Chapter 27 Toxicology 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. National EMS Education Standard Competencies Toxicology − Recognition and management of • Carbon monoxide poisoning • Nerve agent poisoning − How and when to contact a poison control center National EMS Education Standard Competencies Anatomy, physiology, pathophysiology, assessment, and management of − Inhaled poisons − Ingested poisons − − − − Injected poisons Absorbed poisons Alcohol intoxication and withdrawal Opiate toxidrome National EMS Education Standard Competencies Anatomy, physiology epidemiology, pathophysiology, psychosocial impact, presentations, prognosis, and management of the following toxidromes and poisonings − − − − − Cholinergics Anticholinergics Sympathomimetics Sedative/hypnotics Opiates National EMS Education Standard Competencies Anatomy, physiology epidemiology, pathophysiology, psychosocial impact, presentations, prognosis, and management of the following toxidromes and poisonings (cont’d) − Alcohol intoxication and withdrawal − Over-the-counter and prescription medications − Carbon monoxide − Illegal drugs − Herbal preparations Introduction • Paramedics are often called to treat patients who are abusing licit or illicit drugs. © Ed Isaacs/ShutterStock, Inc. © Anne Kitzman/ShutterStock, Inc. © Comstock Images/Getty Images Introduction • Poison − Substance that is toxic by nature, no matter how it gets into the body or how much is taken • Drug − Substance that has a therapeutic effect when given in the appropriate: • Circumstances • Dose Introduction • Bioavailability: extent to which a drug is present in sufficient amounts to produce desired result • Half-life: point when the bioavailability of a given drug has decreased to 50% • Excretion: How a drug is removed from the body Types of Toxicologic Emergencies • Unintentional − Can occur in many ways, including: • Children who mistakenly put poison in their mouths • Intentional − “Overdose” or “intimate crime” Poison Centers • Poison Centers (1-800-222-1222) can provide a rundown on a poison’s: − Ingestion − Toxic potential − Steps to negate effects • Never hesitate to call! Routes of Absorption • Poisoning by ingestion − Immediate damage or delayed effects • What is ingested? • Why was it ingested? © Victoria Short/ShutterStock, Inc. − Generally provides time for identification/treatment − Management: remove or neutralize the poison Routes of Absorption • Poisoning by inhalation − Toxic agent may be present in the environment. • Patient will inhale the toxin as long as he/she remains in the environment. • Likely to find more than one patient − May be accidental or intentional Routes of Absorption • Poisoning by inhalation (cont’d) − Window for identification/treatment is limited. − Consider scene safety. − Look for information to help identify toxin. − Utilize the Poison Center and medical control. − Correct hypoxia. Routes of Absorption • Poisoning by injection − Usually gain access as the result of: • Stings or bites from insects and animals • Abuse of intravenously administered drugs − Possibilities vary by geographic location. Routes of Absorption • Poisoning by injection (cont’d) − Some poisons are neurotoxic; others produce localized or systemic reactions. − Physical findings will provide clues. − The patient may be able to identify the culprit. Routes of Absorption • Poisoning by absorption − Poisonings by pesticides are often the most serious. Understanding and Using Toxidromes • Toxidrome: the syndrome-like symptoms of a class or group of similar poisonous agents Overview of Substance Abuse • Drug abuse: use of drugs that causes harm to the user or to others affected by the user • Habituation: psychological dependence on a drug or drugs Overview of Substance Abuse • Physical dependence: a physiologic state of adaptation to a drug • Psychological dependence: emotional state of craving a drug to maintain well-being • Tolerance: physiologic adaptation to drug effects Overview of Substance Abuse • Withdrawal syndrome: occurs after the abrupt cessation or decrease of a drug • Drug addiction: chronic disorder characterized by the compulsive use of a substance • Antagonist: drug with affinity for a cell receptor Overview of Substance Abuse • Potentiation: enhancement of the effect of one drug by taking it with another drug. • Synergism: action of two substances in which the effects are greater than independent effects Patient Assessment • Toxicologic emergencies are generally considered medical emergencies. • General assessment approach is the same