Transcript
Chapter 27 Toxicology
Unit Summary
Upon completion of this chapter and related course assignments, students will understand how to recognize and manage common toxicological emergencies. They will be able to discuss the pathophysiology, psychosocial impact, presentation, prognosis, and management of various toxidromes and poisonings. Students will be able to identify the main types of poison, identify classes of compounds involved in substance abuse and poisonings as well as routes by which they enter the body, and their effects. They will be able to describe the assessment and management of the patient with a suspected poisoning or toxicological emergency, including common signs and symptoms. Students will be able to discuss substance abuse and identify common substances that are abused. They will understand the role of airway management in the patient suspected of poisoning or overdose. Students will be able to recognize how and when it is appropriate to contact a poison control center. They will be able to describe the routes of entry for toxic substances into the body and how to protect themselves from exposure to hazardous chemicals including when and how to appropriately decontaminate the patient prior to treatment. Students will be able to demonstrate the steps in the assessment and management of the patient with both suspected poisoning or overdose.
National EMS Education Standard Competencies
Medicine
Integrates assessment findings with principles of epidemiology and pathophysiology to formulate a field impression and implement a comprehensive treatment/disposition plan for a patient with a medical complaint.
Toxicology
Recognition and management of
• Carbon monoxide poisoning (pp 1344-1345)
• Nerve agent poisoning (p 1344)
• How and when to contact a poison control center (p 1326)
Anatomy, physiology, pathophysiology, assessment, and management of
• Inhaled poisons (pp 1327-1328, 1337-1338, 1344-1347)
• Ingested poisons (pp 1327, 1333-1347)
• Injected poisons (pp 1328, 1336-1337)
• Absorbed poisons (pp 1328, 1344-1348)
• Alcohol intoxication and withdrawal (pp 1333-1336)
• Opiate toxidrome (pp 1341-1342)
Anatomy, physiology, epidemiology, pathophysiology, psychosocial impact, presentations, prognosis, and management of the following toxidromes and poisonings:
• Cholinergics (pp 1329, 1344)
• Anticholinergics (pp 1329, 1353)
• Sympathomimetics (pp 1329, 1336-1340)
• Sedative/hypnotics (pp 1329, 1340-1341)
• Opiates (pp 1329, 1341-1342)
• Alcohol intoxication and withdrawal (pp 1333-1336)
• Over-the-counter and prescription medications ( pp 1355-1356)
• Carbon monoxide (pp 1344-1345)
• Illegal drugs (pp 1336-1339)
• Herbal preparations (p 1361)
Knowledge Objectives
Define toxicology, poison, and overdose. (pp 1325-1326)
Describe routes of entry of toxic substances into the body, including ingestion, inhalation, injection, and absorption. (pp 1327-1328)
Discuss major toxidromes and their use in assessment and management of toxicologic emergencies. (pp 1328-1329)
Identify the common signs and symptoms of poisoning. (pp 1329- 1330)
Describe the assessment and management of the patient with suspected poisoning. (pp 1344-1348, 1349-1353, 1357-1361)
Describe the assessment and management of the patient with suspected overdose. (pp 1331-1344, 1348-1349, 1353-1357)
Understand the role of airway management in the patient with suspected poisoning or overdose. (p 1331)
Discuss substance abuse and concepts associated with it. (pp 1329-1331)
Discuss emergencies related to severe intoxication, including alcoholism. (pp 1333-1361)
Explain the use of activated charcoal, including indications, contraindications, and the need to obtain approval from medical control before its administration. (pp 1341, 1348, 1350, 1353, 1354)
Identify the main types of specific poisons and their effects, including alcohol, stimulants, marijuana, hallucinogens, sedative-hypnotic drugs, narcotics (opiates and opioids), cardiac medications, organophosphates, carbon monoxide, chlorine gas, cyanide, caustics, drugs abused for sexual purposes, poisonous alcohols, hydrocarbons, psychiatric medications, nonprescription pain medications, theophylline, and metals and metalloids. (pp 1333-1358)
Describe the assessment and management of the patient with suspected plant or mushroom poisoning. (pp 1339-1340, 1358-1361)
Describe the assessment and management of the patient with suspected food poisoning. (p 1361)
Skills Objectives
Demonstrate the steps in the assessment and management of the patient with suspected poisoning. (pp 1331-1333)
Demonstrate the steps in the assessment and management of the patient with suspected overdose. (pp 1331-1333)
Readings and Preparation
• Review all instructional materials including Chapter 27 of Nancy Caroline’s Emergency Care in the Streets, Seventh Edition, and all related presentation support materials.
• Review local treatment protocols for care of patients with overdose and poisonings. Identify those that include activated charcoal administration.
• Identify the protocols that incorporate contacting poisoning control, and distribute the contact number to students.
• Review local protocols for patient decontamination and appropriate agencies that are responsible for setting up decontamination equipment.
• Meet with local hospital staff to identify decontamination locations and processes for patients who are not decontaminated prior to being admitted to the emergency department. Be prepared to share this information with your students.
• Review local protocols, and identify procedures for treatment and transport of substance abuse patients assessed as being unable to refuse and a risk to themselves or others.
Support Materials
• Lecture PowerPoint presentation
• Case Study PowerPoint presentation
• Be prepared to provide planning materials for chemical or poison exposure incidents for local agencies. Students should be familiar with guidelines regarding the decontamination and safe treatment and transport of the contaminated or exposure patient.
• Locate pictures of patients affected by chemical, toxicological, or poisonous exposures. They will be used in visual and practical exercises.
• Locate pictures of common street drugs to familiarize students with their appearance and enable them to recognize these substances at scenes.
• Locate pictures of poisonous plants common to your area as well as those used to produce illegal drugs so students can become familiar with these when assessing scenes where poisonous plants or illegal drug use may be suspected.
• Identify types of common chemicals used by local industry such as agriculture or industrial sites. Be prepared to share these with the class during the sections on these types of chemicals
Enhancements
• Direct students to visit the companion website to Nancy Caroline’s Emergency Care in the Streets, Seventh Edition, at http://www.paramedic.emszone.com for online activities.
• The Agency for Toxic Substances and Disease Registry website has extensive continuing education material for toxic exposures and can be offered for those students who desire more in-depth learning: http://www.atsdr.cdc.gov/csem/csem.html
• Contact a representative from the closest regional poison control center to provide literature and speak to the class about the services the center provides.
• Contact a local chapter for substance abuse support groups or a local substance abuse treatment facility. Arrange to have someone be a guest speaker to discuss signs and symptoms of the substance abuse patient, legal implications for transporting patients who are intoxicated, and psychosocial concerns when treating the substance abuse patient.
• Contact the local law enforcement agency to arrange a guest speaker to discuss common illicit substances seen in the community and prevalence of encounters with patients who overdose.
• Contact the local homeless shelter to identify someone as a guest speaker to discuss common poisoning, substance abuse, or toxicological emergencies seen in the homeless population.
• The Consumer Product Safety Comission’s Hazard Screening Report on Home and Family Maintenance Products: Household Chemicals provides a resource to compare the risks for different types of products, including information on injuries and deaths associated with those products: http://www.cpsc.gov/LIBRARY/hazard_householdchemicals.pdf
• Confined spaces can present health and safety hazards if they contain air contaminants. The CDC has a website that details the workplace health and safety hazards associated with confined space work, including atmospheric dangers: http://www.cdc.gov/niosh/topics/confinedspace/
Content connections: Toxicology emergencies may not be isolated incidents but may be a component of other emergencies such as industrial accidents, motor vehicle crashes, or farming incidents. Remind students to have an index of suspicion for this type of situation even if the initial mechanism of injury appears to be the result of trauma. Airway management and ventilatory support are common in the patient experiencing a toxicological or poisoning emergency. Be prepared to review airway management skills to refresh students on how to apply this in the toxicological or poisoning patient. With an increasing incidence of poisonings by prescription medications in children, students should be familiar with airway management and ventilatory support skills for the pediatric patient as well. Those patients who are suffering from substance abuse emergencies may also have preexisting psychiatric conditions. Remind students that they should be familiar with protocols for treatment and transport of patients determined to be a risk to themselves or others.
Cultural considerations: With increased incidence of grandparents raising grandchildren, there is a greater risk of unintentional poisonings and overdoses in the pediatric population on chronic prescription medications used to treat cardiovascular and other diseases. Students should be familiar with signs and symptoms of overdose for common medications taken by older patients and those with chronic health conditions. Some cultures use illegal substances as part of religious rituals and students, should be familiar with any population that they may encounter locally who engage in such practices. Toxic reactions are also possible due to exposure to commonly used items by specific subcultures such as athletes. Deadly accumulation of salicylates in the body can result form overuse of sports creams and linaments such as Icy Hot and Ben Gay. Drug and alcohol abuse is a common problem among teenagers today. Remind students that they should be concerned for the patient’s privacy and be nonjudgemental when assessing these patients.
Teaching Tips
• Encourage students to anonymously submit typed accounts of experiences they may have personally had with substance abuse or illicit drug use. Use discretion to ensure students are comfortable sharing information by having them submit it to you in a sealed envelope and unsigned. Students often have some type of experience that may allow a better comprehension of concerns when treating these patients if they are comfortable with sharing them.
• Review local protocols relevant to each section of the chapter dealing with poison control contact, identification of contaminated patients, decontamination processes for the covered toxidromes, dealing with combative or mentally incompetent patients as a result of substance abuse, and mandatory reporting of unsafe environments for children and elderly.
• Request a substance abuse counselor or nurse speak to the class about recognizing signs and symptoms of substance abuse or illicit drug use during that section of the chapter.
• Be prepared to share your findings about commonly abused illicit drugs, chemical incidents, and poisonings in your area during respective sections of the chapter.
• Review indications, contraindications, dosages, mechanisms of action, routes of administration, and side effects of activated charcoal and naloxone to refamiliarize students with the appropriate use of these medications.
Unit Activities
Writing activities: Assign students specific poisons or toxic substances to research and write a paper outlining how they are available, effects on the body’s systems, presentations of exposures, routes of exposure, management, and prognosis.
Student presentations: Assign students to prepare a presentation based on their topic from the writing activity. Have them present the information including any handouts available for prevention or awareness.
Group activities: Divide the class into groups of four to five students. Have them role play practical exercises of patients experiencing toxicological or poisoning emergencies for the class. Allow the class to observe the assessment, encouraging use of props for scene assessment, and then formulate a field diagnosis and treatment plan.
Visual thinking: Display the photographs of patients experiencing toxicological, chemical, or poisonous exposures, poisonous plants, and illicit substances. Have students move around the room to identify each in small groups.
Medical terminology: Have students make 10 flash cards independently with pertinent terminology for the subject matter. Divide the students into groups and have them swap cards to quiz one another on the terminology.
Pre-Lecture
You are the Medic
“You are the Medic” is a progressive case study that encourages critical-thinking skills.
Instructor Directions
Direct students to read the “You Are the Medic” scenario found throughout Chapter 27.
• You may wish to assign students to a partner or a group. Direct them to review the discussion questions at the end of the scenario and prepare a response to each question. Facilitate a class dialogue centered on the discussion questions and the Patient Care Report.
• You may also use this as an individual activity and ask students to turn in their comments on a separate piece of paper.
Lecture
I. Introduction
A. Paramedics are often called to treat patients who are abusing licit (legal) or illicit (illegal) drugs.
B. A poison is a substance that is toxic by nature, no matter how it gets into the body or how much is taken.
C. A drug is a substance that has some therapeutic effect when given in the appropriate circumstances and in the appropriate dose.
1. An “overdose” occurs when a drug is taken in excess.
2. Bioavailability: The extent to which any drug is present in sufficient amounts to produce a desired result
3. Half-life: The point when the bioavailability of a given drug has decreased to 50%
4. Excretion: How a drug is removed from the body
II. Types of Toxicologic Emergencies
A. Toxicologic emergencies usually fall in one of two categories.
1. Unintentional
a. Can occur in many ways, including:
i. Medication dosing errors
ii. Younger children who mistakenly put berries, medication, etc, in their mouths
iii. Hikers who come across poison ivy, wild mushrooms, etc
iv. Industrial hazards (polychlorinated biphenyls [PCBs], asbestosis, etc) that are not identified until after exposure
v. Neglect or oversight
2. Intentional
a. “Overdose” or “intimate crime”
i. Chloral hydrate and other pharmacologic agents are used to commit assault or homicide.
ii. “Date rape” drugs such as flunitrazepam (Rohypnol) have been used to commit sexual assault.
III. Poison Centers
A. Poison Centers (1-800-222-1222) may be an indispensable aid.
1. Can provide a rundown on a poison’s:
a. Ingestion
b. Toxic potential
c. Steps to negate effects
2. Never hesitate to call when confronted with any toxin for which you have limited or no familiarity.
a. When in doubt, call!
3. Your call helps the center collect data on poisonings in your region.
a. Trends
b. Developing public health problems
c. Current treatment protocols
IV. Anatomy and Physiology
A. Routes of absorption
1. Poisoning by ingestion
a. May produce immediate damage or delayed effects
i. Caustic substances cause immediate damage.
ii. Some poisons must be absorbed into the bloodstream before they can cause damage.
b. Most common sources:
i. Medication around the home
ii. Household chemicals
c. Marked by a wide range of possibilities
i. What is ingested?
ii. Why was it ingested?
