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Questions and Answers
What is emphasized in the approach to a poisoned patient regardless of the toxin ingested?
What is emphasized in the approach to a poisoned patient regardless of the toxin ingested?
What is the 1st goal in the treatment of acute poisoning?
What is the 1st goal in the treatment of acute poisoning?
What must be measured and charted to judge the progress of intoxication?
What must be measured and charted to judge the progress of intoxication?
What type of agents does clinical toxicology primarily deal with?
What type of agents does clinical toxicology primarily deal with?
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In cases of poisoning, what should be done if the patient appears normal?
In cases of poisoning, what should be done if the patient appears normal?
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What is considered the primary aspect of supportive therapy in cases of poisoning?
What is considered the primary aspect of supportive therapy in cases of poisoning?
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What percentage of poisoning exposures are attributed to prescription and over-the-counter medications?
What percentage of poisoning exposures are attributed to prescription and over-the-counter medications?
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What is the primary consideration when identifying poisoning agents during evaluation?
What is the primary consideration when identifying poisoning agents during evaluation?
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Which action is NOT part of the initial evaluation in case of poisoning?
Which action is NOT part of the initial evaluation in case of poisoning?
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What is the most common serious complication associated with drug overdose?
What is the most common serious complication associated with drug overdose?
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Which fluid is preferred for a hypotensive patient in the context of poisoning management?
Which fluid is preferred for a hypotensive patient in the context of poisoning management?
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During the exposure evaluation of a poisoning case, what should be specifically monitored?
During the exposure evaluation of a poisoning case, what should be specifically monitored?
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What is essential to obtain during definitive care with poisoning?
What is essential to obtain during definitive care with poisoning?
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In cases of seizures due to poisoning, what should be checked if the patient presents with seizures?
In cases of seizures due to poisoning, what should be checked if the patient presents with seizures?
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How should airway obstruction caused by a patient's flaccid tongue be managed during initial evaluation?
How should airway obstruction caused by a patient's flaccid tongue be managed during initial evaluation?
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Which of the following is NOT a step in managing poisoning according to the initial evaluation?
Which of the following is NOT a step in managing poisoning according to the initial evaluation?
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What is the primary purpose of performing a risk assessment in cases of acute poisoning?
What is the primary purpose of performing a risk assessment in cases of acute poisoning?
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Which factor is NOT considered during the risk assessment of an acutely poisoned patient?
Which factor is NOT considered during the risk assessment of an acutely poisoned patient?
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What should be done first to prevent further absorption of poison via dermal exposure?
What should be done first to prevent further absorption of poison via dermal exposure?
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Which vital sign would be least relevant in a neurological examination of an acutely poisoned patient?
Which vital sign would be least relevant in a neurological examination of an acutely poisoned patient?
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When correlating clinical features during risk assessment, which aspect is primarily considered?
When correlating clinical features during risk assessment, which aspect is primarily considered?
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What is a key step in managing poison elimination in an acutely poisoned patient?
What is a key step in managing poison elimination in an acutely poisoned patient?
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Which clinical examination finding would suggest potential poisoning during the initial assessment?
Which clinical examination finding would suggest potential poisoning during the initial assessment?
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How is the clinical progress of a patient with acute poisoning primarily tracked?
How is the clinical progress of a patient with acute poisoning primarily tracked?
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What is the primary purpose of gastric lavage?
What is the primary purpose of gastric lavage?
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Under which circumstances should syrup of ipecac not be used to induce vomiting?
Under which circumstances should syrup of ipecac not be used to induce vomiting?
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What is the indication for the administration of activated charcoal?
What is the indication for the administration of activated charcoal?
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What is a critical contraindication for using activated charcoal?
What is a critical contraindication for using activated charcoal?
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What is a characteristic of osmotic cathartics?
What is a characteristic of osmotic cathartics?
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What should be done for solid corrosives found in the conjunctiva?
What should be done for solid corrosives found in the conjunctiva?
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What is the effect of activated charcoal on the absorption of toxins?
What is the effect of activated charcoal on the absorption of toxins?
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What action is typically taken if emesis is contraindicated?
What action is typically taken if emesis is contraindicated?
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Which of the following is not a contraindication for Whole Bowel Irrigation (WBI)?