for all patients. Scene Size-Up • Patients who have taken an overdose may be dangerous. − Call for law enforcement or a crisis unit if necessary. Primary Assessment • Form a general impression. • Identify concerns or life threats. • Identify MOI or NOI. • Identify need for additional resources. • Set the priority. History Taking • Use OPQRST and SAMPLE history. • Obtain the following: − What is the agent? − When was it ingested, injected, absorbed, or inhaled? History Taking • Obtain the following (cont’d): − How much was taken, injected, absorbed, or inhaled? − What else was taken? − Has the patient vomited or aspirated? − Why was the substance taken? Secondary Assessment • For trauma, classify as significant or nonsignificant MOI. • Prioritize injuries. • Manage injuries. • Document findings. Reassessment • Monitor patient’s condition. • Reprioritize the status if necessary. • Check interventions. Emergency Medical Care • Ensure scene safety. • Maintain the airway. • Ensure that breathing is adequate. • Ensure that circulation is not compromised. • Administer high-concentration oxygen. Emergency Medical Care • Establish vascular access. • Be prepared to manage shock, coma, seizures, and dysrhythmias. • Transport the patient as soon as possible. Alcohol • Most widely abused drug in the United States • Red flags may include: − Drinking alone or in “secret” − Loss of memory or “blackouts” − “Green tongue syndrome” Alcohol • Pathophysiology − Evolves through two distinct phases: • Problem drinking • Physical dependence − More prone to serious illnesses and injuries Alcohol • Acute alcohol intoxication − Establish and maintain the airway. − Give high concentration oxygen. − Assist ventilations as necessary. − Establish vascular access. Alcohol • Acute alcohol intoxication (cont’d) − Monitor ECG rhythm. − Assess blood glucose level. − Administer thiamine if directed by medical control. − Transport to an appropriate facility. Alcohol • Withdrawal seizures − Occur within 12 to 48 hours of last drink − Use the same care as for alcohol intoxication. − Consider administering benzodiazepines. Alcohol • Delirium tremens − Usually starts 48 to 82 hours after the last drink − Signs and symptoms may include: • Tremors • Diaphoresis • Hallucinations • Hypotension Alcohol • Delirium tremens (cont’d) − Try to keep the patient calm. − Administer supplemental oxygen by nasal cannula. − Establish vascular access. − Check breath sounds. − Maintain an ongoing dialogue. Stimulants • Users may become addicted within days. − Success of overcoming addiction is low. − May be taken orally, smoked, or injected − Clinical presentation may include: • Excitement • Delirium • Dilated pupils Cocaine • Alkaloid extracted from Erythroxylon coca • Pathophysiology − A local anesthetic and a CNS stimulant − Quickly absorbed across mucosal membranes − Crack cocaine: cocaine mixed with baking soda and water that is cooked or baked Cocaine • Pathophysiology (cont’d) − Effects are felt between 8 seconds to 1 minute. − When the effects wear off, the user experiences a “crash.” − Speedballing: use of heroin and cocaine Cocaine • Assessment − Can cause serious complications, including: • Lethal ECG dysrhythmias • Acute myocardial infarction • Pneumomediastinum − Quinidine-like effect on cardiac conduction Amphetamine, Methamphetamine, and Amphetamine-like Drugs • Amphetamines include: − Methamphetamine − Methylenedioxyam phetamine − Methylenedioxymethamphetamine • Have a number of clinical applications © Jones & Bartlett Learning. Photographed by Kimberly Potvin. Amphetamine, Methamphetamine, and Amphetamine-like Drugs • Methamphetamine − Low-cost, long-acting (up to 12 hours) − Ingredients are available locally − Patient management is the same as for cocaine. Bath Salts • Active ingredient is methcathinone • Users typically snort, smoke, or ingest. − More serious side effects include: • Agitation • Hallucinations • Paranoia Management of Stimulant Abuse • Establish and maintain the airway. • Give high-concentration oxygen. • Establish vascular access. • Apply the ECG monitor, pulse oximeter, and capnometer. Management of Stimulant Abuse • Administer benzodiazepines per protocol. • Manage hypotension with serial fluid infusions. • Consider nitroprusside for hypertension. Management of Stimulant Abuse • Consider haloperidol for violent behavior. • Transport to the appropriate facility. • Follow protocols regarding beta blockers. • Apply ice packs to reduce hyperthermia. Management of Stimulant Abuse • Maintain urine output. • Administer benzodiazepines