(a) May be accidental or intentional
d. Assessment clues may include:
i. Stained fingers, lips, or tongues
ii. Sudden onset of stomach cramps with or without nausea, vomiting, diarrhea
iii. Empty pill bottles
e. Generally provides time for identification and treatment
i. Little absorption occurs in the stomach, and the substance may stay there for a while
ii. Management aims to remove or neutralize the poison before it gains access to the intestines.
2. Poisoning by inhalation
a. May occur when the toxic agent is present in the surrounding environment
i. Patient will continue to inhale the toxin as long as he/she remains in the environment.
(a) Paramedics who enter the environment will also inhale the toxin if not wearing the proper protective breathing apparatus.
ii. Likely to find more than one patient
b. May be accidental or intentional
i. Example: Carbon monoxide (CO) poisoning
(a) Painless method of suicide
(b) May occur from a faulty furnace
ii. A new suicide trend is to mix household chemicals inside an automobile with doors and windows shut.
(a) Toxic gases are created.
(b) May be colorless and odorless
(c) May place responders at risk of serious injury
c. Inhaled toxins reach the alveoli quickly, providing almost instant access to circulation.
i. Window of opportunity for problem identification and treatment is limited.
d. First general management consideration is scene safety.
i. Don proper breathing apparatus.
ii. Move patient to a safe environment before evaluation and treatment.
e. Wide range of signs and symptoms depending upon the toxin
i. Look for information at the scene to help identify toxin.
ii. Utilize the Poison Center and medical control.
f. Correction of hypoxia is a must.
i. Deliver oxygen and maintain saturation level in the 95% range.
ii. Establish vascular access.
iii. Apply ECG monitor.
iv. Perform pulse oximetry and capnography.
3. Poisoning by injection
a. Injected poisons usually gain access as the result of:
i. Stings or bites from insects and animals
ii. Abuse of intravenously administered drugs
(a) Heroin
(b) Cocaine
(c) Amphetamines
(d) “Speedballs” (heroin and cocaine together)
b. Possibilities for poisoning by injection vary by geographic location.
i. Snake bites and scorpion stings are prevalent in southwestern United States.
ii. Jellyfish, Portuguese man-of-war, sea urchin, and anemone stings are prevalent in coastal areas.
iii. Wasp, yellow jacket, and hornet stings are common throughout the United States.
c. Some injected poisons are neurotoxic, and others produce localized or systemic reactions.
i. When a bite or sting hits a vein or artery the toxin immediately enters the bloodstream.
(a) Outcome is more dangerous than when the same toxin enters a muscle mass
d. Physical findings will provide clues.
i. Especially local reactions
e. Signs and symptoms can vary greatly.
f. The patient may be able to identify the culprit.
4. Poisoning by absorption
a. Poisonings by pesticides are often the most serious.
B. Understanding and using toxidromes
1. Many drugs result in similar signs and symptoms.
2. Toxic syndrome or toxidrome: The syndromelike symptoms of a class or group of similar poisonous agents
a. Useful for remembering the assessment and management of different substances in the same group
3. Six major toxidromes exist:
a. Stimulants
b. Narcotics
c. Cholinergics
d. Anticholinergics
e. Sympathomimetics
f. Sedative/hypnotics
4. Often a working diagnosis can be developed by looking at:
a. History and physical findings
b. Vital signs
C. Overview of substance abuse
1. Highly challenging area of medicine because of:
a. Uncertainty about the prevalence of the problem
b. Continual evolution of the substances themselves
i. “Designer drugs” created in the 1980s
2. The definition of substance abuse differs among cultures.
a. May have little relation to the potential harm from the abused substance
3. Basic terms and concepts related to substance abuse include:
a. Drug abuse: Any use of drugs that causes physical, psychological, economic, legal, or social harm to the user or to others affected by the user’s behavior
b. Habituation: Psychological dependence on a drug or drugs
c. Physical dependence: A physiologic state of adaptation to a drug
i. Usually characterized by:
(a) Tolerance to the drug’s effects
(b) Withdrawal syndrome if the drug is stopped
d. Psychological dependence: The emotional state of craving a drug to maintain a feeling of well-being
e. Tolerance: Physiologic adaptation to the effects of a drug
i. Increasingly larger doses are required to achieve the same effect.
f. Withdrawal syndrome: Set of signs and symptoms that occurs after the abrupt cessation or dosage decrease of a drug
i. Usually involves altered central nervous system (CNS) activity
g. Drug addiction: A chronic disorder characterized by the compulsive use of a substance resulting in physical, psychological, or social harm to the user
h. Antagonist: Drug that has an affinity for a cell receptor
i. By binding to that receptor, the antagonist prevents the cell from responding.
i. Potentiation: Enhancement of the effect of one drug by taking it with another drug.
j. Synergism: The action of two substances in which the total effects are greater than the sum of the independent effects
4. Drug abuse occurs in all age groups and at all social levels.
V. Patient Assessment
A. Patients with toxicologic emergencies are generally considered medical patients.
1. May lead to trauma as well
2. General assessment approach is the same for all patients
a. Scene size-up
b. Primary assessment
c. History taking
d. Secondary assessment
e. Reassessment
3. If patient is responsive:
a. Use OPQRST.
b. Obtain vital signs.
c. Obtain SAMPLE history.
d. Perform a rapid scan.
i. Then perform a more thorough physical exam.
4. If the patient is not responsive:
a. Obtain vital signs.
b. Complete a rapid medical assessment.
c. Obtain OPQRST and SAMPLE from bystanders and family members.
B. Scene size-up
1. Patients who have taken an overdose may be dangerous.
a. Call for law enforcement or a crisis unit if necessary.
C. Primary assessment
1. Form a general impression.
2. Rapidly identify concerns with:
a. Mental status
b. Airway
c. Breathing
d. Circulation
3. Threats to life need to be managed.
4. Mechanism of injury or nature of illness should be identified.
5. Identify the need for additional resources.
6. Set the priority of the call.
D. History taking
1. Elaborate on the chief complaint using OPQRST and SAMPLE history.
2. To choose the appropriate course of action, obtain the following:
a. What is the agent?
i. Take to the emergency department:
(a) Any pill bottles, containers, and remaining contents
(b) Sample of any ingested plants
(c) Sample of vomitus
b. When was the poison ingested, injected, absorbed, or inhaled?
i. Strongly influences the decision to induce vomiting or flush out the stomach
(a) Likelihood of retrieving poison from the stomach decreases after 30 to 60 minutes
(b) Acute-onset events indicate a more serious scenario.
c. How much was taken, injected, absorbed, or inhaled?
i. Street drugs are commonly sold in single-dose “hits” or “tabs.”
(a) Three hits equals three times the normal dose.
ii. Almost always a correlation between dose and effects
d. What else was taken?
i. Useful for ED staff when deciding which tests to order
e. Has the patient vomited or aspirated?
i. How soon after the ingestion or exposure?
ii. How much?
f. Why was the substance taken?
i. May not receive a reliable answer
ii. May be trying to get high or using as a coping mechanism
iii. Put answer in quotation marks on patient care report
E. Secondary assessment
1. For trauma, classify as significant or nonsignificant MOI.
a. For significant MOI:
i. Perform a rapid trauma assessment of major body regions.
ii. Obtain baseline vital signs.
iii. Perform a more detailed physical exam en route.
b. For nonsignificant MOI:
i. Perform a more thorough physical exam of the injured body part.
ii. Evaluate:
(a) Distal pulse
(b) Motor and sensory functions
(c) Range of motion
2. At the completion of the physical exam:
a. Prioritize injuries
b. Manage injuries
c. Document findings
F. Reassessment
1. Focuses on:
a. Monitoring the patient’s condition
b. Reprioritizing the patient’s status if necessary
c. Checking the effectiveness of interventions provided
2. Typically done in the ambulance en route to the hospital
VI. Emergency Medical Care
A. ALS care for toxicologic emergencies builds on the following:
1. Ensure scene safety.
2. Maintain the airway.
3. Ensure that breathing is adequate.
4. Ensure that circulation is not compromised.
5. Administer high-concentration supplemental oxygen to achieve saturation levels of 95%.
6. Establish vascular access.
7. Be prepared to manage shock, coma, seizures, and dysrhythmias.
8. Transport the patient as soon as possible.
a. Place in the left lateral recumbent position if there is risk of vomiting.
VII. Pathophysiology, Assessment, and Management of Abuse of and Overdose With Specific Substances
A. Alcohol
1. The most widely abused drug in the United States
a. Red flags pointing to alcoholism include:
i. Drinking early in the day
ii. Drinking alone or in “secret”
iii. Periodic binges
iv. Loss of memory or “blackouts”
v. Tremulousness and anxiety
vi. Cigarette burns on clothing from falling asleep with a lit cigarette
vii. “Green tongue syndrome”
(a) Caused by the use of chlorophyll-containing compounds to disguise the smell of alcohol on the breath
viii. Chronically flushed face and palms
2. Pathophysiology
a. Usually evolves through two distinct phases
i. Problem drinking
(a) Alcohol is used increasingly more often to relieve tensions or other emotional difficulties.
(b) Some degree of psychological dependence develops
(c) Increased absence from work, emotional disturbances, and automobile crashes may occur.
ii. Physical dependence
(a) Results from the regular consumption of large quantities of alcohol
(b) If the person abruptly stops consuming alcohol, withdrawal symptoms will occur.
(c) Minor withdrawal symptoms include:
(1) Restlessness
(2) Anxiousness
(3) Sleeping problems
(4) Agitation
(5) Tremors
(d) Major withdrawal symptoms include:
(1) Increased blood pressure
(2) Vomiting
(3) Hallucinations
(4) Delirium tremens (DTs): Alcohol withdrawal delirium that can be fatal
b. A person with alcoholism is more prone to a number of serious illnesses and injuries.
i. One of the top five causes of death in the United States
ii. Harmful effects on organs decreases life span by 10-20 years.
iii. Alcoholics tend to have:
(a) Chronic malnutrition
(b) Frequent falls
(c) Deterioration in higher mental functions (memory and logical thinking)
(d) Problems with balance
(e) Decreased sensation in the extremities
(f) Gastritis, GERD, or heartburn
(g) Increased risk of cancer of the mouth and esophagus
(h) Increased risk of ulcers, hiatal hernias, and cancers throughout the digestive tract
(i) Coagulopathies (easy bleeding and poor clotting ability)
(j) Hypoglycemia
(k) GI bleeding
(l) Increased risk of acute pancreatitis, pneumonia, and cardiomyopathy
3. Acute alcohol intoxication
a. A form of poisoning
i. Death can occur by the relatively rapid consumption of as little as a half-pint of whisky.
ii. Most immediate danger is death from respiratory depression and/or aspiration of vomitus or stomach contents
b. Treat an unconscious intoxicated patient as you would any unconscious patient.
i. Establish and maintain the airway.
ii. With an intact gag reflex, place the patient in the recovery position and be prepared to suction.
iii. With no gag reflex, intubate.
iv. Give high concentration oxygen.
v. Assist ventilations as necessary.
vi. Establish vascular access.
vii. Monitor ECG rhythm.
viii. Assess blood glucose level.
ix. Administer thiamine 100 mg via slow IV push if directed to do so by medical control.
x. Transport to an appropriate facility.
4. Withdrawal seizures
a. Usually occur within 12 to 48 hours of last drink
b. Use the same care described for alcohol intoxication.
c. Consult with medical control about administering benzodiazepines.
5. Delirium tremens
a. Symptoms usually start 48 to 82 hours after the last alcohol intake.
b. Mortality rate is 15%.
c. Signs and symptoms include:
i. Confusion
ii. Tremors
iii. Restlessness
iv. Fever
v. Diaphoresis
vi. Hallucinations
vii. Hypotension (often due to dehydration)
d. Treatment is aimed at protecting the patient from injury and supporting the cardiovascular system.
e. Try to keep the patient calm.
f. Administer supplemental oxygen by nasal cannula.
g. Establish vascular access.
i. Manage hypotension with an infusion of normal saline.
h. Check breath sounds during reassessment.
i. Maintain an ongoing dialogue to help orient and reassure the patient.
B. Stimulants
1. Stimulant users may become addicted within just a few days.
a. Success of overcoming addiction is low.
b. May be taken orally, smoked, or injected intravenously
c. Clinical presentation includes:
i. Excitement
ii. Delirium
iii. Tachycardia
iv. Hypertension or hypotension with a fast pulse rate
v. Dilated pupils
d. As toxic levels are reached, the patient may experience:
i. Psychosis
ii. Hyperpyrexia
iii. Tremors
iv. Seizures
v. Cardiac arrest
e. Increasing paranoia makes encounters risky.
i. Stay alert for signs of violence or a destabilizing scene.
2. Cocaine
a. A naturally occurring alkaloid that is extracted from the Erythroxylon coca plant leaves found in South America
i. Once processed into cocaine hydrochloride, the active ingredient increases from 2% to 100% pure.
ii. Sold under many street names:
(a) Blow
(b) Flake
(c) Lady
(d) Nose candy
(e) Snow
(f) Toot
iii. In 2009, approximately 1.6 million Americans admitted to being cocaine users.
b. Pathophysiology
i. A local anesthetic and a CNS stimulant
ii. Has the ability to create a euphoria that features enhanced alertness and a tremendous sense of well-being
iii. Has limited use in clinical medicine
iv. Quickly absorbed across mucosal membranes, allowing it to be applied:
(a) Topically
(b) Insufflated (snorted)
(c) Swallowed
(d) Injected intravenously
v. Crack cocaine: Cocaine mixed with baking soda and water that is cooked or baked
vi. Depending on absorption route, effects are felt between 8 seconds to 1 minute
vii. When the effects wear off, the user experiences a “crash”, characterized by:
(a) Depression
(b) Irritability
(c) Sleeplessness
(d) Exhaustion
viii. To avoid crashing, many users seek more cocaine or take a sedative.