Which of the following is not a contraindication for Whole Bowel Irrigation (WBI)?
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What is the primary goal of Whole Bowel Irrigation?
What is the primary goal of Whole Bowel Irrigation?
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Which of the following antidotes acts by competing with the poison for certain receptors?
Which of the following antidotes acts by competing with the poison for certain receptors?
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Which of the following classifications of antidotes involves substances that do not change the nature of poisons?
Which of the following classifications of antidotes involves substances that do not change the nature of poisons?
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What type of antidote is Amyl Nitrite classified as?
What type of antidote is Amyl Nitrite classified as?
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Which antidote is employed to decrease the rate of conversion of poisons into their toxic metabolites?
Which antidote is employed to decrease the rate of conversion of poisons into their toxic metabolites?
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Which of the following is an example of a coating antidote?
Which of the following is an example of a coating antidote?
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What does the physiological classification of antidotes focus on?
What does the physiological classification of antidotes focus on?
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Which strategy is emphasized in the management of poisoned patients?
Which strategy is emphasized in the management of poisoned patients?
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What is the second goal in treating acute poisoning?
What is the second goal in treating acute poisoning?
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What is a core principle of supportive care in the case of poisoning?
What is a core principle of supportive care in the case of poisoning?
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What is a commonly incorrect assumption regarding poisoned patients who appear normal?
What is a commonly incorrect assumption regarding poisoned patients who appear normal?
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Which factor is essential for evaluating a poisoned patient?
Which factor is essential for evaluating a poisoned patient?
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Which method is NOT appropriate for preventing absorption of poison?
Which method is NOT appropriate for preventing absorption of poison?
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What should be primarily monitored to judge the progress of intoxication?
What should be primarily monitored to judge the progress of intoxication?
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In managing poisoning, why is it crucial to recognize that poisoning has occurred?
In managing poisoning, why is it crucial to recognize that poisoning has occurred?
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Which of the following actions is critical for ensuring airway patency in cases of poisoning?
Which of the following actions is critical for ensuring airway patency in cases of poisoning?
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What is the most important action to take if a patient presents with seizures due to poisoning?
What is the most important action to take if a patient presents with seizures due to poisoning?
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During the initial evaluation of a potentially poisoned patient, which vital sign is assessed along with blood pressure?
During the initial evaluation of a potentially poisoned patient, which vital sign is assessed along with blood pressure?
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In the context of exposure evaluation, why is hyperthermia monitored in suspected poisoning cases?
In the context of exposure evaluation, why is hyperthermia monitored in suspected poisoning cases?
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What is a key aspect of management in cases of poisoning when a specific toxin is identified?
What is a key aspect of management in cases of poisoning when a specific toxin is identified?
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Which is an essential step to take when gathering a history for a poisoning case?
Which is an essential step to take when gathering a history for a poisoning case?
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Which of the following factors does NOT play a role in the assessment of potential poisoning?
Which of the following factors does NOT play a role in the assessment of potential poisoning?
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What is a common life-threatening consequence of loss of airway-protective reflexes?
What is a common life-threatening consequence of loss of airway-protective reflexes?
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Which of the following is NOT a classification of antidotes?
Which of the following is NOT a classification of antidotes?
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What is the mechanism by which N-acetylcysteine acts as an antidote?
What is the mechanism by which N-acetylcysteine acts as an antidote?
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Which antidote acts by forming a precipitate with a certain toxin?
Which antidote acts by forming a precipitate with a certain toxin?
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Which of the following conditions would contraindicate Whole Bowel Irrigation?
Which of the following conditions would contraindicate Whole Bowel Irrigation?
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Fomepizole is primarily used to counteract the effects of which type of poison?
Fomepizole is primarily used to counteract the effects of which type of poison?
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Which antidote would be appropriate for a patient with cyanide toxicity?
Which antidote would be appropriate for a patient with cyanide toxicity?
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What is the primary action of physical antidotes?
What is the primary action of physical antidotes?
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What type of antidote is used to bypass the effects of carbon monoxide poisoning?
What type of antidote is used to bypass the effects of carbon monoxide poisoning?
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Which vital sign is least relevant during a neurological examination of an acutely poisoned patient?
Which vital sign is least relevant during a neurological examination of an acutely poisoned patient?