for seizure. • Neuromuscular blockade may be needed. Marijuana and Cannabis Compounds • Derived from Cannabis sativa • Clinical uses: − Treatment of glaucoma − Relief of nausea and appetite loss from chemotherapy © Mitchell Brothers 21st Century Film Group/ShutterStock, Inc. Marijuana and Cannabis Compounds • Pathophysiology − Psychoactive ingredient: delta 9-tetrahydrocannabinol − Usually smoked, but can be ingested − Signs and symptoms may include: • Euphoria • Decreased short-term memory • Bloodshot eyes Marijuana and Cannabis Compounds • Assessment and management − Focus on supportive care. • Spice − A blend of synthetic cannibinoids − Can make people delirious Hallucinogens • Causes some distortion of sense perception − Experience is affected by: • User’s previous drug experience • Dose taken • User’s expectations • Social setting • Classified as synthetic or naturally occurring LSD • Pathophysiology − Primarily affects the senses − Physiologic effects may include: • Mild tachycardia • Mild hypertension • Dilated pupils LSD • Assessment and management − Treatment is primarily supportive. − Limit sensory stimulation as much as possible. Phencyclidine (PCP) • Pathophysiology − Typically smoked or snorted (can be injected) − Small doses can produce symptoms of intoxication. − Hallmarks: • Mind-body separation • Hallucinations • Violent outbreaks Phencyclidine (PCP) • Assessment and management − Try to calm the patient, and address wounds. − Administer high-flow oxygen. − Monitor vital signs. − Provide safe transport. Ketamine • Pathophysiology − Typical oral dosing is 75–300 mg. − At higher doses, user may have: • Pronounced nausea • Difficulty moving • Complaint of “entering another reality” Ketamine • Assessment and management − Secure the patient well. − Assess and manage ABCs. − Provide oxygen therapy. − Establish vascular access. − Provide safe transport. Peyote and Mescaline • Pathophysiology − Profound vomiting often occurs. − Symptoms include: • Dilated pupils • Increased pulse rate • Mild hypertension • Increased body temperature © Martyn Vickery/Alamy Images Peyote and Mescaline • Assessment and management − Pay attention to the ABCs. − Administer supplemental oxygen. − Monitor vital signs. − Provide psychological support. − Arrange safe transport. Psilocybin Mushrooms • Typical dose: 2–4 mushrooms • Pathophysiology − Onset: 30 minutes − Effects last 4–6 hours. − Symptoms may include: • Vomiting • Mydriasis • Mild tachycardia © Elisa Locci/ShutterStock, Inc. Psilocybin Mushrooms • Assessment and management − Pay attention to ABCs. − Monitor vital signs. − Safely transport. − Establish vascular access. Sedative and Hypnotics • Sedative: reduce anxiety and calm agitation • Hypnotic: used as sleeping aids • Function as CNS depressants Barbiturates • Pathophysiology − Four basic configurations: • Long-acting • Intermediate-acting • Short-acting • Ultra-short-acting Barbiturates • Assessment − Mild to moderate barbiturate intoxication presents much like alcohol intoxication. − As dose increases: • Increasingly lethargic • Increasingly lower level of responsiveness Barbiturates • Management − Airway control is the first priority. − Administer high-concentration oxygen. − Monitor ECG rhythm. − Establish venous access. − Use pulse oximetry and capnography. Barbiturates • Management (cont’d) − If shock develops, crystalloids may be needed. − For long-acting barbiturates, administer sodium bicarbonate to alkalinize the urine. − Gastric emptying is not recommended. Barbiturates • Management (cont’d) − Withdrawal syndrome will occur in 24 hours. • Potentially life-threatening signs and symptoms − Prevent seizures and cardiovascular collapse. − Rapid transport is indicated. Benzodiazepines • Pathophysiology − Stimulate the gamma-aminobutyric acid pathways, resulting in: • Sedation • Reduced anxiety • Relaxation of striated muscle Benzodiazepines • Assessment − Single-entity overdose has low morbidity rate − Common clinical effects may include: • Altered mentation • Drowsiness • Slurred speech • General incoordination Benzodiazepines • Management − Assess and manage the airway. − Administer high-concentration oxygen. − Establish vascular access. Benzodiazepines • Management (cont’d) − Apply ECG monitor, pulse oximeter, and capnometer. − Consider administering flumazenil. − Transport to appropriate facility. Narcotics, Opiates, and Opioids • Narcotic: drug that produces sleep or altered mental status • Opiate: natural drugs derived from opium • Opioid: non-opium-derived synthetics Narcotics, Opiates, and