(a) Likely that users practice polypharmacy
(b) Speedballing: The combined use of heroin and cocaine simultaneously
(1) Heroin addicts claim cocaine provides relief from withdrawal effects.
c. Assessment
i. A person who has overdosed may exhibit any of the signs and symptoms for stimulants (discussed earlier).
ii. Can cause serious complications, including:
(a) Lethal ECG dysrhythmias
(b) Acute myocardial infarction
(c) Seizures
(d) Stroke
(e) Apnea
(f) Hyperthermia
(g) Pneumothorax
(h) Pneumomediastinum
iii. Has a quinidinelike effect on cardiac conduction, causing widening of the QRS and QT prolongation
iv. Increased dosing levels may produce:
(a) Wide-complex dysrhythmias
(b) Negative inotropic effects with decreased cardiac output
(c) Hypotension
(d) Tachycardia followed by bradycardia
3. Amphetamine, methamphetamine, and amphetamine-like drugs
a. Amphetamines
i. Include:
(a) Methamphetamine (crank or ice)
(b) Methylenedioxyamphetamine (MDA, Adam)
(c) Methylenedioxymethamphetamine (MDMA, Eve, ecstasy)
ii. Have a number of legitimate clinical applications
(a) Nasal decongestants
(b) Diet pills
(c) Drugs used to treat narcolepsy, attention-deficit disorder (ADD), and attention-deficit/hyperactivity disorder (ADHD)
b. Methamphetamine
i. Low-cost, long-acting (up to 12 hours)
ii. Ingredients are available locally
(a) “Meth labs” should be treated as a hazardous material incident.
c. Clinical presentation is almost identical to that of a person abusing cocaine.
i. Primary difference is that effects from these drugs last many hours longer than cocaine.
d. Patient management is the same as for cocaine overdose.
i. Prehospital management is supportive.
ii. Patients can become increasingly paranoid and even psychotic.
(a) Contact law enforcement as necessary.
4. Bath salts
a. Contain an active ingredient that is a pseudoephedrine (Sudafed) reduction drug called methcathinone or a similar methamphetamine knock-off
b. Users typically snort, smoke, or ingest this drug.
c. More serious side effects include:
i. Agitation
ii. Hallucinations
iii. Paranoia
d. The drug has nothing in common with bath salts.
i. Selling it under this label has allowed manufacturers and users to escape the legal restrictions imposed on illicit drugs.
5. Management of stimulant abuse
a. Establish and maintain the airway.
b. Give high-concentration, supplemental oxygen to achieve and maintain saturation levels of 95%.
c. Establish vascular access.
d. Apply the ECG monitor, pulse oximeter, and capnometer.
e. Administer benzodiazepines per local protocol.
f. Manage hypotension with serial fluid infusions of normal saline.
g. Contact medical control regarding administration of nitroprusside for uncontrolled hypertension.
h. Contact medical control for consideration of IM haloperidol for violent behavior.
i. Transport to the appropriate facility.
j. Follow local protocols regarding the use of alpha-beta versus beta blockers to control overly fast pulse rates.
k. Apply ice packs as necessary to reduce hyperthermia.
l. Maintain urine output with aggressive therapy.
i. Regularly assess breath sounds to avoid overhydration.
m. If the patient has a seizure, administer benzodiazepines.
i. If it progresses to status epilepticus, administer:
(a) Phenobarbital (Luminal)
(b) IV or rectal diazepam (Valium)
n. Neuromuscular blockade may be needed to control motor activity to avoid hyperthermia, acidosis, and rhabdomyolysis.
C. Marijuana and cannabis compounds
1. Derived from harvested and dried Cannabis sativa plant
a. Also known as:
i. Weed
ii. Pot
iii. Dope
iv. Smoke
b. Resin from flower tops can be used to produce hashish (hash)
c. Clinical uses are limited, but include:
i. Treatment of glaucoma
ii. Relief of nausea and appetite loss for chemotherapy patients
2. Pathophysiology
a. Primary psychoactive ingredient is delta 9-tetrahydrocannabinol.
b. Usually smoked, but can be ingested
i. Effects from smoking is felt in minutes and can last 2-4 hours.
ii. Effects from ingestion can last twice as long.
c. Does not produce true hallucinations
i. Users may have a distorted sense of time and space and a feeling of unreality.
d. Smoking results in bronchodilation and slight tachycardia.
e. Other signs and symptoms include:
i. Euphoria
ii. Drowsiness
iii. Decreased short-term memory
iv. Diminished motor coordination
v. Increased appetite
vi. Bloodshot eyes
3. Assessment and management
a. Focus on supportive care.
b. The likelihood of serious medical complication is small.
c. Novice users may exhibit some behavioral symptoms.
i. If the patient remains anxious, low-dose benzodiazepines may be administered.
d. Transport is rarely warranted.
4. Spice
a. Sold as incense to skirt existing drug laws.
b. A blend of synthetic cannibinoids
c. Can make people delirious
d. Produces both short-term and long-term psychotic effects
D. Hallucinogens
1. Substance that causes some distortion of sense perception
a. Outcomes are termed “psychedelic effects” and can vary widely.
b. Experience is affected by:
i. User’s previous drug experience
ii. Dose taken
iii. User’s expectations
iv. Social setting
c. Classified into two categories
i. Synthetic
(a) LSD
(b) PCP
(c) Ketamine
ii. Naturally occurring
(a) Mescaline
(b) Psilocybin mushroom
(c) Seeds of the Jimson weed plant
2. LSD
a. Lysergic acid diethylamine (LSD) was discovered in 1947 by Dr. Albert Hoffman.
i. Considered a non-habit-forming drug
ii. Tolerance can occur if taken several days in a row.
b. Pathophysiology
i. Primarily affects the senses rather than changing physiologic functions
(a) Synthesis (crossing of the senses) may occur.
ii. As little as 25 µg can produce significant CNS effects.
(a) A single “hit” is 25 to 100 µg.
(b) Many users may take three or more hits.
(c) There is a proportional increase in the drug’s effects.
(1) Effects usually last 3-4 hours, but can last up to 12 hours.
iii. Physiologic effects usually include:
(a) Mild tachycardia
(b) Mild hypertension
(c) Dilated pupils
iv. In a “bad trip,” the user has a frightening experience, resulting in acute anxiety attack and the physical effects secondary to it.
c. Assessment and management
i. Treatment is primarily supportive.
ii. During transport, limit sensory stimulation as much as possible.
3. Phencyclidine (PCP)
a. Also called angel dust or dust
i. Was developed in the late 1950s
ii. Delirium and psychotic symptoms led to use as an animal tranquilizer.
iii. Now manufactured in clandestine laboratories
(a) Variations in potency and purity are common.
b. Pathophysiology
i. Classified as a dissociative anesthetic
ii. Typically smoked or snorted, but can be injected
iii. Small doses (25-50 mg) can produce signs and symptoms of intoxication
(a) High from a single dose can last 4-6 hours
iv. Common signs include:
(a) Slurred speech
(b) Staggering gait
(c) Tachycardia
(d) Hypertension
(e) Staring blankly for extended periods
(f) Horizontal nystagmus (involuntary, rhythmic movement of the eyes)
(g) Muscle rigidity and grinding of the teeth
v. Mind-body separation, related hallucinations, and violent outbreaks are hallmarks of PCP use.
(a) Users can take pain with no reaction and exhibit almost superhuman strength.
c. Assessment and management
i. Can cause very violent and difficult behavior
(a) Safety of the EMS team is a continuous concern.
ii. Care focuses on trying to calm the patient and addressing any wounds.
iii. Administer benzodiazepines if the patient becomes overly aggressive or violent.
(a) Haloperidol can be given IM in an emergency situation.
iv. Administer high-flow oxygen.
iv. Monitor vital signs.
v. Provide safe transport to an appropriate facility.
4. Ketamine (special K, vitamin K)
a. An analog of PCP
i. Usually stolen from veterinary clinics
ii. Is used clinically in pediatric patients
iii. Colorless and odorless
iv. Commonly found in powdered form
v. Often mixed with a drink, but can be snorted
b. Pathophysiology
i. A dissociative anesthetic
ii. Typical oral dosing is 75-300 mg
(a) Dose reduced to 15-200 mg when snorted
iii. At low doses, user presents with:
(a) Mild inebriation
(b) Dreamy or erotic thoughts
(c) Increased sociability
iv. At higher doses, user may have:
(a) Pronounced nausea
(b) Difficulty moving
(c) Complaint of “entering another reality”
v. In extreme cases, users will enter the “K hole.”
(a) Out of body experiences that may never resolve
c. Assessment and management
i. Violent outbreaks are less likely than with PCP.
ii. Secure the patient well.
iii. Assess and manage ABCs.
iv. Provide oxygen therapy.
v. Establish vascular access if the patient is receptive.
vi. Provide safe transport to the appropriate facility.
5. Peyote and mescaline
a. Used by native tribes in the southwestern United States and Mexico for thousands of years
b. Pathophysiology
i. 3 to 12 dried flower buttons of the peyote cactus equals roughly 200 to 500 mg of mescaline.
(a) Profound vomiting often occurs shortly after ingestion.
ii. Psychedelic experience begins with feelings of increased sensitivity to sensory stimulation.
(a) Flashes of color
(b) A distortion of time and space
(c) Out-of-body experiences
iii. Physical effects may include:
(a) Dilated pupils
(b) Increased pulse rate
(c) Mild hypertension
(d) Increased body temperature
c. Assessment and management
i. Pay attention to the ABCs.
ii. Administer supplemental oxygen.
iii. Monitor vital signs.
iv. Provide positive psychological support.
v. Arrange safe transport to the appropriate facility.
6. Psilocybin mushrooms
a. Typical dose is estimated to be 4-10 mg (approximately 2-4 mushrooms)
b. Pathophysiology
i. Onset of symptoms and hallucinogenic effects is within 30 minutes of ingestion.
ii. Effects last 4-6 hours.
iii. Signs and symptoms include:
(a) Nausea
(b) Vomiting
(c) Mydriasis
(d) Mild tachycardia
(e) Mild hypertension
iv. The likelihood of any serious medical side effects is low.
(a) Seizures and hyperthermia have been reported.
c. Assessment and management
i. Supportive care
ii. Pay attention to ABCs.
iii. Monitor vital signs.
iv. Safely transport to the appropriate facility
v. Establish vascular access if time and circumstances allow.
E. Sedatives and hypnotics
1. Drugs in the sedative-hypnotic category have a wide range of use.
a. Sedative: Reduce anxiety and calm agitation
b. Hypnotic: Used as sleeping aids
c. Function as CNS depressants
2. Barbiturates
a. Have a history of use as sleep aids, anti-anxiety drugs, and seizure control medications
i. Use and abuse peaked in the late 70s.
ii. Combination of alcohol and barbiturates were commonly used for suicide.
(a) Drugs were developed to have fewer depressive effects on respiratory system.
b. Pathophysiology
i. Four basic configurations:
(a) Long-acting
(1) Less lipid soluble
(2) Delayed onset
(3) Long duration of action
(b) Intermediate-acting
(c) Short-acting
(d) Ultra-short-acting
(1) Highly lipid soluble
(2) Exert effects in a matter of minutes
c. Assessment
i. Mild to moderate barbiturate intoxication presents much like alcohol intoxication.
(a) Drowsiness
(b) Decreased inhibitions
(c) Ataxia
(d) Mental confusion
(e) Staggering gait
ii. As dose increases, patient moves down the scale of CNS depression.
(a) Increasingly lethargic
(b) Increasingly lower level of responsiveness
d. Management
i. Airway control is the first priority.
(a) Intubation
(b) Prevent aspiration.
ii. Administer high-concentration supplemental oxygen.
iii. Monitor ECG rhythm.
iv. Establish venous access.
v. Use pulse oximetry and capnography.
vi. If shock develops, rapid infusion of 1-2 L of crystalloids may be needed.
(a) Assess breath sounds before and after each bolus.
vii. If patient has adequate fluid replacement but hypotension persists, administer a vasodepressor.
viii. For long-acting barbiturates, administer a dose of 1-2 mEq of sodium bicarbonate to help alkalinize the urine.
(a) Use of fluid loading and forced diuresis may be indicated.
(b) IV furosemide is contraindicated for patients who are already hypotensive or showing signs of shock.
ix. Gastric emptying is not recommended.
(a) Exception: Patient ingested a life-threatening dose and the procedure can be performed within 60 minutes of ingestion.
(b) Activated charcoal may be a better option.
x. Abrupt cessation in a long-term abuser will produce withdrawal syndrome in approximately 24 hours.
(a) Potentially life-threatening signs and symptoms arise in several days to a week.