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What is the second step in the five-step risk assessment for managing acutely poisoned patients?
What is the second step in the five-step risk assessment for managing acutely poisoned patients?
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Which of the following is NOT part of the management of poisoning?
Which of the following is NOT part of the management of poisoning?
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Which parameter is critical for correlating a patient's clinical features with risk assessment following poison ingestion?
Which parameter is critical for correlating a patient's clinical features with risk assessment following poison ingestion?
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What is a common characteristic of agents that pose a significant risk during acute poisoning?
What is a common characteristic of agents that pose a significant risk during acute poisoning?
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When evaluating risk factors in a poisoned patient, which of the following is NOT considered?
When evaluating risk factors in a poisoned patient, which of the following is NOT considered?
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Which of the following management strategies is focused on the prevention of further poison absorption?
Which of the following management strategies is focused on the prevention of further poison absorption?
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What aspect of skin examination can provide important clues regarding the type of poisoning?
What aspect of skin examination can provide important clues regarding the type of poisoning?
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What is the recommended method for inducing vomiting in a patient who has ingested poison?
What is the recommended method for inducing vomiting in a patient who has ingested poison?
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Which of the following situations contraindicates the induction of emesis?
Which of the following situations contraindicates the induction of emesis?
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What is the ideal time frame for performing gastric lavage after toxin ingestion?
What is the ideal time frame for performing gastric lavage after toxin ingestion?
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Which of the following is a critical contraindication for administering activated charcoal?
Which of the following is a critical contraindication for administering activated charcoal?
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How does an osmotic cathartic function in the treatment of poisoning?
How does an osmotic cathartic function in the treatment of poisoning?
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What should be done immediately for a patient with solid corrosives in the conjunctiva?
What should be done immediately for a patient with solid corrosives in the conjunctiva?
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Under what circumstances should gastric lavage be considered over emesis?
Under what circumstances should gastric lavage be considered over emesis?
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What is a primary characteristic of activated charcoal in relation to drug and chemical absorption?
What is a primary characteristic of activated charcoal in relation to drug and chemical absorption?
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Study Notes
Clinical Toxicology
- Focuses on the effects of drugs and chemicals on humans and animals.
- Often involves drug overdoses and poisonings.
- Works to determine the substance involved and its amount in the body.
- Typically combines biochemistry, pharmacology, and pathology.
- Deals with the adverse effects of agents such as drugs and chemicals.
Initial Evaluation & Management
- All poisoned patients should be treated as potentially life-threatening.
- The initial approach to poisoned patients should be similar regardless of the toxin.
- This approach is known as routine poison management.
Common Poisoning
- Poisoning can result from exposure to various substances, including household cleaning products and pesticides.
- Prescription and over-the-counter medications account for nearly half of poisoning exposures.
Important Strategies
- "Treat the patient, not the poison."
- Prompt treatment is crucial.
- Supportive therapy is essential.
- Maintain respiration and circulation as a primary focus.
- Judge the progress of intoxication by measuring and charting vital signs and reflexes.
Treatment of Acute Poisoning
- 1st Goal: Keep the concentration of poison as low as possible by preventing absorption and increasing elimination.
- 2nd Goal: Counteract toxicological effects at the effector site, if possible.
Initial Evaluation (ABCDEs)
-
Airway:
- Maintain a patent airway.
- Remove any suspected obstructing material.
- Loss of airway-protective reflexes is the most common cause of death from poisoning.
- Airway obstruction can be caused by flaccid tongue or pulmonary aspiration of gastric contents.
-
Breathing:
- Evaluate respiratory rate and oxygen saturation, if available.
- Supplemental oxygen should be considered if there is no oxygen monitor available and the patient has an elevated respiratory rate.
-
Circulation:
- Prompt assessment of vital signs and hydration status is essential.
- Check blood pressure, pulse rate, and rhythm.
- Begin continuous ECG monitoring.
- Secure venous access.
- Draw blood for routine studies.
- Begin intravenous infusion.
- If the patient is hypotensive, normal saline or another isotonic solution is preferred.
-
Disability (Neurological):
- Decreased level of consciousness is a common complication of drug overdose or poisoning.
- In patients with seizures, check blood sugar levels.
- If blood sugar is < 72 mg/dL, administer 50mL of 50% dextrose IV.
