Student Notes Chapter 19: Toxicology 1. Chapter 19. Toxicology

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1 Student Notes Chapter 19: Toxicology 1 Chapter 19 Toxicology Unit Summary After students complete this chapter and the related course work, they will be familiar with the classes of compounds involved in substance abuse and poisonings, the routes by which poisons enter the body, and the signs, symptoms, assessment, and treatment for various poisoning emergencies. National EMS Education Standard Competencies Medicine Applies fundamental knowledge to provide basic emergency care and transportation based on assessment findings for an acutely ill patient. Toxicology Recognition and management of: Carbon monoxide poisoning (pp ) Nerve agent poisoning (p 685) How and when to contact a poison control center (p 671) Anatomy, physiology, pathophysiology, assessment, and management of: Inhaled poisons (pp ) Ingested poisons (pp ) Injected poisons (pp ) Absorbed poisons (pp ) Alcohol intoxication and withdrawal (pp ) Knowledge Objectives 1. Define toxicology, poison, and overdose. (p 669) 2. Describe how poisons enter the body. (pp ) 3. Identify the common signs and symptoms of poisoning. (pp ) 4. Describe the assessment and treatment of the patient with suspected poisoning. (pp ) 5. Describe the assessment and treatment of the patient with a possible overdose. (pp , ) 6. Explain the use of activated charcoal, including indications, contraindications, and the need to obtain approval from medical control before administering it. (pp , ) 7. Identify the main types of specific poisons and their effects, including alcohol, opioids, sedativehypnotic drugs, inhalants, sympathomimetics, marijuana, hallucinogens, anticholinergic agents, and cholinergic agents. (pp )

2 Student Notes Chapter 19: Toxicology 2 8. Describe the assessment and treatment for the patient with suspected food poisoning. (pp ) 9. Describe the assessment and treatment for the patient with suspected plant poisoning. (pp ) 10. Understand the role of airway management in the patient suffering from poisoning or overdose. (p 677) 11. Discuss the use of activated charcoal. (pp , ) Skills Objectives 1. Demonstrate the steps in the assessment and treatment of the patient with suspected poisoning. (pp ) 2. Demonstrate the steps in the assessment and treatment of the patient with suspected overdose. (pp ) 3. Demonstrate the steps required to administer activated charcoal. (pp , ) Lecture I. Introduction A. Each day, we come into contact with things that are potentially poisonous. 1. Almost any substance may be a poison in certain circumstances. 2. Different doses can turn even a remedy into a poison. a. Aspirin is an example. B. Acute poisoning affects 5 million children and adults each year. C. Chronic poisoning is much more common. D. Deaths caused by poisoning are fairly rare. 1. Rates of death as the result of poisoning in children have decreased steadily since the 1960s due to safety caps. 2. Deaths caused by poisoning in adults have been rising. a. Result of drug abuse II. Identifying the Patient and the Poison A. Toxicology is the study of toxic or poisonous substances. 1. A poison is any substance whose chemical action can damage body structures or impair body function. a. Poisons act by changing the normal metabolism of cells or by actually destroying them. b. Poisons may act acutely or chronically. 2. Substance abuse is the misuse of any substance to produce a desired effect. a. A common complication of substance abuse is overdose, when a patient takes a toxic dose of a drug. B. Your primary responsibility to the patient who has been poisoned is to recognize that a poisoning has occurred.

