Chapter 22: Toxicology

Toxicology

study of toxic or poisonous substances

Your primary responsibility to the patient who has been poisoned is

to recognize that a poisoning has occurred.

If you suspect that ingestion or exposure to a toxic substance has occurred,

notify medical control and begin emergency treatment at once.

If possible, while obtaining the SAMPLE history, ask the patient:

a. What substance did you take?

b. When did you take it (or become exposed to it)?

c. How much did you ingest?

d. Did you have anything to eat or drink before or after you took it?

e. Has anyone given you an antidote or any substance orally since you ingested it?

f.How much do you weigh?

The four routes to consider are:

a. Inhalation

b. Absorption (surface contact)

c. Ingestion

d. Injection

2. All four routes of poisoning can lead to life-threatening conditions.

B. Inhaled poisons

1. Move the patient into fresh air immediately.

2.The patient may require supplemental oxygen.

Leaving a car engine running in an enclosed garage can cause

carbon monoxide poisoning

Absorbed and surface contact poisons Can affect the patient in many ways.

a. Skin, mucous membrane, or eye damage

b. Chemical burns

c. Rashes or lesions

d.Systemic effects

Signs and symptoms for absorbed poisoning

a. A history of exposure

b. Liquid or powder on a patient’s skin

c. Burns

d. Itching

e. Irritation

f. Redness of the skin

g.Typical odors of the substance

Emergency treatment for a typical contact poisoning includes:

a. Avoid contaminating yourself or others.

b. While protecting yourself, remove the substance from the patient as rapidly as possible.

c. Remove all contaminated clothing.

If dry powder has been spilled,

brush off the powder, then flood the area with water for 15 to 20 minutes, then wash skin with soap and water.

If liquid has been spilled onto the skin

flood for 15 to 20 minutes.

If a chemical agent is introduced to the eyes,

irrigate them quickly and thoroughly.

80% of poisoning is by

mouth

Signs and symptoms for ingested poisons:

burns around the mouth, gastrointestinal pain, vomiting, cardiac dysrhythmias, and seizures.

Injected Poisons Signs and symptoms include:

a. Weakness

b. Dizziness

c. Fever

d. Chills

e. Unresponsiveness

f.Excitability

if swelling occurs

remove rings, watches, and bracelets from area

Treatment focuses on support.

1. Assess and maintain the patient’s XABCs.

2.Treat for shock, if necessary, and transport the patient promptly to the nearest appropriate hospital.

Activated charcoal binds to

specific toxins and prevents their absorption by the body; the toxins are then carried out of the body in the stool.

Activated charcoal is not indicated for patients:

a. Who have ingested alkali poisons, cyanide, ethanol, iron, lithium, methanol, mineral acids, or organic solvents

b.Who have a decreased level of consciousness and cannot protect their airway

The importance of safety awareness and standard precautions in caring for victims of drug abuse cannot be overemphasized.

Known drug abusers have a fairly high incidence of serious and undiagnosed infections, including HIV and hepatitis.

a.Expect the unexpected and remember: the drug user, not the drug, can pose the greatest threat.

Alcohol is a powerful

CNS depressant.

•  dulls the sense of awareness, slows reflexes, and reduces reaction time.

• who appears intoxicated may have other medical problems as well.

If a patient exhibits signs of serious CNS depression,

provide respiratory support.

Patients in alcohol withdrawal may experience

frightening hallucinations or delirium tremens (DTs).

Alcohol treatment

• Provide prompt transport.

• Reassure the patient and provide necessary care and emotional support.

Narcotic

drug that produces sleep or altered mental consciousness.

Opiods

type of narcotic to relieve pain

• is a CNS depressant —> cause respiratory depression and cardiac arrest.

Symptoms of Opiods

Patients typically appear sedated or unconscious and cyanotic with pinpoint pupils.

Narcan reverses the effects of

opiate or opiod overdose

• can be given intravenously, intramuscularly, or intranasally.