- Treat toxic seizures with IV benzodiazepines.
- Refractory seizures can be treated with barbiturates.
-
Exposure (Evaluation of Temperature):
- Consider the possibility of toxic syndromes associated with hyperthermia.
- High levels of certain drugs can cause significantly elevated body temperature.
Definitive Care with Poisoning
- Identify the poison.
- Obtain an accurate and complete history from sources other than the patient: family, friends, pharmacist, and pill bottles or containers found at the scene.
- Establish the time and amount of ingestion.
Supportive Care and Monitoring
- Acute poisoning is a dynamic illness.
- The patient's condition can fluctuate.
- Repeated examinations and ongoing clinical assessment and management are essential.
Physical Examination
- Provides clues about the ingested drugs.
- Important aspects include:
- Vital signs (PR, RR, BP, temp, O2 saturation if available)
- Neurological exam (pupil size, GCS, mental state, tone, reflexes, clonus, focal signs)
- Skin (color, sweating)
- Dry mouth/salivation, bowel sounds, urinary retention
- Evidence of trauma
Risk Assessment
- Early and accurate risk assessment is key to managing acutely poisoned patients.
- It helps predict the likely clinical course, potential complications, and guides management planning.
Risk Assessment Steps
- Agent(s): Assess whether the ingested agents are likely to cause significant toxicity.
- Dose(s): Calculate the dose taken in mg/kg body weight. Use this information to predict the likelihood of significant toxicity.
- Time since ingestion: Important for determining the likely clinical progress of the patient and guiding management.
- Clinical features and progress: Correlate the patient's clinical features and progress with the dose taken and time since ingestion.
- Patient factors (weight and co-morbidities): Consider individual patient factors that may put the patient at particular risk.
Investigations
- Blood sugar level: Check for hypoglycemia.
- ECG: Look for rate (bradycardia or tachycardia) and rhythm abnormalities.
Management
- Management of poisoning is directed toward:
- Prevention of further poison absorption
- Increasing poison elimination
- Use of an antidote (if appropriate)
Prevention of Further Poison Absorption
-
Dermal Exposure:
- Remove all clothing.
- Wash skin gently with soap and water for at least 30 minutes.
-
Eye Exposure:
- Wash conjunctiva with running water or normal saline for 20 minutes.
- Remove solid corrosives with forceps.
-
GIT Exposure:
- Induction of emesis (if appropriate)
- Gastric lavage
- Activated charcoal
- Cathartics
- Whole bowel irrigation
Induction of Emesis
- Ipecac syrup: A safe method for inducing vomiting.
- Should be given within 30 minutes of poison ingestion.
- Ipecac syrup is no longer routinely used at home.
Emesis Contraindications
- Convulsions
- Corrosives
- Hydrocarbons
- Coma
- Age less than 6 months
Gastric Lavage
- Used in hospitals when emesis fails or is contraindicated.
- Effective in the first 4-6 hours after ingestion.
- Technique:
- An assistant with a suction machine should be available.
- Remove dentures, mucus, and vomitus from the patient's mouth.
- Select the proper tube size according to the patient's age.
Activated Charcoal
- Adsorbs a wide variety of drugs and chemicals.
- Not digested; stays in the GI tract and eliminates the toxin during bowel movements.
- Adult dose is 1 g/kg.
- Indications:
- Within one hour of ingestion
- Patient at risk of significant toxic effects
- Patient NOT at risk of airway compromise
Activated Charcoal Contraindications
- If an oral antidote is given
- Seizures, coma
- Corrosive ingestion
- Agents not bound to activated charcoal: hydrocarbons, alcohols, and corrosives (acids, alkalis)
Cathartics (Laxatives)
- Enhance passage of material through GIT.
- Decrease the time of contact between the poison and the absorptive surfaces of the stomach and intestines.
- Types:
- Osmotic cathartics (increase osmotic pressure in the lumen, e.g., magnesium sulfate)
- Irritant cathartics (increase motility, e.g., castor oil)
- Contraindications:
- GIT hemorrhage
- Recent bowel surgery
- Intestinal obstruction
Whole Bowel Irrigation (WBI)
- Goal: Clean the GIT from non-absorbed ingested toxins.
- Uses polyethylene glycol electrolyte solutions.