(b) Minor withdrawal signs and symptoms:
(1) Restlessness and anxiety
(2) Depression
(3) Insomnia
(4) Diaphoresis
(5) Abdominal cramping
(6) Nausea and vomiting
(c) Severe cases may result in:
(1) Delirium
(2) Hallucinations
(3) Psychosis
(4) Seizures
(5) Hyperthermia
(6) Cardiovascular collapse
(d) Focus treatment on preventing seizures and cardiovascular collapse.
(e) Rapid transport is indicated.
3. Benzodiazepines
a. Commonly used to treat anxiety, seizures, alcohol withdrawal, and insomnia
b. Pathophysiology
i. Exert effects by stimulating the gamma-aminobutyric acid pathways, resulting in:
(a) Sedation
(b) Reduced anxiety
(c) Relaxation of striated muscle
ii. IV route is most desirable in the prehospital setting
c. Assessment
i. Patient may be using other drugs as well as alcohol.
ii. Single-entity overdose has a low morbidity or mortality rate.
iii. Most common clinical effects:
(a) Altered mentation
(b) Drowsiness
(c) Confusion
(d) Slurred speech
(e) Ataxia
(f) General incoordination
iv. Think beyond a simple benzodiazepine event if patients present with:
(a) Severe respiratory depression
(b) Hypotension
(c) Coma
d. Management
i. Assess and manage the airway.
ii. Administer high-concentration supplemental oxygen.
iii. Establish vascular access.
iv. Apply the ECG monitor, pulse oximeter, and capnometer.
v. Consider administering flumazenil via slow IV push.
(a) Contraindicated for patients with head injuries and elevated intracranial pressure
vi. Transport to appropriate facility.
F. Narcotics, opiates, and opioids
1. Narcotic: A drug that produces sleep or altered mental status
a. Classified into:
i. Opiate: Natural drugs derived from opium
ii. Opioid: Non-opium-derived synthetics
b. Abuse of narcotics is one of the most common causes of overdose deaths.
c. Narcotic agents include:
i. Morphine
ii. Codeine
iii. Heroin
iv. Fentanyl
v. Hydrocodone
vi. Oxycodone
vii. Meperidine
viii. Propoxyphene
ix. Dextromethorphan
d. Agents differ greatly in effects and potency.
2. Pathophysiology
a. Opioids produce their major effects by binding with receptor sites in the brain and other tissues.
b. Opioids are readily absorbed from the GI tract but can also be absorbed from:
i. Nasal mucosa (when snorted)
ii. Lungs (smoking)
c. Effects are lessened when taken orally due to first-pass metabolism.
d. A dose of naloxone may not permanently reverse the effects of heroin.
i. Patient may lapse into unconsciousness again 15-20 minutes later
e. Morphine is a commonly used analgesic and a potent vasodilator.
i. Half-life in young adults: 2-3 hours
(a) Typically longer in older adults
3. Assessment
a. Classic presentation features:
i. Euphoria
ii. Hypotension
iii. Respiratory depression
iv. Pinpoint pupils
b. Certain agents may include:
i. Nausea
ii. Vomiting
iii. Constipation
iv. Allergic phenomena
c. Increased doses may cause:
i. Coma
ii. Seizures
iii. Cardiac arrest
d. Morphine and heroin produce a dreamlike state.
i. User may appear to pass out, but is typically lucid
4. Management
a. Focuses on establishing and maintaining a patent airway and providing adequate ventilation.
i. The following are common:
(a) Hypoventilation
(b) Shallow respirations
ii. Place an oropharyngeal airway, and provide bag-mask ventilation with 15 L/min of supplemental oxygen.
b. Establish vascular access.
i. Administer 0.4 to 2 mg. of naloxone.
(a) Abrupt reversal of consciousness may make the patient angry.
(b) Administer just enough to improve respirations, rather than waking up the patient completely.
c. If the patient does not respond to naloxone:
i. They may have taken a potent synthetic drug such as fentanyl.
(a) A much higher dose is required.
ii. They may have taken multiple drugs, some of which do not respond to naloxone.
(a) Insert an advanced airway, and provide transport to an appropriate facility
G. Cardiac medications
1. Pathophysiology
a. Alter the function or electrical rhythm of the heart
b. Major classes of drugs used as part of cardiac treatment regimens include:
i. Antidysrhythmics
ii. Beta blockers
iii. Calcium channel blockers
iv. Cardiac glycosides
v. Antigiotensin-converting enzyme inhibitors
c. Many patients take a combination of drugs
d. Many of these medications have potentially life-threatening adverse effects.
i. Overdoses are usually accidental.
ii. Overdose of more than twice the prescribed daily dose should be considered potentially life-threatening.
iii. A single adult pill or tablet can cause serious effects in small children and infants.
e. Type I antidysrhythmic medications
i. Includes procainamide (Pronestyl) and lidocaine
ii. Inhibit fast sodium channels within the heart, affecting depolarization and impulse conduction
iii. Overdose will produce a variety of symptoms including:
(a) Myocardial depression
(b) Impaired conduction
(c) Decreased contractility
iv. Treatment of overdose is usually supportive.
(a) In certain instances, IV sodium bicarbonate may be used to treat:
(1) QT prolongation
(2) Bradycardia
(3) Hypotension
f. Type II antidysrhythmic (beta-adrenergic antagonist/beta blocker) medications
i. Primarily used to control pulse rate and blood pressure
ii. Prevents catecholamines from activating beta1-adrenergic receptors in the heart and blood vessels
iii. Toxicity may present with:
(a) Hypotension
(b) Bradycardia
(c) Dizziness
(d) Syncope
(e) Altered mental status
(f) Hypoglycemia and hyperkalemia
(g) Bronchospasm
iv. High doses of IV glucagon is the antidote to toxicity.
(a) Generally requires more glucagon than is generally available on most ALS ambulances.
(b) Risk of toxicity from the phenol used to reconstitute the dry glucagon powder
v. Atropine, epinephrine infusion, and cardiac pacing may be required in severe cases.
g. Type III antidysrhythmic medications
i. Block cardiac cell potassium channels
(a) Causes a prolongation of the cardiac action potential
(b) Increases the effective refractory period
ii. Amiodarone (Cordorone) is used in the prehospital setting.
iii. Acute toxicity may present as:
(a) Hypotension
(b) Bradycardia
(c) Certain ventricular dysrhythmias
iv. Treatment is primarily supportive.
(a) IV magnesium sulfate may be used to treat torsades de pointes.
h. Type IV antidysrhythmic (calcium channel blocker) medications
i. Used for control of pulse rate and blood pressure as well as a wide variety of seemingly unrelated medical conditions
ii. Verapamil (Calan) and diltiazem (Cardizem) are used in the prehospital setting.
iii. Slow calcium influx into cells present in the heart, blood vessels, and other types of smooth muscle
iv. Therapeutic use and toxicity cause:
(a) Decrease in pulse rate
(b) Decreased myocardial contractility
(c) Vasodilation
v. May also cause:
(a) Hyperglycemia
(b) Nausea, vomiting
(c) Altered mental status
(d) Metabolic acidosis
vi. IV calcium chloride or calcium gluconate is the initial treatment for toxicity.
(a) Refractory hypotension and bradycardia can be treated with an IV epinephrine infusion.
2. Assessment and management
a. Signs and symptoms vary but may include:
i. Hypotension
ii. Weakness
iii. Confusion
iv. Nausea
v. Vomiting
vi. Rhythm disturbances
vii. Headache
viii. Difficulty breathing
b. Ensure a patent airway.
c. Provide adequate ventilation.
d. Administer high-flow supplemental oxygen.
e. Establish vascular access.
i. Beta blocker overdose: Glucagon, but may require dosing in excess of what is carried in ambulance
ii. Calcium channel blocker overdose: Calcium gluconate and calcium chloride
iii. Cardiac glycosides overdose: Digoxin Immune Fab
iv. Hypotension: Sequential fluid boluses of normal saline
f. Maintain contact with medical control.
H. Organophosphates
1. A major component in many insecticides used in agriculture and in the home
a. Include:
i. Acephate
ii. Diazinon
iii. Malathion
iv. Carbamates
v. Warfarins
vi. Pyrethrums
b. Death rate of 10% for adults and 50% for children
c. Common exposure causes include:
i. Suicide
ii. Accidental agricultural exposure
iii. Manufacturing
2. Pathophysiology
a. Exert their toxic effects at junctions of the nerve cells of the autonomic nervous system.
b. Symptoms are fundamentally the same regardless of entry by ingestion, inhalation, or absorption:
i. Anxiety and restlessness
ii. Headache
iii. Dizziness
iv. Confusion
v. Tremors
vi. Seizures
vii. Dyspnea
viii. Diffuse wheezing
ix. Respiratory depression
x. Loss of consciousness
c. Signs and symptoms will usually present within the first 8 hours.
d. SLUDGE is helpful in diagnosis.
i. Salivation
ii. Lacrimation
iii. Urination
iv. Defecation
v. Gastric upset
vi. Emesis
3. Assessment and management
a. Decontaminate and remove all contaminated clothing before initiating care.
i. Clothing should be disposed of as hazardous materials.
ii. Patient should be scrubbed with soap and water.
b. Establish and maintain the airway.
c. Suction as needed.
d. Deliver high-flow oxygen to achieve and maintain saturation levels of 95%.
e. Establish vascular access.
f. Administer 1.0 mg atropine IV push.
i. Repeat the dose every 3 to 5 minutes until symptoms reversal occurs.
g. Administer 1 to 2 g of pralidoxime (2-PAM) infused with normal saline during 5 to 10 minutes.
h. Apply the ECG monitor, pulse oximeter, and capnometer.
i. Immediately transport to the appropriate facility.
I. Carbon monoxide
1. Causes more poisoning deaths than another other substances
a. Produced during the incomplete combustion of organic fuels
b. Approximately half of successful adult suicides are caused by CO.
i. A running automobile in a closed garage can produce a lethal CO concentration in as little as 30 minutes.
2. Pathophysiology
a. A colorless, odorless, tasteless gas
b. Displaces oxygen, preventing RBCs from carrying oxygen to the tissues
i. Leads to suffocation at the cellular level
ii. Level of CO does not need to be very high for poisoning to occur.
(a) Any activity that increases the body’s oxygen requirement will increase the severity of the poisoning.
(b) Children tend to have more severe symptoms.
3. Assessment
a. Can be difficult to diagnose in the field
b. Signs and symptoms are variable and vague, but may include:
i. Headache
ii. Nausea
iii. Vomiting
iv. Confusion
v. Sensation of pressure in the head or roaring in the ears
c. Physical examination may reveal:
i. Bounding pulses
ii. Dilated pupils
iii. Pallor or cyanosis
iv. Cherry red color of the skin (late sign)
d. Consider CO poisoning when you have several people who have shared the same accommodations with the same symptoms.
e. Pulse oximetry readings will not be accurate.
f. ECG monitor may help to assess for cardiac ischemia.
4. Management
a. Aimed at providing the highest concentration of oxygen possible
i. For mild cases, elimination half-time of carboxyhemoglobin is about 4 hours.
(a) With treatment of 100% oxygen, this can be reduced to about 1.5 hours.
(b) With hyperbaric oxygen therapy, this can be reduced to 15 to 20 minutes.
b. Remove the patient from the exposure environment.
c. Establish and maintain the airway.
d. Give high-flow supplemental oxygen by a tight-fitting nonrebreathing mask to achieve and maintain a saturation level of 95%.
e. Establish vascular access.
f. Keep the patient quiet and at rest to minimize oxygen demand.
g. Monitor the ECG rhythm and LOC.
h. Transport to the appropriate facility.
i. For patients with injuries or illness from fire, consider the possibility of combined CO/cyanide poisoning.
i. Contact medical control to administer amyl nitrate or sodium thiosulfate.
j. CO poisoning can be reversed if diagnosed and treated in time.
J. Chlorine gas
1. Chlorine compounds are commonly used in the home and in occupational settings.
2. Pathophysiology
a. Signs and symptoms depend on the concentration of the inhaled gas and the duration of exposure.
i. Extremely irritating to all mucous membranes
ii. Minor exposure:
(a) Burning sensation in eyes, nose, and throat
(b) Slight cough
iii. More intense exposure:
(a) Chest tightness
(b) Choking
(c) Paroxysmal cough
(d) Headache
(e) Nausea
(f) Vomiting
(g) Diffuse wheezing
iv. Even more severe exposure:
(a) Cyanosis
(b) Crackles in the chest
(c) Shock
(d) Seizures
(e) Loss of consciousness
3. Assessment and management
a. First priority is to remove all patients from the area of exposure.
i. Park the ambulance upwind if there is a serious spill.
ii. All rescuers must wear protective breathing apparatus.
b. Triage patients.
i. Patients with respiratory distress are priority.
c. Deliver high-concentration humidified oxygen by mask.
d. Consider intubation and rapid-sequence intubation.
e. Irrigate burning or itching eyes with water.
f. Irrigate skin that has been in contact with the chlorine.
