Summary of "Chp 22 Toxicology"
Summary of Chapter 22: Toxicology
This chapter provides a comprehensive overview of toxicology, focusing on the recognition, assessment, and management of various poisonings encountered in emergency medical services (EMS). It covers the types of poisons, routes of exposure, signs and symptoms, treatment protocols, and special considerations for different toxic agents including carbon monoxide, nerve agents, drugs, and environmental toxins.
Main Ideas and Concepts
Definition and Scope of Toxicology
- Toxicology is the study of poisonous substances and their effects on the body.
- A poison is any substance that can damage body structures or impair function.
- A toxin is a poison produced by living organisms (bacteria, plants, animals).
- Substance abuse involves misuse of substances to achieve a desired effect; overdose is excessive intake.
Types of Poisoning
- Inhaled
- Ingested
- Injected
- Absorbed (through skin or mucous membranes)
- Alcohol intoxication and withdrawal
Epidemiology
- Acute poisoning affects over 2 million people annually.
- Poisoning deaths are rare but more common in adults due to drug abuse.
- Child poisonings have decreased due to safety measures like child-resistant packaging.
Routes of Poison Entry and Corresponding Management
- Inhalation: Remove patient from exposure, provide oxygen, consider hazmat team for toxic gases, decontaminate if needed.
- Absorption: Remove contaminated clothing, brush off dry chemicals before flushing with copious water, irrigate eyes carefully (both eyes simultaneously if both exposed).
- Ingestion: Assess for burns, GI symptoms, seizures; activated charcoal may be administered if protocol allows; contact poison control.
- Injection: Usually from bites, stings, or drug use; cannot remove poison; treat symptomatically and transport.
Assessment and History Taking
- Scene safety and BSI (body substance isolation) are paramount.
- Observe for clues: odors, containers, medications, patient behavior.
- Ask key questions:
- What was taken?
- When?
- How much?
- Any interventions performed?
- Weight of patient?
- Collect and bring any suspicious materials or vomitus for analysis.
Signs and Symptoms by Poison Type
- Opioids: Respiratory depression, pinpoint pupils, sedation, hypotension.
- Stimulants (cocaine, methamphetamine): Hypertension, tachycardia, dilated pupils, agitation, hyperthermia.
- Sedatives (benzodiazepines, barbiturates): Slurred speech, drowsiness.
-
Anticholinergics (e.g., atropine, diphenhydramine): Hot, dry skin, dilated pupils, agitation
Mnemonic: “Hot as a hare, blind as a bat, dry as a bone, red as a beet.”
-
Cholinergics (organophosphates, nerve agents): Excess secretions (salivation, lacrimation, urination, defecation, gastric upset, emesis, muscle twitching, pinpoint pupils)
Mnemonics: SLUDGE or DUMBELS.
-
Alcohol: CNS depressant causing slowed reflexes, impaired judgment, possible delirium tremens in withdrawal.
- Inhalants: Heart sensitization, CNS depression, risk of sudden death.
- Hydrogen sulfide: Toxic gas causing respiratory and CNS depression, distinctive rotten egg odor.
Treatment Protocols
- Ensure scene safety and use PPE.
- Remove contaminated clothing and flush skin with water (brush off dry chemicals first).
- Provide oxygen and support airway, breathing, and circulation (ABCs).
- Use activated charcoal when appropriate (1 g/kg body weight), mixed with a flavored soda to improve palatability; contraindicated in certain poisonings (alkalis, cyanide, ethanol, iron, lithium, methanol, acids, solvents).
- Monitor vital signs frequently (every 5 minutes if unstable, every 15 if stable).
- Contact poison control center (1-800-222-1222) and medical control for guidance.
- Transport promptly to hospital.
- Use naloxone (Narcan) for opioid overdoses via intranasal, IV, or IM routes.
- Calm and reassure patients; avoid restraints unless necessary for safety.
- Document thoroughly, including time of exposure, substances involved, treatments given, and patient response.
- Bring any Material Safety Data Sheets (MSDS) from industrial or chemical exposures to hospital.
Special Considerations
- Children are more prone to accidental ingestions; adults more often deliberate overdoses.
- Drug tolerance and addiction require increasing doses for the same effect, complicating treatment.
- Be aware of potential infectious risks from drug use (HIV, hepatitis, tuberculosis).