3 Student Notes Chapter 19: Toxicology 3 1. Very small amounts of some poisons can cause considerable damage or death. 2. If you suspect poisoning, notify medical control and begin emergency treatment at once. C. The signs and symptoms of poisoning vary according to the specific agent. 1. The presence of such injuries at the patient s mouth strongly suggests the ingestion (swallowing) of a poison. 2. If possible, ask the patient: a. What substance did you take? b. When did you take it (or become exposed to it)? c. How much did you ingest? d. What actions have been taken? e. How much do you weigh? D. Try to determine the nature of the poison. 1. Look around the immediate area for an overturned bottle, a needle or syringe, scattered pills, chemicals, even an overturned or damaged plant. 2. Place any suspicious material in a plastic bag and take it with you. 3. Containers at the scene can provide critical information, such as: a. Name and concentration of the drug b. Ingredients c. Number of pills originally in the bottle d. Prescribed dose E. If the patient vomits, examine the contents for pill fragments. 1. Wear proper personal protective equipment. 2. Collect the vomitus in a plastic bag so that it can be analyzed at the hospital. III. How Poisons Get Into the Body A. The most important treatment you can generally perform for a poisoning is diluting and/or physically removing the poisonous agent. 1. Most often, you will not be administering a specific antidote because most poisons do not have one. 2. How you provide treatment depends on how the poison got into the patient s body in the first place. 3. The four avenues to consider are: a. Inhalation b. Absorption (surface contact) c. Ingestion d. Injection 4. Injection can be the most worrisome in terms of treatment. a. It is difficult to remove or dilute the poison. 5. All routes of poisoning can be deadly, and each should be thought of as being equally serious. 6. Always contact medical control before you proceed with the treatment of any poisoning victim. B. Inhaled poisons 1. Move the patient into fresh air immediately. 2. The patient may require supplemental oxygen.

4 Student Notes Chapter 19: Toxicology 4 3. Always use a self-contained breathing apparatus to protect yourself from poisonous fumes. 4. Some patients may need decontamination after removal from the toxic environment. a. The patient s clothing should be removed in this process because it may contain trapped gases that can be released, exposing you to the toxin. 5. All patients who have inhaled poison require immediate transport to an emergency department. a. Be prepared to use supplemental oxygen via a nonrebreathing mask and/or ventilatory support with a bagmask device, if necessary. b. Make sure a suctioning unit is available in case the patient vomits. 6. Take containers, bottles, and labels with you when transporting the patient to the hospital. 7. Patients sometimes attempt to commit suicide in a vehicle by leaving the engine running in an enclosed garage. a. The exhaust fumes contain high levels of carbon monoxide that will cause the patient to lose consciousness and eventually stop breathing. b. A recent variation involves using a tightly sealed vehicle as a type of gas chamber. c. When you open the door, you may be overcome as well. d. Contact hazardous materials responders and have them remove the victim. C. Absorbed and surface contact poisons 1. These poisons can affect the patient in many ways. a. Skin damage b. Chemical burns c. Rashes or lesions d. Systemic effects 2. It is important to distinguish between contact burns and contact absorption. 3. Signs and symptoms of absorbed poisoning include: a. A history of exposure b. Liquid or powder on a patient s skin c. Burns d. Itching e. Irritation f. Typical odors of the substance 4. Emergency treatment for a typical contact poisoning includes the following steps: a. Avoid contaminating yourself or others. b. While protecting yourself, remove the substance from the patient as rapidly as possible. 5. Remove all contaminated clothing. 6. Flush and wash the skin. a. When a large amount of material has been spilled on a patient, flood the affected part for at least 20 minutes. b. If the patient has a chemical agent in the eyes, irrigate them quickly and thoroughly for at least 5 to 10 minutes for acid substances and 15 to 20 minutes for alkalis. i. Make sure the fluid runs from the bridge of the nose outward. 7. Many chemical burns occur in an industrial setting. a. Do not try to neutralize substances on the skin with additional chemicals. b. Wash the substance off immediately with plenty of water. c. Obtain material safety data sheets.