K. Cyanide
1. Used in industry for electroplating, ore extraction, and fumigation
a. May also be contained in commercial products or the seeds of cherries, apples, pears, and apricots
2. Pathophysiology
a. One of the most rapid-acting and deadly poisons
b. Combines with a crucial cellular enzyme (cytochrome oxidase), which blocks utilization of oxygen at the cellular level, resulting in:
i. Cellular suffocation
ii. Death within seconds if inhaled
iii. Death within minutes to possibly an hour or two if ingested
3. Assessment
a. Patient may have an altered mental status
b. Signs and symptoms may include:
i. Headache
ii. Palpitations
iii. Dyspnea
iv. Odor of almonds on the breath
v. Rapid and labored respirations
(a) Become slow and gasping with progression
vi. Rapid and thread pulses
vii. Vomiting, seizures, and coma
viii. Bright red venous blood and body
4. Management
a. A dire emergency that should be treated as fast as possible
b. Aimed at displacing the cyanide from the cytochrome oxidase by introducing another chemical that will “attract” the cyanide
i. In the prehospital setting, amyl nitrite is used.
c. If cyanide was inhaled:
i. Remove the patient from the source.
ii. Establish an airway.
iii. Administer 100% supplemental oxygen.
iv. Assist ventilations as needed.
d. Use the commercially available cyanide antidote kit if available.
i. IV administration of 50 mL of sodium thiosulfate solution
ii. If kit is not available, break a vial of amyl nitrite into a gauze pad.
(a) Hold it over the patient’s nose for about 20 seconds, and then remove it.
(b) Allow the patient to breathe a high concentration of oxygen for about 40 seconds.
(c) Keep switching back and forth.
(d) Your partner should establish vascular access at this time.
(e) Anticipate hypotension.
(1) Keep patient supine with legs elevated.
(2) If systolic blood pressure drops below 80 mm Hg, consult medical control regarding administering an IV vasopressor.
(3) Monitor the ECG rhythm.
(4) Notify the receiving hospital of the probable diagnosis.
(5) Transport without delay.
e. Hydroxocobalamin
i. A safe alternative or adjunct to the traditional treatment of cyanide poisoning
ii. Included in the commercially available “Cyanokit”
(a) Patients are given 5 g IV over 30 minutes.
iii. Allergy/anaphylaxis is the primary concern.
f. Methylene blue
i. An antidote used to treat methemoglobinemia that may occur during the treatment of cyanide poisoning with sodium nitrite
(a) Methemoglobinemia: Alteration of the structure of hemoglobin
(1) Induced by the administration of amyl nitrite and sodium nitrite
(2) Should be avoided in mild cases of cyanide poisoning
ii. Typically administered under the guidance of an expert
L. Caustics
1. Strong acids (pH < 2.0) and strong alkalis (pH > 12.0)
a. Commonly used in industry, agriculture, and the home
b. Approximately 100,000 exposures occur each year in the United States
i. Mostly involves accidental dermal or ocular exposure
ii. Cases involving oral ingestion are often intentional suicide attempts.
2. Pathophysiology
a. Cause direct chemical injury to the tissues they contact
b. Signs and symptoms include:
i. Severe pain
ii. Burns
iii. Difficulty talking or swallowing
iv. Hypoperfusion or shock
3. Assessment and management
a. Most patients who have swallowed these substances present with severe pain in the mouth, throat, and chest.
i. If respiratory distress is present, it is likely due to soft tissue swelling.
(a) Patient is in immediate danger of complete airway obstruction.
b. For caustic ingestion:
i. Give milk if the Poison Center or medical control agrees.
(a) 6 to 8 ounces for child
(b) 8 to 12 ounces for an adult
ii. Establish vascular access.
iii. Immediate transport is indicated.
c. For dermal exposure:
i. Dilute and flush away substance.
d. For eye exposure:
i. Cut off the prong section of a nasal cannula and place it on the bridge of the patient’s nose.
ii. Plug in a macro IV administration set, and run it wide open to provide continuous irrigation.
iii. A Morgan lens may be used after initial gross flushing.
e. Significant “do not’s” for caustic ingestions:
i. Do not give any “neutralizing substances.”
(a) Mixing an acid and an alkali produces heat.
ii. Do not induce vomiting.
iii. Do not perform gastric lavage.
iv. Do not give activated charcoal.
M. Common household items
1. The average home is full of dangerous substances.
a. Houseplants that have poisonous leaves or berries
b. Pesticides and herbicides used in lawn and garden care
c. Hydrocarbon products
d. Glue
e. Cleaning agents
2. Always remember that the Poison Center is an invaluable resource.
N. Drugs abused for sexual purposes
1. Drugs that increase sexual gratification
a. Sildenafil (Viagra)
i. Erectile dysfunction medication
ii. Contraindicated for patients who take nitrites for cardiac problems
(a) May result in serious hypotension or total cardiovascular collapse
(b) For hypotension, repeated boluses of normal saline can bring blood pressure down.
(c) For cardiac arrest, follow local protocols.
b. Marijuana
i. No overdose potential
ii. Supportive care is indicated.
c. Cocaine and other stimulant drugs
i. Tachycardia and hypotension as a result of inadequate preload can occur.
(a) Be alert for this when pulse rate is 170 to 180 beats/min or higher.
(b) Serial boluses of normal saline will normally stabilize blood pressure.
(c) If boluses are not effective, a vasopressor or dobutamine may be required.
d. Amyl nitrite
i. Can be crushed and inhaled
ii. Hypotension may result from blood pooling in the periphery owing to the drug’s vasodilatory effects.
e. Ecstasy
i. Creates an incredible sense of well-being
f. Dextromethorphan
i. Found in almost 150 over-the-counter cough suppressants
ii. Can produce a euphoric floating sensation
iii. With approximately 6 tablets, DXM produces mild stimulant effect.
iv. Consuming large quantities can lead to:
(a) Hallucinations
(b) Psychedelic visions
(c) Loss of motor control
(d) Confusion
(e) Blurred vision
(f) Dreamlike euphoria
(g) Out-of-body sensations
2. Drugs used to facilitate sexual assault
a. Also known as “date rape” drugs
b. GHB (gamma-hydroxybutyrate)
i. An endogenous metabolite of gamma-aminobutyric acid
(a) Neuromodulator involved with sleep cycles, memory retention, and emotional control
ii. Odorless and colorless liquid, with a salty taste
iii. Exerts its effects within 30 to 60 minutes
iv. As little as 0.5 mg can produce a pronounced hypnotic effect along with:
(a) Disinhibition
(b) Severe passivity
(c) Antegrade amnesia
v. Alcohol increases the risk of potentially lethal CNS depression.
vi. Methamphetamine and similar drugs increase the risk of seizures.
vii. Treatment focuses on the CNS depression and airway protection:
(a) Establish and maintain the airway.
(b) Monitor LOC.
(c) Assist breathing as necessary.
(d) Administer high-flow supplemental oxygen.
(e) Establish vascular access.
(f) Apply the ECG monitor, pulse oximeter, and capnometer.
(g) Provide rapid transport to the emergency department.
c. Rohypnol (roofies)
i. Potent benzodiazepine
ii. Illegal to make or distribute
O. Poisonous alcohols
1. Alcohols manufactured for industrial or nongastronomic purposes
2. Methyl alcohol (wood alcohol or methanol)
a. Present in paints, paint remover, windshield washer fluids, varnishes, antifreeze, and canned fuels
b. Pathophysiology
i. Methanol itself is not harmful.
(a) Its breakdown products, formaldehyde and formic acid, are responsible for methanol poisoning.
ii. A dose of 30 mL can produce toxicity and even death.
iii. Peak blood levels attained within 30 to 90 minutes.
iv. In mild toxicity, the half-life is 14 to 20 hours.
(a) Increases to 24 to 30 hours in severe cases
c. Assessment
i. Symptoms begin 12-18 hours after ingestion and may include:
(a) Nausea and vomiting
(b) Headache or vertigo
(c) Abdominal pain
(d) Blurred vision or blindness
ii. Physical exam findings may include:
(a) Odor of alcohol on the breath
(b) Altered mental status
(c) Dilated pupils with sluggish or no reaction
(d) Hyperpnea
(e) Tachypnea
(f) Bradycardia
(g) Hypotension
d. Management
i. Field care is primarily supportive.
ii. Establish and manage the airway.
iii. Establish vascular access.
iv. Assess blood glucose level.
(a) Administer glucose and thiamine per local protocol.
v. Consult medical control for consideration of sodium bicarbonate.
vi. Provide immediate transport.
vii. If patient is alert and local protocol allows, insert a nasogastric tube and attempt to aspirate the gastric contents.
viii. Activated charcoal is contraindicated unless other absorbable drugs have been ingested.
3. Ethylene glycol
a. A colorless, odorless liquid
i. Found in a variety of commercial products:
(a) Antifreeze
(b) Coolant
(c) Deicers
(d) Polishes
(e) Paints
ii. Lethal dose is estimated to be 2 mL/kg, or as little as 150 mL
b. Pathophysiology
i. Water-soluble
(a) Absorbed rapidly when taken orally
(b) Peak blood levels within 1 to 4 hours
ii. Liver and kidneys metabolize it into a number of toxic metabolites:
(a) Aldehydes
(b) Lactate
(c) Oxalate
(d) Glycolate
iii. These metabolites produce metabolic acidosis.
c. Assessment
i. Toxicity occurs in three stages.
(a) Stage 1: 20 minutes to 12 hours after ingestion
(1) CNS depression and intoxicated appearance
(2) Odor of ethanol on the breath is notably absent
(3) Nausea, vomiting, seizures, or coma
(b) Stage 2: 12 to 24 hours after ingestion
(1) Tachypnea, tachycardia, mild hypertension, and rales
(2) Congestive heart failure, and cardiovascular collapse
(c) Stage 3: 24 to 72 hours after ingestion
(1) Renal damage becomes evident with flank pain and anuria (absence of urine formation).
d. Management
i. Care plan is the same as for methanol poisoning
(a) Exception: May be ordered by medical control to administer 10 mL of 10% calcium gluconate via slow IV push to treat hypocalcemia.
ii. Once at the hospital, care focuses on:
(a) Correction of acidosis
(b) Administration of fomepizole or ethanol
(c) Renal dialysis
P. Hydrocarbons
1. Compounds made up of hydrogen and carbon atoms, mostly obtained from distillation of petroleum
a. Found in a variety of products around the home, including:
i. Cleaning and polishing agents
ii. Glues
iii. Spot removers
iv. Lighter fluids
v. Paints
vi. Paint thinners and paint removers
vii. Fuels
viii. Pesticides
2. Hydrocarbon inhalation
a. “Bagging” or “huffing” everyday products, which may include:
i. Paint thinner
ii. Solvents
iii. Paint strippers
iv. Gasoline
v. Nonstick cooking spray
vi. Glues
b. Long-term inhalant abuse can lead to permanent loss of mental function, such as:
i. Loss of hearing
ii. Loss of fine motor function
iii. Balance and equilibrium disorders
iv. Death
c. “Huffing”: Breathing fumes directly off a soaked rag or towel
d. “Bagging”: Placing a soaked rag or towel into a bag and holding the bag over one’s face to breathe in the fumes
e. Primary goals of treatment focus on:
i. Removal from the noxious environment
ii. Administering high-concentration supplemental oxygen
iii. Prompt transport to the appropriate facility
3. Hydrocarbon ingestion
a. Pathophysiology
i. Common among children younger than 5 years
ii. The lower the viscosity of the agent, the higher the risk of aspiration and other complications.
(a) Most hydrocarbon ingestions do not produce lasting damage.
iii. Low viscosity hydrocarbons can easily enter the lungs during swallowing.
(a) Assume aspiration if after swallowing the patient immediately reports:
(1) Coughing
(2) Choking
(3) Vomiting
(b) Any signs of respiratory distress should be considered a danger sign.
iv. Low viscosity facilitates the uptake of a hydrocarbon by tissues of the CNS and its anesthetic effects.
(a) Initial experience of excitement and euphoria
(b) Followed by weakness, incoordination, drowsiness, confusion, and coma
(c) Some petroleum products can produce hypoglycemia and cardiac dysrhythmias.
v. Many products cause gastric irritation.
(a) Just a single exposure may cause sudden death.
b. Assessment and management
i. In one study, fewer than 1% of patients suspected of ingestion required physician intervention.
ii. All symptomatic patients should be transported immediately.
iii. Management should include:
(a) Remove contaminated clothing and decontaminate the patient.
(b) Establish and maintain the airway, and ensure adequate ventilation.
(c) Administer high-flow supplemental oxygen to achieve and maintain blood saturation levels of 95%.
(d) Establish vascular access.
(e) Continuously monitor the ECG rhythm; consider running a 12-lead.
(f) Administer sequential bolus infusions of normal saline to treat hypotension.
(g) Transport the patient to the most appropriate facility.
