis) Why is it difficult to diagnose?
acute symptoms are similar to the flu
(Francisella Tularenesis) What does it affect?
- skin
- mucous membranes
- GI tract
- lungs
(Francisella Tularenesis) What can develop?
- pneumonia
- pleuritis
(Francisella Tularenesis) Treatment
- IM streptomycin
- IM gentamicin
(Francisella Tularenesis) How should a mass outbreak and prophylaxis be treated?
- oral doxycycline
- ciprofloxacin
Yersinia Pestis
- gram-negative bacillus
- plague
(Yersinia Pestis) What are the 2 forms?
1.) bubonic
2.) pneumonic
(Yersinia Pestis) Bubonic
- tender, enlarged, inflamed lymph nodes
- rarely develops into pneumonic plague
- much more manageable
(Yersinia Pestis) Is the bubonic plague transmitted person to person?
No
(Yersinia Pestis) Pneumonic
- inflammation of the lungs
- acquiring by inhaling aerosolized Y. pestis
(Yersinia Pestis) How is pneumonic transmitted?
person to person (by cough)
(Yersinia Pestis) What will pneumonic progress to without treatment?
- respiratory failure
- death
(Yersinia Pestis) Pneumonic Treatment
- streptomycin (IM)
- gentamicin (IM or IV)
(Yersinia Pestis) How is pneumonic treated in a mass casualty event?
- oral doxycycline
- ciprofloxacin
Variola Virus
- smallpox
- viral
(Smallpox) Contagious Rate
high
(Smallpox) Fatality Rate
30%
(Smallpox) Treatment
- no proven treatment
- supportive
- antivirals only used for secondary infection
(Smallpox) What does it cause?
significant lesions
(Smallpox) Antivirals
- cidofovir
- adefevir
- ribavirin
(Smallpox) Topical Idoxuridine
corneal lesions
(Smallpox) What are antibiotics used to treat?
secondary bacterial infections
(Smallpox Vaccine) Duration of Protection
booster every 3 years if high risk
(Smallpox Vaccine) Administration
1 drop percutaneously via 15 bifurcated needle jabs
(Smallpox Vaccine) Response
- goal is to elicit a specific skin response
- about 3 weeks after the vaccine, you should have a scar
- if there is no response, you might get immunized again
(Smallpox Vaccine) Is this vaccine a relatively safe vaccine?
No
(Smallpox Vaccine) What type of vaccine is it?
live virus
(Smallpox Vaccine) Should it be given to pregnant women?
No
(Smallpox Vaccine) Mild Adverse Effects
- local inflammation
- swelling
- tenderness in regional lymph nodes
- transient symptoms (fever, headaches, muscle aches, fatigue)
(Smallpox Vaccine) Moderate to Severe Adverse Effects
- eczema vaccinatum
- generalized vaccinia
- progressive vaccinia
- postvaccinal encephalitis
- fetal vaccinia
- possible cardiac effects (myocarditis, pericarditis)
(Smallpox Vaccine) Management of Adverse Effects
- vaccinia immune globulin (VIG)
- cidofovir (vistide)
(Smallpox Vaccine) Who should not be vaccinated?
- people with eczema, atopic dermatitis, or immunodeficiency
- pregnant patients
- people living with someone for whom vaccine is contraindicated
Botulinum Toxin
- biotoxin
- Clostridium botulinum
(Botulinum Toxin) What does it do?
blocks the release of acetylcholine from cholinergic neurons
(Botulinum Toxin) What happens without treatment?
- paralysis
- respiratory failure
- death
- diaphragm becomes paralyzed
(Botulinum Toxin) Classic Symptoms
- double vision
- blurred vision
- drooping eyelids
- slurred speech
- dry mouth
- dysphagia
- muscle weakness
- descending flaccid paralysis (starts from the head and goes down)
(Botulinum Toxin) Treatment
- prolonged supportive care
a. fluid/nutrition support
b. mechanical ventilation
- immediate infusion of botulinum antitoxin and/or botulism immune globulin (BIG)
- no vaccine
(Botulinum Toxin) BabyBIG
new immunoglobulin formulation for treating children younger than 1 year
(Botulinum Toxin) How can babies be exposed?
raw honey
(Ricin) Where is ricin found?
- castor beans
- extraction from the "mash" when beans are processed to make castor oil
- powder, pellet, mist, or dissolved in water or a weak acid
(Ricin) What does ricin do?
inhibits protein synthesis
(Ricin) Treatment
- purely supportive
- no antidote
- vaccine in development
(Ricin) Mortality Rate
mostly fatal
(Ricin) Inhalation Clinical Manifestions
in a few hours:
- coughing
- chest tightness
- difficulty breathing
- nausea
- muscle aches
later:
- severely inflamed/edamtour airway
- cyanosis and death can follow
(Ricin) Ingestion Clinical Manifestations
- intestinal and gastric hemorrhage
- vomiting
- diarrhea
- liver, spleen, kidneys may fail
- death within 10 to 12 days of ingestion
(Ricin) Injection Clinical Manifestations
- severe symptoms and death
- impractical route for terrorism
What are some examples of chemical weapons?
- nerve agents
- sulfur mustard (mustard gas)
(Nerve Agents) What do nerve agents do?
produce a state of cholinergic crisis characterized by excessive muscarinic stimulating and depolarizing neuromuscular blockade
(Nerve Agents) Where do they tend to get on?
skin (get clothes off and wash skin, can cause severe burns)
(Nerve Agents) Treatment
- mechanical ventilation
- atropine
- pralisoxime
- diazepam
(Mustard Gas) What is mustard gas?
- alkylating agent and vesicant
- can be vaporized into air or released into water supply
- during World I: killed less than 5% of victims
(Mustard Gas) Mortality Rate
- injuries severe
- fatalities low
(Mustard Gas) What do symptoms of toxicity depend on?
- dose
- tissue involved
- duration of exposure
(Mustard Gas) Treatment
- rapid decontamination
- supportive care
- drug therapy
Examples of Radiologic Weapons
- nuclear bomb
- nuclear power plant attack
- dirty bomb (radiologic dispersion devices)
(Radiologic Weapons) Nuclear Bombs
immediate and delayed impact
(Radiologic Weapons) Nuclear Power Plant Attack
radiation exposure in area
(Radiologic Weapons) Dirty Bomb
radioactive material formulated into powder or pellets
(Radiologic Weapons) What drugs are used for radiation emergencies?
- potassium iodide
- pentetate zinc trisodium (Zn-DTPA) and pentetate calcium trisodium (Ca-DTPA)
- prussian blue (Radiogardase)
(Radiologic Weapons) Potassium Iodide
prompt treatment necessary
(Radiologic Weapons) Pentetate Zinc Trisodium (Zn-DTPA) and Pentetate Calcium Trisodium (Ca-DTPA)
treatment within 24 hours is most effective