5 Student Notes Chapter 19: Toxicology 5 i. Transport them with the patient to the hospital. 8. The only time you should not irrigate the contact area with water is when a patient has been contaminated with a poison that reacts violently with water. a. Brush the chemical off the patient, remove contaminated clothing, and apply a dry dressing to the burn area. b. Wear appropriate protective gloves and the proper protective clothing. c. Provide prompt transport to the emergency department. D. Ingested poisons 1. About 80% of poisoning is by mouth. a. Drugs b. Liquids c. Household cleaners d. Contaminated food e. Plants 2. Ingested poisoning is usually accidental in children and deliberate in adults. 3. Signs and symptoms vary greatly with the: a. Type of poison b. Age of the patient c. Time that has passed since the ingestion 4. Your goal is to rapidly remove as much poison as possible from the gastrointestinal tract. a. Further care will be provided at the emergency department. 5. In the past, syrup of ipecac was used to induce vomiting. a. It is generally not used today because of the danger of inhaling vomitus. 6. Many EMS systems use activated charcoal. a. Activated charcoal comes as a suspension that binds to the poison in the stomach and carries it out of the system. b. It is more effective and safer than syrup of ipecac. 7. You should always immediately assess the airway, breathing, and circulation (ABCs) of every patient who has been poisoned. E. Injected poisons 1. Poisoning by injection is usually the result of drug abuse, such as heroin or cocaine. a. The only other parties likely to have injected a patient with poison are insects and animals. 2. Signs and symptoms can have a multitude of presentations, including: a. Weakness b. Dizziness c. Fever d. Chills e. Unresponsiveness f. Excitability 3. Injected poisons are impossible to dilute or remove because they are usually absorbed quickly into the body or cause intense local tissue destruction. 4. Monitor the airway, provide high-flow oxygen, and be alert for nausea and vomiting. 5. Prompt transport to the emergency department is essential.

6 Student Notes Chapter 19: Toxicology 6 a. Take all containers, bottles, and labels. IV. Patient Assessment A. Scene size-up 1. Scene safety a. A well-trained dispatcher is of great value to determine: i. Number of patients involved ii. Whether additional resources are needed iii. Whether trauma is involved b. If this information is not obtained before your arrival, you must assess the scene thoroughly to ensure your own safety and to determine: i. Nature of illness/mechanism of injury ii. Number of patients involved iii. Need for additional resources iv. Whether spine stabilization is required c. Use the appropriate personal protective equipment to avoid being contaminated. 2. Mechanism of injury/nature of illness a. The dispatcher may give important information about a poisoning call. b. If this information is not obtained before your arrival, look for clues and ask yourself the following questions: i. Are there medication bottles lying around the patient and the scene? If so, is there medication missing that might indicate an overdose? ii. Are there alcoholic beverage containers present? iii. Are there syringes or other drug paraphernalia on the scene? iv. Is there an unpleasant or odd odor in the room? If so, is the scene safe? v. Is there a suspicious odor and/or drug paraphernalia present that may indicate the presence of a drug laboratory? B. Primary assessment 1. Form a general impression. a. Obtain a general impression of the patient. b. Assess his or her level of consciousness. c. Determine any life threats. d. Do not be fooled into thinking that a conscious, alert, and orientated patient is in stable condition. 2. Airway and breathing a. Quickly ensure that the patient has an open airway and adequate ventilation. b. Do not hesitate to begin oxygen therapy. c. Consider inserting an airway adjunct to unresponsive patients. d. Consider the potential for spinal injury. 3. Circulation a. Assess the patient s circulatory status. b. You will find variations depending on the substance involved. c. Assess the pulse and skin condition. 4. Transport decision

7 Student Notes Chapter 19: Toxicology 7 a. A delay on the scene to further assess and treat patients is rarely indicated. b. Consider decontamination of the patient before transport depending on the poison the patient was exposed to. i. Decontamination is especially important when transporting in a helicopter. C. History taking 1. Investigate the chief complaint. a. Obtain the patient s medical history. b. If your patient is responsive, begin with an evaluation of the exposure and the SAMPLE history. c. If the patient is not responsive, attempt to obtain the history from other sources: i. Friends ii. Family members iii. Medical identification jewelry iv. Cards in wallets 2. SAMPLE history a. The SAMPLE history guides you in what to focus on as you continue to assess the patient s complaints. b. In addition to the SAMPLE history, you should ask the following questions: i. What is the substance involved? ii. When did the patient ingest or become exposed to the substance? iii. How much did the patient ingest or what was the level of exposure? iv. Over what period did the patient take the substance? v. Has the patient or a bystander performed any intervention? Has the intervention helped? vi. How much does the patient weigh? D. Secondary assessment 1. The secondary assessment is a more detailed, comprehensive examination of the patient that is used to uncover issues that may have been missed during the primary assessment. 2. Physical examinations a. Focus on the area of the body involved with the poisoning or the route of exposure. b. Once the ABCs have been addressed and managed in the primary assessment, conducting a thorough physical will provide additional information on the exposure. c. A general review of all body systems may help to identify systemic problems. 3. Vital signs a. Many poisons produce no outward indications of the seriousness of the exposure. b. Alterations in the level of consciousness, pulse, respirations, blood pressure, and skin are the more sensitive indicators that something serious is wrong. E. Reassessment 1. Continually reassess the adequacy of the patient s ABCs. 2. Evaluate the effectiveness of interventions you have provided. 3. Repeat the assessment of vital signs: a. Every 15 minutes for a stable patient b. Every 5 minutes, or constantly, for a patient who has consumed a harmful or lethal dose 4. Interventions a. Supporting the ABCs is your most important task. b. Dilute airborne exposures with oxygen.