Q. Hydrofluoric acid/hydrogen fluoride
1. Pathophysiology
a. Hydrofluoric acid: Hydrogen fluoride that has been placed into an aqueous solution
i. Can cause devastating local and systemic toxicity from exposure to an extremely small amount
b. Leaches calcium and magnesium from body tissues, resulting in:
i. Profound hypocalcemia and hypomagnesemia
ii. A massive release of sequestered potassium into the systemic circulation
c. Inhalation may cause:
i. Throat discomfort
ii. Bronchospasm
iii. Stridor
iv. Local airway injury
v. Wheezes, rhonchi, rales
vi. Delayed chemical pneumonitis or pulmonary edema
d. Ingestion may cause:
i. Vomiting
ii. Abdominal pain
iii. Gastritis
iv. Profound systemic toxicity
(a) Hypocalcemia
(b) Electrolyte imbalance
(c) Dysrhythmias
(d) Tetany
(e) Muscle spasms
(f) Vasospasm
(g) Acidemia
2. Assessment and management
a. Patients may deteriorate rapidly.
b. Manage the ABCs.
c. For ingestion, provide immediate stomach evacuation with a nasogastric or orogastric tube.
d. Administer a calcium- or magnesium-containing substance:
i. Milk
ii. Antacids
iii. Magnesium citrate
iv. Magnesium hydroxide
R. Hydrogen sulfide
1. Pathophysiology
a. A highly toxic, colorless gas, with a distinctive rotten-egg odor
b. Poisoning usually occurs by inhalation.
c. Affects all organs, but has the most impact on the lungs and CNS
d. Chronic exposure may cause patients to lose their ability to smell the gas.
e. Low-level exposure can cause:
i. Eye, nose, and throat irritation
ii. Headache
iii. Bronchitis
f. High-concentration exposure can cause:
i. Nausea and vomiting
ii. Confusion
iii. Dyspnea
iv. Loss of consciousness
g. Very high concentrations can cause:
i. Seizures
ii. Shock
iii. Coma
iv. Cardiopulmonary arrest
2. Assessment and management
a. No proven antidote for HS poisoning
b. Quickly remove the patient from the contaminated area.
c. Management is largely supportive.
i. Monitor and assist respiratory and cardiovascular functions as needed.
S. Oxides of nitrogen
1. Includes nitric oxide and nitrogen dioxide
a. Nitric oxide: Colorless or brownish at room temperature, with a sweet smell
b. Nitrogen dioxide: Colorless or brownish, with a harsh odor
c. Exposure may come from kerosene heaters in the home or from facilities that produce nitric acid.
2. Pathophysiology
a. Exposure can result in:
i. Irritation of the throat and upper respiratory tract
ii. Buildup of fluid in the lungs
iii. Difficulty breathing
3. Assessment and management
a. Use a self-contained breathing apparatus when entering the scene.
b. Prehospital treatment includes:
i. Immediately remove the patient from the environment.
ii. Provide supportive care.
iii. Gain IV access.
iv. Be prepared to perform endotracheal intubation.
T. Psychiatric medications
1. Designed to alter dysfunctions of mood and affect and thought, orientation, or perception
2. Tricyclic antidepressants
a. Pathophysiology
i. Once the drug of choice to treat depression
ii. Require close attention to compliance with dosing regimens
iii. Small therapeutic window
(a) Even minimal dosing may cause toxic effects.
iv. Involved in more deaths than any other class of medication
v. The five most likely to be involved in drug-related events in the United States:
(a) Amitriptyline
(b) Imipramine
(c) Doxepin
(d) Nortriptyline
(e) Desipramine
vi. May now be used for pain management
b. Assessment
i. Signs and symptoms may vary dramatically among patients.
ii. Most common signs and symptoms are:
(a) Altered mental status
(b) Dysrhythmias
(c) Dry mouth
(d) Blurred vision
(e) Dilated pupils
(f) Urinary retention
(g) Constipation
(h) Pulmonary edema
iii. More serious toxic exposure may cause:
(a) Ventricular tachycardia
(b) Hypotension
(c) Respiratory depression
(d) QT prolongation on ECG
(e) Seizures
iv. The most common cause of death from these drugs is cardiac dysrhythmia.
v. A patient who presents with serious signs and symptoms within 6 hours of ingestion should be considered critical.
c. Management
i. Maintain the airway.
ii. Administer high-flow supplemental oxygen.
iii. Establish vascular access.
iv. Provide continuous ECG monitoring.
v. Administer activated charcoal per medical control orders.
vi. Consult with medical control to consider sodium bicarbonate administration.
vii. Manage hypotension with sequential boluses of normal saline.
viii. Assess blood glucose levels.
(a) Give D50 if patient is hypoglycemic.
ix. Rule out head trauma.
x. Be alert for agitation or violence.
xi. Do not give flumazenil or physostigmine.
xii. For seizures, consider administration of benzodiazepines, and consider rapid-sequence intubation or endotracheal intubation.
xiii. Provide rapid transport to the appropriate facility.
3. Monoamine oxidase inhibitors (MAOIs)
a. Pathophysiology
i. Used primarily to treat atypical depression
ii. Increase norepinephrine and serotonin levels within the CNS
iii. Major potential for drug interactions
iv. Tight therapeutic window
(a) As little as 2 mg/kg may produce a life-threatening event.
v. Can precipitate a hypertensive crisis if taken with tyramine-containing foods
vi. Can produce hyperkalemia, metabolic acidosis, and rhabdomyolysis
b. Assessment
i. Symptoms are often delayed 6-12 hours or more following ingestion.
ii. Prepare to manage a life-threatening event.
iii. Early signs and symptoms include:
(a) Hyperactivity
(b) Dysrhythmias
(c) Hyperventilation
(d) Nystagmus
iv. With increased levels of toxicity, be alert for:
(a) Chest pain
(b) Palpitations
(c) Hypertension
(d) Diaphoresis
(e) Agitated or combative behavior
(f) Marked hyperthermia
(g) Hallucinations
v. With a severe overdose, expect:
(a) Bradycardia
(b) Hypotension
(c) Seizures
(d) Worsening hyperthermia
(e) Pulmonary edema
(f) Coma
(g) Cardiac arrest
c. Management
i. No antidote available for overdose
ii. Establish and maintain the airway.
iii. Administer high-flow supplemental oxygen.
iv. Establish large-bore vascular access.
v. Monitor the ECG rhythm
vi. After consulting medical control, you may give a single dose of activated charcoal.
(a) Do not give syrup of ipecac.
vii. Treat hypotension with sequential fluid boluses of normal saline.
viii. If seizures occur, treat with benzodiazepines per local protocol.
ix. If the patient is hypertensive, contact medical control to consider administration of phentolamine boluses every 10 to 15 minutes.
x. If rapid sequence intubation is required, the use of a nondepolarizing paralytic is recommended.
4. Selective serotonin reuptake inhibitors
a. Pathophysiology
i. Have a larger therapeutic window
ii. Fewer anticholinergic and cardiac effects than TCAs
iii. Includes fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft)
b. Assessment
i. As many as 50% of adult patients may be asymptomatic with an overdose.
ii. When symptoms are seen, the most commonly seen are:
(a) Nausea
(b) Vomiting
(c) Dysrhythmias
(d) Sedation
(e) Tremors
iii. Symptoms seen less often include:
(a) Dilated pupils
(b) Agitation
(c) Blood pressure changes
(d) Seizures
(e) Hallucinations
iv. When taken in conjunction with alcohol, look for:
(a) Tachycardia
(b) Mild Hypotension
(c) Lethargy
c. Management
i. An overdose with no other drugs or alcohol involved usually produces limited toxic effects.
ii. Management follows a general approach:
(a) Establish and maintain the airway.
(b) Administer high-flow supplemental oxygen.
(c) Establish vascular access.
(d) Provide continuous ECG monitoring.
(e) Consider a single dose of activated charcoal per medical control orders.
(f) Treat seizures activity with benzodiazepines per local protocol.
(g) If widening of the QRS occurs, consult with medical control for consideration of sodium bicarbonate administration.
(h) Transport to appropriate facility.
d. Serotonin syndrome
i. An idiosyncratic complication that occasionally occurs with antidepressant therapy
ii. Can occur with any combination of drugs that increase central serotonin neurotransmission
iii. Difficult to diagnosis
(a) Based on clinical suspicion after other psychiatric or medical causes have been ruled out
iv. Lower muscle rigidity is one of the few classic signs.
(a) May also include confusion or disorientation and agitation
v. Rare, but potentially lethal
(a) One of 10 patients dies.
vi. Primary treatment is to discontinue drug therapy.
vii. Field management is supportive.
(a) 25% of patients require intubation.
5. Lithium
a. Cornerstone drug for the treatment of bipolar disorder
b. Pathophysiology
i. Almost completely absorbed in the GI tract roughly 8 hours after ingestion
(a) Two-thirds of the dose is excreted within 12 hours.
(b) The remainder is excreted during the next two weeks.
ii. High risk of toxic levels and overdose
c. Assessment
i. Early signs and symptoms include:
(a) Nausea
(b) Vomiting
(c) Hand tremors
(d) Excessive thirst
(e) Slurred speech
ii. With increased toxicity come increased neurologic symptoms:
(a) Ataxia
(b) Muscle weakness
(c) Incoordination
(d) Blurred vision
(e) Hyperreflexia (twitching)
iii. The patient may eventually have seizures and become comatose.
d. Management
i. Establish and maintain the airway.
ii. Provide high-concentration supplemental oxygen.
iii. Establish vascular access.
iv. If the patient experiences hypotension, administer serial boluses of normal saline.
v. Maintain continuous ECG monitoring.
vi. Transport to appropriate facility.
U. Nonprescription pain medications
1. Pathophysiology
a. Nonsteroidal anti-inflammatory drugs (NSAIDs) are rapidly absorbed from the GI tract before being eliminated from the body in urine and feces.
b. Half lives vary widely
i. 2-4 hours for ibuprofen
ii. 50 hours for some long-acting agents
c. Most problems involve long-term use:
i. GI bleeding
ii. Kidney dysfunction
d. Acute ingestion and overdoses are rare.
2. Assessment
a. Signs and symptoms may include:
i. Headache
ii. Altered mentation
iii. Seizures
iv. Bradydysrhythmia
v. Hypotension
vi. Abdominal pain
vii. Nausea
viii. Vomiting
b. Many patients remain asymptomatic.
3. Management
a. Establish and maintain the airway.
b. Administer high-concentration supplemental oxygen.
c. Establish vascular access.
d. Administer fluid boluses of normal saline for hypotension.
i. If it persists, consider giving a vasopressor.
e. Treat seizures with benzodiazepines per local protocol.
f. Transport to appropriate facility.
g. A unique side effect is aseptic meningitis.
i. Patient presents with complaints of stiff neck, headache, and fever.
ii. Discontinuing use generally resolves the problem.
iii. Patients should be evaluated at the hospital to rule out other problems.
4. Salicylates
a. Includes aspirin, Pepto-Bismol, liniments used with hot-air vaporizers
b. Pathophysiology
i. Clinical presentation can change based on three variables:
(a) Patient’s age
(b) Dose ingested
(c) Duration of exposure
ii. Ingestion of 150 mg/kg (mildly toxic) may produce:
(a) Nausea
(b) Vomiting
(c) Abdominal pain
iii. Ingestion of 150 to 300 mg/kg (moderate toxicity) may produce:
(a) Vomiting
(b) Diaphoresis
(c) Hyperpnea
(d) Ringing in the ears
(e) Pulmonary edema
(f) Acid-base disturbances
iv. Ingestion of 300 mg/kg (severe toxicity) may produce:
(a) Metabolic acidosis
(b) Combined respiratory alkalosis-metabolic acidosis
v. Overdose in children is usually accidental.
(a) Symptoms are mild, and they recover swiftly.
(b) A chronic event is usually more serious in pediatric patients.
vi. Overdose in adults is usually intentional.
(a) A fatal event is possible if patient is unresponsive and presents with:
(1) High fever
(2) Seizures
(3) Cardiac dysrhythmias
c. Assessment and management
i. No antidote is available.
ii. Establish and maintain the airway.
iii. Provide high-concentration supplemental oxygen.
iv. Establish vascular access.
v. Stay alert for signs of respiratory fatigue.
vi. Administer serial boluses of normal saline for hypotension.
vii. Monitor carbon dioxide levels with capnometry.
viii. Administer one dose of activated charcoal if instructed by medical control.
ix. Consult with medical control regarding urine alkalinization with sodium bicarbonate.
x. Transport to an appropriate facility.
5. Acetaminophen
a. Well-tolerated with few side effects
i. Lethality comes from two sources:
(a) Belief that it is not dangerous
(b) Lack of awareness that it is an ingredient in many other preparations
b. Pathophysiology
i. Rapidly absorbed from the GI tract.
ii. Signs and symptoms occur in four distinct stages.
c. Assessment and management
i. Try to accurately estimate the time of ingestion.
ii. Antidote is acetylcysteine.
(a) Ideally should be given less than 8 hours after ingestion
(b) Administered based on lab tests; not a field intervention
iii. Establish and maintain the airway.
iv. Administer high-concentration supplemental oxygen.
v. Establish vascular access.
vi. For recent ingestions, administer activated charcoal after consulting with medical control.
vii. Transport to an appropriate facility.
V. Theophylline
1. Naturally occurring alkaloid found in a variety of plants around the world
a. Belongs to the family of drugs called methylated xanthines
2. Pathophysiology
a. Was used for many years to treat COPD and asthma.
i. Also a potent CNS stimulant.
b. Even in therapeutic doses, can cause:
i. Sinus or atrial tachycardia
ii. Frequent premature atrial contractions
iii. Atrial fibrillation
iv. Atrial flutter
v. Premature ventricular contractions
vi. Ventricular dysrhythmias
c. Small therapeutic window
d. Peak levels are reached within 90-120 minutes after ingestion.
i. Sustained release preparations may take as long as 8 hours
ii. Absorption rate increases if taken on an empty stomach or with large amounts of fluids.