Opioids • Pathophysiology − Bind with receptor sites in the brain and tissues − Effects are lessened when taken orally. − A dose of naloxone may not permanently reverse the effects of heroin. Narcotics, Opiates, and Opioids • Assessment − Classic presentation features: • Euphoria • Hypotension • Respiratory depression • Pinpoint pupils − Produce a dreamlike state Narcotics, Opiates, and Opioids • Management − Establish a patent airway and vascular access. • Administer naloxone. − If the patient does not respond to naloxone: • They may have taken a potent synthetic drug. • They may have taken multiple drugs. Cardiac Medications • Pathophysiology − Alter the function or rhythm of the heart − Major classes include: • Antidysrhythmics • Beta blockers • Calcium channel blockers • Cardiac glycosides • Antigiotensin-converting enzyme inhibitors Cardiac Medications • Type I antidysrhythmic medications − Includes procainamide and lidocaine − Affect depolarization and impulse conduction − Treatment of overdose is usually supportive. • In certain instances, IV sodium bicarbonate may be used. Cardiac Medications • Type II antidysrhythmic medications − Used to control pulse rate and blood pressure − High doses of IV glucagon is the antidote. − Atropine, epinephrine infusion, and cardiac pacing may be required in severe cases. Cardiac Medications • Type III antidysrhythmic medications − Cause a prolongation of the cardiac action potential and increase the refractory period − Treatment is primarily supportive. • IV magnesium sulfate may be used. Cardiac Medications • Type IV antidysrhythmic medications − Control pulse rate and blood pressure − Slow calcium influx into cells. − Treated with IV calcium chloride or calcium gluconate Cardiac Medications • Assessment and management − Signs and symptoms vary but may include: • Hypotension • Weakness • Rhythm disturbances • Difficulty breathing Cardiac Medications • Assessment and management (cont’d) − Ensure a patent airway and adequate ventilation. − Administer high-flow supplemental oxygen. − Establish vascular access. − Maintain contact with medical control. Organophosphates • A major component in many insecticides − Include: • Acephate • Diazinon • Malathion • Carbamates • Warfarins • Pyrethrums Organophosphates • Pathophysiology − Exert their effects at junctions of the nerve cells of the autonomic nervous system − Symptoms may include: • Anxiety and restlessness • Dizziness • Tremors Organophosphates • Pathophysiology (cont’d) − Signs and symptoms will usually present within the first 8 hours. − SLUDGE is helpful in diagnosis. Organophosphates • Assessment and management − Decontaminate before initiating care. − Establish and maintain the airway. − Establish vascular access. • Administer atropine IV push. • Administer pralidoxime infused with normal saline. Organophosphates • Assessment and management (cont’d) − Apply the ECG monitor, pulse oximeter, and capnometer. − Immediately transport. Carbon Monoxide • Pathophysiology − Colorless, odorless, tasteless gas − Displaces oxygen, preventing oxygen to tissues • Suffocation at the cellular level Carbon Monoxide • Assessment − Signs and symptoms are variable and vague. − Physical examination may reveal: • Bounding pulses • Dilated pupils • Pallor or cyanosis • Cherry red color of the skin Carbon Monoxide • Management − Provide the highest concentration of oxygen. − Remove the patient from the environment. − Establish and maintain the airway. − Give high-flow supplemental oxygen. Carbon Monoxide • Management (cont’d) − Keep the patient quiet and at rest. − Monitor the ECG rhythm and LOC. − Transport to the appropriate facility. Chlorine Gas • Chlorine compounds are commonly used in the home and in occupational settings. Chlorine Gas • Pathophysiology − Minor exposure may include: • Burning sensation in eyes, nose, and throat • Slight cough − Severe exposure may include: • Cyanosis • Shock • Seizures Chlorine Gas • Assessment and management − Remove all patients from the area and triage. − Deliver high-concentration humidified oxygen. − Irrigate burning or itching eyes and skin. Cyanide • Pathophysiology − Rapid-acting and deadly poison − Combines with cytochrome oxidase, which blocks utilization of oxygen at the cellular level • Death within minutes to an hour if ingested Cyanide • Assessment − Patient may have an altered mental status. − Signs and symptoms may include: • Palpitations • Odor of almonds on the breath • Rapid respirations and pulses • Bright red venous blood and body Cyanide • Management − Should