8 Student Notes Chapter 19: Toxicology 8 c. Remove contact exposures with copious amounts of water unless contraindicated. d. Consider activated charcoal for ingested poisons. e. Contact medical control or a poison center to discuss treatment options. 5. Communication and documentation a. Report as much information as you have about the poison to the hospital. b. If the poisoning or exposure occurred in a work setting, bring, or have the company fax, the material data sheet to the hospital. V. Emergency Medical Care A. Ensure scene safety. 1. Follow standard precautions. 2. Perform external decontamination. B. Remove tablets or fragments from the patient s mouth. C. Wash or brush the poison from the patient s skin. D. Assess and maintain the patient s ABCs. E. Provide oxygen and perform assisted ventilations if necessary. F. If the patient demonstrates signs and symptoms of shock: 1. Place patient in the appropriate position. 2. Keep the patient warm. 3. Provide the patient with supplemental oxygen. 4. Transport the patient promptly to the nearest appropriate hospital. G. If approved by medical control, give activated charcoal. 1. Activated charcoal is not indicated for patients: a. Who have ingested an acid, an alkali, or a petroleum product b. Who have a decreased level of consciousness and cannot protect their airway c. Who are unable to swallow 2. Activated charcoal adsorbs, or sticks, to many commonly ingested poisons, preventing the toxin (poison) from being absorbed into the body by the stomach or intestines. a. You will likely carry plastic bottles of premixed suspension, each containing up to 50 g of activated charcoal. b. Some common trade names are Insta-Char, Actidose, and Liqui-Char. c. The usual dose for an adult or child is 1 g of activated charcoal per kilogram of body weight. i. 25 to 50 g for adults ii to 25 g for children 3. Before you give a patient charcoal, obtain approval from medical control. a. Next, shake the bottle vigorously to mix the suspension. b. You may need to persuade the patient to drink it, but never force it. 4. The major side effect of ingesting activated charcoal is black stools. 5. If the patient has ingested a poison that causes nausea, he or she may vomit after taking activated charcoal.

9 Student Notes Chapter 19: Toxicology 9 VI. Specific Poisons A. Over time, a person who routinely misuses a substance may need increasing amounts of it to achieve the same result. 1. This is called developing a tolerance to the substance. 2. A person with an addiction has an overwhelming desire or need to continue using the substance, at whatever cost, with a tendency to increase the dose. 3. Almost any substances can be abused. B. The importance of safety awareness and standard precautions in caring for victims of drug abuse cannot be stressed enough. 1. Known drug abusers have a fairly high incidence of serious and undiagnosed infections, including HIV and hepatitis. a. These patients may bite, spit, hit, or otherwise injure you. b. Always wear appropriate protective equipment. c. Expect the unexpected, and remember, the drug user, not the drug, can pose the greatest threat. C. Alcohol 1. Alcohol is the most commonly abused drug in the United States. a. It kills more than 200,000 people each year. b. Alcoholism is one of the greatest national health problems, along with heart disease, cancer, and stroke. 2. Alcohol abuse can result in many long-term effects. a. The most common effect is liver damage. i. 90% of heavy drinkers will develop some level of hepatitis. ii. 10% to 20% of alcoholics will develop cirrhosis. b. Other long-term effects include: i. Increased incidence of pancreatitis ii. Development of erosive gastritis iii. Increased risk for breast and colorectal cancer c. Long-term abuse leads to atrophy of the cerebrum, resulting in permanently reduced mental function. d. Alcohol decreases the ability to respond to sexual stimulation. i. Long-term use can lead to impotence and sterility. 3. Alcohol is a powerful CNS depressant. a. It is a sedative substance that decreases activity and excitement. b. It is also a hypnotic, which means it induces sleep. c. In general, alcohol dulls the sense of awareness, slows reflexes, and reduces reaction time. d. It may also cause aggressive and inappropriate behavior and lack of coordination. e. A person who appears intoxicated may have other medical problems as well. i. Look for signs of head trauma, toxic reactions, or uncontrolled diabetes. ii. Severe acute alcohol ingestion may cause hypoglycemia. f. Assume that all intoxicated patients are experiencing a drug overdose and require a thorough examination by a physician. 4. Alcohol potentiates many other drugs and is commonly not the only drug taken. 5. If a patient exhibits signs of serious CNS depression, you must provide respiratory support. a. Depression of the respiratory system can also cause emesis, or vomiting.