3. Assessment and management
a. Most toxic exposures are unintentional.
b. Effects may range from mild GI distress to life-threatening or fatal cardiac dysrhythmias.
i. Patient can go from asymptomatic to a life-threatening state with little or no warning.
c. Common complaints include:
i. Restlessness
ii. Insomnia
iii. Tremors
iv. Agitation
v. Other signs and symptoms of CNS overstimulation
vi. Cardiac dysrhythmias
d. Prompt intervention is essential.
i. Establish and maintain the airways.
ii. Administer high-flow supplemental oxygen.
iii. Establish vascular access.
iv. Continuously monitor ECG rhythm.
v. Administer activated charcoal after consulting with medical control.
vi. Administer fluid boluses or consider low-dose beta blockers for hypotension per local protocol.
vii. Give adenosine for symptomatic reentry supraventricular tachycardia.
(a) Stay alert for bronchospasm.
viii. Treat dysrhythmias per ACLS.
W. Metals and metalloids
1. Lead
a. Remains the leading cause of chronic metal poisoning
i. Elevated levels may significantly hamper intellectual development in children.
b. Pathophysiology
i. Inorganic lead
(a) Absorption usually occurs via the respiratory or GI tract.
(b) Approximately 90% is stored in the bone.
(c) Eventually makes its way into the blood stream.
(d) Can cross the placental barrier and negatively affect fetal development.
(e) Excretion from the body is slow.
(1) Half-life in bone is estimated at 30 years.
ii. Organic lead (tetraethyl lead)
(a) Exposures often occur in the occupational setting.
(b) Once in the body, metabolizes to inorganic lead and triethyl lead.
(1) Triethyl lead is the primary cause of CNS toxicity.
c. Assessment and management
i. Associated with a long list of signs and symptoms
ii. Identify source of the lead.
iii. Establish and maintain the airway.
iv. Administer high-flow supplemental oxygen.
v. Establish vascular access with a saline or heparin lock.
vi. Do not provide fluid therapy unless hypotension is present.
vii. Transport to an appropriate facility.
2. Iron
a. Only a small amount is required as part of a healthy diet.
i. Many multivitamins contain iron.
b. Pathophysiology
i. In the average 70 kg adult, the body’s iron supply consists of about 4 g.
(a) Roughly 65% is found in hemoglobin
(b) Remainder is sequestered elsewhere.
(c) The body of a healthy person does not contain “free” (unbound) iron.
ii. The toxic effects of exposure reflect the amount of elemental iron ingested.
(a) Mild to moderate toxicity: 20 to 60 mg/kg
(b) Severe and potentially lethal toxicity: 60 mg/kg
c. Assessment and management
i. Two broad categories of iron poisoning:
(a) GI toxicity symptoms:
(1) Abdominal pain
(2) Vomiting
(3) Diarrhea
(b) Systemic toxicity symptoms:
(1) Hypotension
(2) Shock
(3) Metabolic acidosis
(4) Tachypneic
ii. Children typically remain asymptomatic with low-level exposure.
(a) Ingestion of a large dose places them at risk of dying unless aggressive and timely interventions take place.
iii. There is little that can be done in the field for iron poisoning.
(a) Provide basic attention to the ABCs.
(b) Transport to an appropriate facility.
3. Mercury
a. In the body, all forms produce toxic effects.
b. Pathophysiology
i. Lipid-soluble and quickly accumulates in the liver, CNS, and kidneys
ii. Can cross the placental membrane into the fetus
c. Assessment
i. Can present differently depending on:
(a) Type of mercury
(b) Route of entry into the body
ii. Most signs and symptoms involve the CNS and GI and renal systems.
iii. CNS alterations may include:
(a) Anxiety
(b) Depression
(c) Irritability
(d) Sleep disturbances
(e) Memory loss
(f) Tremors
(g) Ataxia
(h) Paresthesias
(i) Muscle weakness or rigidity
(j) Excessive drooling
d. Management
i. Remove the patient from the source.
ii. Management is supportive.
(a) Pay basic attention to the ABCs.
(b) Transport to the appropriate facility.
4. Arsenic
a. Most common cause of acute metal poisoning
b. Pathophysiology
i. Can enter the body through:
(a) Ingestion
(b) Inhalation
(c) Absorption
(d) Dermally through a wound
ii. Eliminated through the kidneys
c. Assessment
i. Clinical presentation depends on:
(a) Type
(b) Amount
(c) Concentration
(d) Rate of absorption and elimination
ii. Symptoms generally appear within 30 minutes to several hours of ingestion, and may include:
(a) Severe abdominal pain
(b) Nausea
(c) Explosive diarrhea
(d) Metal taste in the mouth
(e) Skin rash
(f) General malaise
(g) Weakness
(h) Hypotension
(i) Pulmonary edema
(j) Rhabdomyolysis
(k) Renal failure
(l) ECG changes and dysrhythmias
(m) Ventricular tachycardia and torsades de pointes
d. Management
i. Requires aggressive interventions
ii. Establish and maintain the airway.
iii. Administer high-flow supplemental oxygen.
iv. Establish vascular access.
v. Administer sequential boluses of normal saline for hypotension.
(a) Administer a vasopressor or dobutamine if needed.
vi. Continuously monitor the ECG.
(a) Follow ACLS algorithms for dysrhythmias.
vii. Consider 2-4 g of magnesium sulfate for torsades de pointes after consulting with medical control.
viii. Provide rapid transport to an appropriate facility.
ix. British anti-Lewisite and Unitol can be used as chelating agents.
(a) Bind many heavy metals and promote excretion by the body.
(b) Treatment with these agents occurs in a health care setting.
X. Poisonous plants
1. Only a few plant varieties are poisonous.
a. Plant ingestions ranked fourth on the list of most common reasons to contact a Poison Center.
i. Deaths are rare.
2. Pathophysiology
a. Dieffenbachia
i. A green plant with broad, variegated leaves
ii. All parts of the plant contain sharp caladium oxalate crystals.
(a) When ingested, these may cause:
(1) Burns of the mouth and tongue
(2) Paralysis of the vocal cords
(3) Edema of the tongue and larynx leading to airway compromise (severe cases)
b. Caladium
i. Multicolored leaves
ii. Contains caladium oxalate crystals and produces the same results as dieffenbachia
c. Lantana (red sage or wild sage)
i. A perennial flowering shrub with clusters of little red berries
ii. Berries contain lantadene A, which can cause:
(a) Stomach upsets
(b) Muscle weakness
(c) Shock
(d) Death
d. Castor bean
i. Chewing on just a few seeds can kill a child.
ii. Ricin (poison in castor beans) causes a variety of toxic effects:
(a) Burning of the mouth and throat
(b) Nausea
(c) Vomiting
(d) Diarrhea
(e) Severe stomach pains
(f) Prostration
(g) Failing vision
(h) Kidney failure
e. Foxglove
i. Has trumpet-like flowers
ii. Contains cardiac glycosides
iii. Symptoms following ingestion include:
(a) Nausea
(b) Vomiting
(c) Diarrhea
(d) Abdominal cramps
(e) Hyperkalemia
(f) Cardiac dysrhythmias
3. Assessment
a. Get all the information you can from the patient or parent, then contact Poison Center:
i. When was the plant ingested?
(a) Most poisonings produce signs and symptoms of toxicity within 4 hours.
(1) Castor bean may take up to 1 to 3 days after ingestion.
ii. What, exactly, did the child eat?
(a) Includes which type of plant and which part of the plant
(b) Estimate how much was ingested.
(c) If transporting the patient, take the plant with you.
iii. What signs of symptoms, if any, does the child have?
4. Management
a. Most plant-related exposures require no treatment.
b. Contact Poison Center and medical control.
c. Child often can simply remain under parental supervision for 4-6 hours.
d. A child who is symptomatic should be evaluated in the ED.
Y. Poisonous mushrooms
1. Groups who are most likely the victims of mushroom ingestion poisoning include:
a. Wild mushroom pickers
b. People looking for hallucinogenic mushrooms
c. People attempting suicide or homicide
d. Young children who eat them by accident
2. Pathophysiology
a. A variety of factors determine whether a mushroom ingestion will produce toxic results:
i. Age of the mushroom
ii. Season in which the mushroom was gathered
iii. Amount ingested
iv. Preparation method
b. Toxic effects vary from mild GI signs and symptoms to severe cytotoxic effects.
c. In the United States, many deaths involve the Amanita species.
3. Assessment
a. Time of symptom onset can serve as a predictor of potential severity.
i. If within approximately 2 hours, the event is most likely non-life-threatening.
ii. If 6 hours or later, there is a much greater likelihood the event will be potentially fatal.
b. Most common patient complaints include:
i. Abdominal cramping
ii. Watery or bloody diarrhea
iii. Chills or headaches
4. Management
a. Establish and maintain the airway.
b. Establish vascular access.
c. Administer fluid boluses of normal saline for hypotension.
d. Contact the Poison Center and medical control per local protocol.
i. Administer activated charcoal if instructed to do so.
e. Transport to an appropriate facility.
Z. Food poisoning
1. When you encounter two or more people sick at the same time and at the same scene with similar symptoms, think food poisoning or CO poisoning.
a. About 76 million food-related illnesses occur each year.
i. 325,000 require hospitalization.
ii. 5,000 result in death.
2. Pathophysiology
a. Three toxins produce roughly 35% of all food-related deaths:
i. Salmonella
ii. Listeria
iii. Toxoplasma
b. Poisoning with Clostridium botulinum is usually the result of improper food storage or canning.
c. Toxins produced by dinoflagellates in “red tides” may contaminate bivalve shellfish.
i. Cooking does not kill these toxins.
3. Assessment
a. Onset of signs and symptoms can range from several hours to days or weeks.
b. Gastrointestinal complaints are the most common.
i. Hypotension may occur from fluid loss and electrolyte imbalance.
c. Respiratory distress or arrest can occur.
4. Management
a. Establish and maintain the airway.
b. Administer high-flow supplemental oxygen.
c. Establish vascular access.
d. Administer fluid boluses of normal saline for hypotension.
e. Consider administration of diphenhydraine per local protocol for facial flushing.
f. Transport to an appropriate facility.
VIII. Summary
A. Toxicologic emergencies usually fall under one of two general headings: intentional and unintentional.
B. Given the variety of illicit drugs coupled with the continued growth of licit drugs, even the most well-read veteran paramedic may find it difficult to stay current with the myriad drugs sold on the streets today. For this reason, Poison Centers may be an indispensable aid.
C. The four primary methods whereby a toxin commonly enters the body are ingestion, inhalation, injection, and absorption.
D. Although the sheer number of substances of abuse may seem daunting, the good news is that many drugs of similar design, on entering the body, produce similar signs and symptoms as the original parent drug.
E. Human beings have a long history of abusing drugs and alcohol. With the passing of time, the physiologic and societal effects of alcohol abuse have become well known and thoroughly documented. Unfortunately, the area of medicine dealing with drugs of abuse is challenging because of uncertainty about the prevalence of the problem and the continual evolution of the substances themselves.
F. Alcohol is the most widely abused drug in the United States.
G. Generally, patients with toxicologic emergencies are considered medical patients, although toxicologic emergencies may lead to trauma, too.
H. From a management perspective, ALS care for toxicologic emergencies builds on the basics:
1. Ensure the scene is safe for access and egress.
2. Maintain the airway; secure it as needed.
3. Ensure that breathing is adequate.
4. Ensure that circulation is not compromised (by hypoperfusion or dysrhythmia).
5. Maintain adequate blood/oxygen saturations (95%).
6. Establish vascular access.
7. Be prepared to manage shock, coma, seizures, and dysrhythmias.
8. Transport the patient as soon as possible. Place the patient in the left lateral recumbent position if there is any risk of vomiting to reduce the risk of aspiration.
Post-Lecture
This section contains various student-centered end-of-chapter activities designed as enhancements to the instructor’s presentation. As time permits, these activities may be presented in class. They are also designed to be used as homework activities.
Assessment in Action
This activity is designed to assist the student in gaining a further understanding of issues surrounding the provision of prehospital care. The activity incorporates both critical thinking and application of paramedic knowledge.
Instructor Directions
1. Direct students to read the “Assessment in Action” scenario located in the Prep Kit at the end of Chapter 27.
2. Direct students to read and individually answer the quiz questions at the end of the scenario. Allow approximately 10 minutes for this part of the activity. Facilitate a class review and dialogue of the answers, allowing students to correct responses as may be needed. Use the quiz question answers noted below to assist in building this review. Allow approximately 10 minutes for this part of the activity.
3. You may wish to ask students to complete the activity on their own and turn in their answers on a separate piece of paper.
Answers to Assessment in Action Questions
1. Answer: C. The pulse oximeter is accurately measuring the saturation of hemoglobin.
Rationale: A pulse oximeter cannot differentiate between oxygen and other gases that bind to hemoglobin. Carbon monoxide, for example, binds to hemoglobin on the red blood cells (RBCs) about 250 times more readily than do oxygen molecules. The reading is most likely accurate, but do not assume it is a reading for oxygen.
2. Answer: B. poison.
Rationale: A poison is a substance that is toxic by nature, no matter how it gets into the body or in what quantity it is taken. At a minimum, a poison will make people ill; in the worst-case scenario, it will kill them. By contrast, a drug is a substance that has some therapeutic effect (such as reducing inflammation, fighting bacteria, or producing euphoria) when given in the appropriate circumstances and in the appropriate dose.