be treated as fast as possible − If cyanide was inhaled: • Remove the patient from the source. • Establish an airway. • Administer 100% supplemental oxygen. • Assist ventilations as needed. Cyanide • Management (cont’d) − Use the cyanide antidote kit. − If unavailable, break amyl nitrite into gauze pad. • Hold over the patient’s nose for about 20 seconds • Allow the patient to breathe a high concentration of oxygen for about 40 seconds. Cyanide • Hydroxocobalamin − A safe alternative or adjunct to traditional treatment − Included in the “Cyanokit” − Allergy/anaphylaxis is the primary concern. Cyanide • Methylene blue − An antidote used to treat methemoglobinemia − Methemoglobinemia: alteration of hemoglobin • Induced by amyl nitrite and sodium nitrite − Administered under the guidance of an expert Caustics • Strong acids and strong alkalis − Mostly involves accidental dermal or ocular exposure Caustics • Severe pain • Burns • Difficulty talking © Jones & Bartlett Learning. Photographed by Kimberly Potvin. − Cause chemical injury to tissues − Signs and symptoms include: Courtesy of Lynn Betts/NRCS • Pathophysiology Caustics • Assessment and management − For caustic ingestion: • Give milk. • Establish vascular access. • Immediate transport is indicated. − For dermal exposure: • Dilute and flush away substance. Caustics • Assessment and management (cont’d) − For eye exposure: • Place the prong section of a nasal cannula on the bridge of the patient’s nose. • Plug in a macro IV administration set, and provide continuous irrigation. Caustics • Assessment and management (cont’d) − DO NOT: • Give any “neutralizing substances.” • Induce vomiting. • Perform gastric lavage. • Give activated charcoal. Common Household Items • May include: − House plants − Pesticides and herbicides − Hydrocarbon products − Glue − Cleaning agents Drugs That Increase Sexual Gratification • Sildenafil (Viagra) − For hypotension, administer normal saline. − For cardiac arrest, follow local protocols. • Marijuana − Supportive care is indicated. Drugs That Increase Sexual Gratification • Cocaine and other stimulant drugs − Administer serial boluses of normal saline. • Amyl nitrite − Hypotension may result. • Ecstasy Drugs That Increase Sexual Gratification • Dextromethorphan − Large doses can lead to: • Hallucinations • Loss of motor control • Dreamlike euphoria Drugs Used to Facilitate Sexual Assault • GHB (Gamma-hydroxybutyrate) − Odorless and colorless liquid, with a salty taste − Exerts its effects within 30 to 60 minutes − Can produce a hypnotic effect Drugs Used to Facilitate Sexual Assault • GHB (cont’d) − Establish and maintain the airway. − Monitor LOC. − Assist breathing and administer oxygen. − Establish vascular access. − Provide rapid transport. Drugs Used to Facilitate Sexual Assault • Rohypnol (roofies) − Potent benzodiazepine − Illegal to make or distribute Methyl Alcohol • Pathophysiology − Formaldehyde and formic acid are responsible for methanol poisoning. − Peak blood levels attained within 30 to 90 minutes. © Jones & Bartlett Learning. Photographed by Kimberly Potvin. © Jones & Bartlett Learning. Photographed by Kimberly Potvin. Methyl Alcohol • Assessment − Symptoms appear 12–18 hours after ingestion: • Nausea and vomiting • Headache or vertigo • Abdominal pain • Blurred vision or blindness Methyl Alcohol • Assessment (cont’d) − Physical exam findings may include: • Altered mental status • Dilated pupils with sluggish or no reaction • Tachypnea • Hypotension Methyl Alcohol • Management − Establish the airway and vascular access. − Assess blood glucose level. − Consider sodium bicarbonate. − Provide immediate transport. − Activated charcoal is contraindicated. Ethylene Glycol • A colorless, odorless liquid − Lethal dose: 2 mL/kg, or as little as 150 mL • Pathophysiology − Water-soluble − Liver and kidneys metabolize into toxic metabolites Ethylene Glycol • Assessment − Stage 1: • CNS depression • Intoxicated appearance • Nausea, vomiting • Seizures • Coma − Stage 2: • • • • • Tachypnea Tachycardia Hypertension Rales CHF − Stage 3: • Renal damage Ethylene Glycol • Management − Care is the same as for methanol poisoning. • May be ordered to administer calcium gluconate Hydrocarbons • Hydrocarbon inhalation − “Bagging” or “huffing” everyday products • “Huffing”: breathing fumes off a soaked rag or towel • “Bagging”: placing a soaked rag or towel into a bag and breathing in the fumes Hydrocarbons • Hydrocarbon inhalation (cont’d) − Remove from the noxious environment. − Administer high-concentration oxygen. − Promptly