- Indications:
- Ingestion of a toxin poorly adsorbed by charcoal.
- Massive drug ingestion.
- Ingestion of sustained-release or enteric-coated preparations.
- Removal of ingested packets of illegal drugs (body packers).
Antidote
- A therapeutic substance used to counteract the toxic action(s) of a specific xenobiotic.
- Classified by mechanism of action:
- Interacts with the poison to form a nontoxic complex that can be excreted: chelators
- Accelerate the detoxification of the poison: N-acetylcysteine, thiosulfate
- Decrease the rate of conversion of the poison into its toxic metabolites: Fomepizole
- Compete with the poison for certain receptors: Naloxone
- Block the receptors through which the toxic effects of the poison are mediated: Atropine
- Bypass the effect of the poison: O2 treatment in CO and cyanide toxicity
- Antibodies to the poison: Digiband, antivenoms
Antidote Classification
- Physical
- Chemical
- Physiological
Physical Antidotes
- Agents used to interfere with poisons through physical properties, not changing their nature.
- Adsorbing: Activated charcoal
- Coating: A mixture of egg and milk coats the mucosa.
- Dissolving: 10% alcohol or glycerine for carbolic acid.
Chemical Antidotes
- Oxidizing: Amyl nitrite used in cyanide toxicity.
- Reducing: Vitamin C used for drugs causing Met-Hb.
- Precipitating: Starch precipitates with iodine.
Clinical Toxicology
- Branch of science focusing on the effects of drugs and chemicals on humans and animals
- Deals with adverse effects of drugs, chemicals, etc.
Initial Evaluation & Management
- Routine poison management should be implemented for all poisoned patients, regardless of the toxin ingested.
Common Poisoning
- Prescription and over-the-counter medications account for almost half of poisoning exposures.
Important Strategies
- Treat the patient, not the poison.
- Supportive therapy is essential to maintain respiration and circulation.
Initial Evaluation (ABCDEs)
- Assesses the patient's overall health and well-being
- Includes airway, breathing, circulation, disability (neurological), and exposure (evaluation of temperature).
Airway
- Keep airways patent and remove any suspicion for obstructing material.
- The most common cause of death from poisoning is loss of airway-protective reflexes leading to airway obstruction.
Breathing
- Evaluate respiratory rate and oxygen saturation.
- Consider supplemental oxygen if there is no oxygen monitor but the patient has an elevated respiratory rate.
Circulation
- Promptly assess vital signs and hydration status.
- Begin continuous ECG monitoring.
- Secure venous access.
- Draw blood for routine studies.
- Begin intravenous infusion.
- Normal saline or another isotonic solution is preferred for hypotensive patients.
Disability (Neurological)
- A decreased level of consciousness is a common complication of drug overdose or poisoning.
- Check blood sugar levels in patients experiencing seizures.
- Administer 50ml of 50% dextrose IV if blood sugar levels are less than 72 mg/dL.
- Treat toxic seizures with IV benzodiazepines.
- Treat seizures refractory to benzodiazepines with barbiturates.
Exposure (Evaluation of Temperature)
- Consider toxic syndromes associated with hyperthermia.
Definitive Care with Poisoning
- Identify the poison
- Obtain accurate detailed history from various sources.
- Establish the time and amount of ingestion.
Supportive Care and Monitoring
- Acute poisoning is dynamic, requiring repeated examinations and ongoing assessment.
Physical Examination
- Provides insight into ingested drugs.
- Important aspects include:
- Vital signs (PR, RR, BP, temp, O2 saturation)
- Neurological exam (Pupil size, Glasgow Coma Scale (GCS), mental state, tone, reflexes, clonus, focal signs)
- Skin (color, sweating absent/present)
- Dry mouth/salivation, bowel sounds, urinary retention
- Evidence of trauma
Risk Assessment
- Key component of managing poisoned patients.
- Enables prediction of clinical course, potential complications, and management planning.
Risk Assessment Steps
- Assess whether the ingested agents are likely to cause significant toxicity.
- Calculate the dose taken per kilogram body weight to predict the likelihood of toxicity.
- Determine the time since ingestion to guide management.
- Correlate clinical features and progress with the dose and time since ingestion.
- Consider individual patient factors.