10 Student Notes Chapter 19: Toxicology 10 b. The vomiting may be very forceful or even bloody (hematemesis) because large amounts of alcohol irritate the stomach. c. Internal bleeding should also be considered if the patient appears to be in shock. 6. Patients in alcohol withdrawal may experience frightening hallucinations, or delirium tremens (DTs). a. The syndrome is characterized by: i. Agitation and restlessness ii. Fever iii. Sweating iv. Tremors v. Confusion and/or disorientation vi. Delusions and/or hallucinations vii. Seizures b. These conditions may develop if patients no longer have their daily source of alcohol. c. Provide prompt transport. d. Reassure the patient and provide emotional support. D. Opioids 1. Opioids are named for the opium in poppy seeds, the origin of heroin, codeine, and morphine. 2. Synthetic opioids include meperidine (Demerol), hydromorphone (Dilaudid), and oxycodone hydrochloride (OxyContin). a. Many addicts may have started using many of the opioids with an appropriate medical prescription. 3. These agents are CNS depressants and can cause severe respiratory depression. a. Tolerance develops quickly, so some users may require massive doses to experience the same high. b. These drugs often cause nausea and vomiting and may lead to the development of hypotension. c. Although seizures are uncommon, they can occur. d. Patients typically appear sedated or unconscious and cyanotic with pinpoint pupils. i. Pinpoint pupils are the most commonly accepted sign of opiate abuse. 4. Treatment includes supporting the airway and breathing. a. Always open the airway, give supplemental oxygen, and be prepared for vomiting. b. Do not attempt any home remedies (eg, applying ice to the groin, forcing milk into the mouth). c. Be aware that someone else may have attempted inappropriate methods of resuscitation. d. The only effective antidote is certain narcotic antagonists such as naloxone (Narcan). i. Patients will respond within 2 minutes when given intravenously. ii. Naloxone is usually administered by paramedics or by physicians. E. Sedative-hypnotic drugs 1. Barbiturates and benzodiazepines are easy to obtain and relatively cheap. a. These drugs are CNS depressants and alter the level of consciousness, with effects similar to those of alcohol. i. The patient may appear drowsy, peaceful, or intoxicated. 2. In general, these agents are taken by mouth. a. Occasionally, the capsules are suspended or dissolved in water and injected. b. Sedative-hypnotic drugs quickly induce tolerance, so the person requires increasingly larger doses. 3. These drugs may also be given to unsuspecting people as a knock-out drink, or Mickey Finn. 4. Generally, your treatment is to provide airway clearance, ventilatory assistance, and prompt transport.