transport to the appropriate facility. Hydrocarbons Hydrocarbons • Hydrocarbon ingestion − Pathophysiology • Lower the viscosity, higher the risk of aspiration • Low viscosity facilitates the uptake of a hydrocarbon by tissues of the CNS. • Many products cause gastric irritation. Hydrocarbons • Hydrocarbon ingestion (cont’d) − Assessment and management • All symptomatic patients should be transported. • Decontaminate the patient. • Establish and maintain airway and ventilation. • Establish vascular access. Hydrocarbons • Hydrocarbon ingestion (cont’d) − Assessment and management (cont’d) • Continuously monitor the ECG rhythm. • Administer sequential infusions of normal saline. • Transport the patient to the most appropriate facility. Hydrofluoric Acid/ Hydrogen Fluoride • Pathophysiology − Toxicity from an extremely small amount − Leaches calcium and magnesium from body: • Profound hypocalcemia and hypomagnesemia • A massive release of sequestered potassium Hydrofluoric Acid/ Hydrogen Fluoride • Pathophysiology (cont’d) − Inhalation causes: • • • • Bronchospasm Local airway injury Wheezes, rhonchi Pneumonitis or pulmonary edema − Ingestion causes: • • • • Vomiting Abdominal pain Gastritis Profound systemic toxicity Hydrofluoric Acid/ Hydrogen Fluoride • Assessment and management − Manage the ABCs. − For ingestion, provide stomach evacuation. − Administer a calcium- or magnesium-containing substance. Hydrogen Sulfide • Pathophysiology − Highly toxic, colorless gas, with rotten-egg odor − Poisoning usually occurs by inhalation. − Affects all organs, but has the most impact on the lungs and CNS. Hydrogen Sulfide • Pathophysiology (cont’d) − Low-level exposure can cause: • Eye, nose, and throat irritation • Headache • Bronchitis − Very high exposure can cause: • • • • Seizures Shock Coma Cardiopulmonary arrest Hydrogen Sulfide • Assessment and management − No proven antidote. − Remove patient from the contaminated area. − Management is largely supportive. Oxides of Nitrogen • Includes nitric oxide and nitrogen dioxide • Pathophysiology − Exposure can result in: • Irritation of the throat and upper respiratory tract • Buildup of fluid in the lungs • Difficulty breathing Oxides of Nitrogen • Assessment and management − Prehospital treatment includes: • Remove patient from environment. • Provide supportive care. • Gain IV access. • Be prepared to intubate. Tricyclic Antidepressants • Pathophysiology − Requires close attention to dosing compliance − Small therapeutic window − Involved in more deaths than any other class of medication Tricyclic Antidepressants • Assessment − Signs and symptoms may include: • Altered mental status • Dysrhythmias • Dilated pupils • Urinary retention • QT prolongation on ECG Adapted from Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD. Tricyclic Antidepressants • Management − Maintain the airway. − Administer high-flow supplemental oxygen. − Establish vascular access. − Provide continuous ECG monitoring. Tricyclic Antidepressants • Management (cont’d) − Consider activated charcoal and sodium bicarbonate. − Manage hypotension with normal saline. − Assess blood glucose levels. Tricyclic Antidepressants • Management (cont’d) − Seizures: consider benzodiazepines and intubation. − Provide rapid transport. Monoamine Oxidase Inhibitors • Pathophysiology − Increase norepinephrine and serotonin levels − Major potential for drug interactions − Tight therapeutic window − Can precipitate a hypertensive crisis if taken with tyramine-containing foods Monoamine Oxidase Inhibitors • Assessment − Symptoms are often delayed 6–12 hours or more following ingestion. − Prepare to manage a life-threatening event. Monoamine Oxidase Inhibitors • Assessment (cont’d) − Early signs and symptoms include: • • • • Hyperactivity Dysrhythmias Hyperventilation Nystagmus − With a severe overdose, expect: • • • • • Bradycardia Hypotension Seizures Pulmonary edema Cardiac arrest Monoamine Oxidase Inhibitors • Management − No antidote available for overdose − Establish and maintain the airway. − Administer high-flow supplemental oxygen. − Establish large-bore vascular access. − Monitor the ECG rhythm. Monoamine Oxidase Inhibitors • Management (cont’d) − Consider activated charcoal. − Treat hypotension with normal saline. − If seizures occur, treat with benzodiazepines. − If hypertensive, consider phentolamine Selective Serotonin Reuptake Inhibitors • Pathophysiology − Have a larger therapeutic window than MAOIs − Fewer anticholinergic and cardiac effects than TCAs Selective Serotonin Reuptake Inhibitors • Assessment − 50% of patients may be asymptomatic. − Most common symptoms are: • Nausea, vomiting • Dysrhythmias • Sedation • Tremors Selective Serotonin Reuptake Inhibitors • Management − Establish and maintain the airway. − Administer high-flow supplemental oxygen. − Establish vascular access. − Provide continuous ECG monitoring. Selective Serotonin Reuptake Inhibitors • Management (cont’d) − Consider activated charcoal and benzodiazepines. − If widening of the QRS, consider sodium bicarbonate administration. − Transport to appropriate facility. Selective Serotonin Reuptake Inhibitors • Serotonin syndrome − Can occur with drugs that increase central serotonin neurotransmission − Difficult to diagnosis • Lower muscle rigidity is one of the few classic signs. − Primary treatment is to discontinue therapy. Lithium • Pathophysiology − Almost completely absorbed in the GI tract roughly 8 hours after ingestion − High risk of toxic levels and overdose Lithium • Assessment − Early signs and symptoms: • • • • • Nausea Vomiting Hand tremors Excessive thirst Slurred speech − Increased toxicity: • • • • • • Ataxia Muscle weakness Incoordination Blurred vision Hyperreflexia Seizures and coma Lithium • Management − Establish and maintain the airway. − Establish vascular access and treat hypotension. − Maintain continuous ECG monitoring. − Transport to appropriate facility. Nonprescription Pain Medications • Pathophysiology − NSAIDS are rapidly absorbed from the GI tract before being eliminated. − Half-lives vary widely. − Most problems involve long-term use. Nonprescription Pain Medications • Assessment − Signs and symptoms may include: • Altered mentation • Seizures • Hypotension • Nausea, vomiting − Many patients remain asymptomatic. Nonprescription Pain Medications • Management − Establish the airway and vascular access. − Treat hypotension with normal saline. − Treat seizures with benzodiazepines. − Transport to appropriate facility. Salicylates • Pathophysiology − Clinical presentation can change based on: • Patient’s age • Dose ingested • Duration of exposure − Overdose in children is usually accidental. − Overdose in adults is usually intentional. Salicylates • Assessment and management − Establish the airway and vascular access. − Administer normal saline for hypotension. − Monitor carbon dioxide levels. − Administer activated charcoal if instructed. − Transport to an appropriate facility. Acetaminophen • Well-tolerated with few side effects • Pathophysiology − Rapidly absorbed from the GI tract. − Signs and symptoms occur in four distinct stages. Acetaminophen • Assessment and management − Try to accurately estimate the time of ingestion. − Antidote is acetylcysteine. − Establish the airway and vascular access. Acetaminophen • Assessment and management (cont’d) − For recent ingestions, administer activated charcoal. − Transport to an appropriate facility. Theophylline • Pathophysiology − Even in therapeutic doses, can cause: • Sinus or atrial tachycardia • Frequent premature atrial contractions • Atrial fibrillation • Atrial flutter • Premature ventricular contractions • Ventricular dysrhythmias Theophylline • Pathophysiology (cont’d) − Small therapeutic window − Peak levels are reached within 90–120 minutes. Theophylline • Assessment and management − Common complaints include: • Restlessness, insomnia • Tremors • Agitation • Cardiac dysrhythmias Theophylline • Assessment and management − Establish the airway and vascular access. − Continuously monitor ECG rhythm. − Administer activated charcoal, and treat hypotension. − Give adenosine for symptomatic reentry supraventricular tachycardia. Lead • Pathophysiology − Inorganic lead • Absorption usually occurs via respiratory or GI tract. • Excretion from the body is slow. − Organic lead (tetraethyl lead) • Once in the body, metabolizes to inorganic lead and triethyl lead Lead • Assessment and management − Identify source. − Establish the airway and vascular access. − Transport to an appropriate facility. Iron • Pathophysiology − Toxic effects reflect the amount ingested. • Mild to moderate toxicity: 20 to 60 mg/kg • Severe and potentially lethal toxicity: 60 mg/kg Iron • Assessment and management − Two broad categories of iron poisoning: • GI toxicity symptoms • Systemic toxicity symptoms − Provide basic attention to the ABCs. − Transport to an appropriate facility. Mercury • Pathophysiology − Accumulates in: • Liver • CNS • Kidneys • Assessment − Depends on: • Type of mercury • Route of entry − Involves: • CNS • GI/renal systems Mercury • Management − Remove