• Should only be given if agonal respirations present or is apneic

Sedative-Hypnotic drugs

•  CNS depressants and alter the level of consciousness.

•  agents are taken by mouth.

• your treatment is to ensure airway is patent, assist ventilations, and provide prompt transport.

Abused inhalants

•  agents are inhaled instead of ingested or injected.

• Found in glues, cleaning compound, paint thinners, and lacquers

• Effects of inhalants range from mild drowsiness to coma, and often cause seizures.

• Treatment:

  • Try to keep such patients from struggling with you or exerting themselves.

  • Use a stretcher to move the patient, give oxygen, and transport the patient to the hospital.

Hydrogen sulfide

•  toxic, colorless, and flammable gas with a distinctive rotten-egg odor.

• most impact on the lungs and CNS.

• Signs and symptoms include nausea and vomiting, confusion, dyspnea, a loss of consciousness, seizures, shock, coma, and cardiopulmonary arrest.

• Treatment:

  • a. Monitor and assist the patient’s respiratory and cardiovascular functions.

    b.Provide rapid transport.

Sympathomimetics

• cause hypertension, tachycardia, and dilated pupils.

• produces excited states

Examples of Sympathomimetics include

amphetamines, methamphetamines, phentermine hydrochloride, amphetamine sulfate (Benzedrine), and designer drugs, such as MDMA (ecstasy).

Cocaine can be absorbed through mucous membranes or

even across skin

• results in excitement —> smocked cocaine is the most rapid absorption

• Treatment

  • prompt transport and give supplemental oxygen, use potential suctioning

Synthetic cathinones (bath salts)

Produce euphoria, increased mental clarity, and sexual arousal.

a. Most users of this drug snort or insufflate the powder nasally.

b. Effects reportedly last as long as 48 hours.

4. Adverse effects include teeth grinding, appetite loss, muscle twitching, lip smacking, confusion, gastrointestinal conditions, paranoia, headache, elevated heart rate, and hallucinations.

5. Keep the patient calm and transport.

6. Consider ALS assistance; some of these patients may require chemical restraint to facilitate safe transport.

Marijuana

• Inhaling marijuana smoke produces euphoria, relaxation, and drowsiness.

• Impairs short-term memory and the capacity to do complex thinking and work.

“Edibles” or baked goods, candies, and other food additives that have

been infused with marijuana

Ingestion of marijuana can lead to cannabinoid hyperemesis syndrome, characterized by

chronic marijuana use and extreme nausea and vomiting that is relieved only by a hot shower or bath.

Treatment for Marijuana and hallucinogens

Care is the same as that for a patient who has taken a sympathomimetic.

a. Use a calm, professional manner.

b. Provide emotional support.

c. Do not use restraints unless you or the patient is in danger of injury.

d. Watch the patient carefully throughout transport, and do not leave unattended.

e. Request ALS assistance when appropriate.

Hallucinogens

• alter a person’s sensory perceptions.

• Patients experiencing a “bad trip” have:

  a. Hypertension

  b. Tachycardia

  c. Anxiety

  d.Paranoia

Anticholinergic agents

• Medications that have properties that block the parasympathetic nerve

• symptoms: hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter.”

  
  

Cholinergic agents

Overstimulate normal body functions that are controlled by the parasympathetic nerves.

Use the mnemonic DUMBELS to remember the signs and symptoms of cholinergic drug poisoning:

a. Diarrhea

b. Urination

c. Miosis (constriction of the pupils)

d. Bradycardia, bronchospasm, bronchorrhea (discharge of mucus from the lungs)

e. Emesis (vomiting)

f. Lacrimation (tearing)

g.Seizures, salivation, sweating

The most important consideration for cholinergic is to

avoid exposure yourself.

• a. Decontamination may take priority over immediate transport.

  i. In many jurisdictions, the hazmat team will provide decontamination and contain the exposure chemical.

  b. Your priorities after decontamination are to decrease the secretions in the mouth and trachea and provide airway support.

Treatment for cholinergic

Most common is the DuoDote Auto-Injector.