11 Student Notes Chapter 19: Toxicology A benzodiazepine antidote may be administered in the hospital. a. It is called flumazenil and is given intravenously. F. Abused inhalants 1. These agents are inhaled instead of ingested or injected. a. Some of the more common agents include acetone, toluene, xylene, and hexane. b. Found in glues, cleaning compound, paint thinners, and lacquers 2. Gasoline and various halogenated hydrocarbons, such as Freon, used as propellants in aerosol sprays, are also abused as inhalants. a. These are commonly abused by teenagers. b. The effective dose and the lethal dose are very close, making these extremely dangerous drugs. 3. Always use special care in dealing with a patient who may have used inhalants. a. Halogenated hydrocarbon solvents can make the heart hypersensitive to the patient s own adrenaline. b. Even the action of walking may cause a fatal ventricular arrhythmia. 4. Use a stretcher to move the patient, give oxygen, and transport the patient to the hospital. G. Sympathomimetics 1. Sympathomimetics are CNS stimulants that mimic the effects of the sympathetic (fight-or-flight) nervous system. a. These stimulants frequently cause hypertension, tachycardia, and dilated pupils. b. A stimulant is an agent that produces an excited state. 2. Common examples include amphetamines, methamphetamines, crack cocaine, ecstasy, fen-phen, MDA, and speed. a. Designer drugs, such as ecstasy and Eve, are also frequently abused in certain areas of the United States. 3. Cocaine may be taken in a number of different ways. a. It can be absorbed through all mucous membranes and even across the skin. b. The immediate effects of a given dose last less than an hour. c. Smoked crack produces the most rapid means of absorption and, therefore, the most potent effect. 4. Cocaine is one of the most addicting substances known. a. Its immediate effects include excitement and euphoria. b. Acute overdose is a genuine emergency. 5. Be aware that severe agitation can lead to tachycardia and hypertension. a. Patients may be paranoid, placing you at risk. b. Law enforcement officers should restrain the patient if necessary. c. Do not leave the patient unattended during transport. 6. All of these patients need prompt transport because of the risk of seizures, cardiac arrhythmias, and stroke. H. Marijuana 1. Marijuana is abused throughout the world. a. As many as 20 million people use marijuana daily in the United Sates. b. Inhaling marijuana produces euphoria, relaxation, and drowsiness. c. It impairs short-term memory and the capacity to do complex thinking and work. d. The euphoria could progress to depression and confusion. 2. Marijuana use rarely necessitates transport to the hospital. a. The exception is for a patient who is hallucinating, very anxious, or paranoid.

12 Student Notes Chapter 19: Toxicology 12 b. Reassure the patient and transport with a minimum amount of excitement. 3. Marijuana is often used as a vehicle to get other drugs into the body. I. Hallucinogens 1. Hallucinogens alter a person s sensory perceptions. a. The classic hallucinogen is lysergic acid diethylamide (LSD). b. Abuse of PCP is relatively uncommon among young adults. c. Phencyclidine is a dissociative anesthetic that is easily synthesized and highly potent. 2. These agents: a. Cause visual hallucinations b. Intensify vision and hearing c. Generally separate the user from reality 3. Patients experiencing a bad trip will be: a. Hypertensive b. Tachycardic c. Anxious d. Paranoid 4. Your care is the same as that for a patient who has taken a sympathomimetic. a. Use a calm, professional manner. b. Provide emotional support. c. Do not use restraints unless you or the patient is in danger of injury. d. Watch the patient carefully throughout transport. e. Provide reassurance and request ALS assistance. J. Anticholinergic agents 1. The classic picture of a person who has taken too much of an anticholinergic medication is hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter. 2. These are medications that have properties that block the parasympathetic nerve. 3. Common drugs include atropine, Benadryl, and Jimson weed. a. With the exception of Jimson weed, these medications usually are not abused drugs. 4. Some tricyclic antidepressants have significant anticholinergic effects. a. Death from these agents can be rapid the patient can go from appearing normal to seizure and death within 30 minutes. b. Transport immediately. c. The seizures and arrhythmias are best treated in the hospital. K. Cholinergic agents 1. These include nerve gases designed for chemical warfare, insecticides, and some types of wild mushrooms. a. These agents overstimulate normal body functions that are controlled by the parasympathetic nerves, resulting in: i. Salivation ii. Mucus secretion iii. Urination iv. Crying v. An abnormal heart rate