the patient from the source. − Pay basic attention to the ABCs. − Transport to the appropriate facility. Arsenic • Pathophysiology − Can enter the body through: • Ingestion • Inhalation • Absorption • Dermally − Eliminated through the kidneys Arsenic • Assessment − Clinical presentation depends on: • Type • Amount • Concentration • Rate of absorption and elimination Arsenic • Assessment − Symptoms appear within 30 minutes to several hours, and may include: • Severe abdominal pain • Metal taste in the mouth • General malaise • Hypotension • Rhabdomyolysis Arsenic • Management − Establish the airway and vascular access. − Administer normal saline for hypotension. − Continuously monitor the ECG. Arsenic • Management (cont’d) − Consider magnesium sulfate for torsades de pointes. − Provide rapid transport to an appropriate facility. Poisonous Plants • Only a few plants are poisonous. Poisonous Plants Poisonous Plants • Pathophysiology − Dieffenbachia • All parts contain sharp caladium oxalate crystals. − Caladium • Contains caladium oxalate crystals © Hatem Eldoronki/ShutterStock, Inc. © Andriy Doriy/ShutterStock, Inc Poisonous Plants • Pathophysiology (cont’d) − Lantana • Berries contain lantadene A. − Castor bean • Ricin causes a variety of toxic effects. Courtesy of Brian Prechtel/USDA © MaxFX/ShutterStock, Inc. Poisonous Plants • Pathophysiology (cont’d) − Foxglove • Contains cardiac glycosides © Jean Ann Fitzhugh/ShutterStock, Inc. Poisonous Plants • Assessment − Get all the information you can and then contact the Poison Center. • When was the plant ingested? • What, exactly, did the child eat? • What signs of symptoms does the child have? Poisonous Plants • Management − Most exposures require no treatment. − Contact Poison Center and medical control. − A child who is symptomatic should be evaluated in the ED. Poisonous Mushrooms • Pathophysiology • Age of the mushroom • Season gathered © paul prescott/ShutterStock, Inc. • Amount ingested • Preparation method © Ivor Toms/Alamy Images − Factors that determine toxic results: Poisonous Mushrooms • Assessment − Time of symptom onset can serve as a predictor of potential severity. • Within 2 hours: typically non-life-threatening • 6 hours or later: potentially fatal Poisonous Mushrooms • Management − Establish the airway and vascular access. − Administer normal saline for hypotension. − Contact the Poison Center and medical control. − Transport to an appropriate facility. Food Poisoning • When you encounter two or more people sick at the same time and at the same scene, think food poisoning or CO poisoning. Food Poisoning • Pathophysiology − Toxins that produce food-related deaths: • Salmonella • Listeria • Toxoplasma Food Poisoning • Assessment − Onset of signs and symptoms can range from several hours to days or weeks. − Gastrointestinal complaints are the most common. − Respiratory distress or arrest can occur. Food Poisoning • Management − Establish the airway and vascular access. − Administer normal saline for hypotension. − Consider diphenhydramine for facial flushing. − Transport to an appropriate facility. Summary • Toxicologic emergencies usually fall under one of two general headings: intentional and unintentional. • Poison Centers may be an indispensable aid. • The four primary methods whereby a toxin commonly enters the body are ingestion, inhalation, injection, and absorption. Summary • Many drugs of similar design, on entering the body, produce similar signs and symptoms as the original parent drug. • 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. Summary • Alcohol is the most widely abused drug in the United States. • Generally, patients with toxicologic emergencies are considered medical patients. Summary • ALS care for toxicologic emergencies builds on the basics: − Ensure the scene is safe for access and egress. − Maintain the airway; secure it as needed. − Ensure that breathing is adequate. − Ensure that circulation is not compromised. − Maintain adequate blood/oxygen saturations (95%). − Establish vascular access. − Transport the patient as soon as possible. Credits • Chapter opener: © Mark C. Ide • Backgrounds: Gold—Jones & Bartlett Learning. Courtesy of MIEMSS; Green—Jones & Bartlett Learning; Purple—Jones & Bartlett Learning. Courtesy of MIEMSS; Blue—Courtesy of Rhonda Beck. • Unless otherwise indicated, all photographs and illustrations are under copyright of Jones & Bartlett Learning, courtesy of Maryland Institute for Emergency Medical Services Systems, or have been provided by the American Academy of Orthopaedic Surgeons.