3. Answer: D. methods of entry.
Rationale: The four primary methods of entry are ingestion, inhalation, injection, and absorption. Just as each of these methods of entry is unique, so is the rate at which a given toxin is absorbed into the body. Once a toxin is in the body, the combination of the amount of toxin and the relative speed at which it is metabolized affect the bioavailability of the toxin and the excretion rate.
4. Answer: A. Correct the patient’s hypoxia with oxygen administration.
Rationale: Correction of hypoxia is a must; therefore, you should administer a high concentration of supplemental oxygen. Establish vascular access; apply an electrocardiographic (ECG) monitor and capnography. Treat the patient, not the assessment tool. This patient has obvious signs of smoke inhalation, at a minimum. Products of combustion contain many toxins other than CO.
5. Answer: D. a toxidrome.
Rationale: The syndrome-like symptoms of a poisonous agent are termed a “toxic syndrome” or “toxidrome.” Toxidromes are useful for remembering the assessment and management of different substances that fall under the same clinical umbrella. The major toxidromes are produced by stimulants, narcotics, cholinergics, anticholinergics, sympathomimetics, and sedatives and hypnotics.
6. Answer: B. synergy.
Rationale: The action of two substances, such as drugs, in which the total effects are greater than the sum of the independent effects of the two substances is known as synergy (that is, 2 + 2 = 5). Two substances that act synergistically, when given or taken together, will produce a stronger response than only one of them given alone.
Additional Questions
7. Rationale: The SLUDGE mnemonic stands for Salivation, Lacrimation, Urination, Defecation, Gastric upset, and Emesis. All of these signs will be present with organophosphate poisoning. Organophosphates are a major component in many insecticides used in agriculture and in the home; they include acephate (Orthene), diazinon (Basudin, Knox Out, Spectracide), and malathion (Celthion, Cythion). Similar-performing compounds are used in chemical warfare.
8. Rationale: Tricyclic antidepressant overdose toxicity comes from inhibition of the sodium and potassium channels within the myocardium. Early signs include the classic anticholinergic signs and symptoms. Late signs include cardiac dysrhythmias, including AV block.
Assignments
A. Review all materials from this lesson and be prepared for a lesson quiz to be administered (date to be determined by instructor).
B. Read Chapter 28, Psychiatric Emergencies, for the next class session.
Unit Assessment Keyed for Instructors
1. Identify the two main categories of toxicological emergencies, and provide examples of each.
Answer: The two categories are intentional and unintentional. Adults with a poisoning emergency are generally considered to be intentional, specifically if suicide has been attempted. Intentional poisonings may also occur during criminal activity such as use of the “date rape” drugs such as flunitrazepam (Rohypnol). Unintentional poisonings are commonly seen in medication or dosing errors, in childhood poisonings involving medications or plants, and in the workplace.
(pp 1325-1326)
2. Describe the four primary methods of toxin entry.
Answer: (1) Ingested poisonings may produce immediate damage to tissues or toxic effects may be delayed for hours. Caustic substances typically produce immediate damage usually as a result of exposure to a strong acid or alkali. Some poisonings such as those caused by medications must be digested and absorbed before effects are seen. Medications and household chemicals are the two most common sources of ingested poisons. (2) Inhaled poisonings occur when the toxic agent is present in the surrounding atmosphere. Remaining in the environment increases exposure and may harm emergency responders who enter the area. Use of an appropriate protective breathing apparatus may be indicated before approaching the patient. Carbon monoxide poisoning may be accidental or intentional. Inhaled toxins will reach the alveoli quickly and can instantly be absorbed into the circulatory system. (3) Injection poisonings are usually the result of stings or bites from insects and animals. It can also include intravenous administration of illicit drugs. Injected poisons may produce neurotixic, localized, or systemic reactions. (4) Absorption poisonings typically occur through the skin. These are most commonly caused by pesticides such as organophosphates and similar substances. They are often the most serious.
(pp 1327-1328)
3. Identify three major toxidromes, and describe symptoms of each.
Answer: Stimulants produce restlessness, agitation, incessant talking, insomnia, anorexia, dilated pupils, tachycardia, tachypnea, hypertension or hypotension, paranoia, seizures, and potentially cardiac arrest. Narcotics (opiates and opioids) produce constricted pupils, marked respiratory depression, drowsiness, stupor, and coma. Needle tracks may also be present. Sympathomimetics produce hypertension, tachycardia, dilated pupils (mydriasis), agitation, seizures, and hyperthermia. Sedative/hypnotics produce drowsiness, disinhibition, ataxia, slurred speech, mental confusion, respiratory depression, progressive central nervous system depression, and hypotension. Cholinergics produce increased salivation, lacrimation, gastrointestinal distress, diarrhea, respiratory depression, apnea, seizures, and coma. Anticholinergics produce dry, flushed skin, hyperthermia, dilated pupils, blurred vision, tachycardia, mild hallucinations, and dramatic delirium.
(p 1329)
4. Describe three potential alcohol-related emergencies.
Answer: Patients may experience severe alcohol intoxication which is a form of poisoning and can be as lethal as other poisonings that depress the central nervous system. Death has occurred with levels of 400 mg/dL with rapid consumption of alcohol. The acutely intoxicated patient is at risk for respiratory depression and/or aspiration from vomitus or stomach contents due to a suppressed gag reflex. Withdrawal seizures can occur in the patient who has consumed alcohol heavily for an extended period of time and suddenly stops. They may occur within 12 to 48 hours of the drink. Delirium tremens (DTs) are serious and potentially lethal complications of alcohol withdrawal. Symptoms may present 48 to 72 hours after alcohol consumption stops.
(pp 1335-1336)
5. Discuss the appropriate management of the patient suffering from stimulant abuse, and identify potentially causative substances.
Answer: Treatment of patients who present with stimulant abuse including cocaine, amphetamines, methamphetamine, and amphetamine-like drugs, as well as bath salts essentially focuses on maintaining maximum oxygen saturation levels, prevention of seizures, and monitoring of vital signs. The airway should be secured and maintained with consideration of placement of an advanced airway as indicated. Supplemental oxygen at high concentrations should be provided. Vascular access should be established with medications available for administration for anxiety, seizure, or violent behavior control. ECG, pulse oximetry, and capnometric monitoring should be done. Hypotension can be managed with fluid administration and hypertension may require contacting of medical control for pharmacological interventions. In some cases, the patient may be hyperthermic and ice packs should be applied to reduce temperature. All patients having a toxicological emergency as a result of a stimulant should be transported to the appropriate facility.
(pp 1336-1337)
6. Discuss the risks associated with two of the four types of cardiac medications that are common for long-term management of cardiovascular disorders.
Answer: Type I antidysrhythmic medications inhibit fast sodium channels within the heart and affect depolorization and impulse conduction. It includes medications such as procainamide (Pronestyl) and lidocaine. Medication overdose may produce myocardial depression, impaired conduction, and decreased contractility. Supportive care should be provided but sodium bicarbonate adminstered IV may be used to help reverse the inhibition of the fast sodium channels in the cardiac cells. Type II antidysrhythmic medications include beta-adrenergic antagonists and beta blockers. Overdosage can result in hypoglycemia, hyperkalemia, and bronchospasm in patients with reactive airway disease. Glucagon given IV is the antidote for toxicity of these medications followed by an infusion. Reconstitution of the glucagon should be done with sterile water to prevent further adverse effects. Severe overdosage may require atropine, epinephrine infusion, and cardiac pacing. Type III antidysrhythmic medications block the potassium channels of the cardiac cells and result in prolonging of the cardiac action potential and an increased effective refractory period. Amiodorone (Cordorone) is an example of this type of medication, and acute toxicity may result in hypotension, bradycardia, or certain ventricular dysrhythmias. Supportive care should be provided, and magnesium sulfate given IV may be adminstered in the presence of torsades de pointes. Type IV antidysrhythmics include the calcium channel blockers. These control pulse rate and blood pressure. Common medications of this type are verapamil and diltiazem (Cardizem). Calcium influx into the cells of the heart, blood vessels, and other smooth muscles is slowed. Toxicity can produce a decreased pulse rate, decreased myocardial contractility, and vasodilation as well as hyperglycemia, nausea/vomiting, altered mental status, and metabolic acidosis. Treamtent includes administration of calcium chloride or calcium gluconate administered IV. Glucogon administration may also be indicated, as well as epinephrine infusions depending on severity of symptoms.
(pp 1342-1343)
7. Identify two common caustic substances in the acids and alkaline groups. Discuss primary concerns associated with managing the caustic substance emergency patient.
Answer: Examples of substances in the acids group include: hydrochloric acids found in many toilet bowl or swimming pool cleaners; sulfuric acid found in battery acid or toilet bowl cleaners; and others such as bleach disinfectants or slate cleaners. Examples of substances in the alkalis group include: lye found in paint removers, washing powders, drain cleaners, button batteries, and Clinitest tablets; sodium hypochlorite found in Clorox bleach; sodium carbonate found in Purex bleach and nonphosphate detergents; ammonia found in hair dyes, jewelry cleaners, metal cleaners/polishers, and antirust agents; and potassium permanganate found in electric dishwasher detergents. Caustic substances cause direct injury to the tissues they contact which may include the mucosal membranes of the eyes, nose, mouth, gastrointestinal tract, and respiratory tract. They may be ingested or absorbed. Severe pain, burns, difficulty talking or swallowing in oral ingestions, and hypoperfusion or shock may occur. Respiratory distress is the most concerning problem as the result of soft-tissue swelling of the larynx, epiglottis, and vocal cords. Irrigation of the skin is indicated for dermal exposures. Milk ingestion may be recommended for ingestion exposures, but vomiting should not be induced, nor should neutralization with other substances be attempted. Gastric lavage and activated charcoal administration is also not indicated.
(pp 1347-1348)
8. Discuss the pathophysiology, assessment, and management of the patient who presents with ethylene glycol poisoning.
Answer: Ethylene glycol is particularly dangerous because it has a relatively pleasant taste and is often substituted by alcoholics when the beverage of choice is not available. It is also not unpleasant when accessed by children. As little as 150 mL in the average sized adult can be lethal. It is found in antifreeze, coolants, deicers, polishes, and paints. It is water soluble and can be absorbed rapidly when ingested, within 1 to 4 hours. It is metabolized by the liver and kidneys and produces toxic metabolites that causes development of metabolic acidosis. There are three stages of symptoms: 20 minutes to 12 hours where CNS depression or intoxication may present; 12 to 24 hours when pulmonary edema may develop and in severe cases acute respiratory distress syndrome, congestive heart failure, and cardiovascular collapse; and in 24 to 72 hours when the renal damage becomes evident with flank pain and anuria. Management of this patient is typically supportive until hospital care can be provided to correct the acidosis and potentially provide renal dialysis.
(pp 1350-1351)
9. Identify the body’s systems affected by lead poisoning, signs and symptoms of these patients, and the major cause of mortality and morbidity from lead poisoning.
Answer: Lead poisoning affects the central nervous system producing altered mentation including irritability and mood changes, as well as memory deficits, sleep disturbances, headache, seizures, and ataxia. The gastrointestinal tract is affected and signs and symptoms include abdominal pain, constipation, and diarrhea. Renal insufficiency, hypertension, and gout occurs as a result of the impact on the renal system. Anemia may develop as a result of hematologic impact. The most common cause of mortality and morbidity is encephalopathy.
(p 1357)
10. Describe the pathology of three common poisonous plants and symptoms produced by ingestion.
Answer: Diffenbachia is a green plant with variegated leaes. It is also called “dumb cane” due to the burns caused by caladium oxalate crystals found in the leaves, stems, and roots. These crystals can burn the mouth and tongue and may result in paralysis of the vocal cords. Edema in the tongue and larynx may compromise the patient’s airway. Caladiums have multicolored leaves and also contains the caladium oxalate crystals. Lantana produces clusters of red berries. Both the immature green berries and the red contain a poison, lantadene, which causes stomach upset, muscle weakness, shock, and sometimes death. The castor bean plant has seeds that are highly poisonous and chewing on one to a few may kill a child. Ricin is the poison found in castor beans and it can cause burns in the mouth and throat, nausea/vomiting, diarrhea, severe stomach pain, prostration, failing vision, and kidney failure which usually results in death. Foxglove has a trumpetlike flower which contains cardiac glycosides used to make digitalis. Common symptoms are similar to those found in digitalis toxicity including nausea, vomiting, diarrhea, and abdominal cramps as well as hyperkalemia and cardiac dysrhythmias.
(p 1358)
Unit Assessment
1. Identify the two main categories of toxicological emergencies, and provide examples of each.
2. Describe the four primary methods of toxin entry.
3. Identify three major toxidromes, and describe symptoms of each.
4. Describe three potential alcohol-related emergencies.
5. Discuss the appropriate management of the patient suffering from stimulant abuse, and identify potentially causative substances.
6. Discuss the risks associated with two of the four types of cardiac medications that are common for long-term management of cardiovascular disorders.
7. Identify two common caustic substances in the acids and alkaline groups. Discuss primary concerns associated with managing the caustic substance emergency patient.
8. Discuss the pathophysiology, assessment, and management of the patient who presents with ethylene glycol poisoning.
9. Identify the body’s systems affected by lead poisoning, signs and symptoms of these patients, and the major cause of mortality and morbidity from lead poisoning.
10. Describe the pathology of three common poisonous plants and symptoms produced by ingestion.