13 Student Notes Chapter 19: Toxicology The signs and symptoms of cholinergic drug poisoning are easy to remember with the mnemonic DUMBELS: a. Defecation b. Urination c. Miosis (constriction of the pupils) d. Bronchorrhea (discharge of mucus from the lungs) e. Emesis f. Lacrimation (tearing) g. Salivation 3. Alternatively, you can use the mnemonic SLUDGE: a. Salivation b. Lacrimation c. Urination d. Defecation e. GI (gastrointestinal) irritation f. Eye constriction/emesis 4. The most important consideration is to avoid exposure yourself. a. Decontamination may take priority over immediate transport. b. Your priorities after decontamination are to: i. Decrease the secretions in the mouth and trachea. ii. Provide airway support. 5. Antidote kits may be available. a. The most common of these antidotes are the Mark I kit and the DuoDote kit. b. Indications include a known exposure to nerve agents or organophosphates with manifestation of signs and symptoms. c. The kit consists of an auto-injector of atropine and one of 2-PAM chloride. L. Miscellaneous drugs 1. Accidental or intentional overdose with cardiac medications has become common. a. Children may ingest them thinking they are candy. b. Signs and symptoms depend on the medication ingested. c. Contacting the poison center as soon as possible is important. d. It is likely you will be given an order to administer activated charcoal. 2. Aspirin poisoning remains a potentially lethal condition. a. Ingesting too many may result in: i. Nausea ii. Vomiting iii. Hyperventilation iv. Ringing in the ears b. Patients with this problem are frequently: i. Anxious ii. Confused iii. Tachypneic iv. Hyperthermic v. In danger of having seizures

14 Student Notes Chapter 19: Toxicology Overdosing with acetaminophen is also very common. a. Generally not very toxic b. However, symptoms of an overdose generally do not appear until it is too late. c. Gathering information at the scene is very important. 4. Be extremely careful in dealing with a child who has ingested a poisonous substance. 5. Some alcohols, including methyl alcohol and ethylene glycol, are even more toxic than ethyl alcohol (drinking alcohol). a. Both will cause severe tachypnea, blindness, renal failure, and eventually death. b. Immediate transport to the emergency department is essential. VII. Food Poisoning A. Food poisoning is almost always caused by eating food contaminated by bacteria. B. There are two main types of food poisoning. 1. The organism itself may cause disease. 2. The organism may produce toxins that cause disease. a. A toxin is a poison or harmful substance produced by bacteria, animals, or plants. C. One organism that produces direct effects of food poisoning is the Salmonella bacterium. 1. Salmonellosis is characterized by severe gastrointestinal symptoms within 72 hours of ingestion, including nausea, vomiting, abdominal pain, and diarrhea. 2. Proper cooking kills bacteria, and proper cleanliness in the kitchen prevents the contamination of uncooked foods. D. The more common cause of food poisoning is the ingestion of powerful toxins produced by bacteria, often in leftovers. 1. The bacterium Staphylococcus is quick to grow and produce toxins in food. 2. Foods prepared with mayonnaise, when left unrefrigerated, are a common vehicle. 3. Results in sudden GI symptoms, including nausea, vomiting, and diarrhea 4. Symptoms usually start within 2 to 3 hours after ingestion or as long as 8 to 12 hours after ingestion. E. The most severe form of toxin ingestion is botulism. 1. Botulism can result from eating improperly canned food. a. The spores of Clostridium bacteria grow and produce a toxin. 2. The symptoms are neurologic. a. Blurring of vision b. Weakness c. Difficulty in speaking and breathing 3. Often fatal, symptoms may develop within the first 24 hours after ingestion or as long as 4 days later. F. In general, you should not try to determine the specific cause of acute gastrointestinal problems. 1. Gather as much history as possible from the patient. 2. Transport him or her promptly to the hospital. 3. When two or more persons in one group have the same illness, you should take along some of the suspected food.

