Chapter 19/ Toxicology/ EMTB

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.

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.

Activated charcoal use

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. 12.5 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.

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.

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. a. Take all containers, bottles, and labels.

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. 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.

Signs and symptoms of absorbed poisoning include:

1. 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. 2. Remove all contaminated clothing. 3. 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.

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 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.

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

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?

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 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.

Plant Poisoning

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.

How Poisons Get into the Body: The most important treatment you can generally perform for a poisoning is diluting and/or physically removing the poisonous agent.

1. Most often, the EMT will not be administering a specific antidote because most poisons do not have one. 2. How the EMT 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 proceeding with any treatment of any poisoning victim.

Inhaled Poisons

1. Move the patient into fresh air immediately. 2. The patient may require supplemental oxygen. 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 bag-mask 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.

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?

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 un refrigerated, 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.

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?

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.

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.

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.

Your primary responsibility to the patient who has been poisoned is to recognize that a poisoning has occurred.

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.

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

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

Uses 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. EMT should always immediately assess the airway, breathing, and circulation (ABCs) of every patient who has been poisoned.

Plant Poisoning

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.

The only time the EMT 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.

Chemical burns occuring 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. i. Transport them with the patient to the hospital.

Signs and symptoms of poison ingestion vary greatly:

a. Type of poison b. Age of the patient c. Time that has passed since the ingestion The goal is to rapidly remove as much poison as possible from the gastrointestinal tract.