- Food poisoning caused by bacteria (e.g., Salmonella, Listeria), toxins (e.g., botulism), or viruses; proper food handling and cooking prevent many cases.
- Plant poisonings are common but diverse; do not try to memorize all—use poison control.
- Be cautious with synthetic drugs such as bath salts, synthetic marijuana (spice), and hallucinogens; they can cause severe agitation, hallucinations, and medical emergencies.
Common Mnemonics
-
SLUDGE (Cholinergic poisoning): Salivation, Lacrimation, Urination, Defecation, Gastric upset, Emesis.
-
DUMBELS (Cholinergic poisoning): Diarrhea, Urination, Miosis, Bradycardia, Emesis, Lacrimation, Salivation.
-
Anticholinergic toxidrome: Hot as a hare, blind as a bat, dry as a bone, red as a beet, mad as a hatter.
Detailed Methodology / Instructions for EMS Responders
Scene Safety and Initial Actions
- Ensure scene is safe before approaching patient.
- Use appropriate PPE to avoid contamination.
- Assess number of patients to identify possible environmental exposures.
Patient Assessment
- General impression and ABCs (Airway, Breathing, Circulation).
- Look for signs of poisoning (pupils, skin, respiratory status).
- Obtain SAMPLE history focusing on:
- Substance involved
- Time and amount of exposure
- Route of exposure
- Interventions already performed
- Patient weight (for dosing activated charcoal)
- Check environment for clues (containers, odors, medications).
Management of Specific Exposure Routes
- Inhalation: Remove from source, provide oxygen, consider hazmat team for decontamination.
- Absorption: Remove contaminated clothing, brush off dry chemicals, flush with water for 15–20 minutes.
- Ingestion: Assess for burns, GI symptoms; consider activated charcoal if indicated; do not induce vomiting unless directed by poison control.
- Injection: Supportive care, remove constricting jewelry, calm patient, rapid transport.
Activated Charcoal Administration
- Confirm protocol allows use.
- Dose: 1 gram per kilogram of body weight.
- Mix with flavored soda (e.g., Sprite) and administer via straw.
- Obtain medical control approval.
- Document administration time and patient response.
- Watch for side effects: nausea, vomiting, black stools.
Use of Antidotes
- Naloxone for opioid overdose (intranasal preferred).
- Atropine and pralidoxime (2-PAM) for organophosphate poisoning (military antidote kits).
Decontamination Procedures
- Remove contaminated clothing.
- Brush off dry chemicals before flushing.
- Flush with large amounts of water (15–20 minutes).
- Use eye wash stations or improvised methods for ocular exposure.
- Coordinate with hazmat teams as needed.
Transport and Documentation
- Transport to nearest appropriate facility.
- Provide detailed report including history, signs, symptoms, treatments, and environmental findings.
- Bring any physical evidence (containers, vomitus, MSDS sheets) to hospital.
Important Resources and Contacts
- Poison Control Center: 1-800-222-1222
- Material Safety Data Sheets (MSDS): Obtain from industrial sites or product packaging for chemical exposures.
- Medical Control: Always consult for treatment decisions and antidote administration.
Key Takeaways
- Poisonings can occur through multiple routes and require rapid identification and management.
- Scene safety and personal protection are critical to prevent secondary contamination.
- History taking and environmental assessment guide treatment decisions.
- Activated charcoal is a valuable tool but has limitations and contraindications.
- Specific antidotes exist for some poisonings (e.g., naloxone, atropine).
- Poison control centers are essential partners in managing poisonings.
- Alcohol, opioids, stimulants, and synthetic drugs present common and complex toxicological challenges.
- EMS providers must be prepared to manage acute poisonings, support ABCs, and transport patients safely.
Speakers / Sources Featured
- Primary Speaker: An EMS educator or instructor providing a detailed lecture on toxicology (name not specified).
- References to National Education Standards and Poison Control Center protocols.
- Mention of Military antidote kits (atropine and pralidoxime) for nerve agent poisoning.
- Anecdotal references to personal EMS and law enforcement experience by the speaker.
- Use of mnemonics and clinical tables (e.g., Table 22-1) for teaching purposes.
This summary encapsulates the key points, clinical guidelines, and practical instructions from the chapter on toxicology as presented in the video subtitles.
Category
Educational
Share this summary
Is the summary off?
If you think the summary is inaccurate, you can reprocess it with the latest model.
Preparing reprocess...