15 Student Notes Chapter 19: Toxicology 15 VIII. Plant Poisoning A. There are several thousand cases of plant poisoning annually. 1. Many household plants are poisonous if ingested. 2. Some cause skin irritation. 3. Some can affect the circulatory system, the gastrointestinal tract, or the central nervous system. B. It is impossible to memorize every plant and poison, let alone their effects. 1. You can and should do the following: a. Assess the patient s airway and vital signs. b. Notify the regional poison center for assistance in identifying the plant. c. Take the plant to the emergency department. d. Provide prompt transport. C. Irritation of the skin and/or mucous membranes is a problem with the common houseplant called dieffenbachia. 1. Emergency medical treatment includes: a. Maintaining an open airway b. Giving oxygen c. Transporting the patient promptly to the hospital for respiratory support IX. Summary A. Poison acts acutely or chronically to destroy or impair body cells. B. If you believe a patient may have taken a poisonous substance, you should support the ABCs and notify medical control. C. Management also entails collecting any evidence of the type of poison that was used and taking it to the hospital; diluting and physically removing the poisonous agent; providing respiratory support; and transporting the patient promptly to the hospital. D. Emergency treatment may include administration of an antidote, usually at the hospital, if an antidote exists. E. A poison can be introduced into the body by inhalation, absorption, ingestion, or injection. F. It is difficult to remove or dilute injected poisons, a fact that makes these cases especially urgent. G. Always consult medical control before you proceed with the treatment of any poisoning victim. H. Move patients who have inhaled poison into the fresh air; be prepared to use supplemental oxygen via a nonrebreathing mask and/or ventilatory support via a bag-mask device. I. With absorbed or surface contact poisons, be sure to avoid contaminating yourself. You should remove all contaminated substances and clothing from the patient, and flood the affected part. J. Approximately 80% of all poisonings are by ingestion, including plants, contaminated food, and most drugs. In general, activated charcoal should be used in these patients. K. People who abuse a substance can develop a tolerance to it or can develop an addiction. L. The most commonly abused drug in the United States is alcohol. It can depress the central nervous system and can cause respiratory depression. You must support the airway in such cases and be prepared for the patient to vomit.

16 Student Notes Chapter 19: Toxicology 16 M. Opioids, sedative-hypnotic drugs, and abused inhalants can also depress the central nervous system and can cause respiratory depression. N. Take special care with patients who have used inhalants because the drugs may cause seizures or sudden death. O. Sympathomimetics, including cocaine, stimulate the central nervous system, causing hypertension, tachycardia, seizures, and dilated pupils. Patients who have taken these drugs may be paranoid, as may patients who have taken hallucinogens. P. Anticholinergic medications, often taken in suicide attempts, can cause a person to become hot, dry, blind, red-faced, and mentally unbalanced. An overdose of tricyclic antidepressants can lead to cardiac arrhythmias. Q. The symptoms of cholinergic medications can be remembered by using the mnemonic DUMBELS, for excessive Defecation, Urination, Miosis, Bronchorrhea, Emesis, Lacrimation, and Salivation; or SLUDGE, for Salivation, Lacrimation, Urination, Defecation, Gastrointestinal irritation, and Eye constriction/emesis. R. Two main types of food poisoning cause gastrointestinal symptoms. In one, bacteria in the food directly cause disease, such as salmonellosis. In the other, bacteria such as Staphylococcus produce powerful toxins. S. The most severe form of toxin ingestion is botulism. The first neurologic symptoms may appear as late as 4 days after ingestion. T. Plant poisoning can affect the circulatory system, the gastrointestinal system, and the central nervous system. Some plants irritate the skin or mucous membranes and may cause obstruction of the airway.

17 Student Notes Chapter 19: Toxicology 17 Post-Lecture Unit Assessment 1. If an alkaline is in the eye, how long should the eye be irrigated? 2. How do the majority of poisons enter the body? 3. What are the contraindications to the administration of activated charcoal? 4. What is the usual dose of activated charcoal for an adult or child? 5. What does the term tolerance mean? 6. How does alcohol affect the system? 7. What is the medical problem related to opioids that is a concern for responders? 8. Give an example of a sympathomimetic. 9. List the terms for the mnemonic DUMBELS. 10. What organ does acetaminophen overdose damage?

18 Student Notes Chapter 19: Toxicology 18 Knowledge Objectives

19 Student Notes Chapter 19: Toxicology 19 Knowledge Objectives