Investigations
- Blood sugar level
- ECG:
- Rate (Bradycardia or Tachycardia)
- Rhythm
Management
- Management focuses on:
- Prevention of further poison absorption.
- Increasing poison elimination.
- Administering an antidote (if appropriate).
Prevention of Further Poison Absorption
- Dermal Exposure:
- Remove all clothing.
- Wash skin gently with soap and water for at least 30 minutes.
- Eye Exposure:
- Wash conjunctiva with running water or normal saline for 20 minutes.
- Remove solid corrosives with forceps.
- GIT Exposure:
- Induction of emesis.
- Gastric lavage.
- Activated charcoal.
- Cathartics.
- Whole bowel irrigation.
Induction of Emesis
- Safe method for induction of vomiting is ipecac syrup, given within 30 minutes of ingestion.
- Ipecac syrup is no longer used routinely as a poison treatment intervention at home.
Contraindications for Emesis
- Convulsions.
- Corrosives.
- Hydrocarbons.
- Coma.
- Less than 6 months of age.
Gastric Lavage
- Used in hospitals when emesis fails or there is a contraindication.
- Effective in the first 4-6 hours after ingestion.
Technique
- Have an assistant with a suction machine available.
- Remove dentures, mucous, vomitus from the patient's mouth.
- Select the proper tube size based on the patient's age.
Activated Charcoal
- Adsorbs a wide variety of drugs and chemicals.
- It is not digested and remains inside the GI tract.
- Eliminates the toxin through bowel movements.
- Adult dose is 1 gm/kg.
Indications for Activated Charcoal
- Ingestion within one hour of time.
- Patient at risk of significant toxic effects.
- Patient NOT at risk of airway compromise.
Contraindications for Activated Charcoal
- Oral antidote administration.
- Seizures, coma.
- Corrosive ingestion.
- Agents not bound to activated charcoal:
- Hydrocarbons.
- Alcohols.
- Corrosives (acids, alkalis.)
Cathartics (Laxatives)
- Enhance the passage of material through the GIT, decreasing contact time between poison and the absorptive surfaces.
Types of Cathartics
- Osmotic cathartics: increase osmotic pressure in the lumen, such as magnesium sulfate.
- Irritant cathartics: increase motility, such as caster oil.
Contraindications for Cathartics
- GIT hemorrhage.
- Recent bowel surgery.
- Intestinal obstruction.
Whole Bowel Irrigation
- Goal is to cleanse the GIT from non-absorbed ingested toxins.
- Polyethylene glycol electrolyte solutions are used.
Indications for Whole Bowel Irrigation
- Ingestion of a toxin poorly adsorbed by charcoal.
- Ingestion of massive amounts of drugs.
- Ingestion of sustained-release or enteric-coated preparations.
- Removal of ingested packets of illegal drugs.
Antidote
- Therapeutic substance used to counteract the toxic actions of a specific xenobiotic.
- Classified according to mechanism of action:
Types of Antidotes
- Interacts with the poison to form a nontoxic complex that can be excreted: chelators.
- Accelerate the detoxification of the poison: N-acetylcysteine, thiosulfate.
- Decrease the rate of conversion of the poison into its toxic metabolites: Fomepizole.
- Compete with the poison for certain receptors: Naloxone.
- Block receptors through which the toxic effects of the poison are mediated: atropine.
- Bypass the effect of the poison: O2 treatment in CO and cyanide toxicity.
- Antibodies to the poison: digiband, antivenoms.
Antidote Classification by Type
-
Physical Antidotes: Agents used to interfere with poisons through physical properties, not changing their nature.
- Adsorbing: Example: activated charcoal.
- Coating: Example: mixture of egg & milk makes a coat over the mucosa.
- Dissolving: Example: 10% alcohol or glycerine for carbolic acid.
-
Chemical Antidotes:
- Oxidizing: Amyl Nitrite is used in cyanide toxicity.
- Reducing: Vitamin C used for drugs causing Met-Hb.
- Precipitating: Starch, it makes a blue precipitate with iodine.
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Description
This quiz covers the fundamentals of clinical toxicology, including the effects of drugs and chemicals on humans and animals. It addresses initial evaluation and management of poisoned patients and common substances involved in poisoning. Test your knowledge on assessment strategies and treatment approaches.
