Tox 2 Flashcards
What is the primary historical advancement in clinical toxicology?
The evolution of poison control centers.
Poison control centers provide critical information and support in cases of poisoning.
Who typically staffs a poison control center?
Staffing usually includes:
* Medical director (medical toxicologist)
* Administrator or managing director
* Specialists in poison information
* Educators for poison prevention programs.
Each staff member plays a vital role in managing poison-related emergencies.
What does the American Board of Medical Subspecialties offer related to medical toxicology?
A subspecialty certificate in medical toxicology for physicians who complete the certifying examination.
This certification validates the expertise of healthcare professionals in toxicology.
What are the main components of emergency evaluation in poisoning cases?
Assessment and diagnosis of toxicity.
This involves identifying the substance involved and its effects on the patient.
List the treatment procedures in clinical toxicology.
- Supportive care (ABC – Mental status)
- Specific drugs and antidotes
- Decontamination
- Enhanced elimination.
Each procedure plays a critical role in managing poisoning cases.
What does ‘supportive care’ in toxicology consist of?
Airways, Breathing, Circulation, and Altered mental status.
This approach addresses the immediate life-threatening conditions in poisoned patients.
What is the most common factor contributing to death from drug overdose?
Loss of airway-protective reflexes leading to airway obstruction.
This highlights the importance of airway management in overdose cases.
What is the initial treatment for airway obstruction in overdose cases?
Optimize airway position and perform endotracheal intubation if necessary.
Early intervention can prevent further complications.
What are the major complications associated with breathing difficulties in drug overdose?
- Ventilatory failure
- Hypoxia
- Bronchospasm.
These complications can quickly lead to severe morbidity and mortality.
What assessment is crucial for patients experiencing ventilatory failure?
Obtain measurements of arterial blood gases.
This helps determine the adequacy of ventilation and guides treatment decisions.
What should be done if a patient’s pCO2 level is elevated?
Begin assisted ventilation if the pCO2 is > 60 mm Hg.
This indicates significant respiratory distress requiring intervention.
What circulatory defects are common in drug overdose cases?
Bradycardia and atrioventricular (AV) block.
These conditions can lead to hypotension and cardiac arrest.
When should bradycardia or AV block be treated?
Only if the patient is symptomatic (e.g., exhibits signs of syncope or hypotension).
Treatment should be carefully considered to avoid unnecessary interventions.
What specific antidote is used for beta receptor antagonist overdose?
Glucagon.
This antidote counteracts the effects of beta-blockers.
What does QRS interval prolongation in ECG indicate?
Serious poisoning by tricyclic antidepressants or other membrane-depressant drugs.
This finding necessitates urgent medical intervention.
What complications may arise from QRS interval prolongation?
- Hypotension
- AV block
- Seizures.
These complications can significantly worsen the patient’s condition.
What is the treatment for tricyclic antidepressant overdose?
Administer sodium bicarbonate as IV bolus and repeat as needed.
This helps correct metabolic acidosis associated with the overdose.
What factors can cause sinus tachycardia?
- Excessive sympathetic stimulation
- Inhibition of parasympathetic tone
- Reflex response to hypotension or hypoxia.
Understanding the cause is critical for appropriate treatment.
What is the treatment for sympathomimetic-induced tachycardia?
Give IV esmolol.
This medication helps to control the heart rate.
What should be done in case of ventricular tachycardia with a pulse?
Perform CPR if necessary and follow standard guidelines for arrhythmias.
Proper management is critical to prevent deterioration.
What is the recommended treatment for hypotension in a clinical setting?
Empiric therapy with intravenous fluids and low doses of vasopressor drugs (e.g., dopamine).
This approach is often effective in stabilizing blood pressure.
What should be administered to all patients with depressed consciousness?
Concentrated dextrose.
This is crucial for addressing potential hypoglycemia.
What is the initial treatment for comatose patients suspected of hypothermia?
Check and maintain airway, ventilation, and oxygen.
This ensures the patient receives necessary support.
What should be done for patients experiencing hyperthermia due to drug intoxication?
Immediate rapid cooling to prevent death or serious brain damage.
Effective cooling can mitigate severe complications.
What are the signs of generalized seizures?
Loss of consciousness, tongue biting, fecal and urinary incontinence.
Recognizing these signs is essential for timely intervention.
What types of decontaminants are available in clinical toxicology?
- Surface decontamination
- Inhalation
- Gastrointestinal decontamination.
Each type targets specific routes of exposure to toxins.
What should be done for skin exposure to corrosive agents?
Wash exposed areas promptly and remove contaminated clothing.
Quick action can prevent severe skin damage.
What is the procedure for eye irrigation after exposure to corrosive substances?
Flush exposed eyes with copious quantities of tepid tap water or saline.
This helps to minimize injury and prevent permanent damage.
What should be monitored in patients after inhalation injury?
Observe closely for evidence of upper respiratory tract edema.
Early signs include a hoarse voice and stridor, indicating potential airway compromise.
What are early signs and symptoms of airway compromise?
Dyspnea, hypoxemia, tachypnea
These symptoms may indicate progressive airway compromise requiring immediate intervention.
What is the recommended action for patients showing evidence of progressive airway compromise?
Endotracheally intubate
This is critical to prevent complete airway obstruction.
What may result from slower-acting toxins in poisoning cases?
Late-onset non-cardiogenic pulmonary edema
This condition may take several hours to appear after exposure.
What is the effectiveness of emesis and gastric lavage after 60 minutes post-ingestion?
Very little of the ingested dose is removed
Studies indicate that these methods are less effective after significant delays.
Why is ipecac syrup no longer commonly used in emergency departments?
Due to the availability of activated charcoal
Ipecac may only be used in rare cases when medical care is delayed.
What is the effectiveness of gastric lavage for recently ingested liquid substances?
Slightly more effective than ipecac
However, it does not remove undissolved pills reliably.
What is activated charcoal primarily made from?
Adsorbent powdered material from wood pulp
Its high surface area allows it to effectively adsorb toxins.
What is the recommended ratio of charcoal to toxin for effective adsorption?
Approximately 10 to 1
Some toxins may require a higher ratio for effective adsorption.
What is the role of cathartics in gastrointestinal decontamination?
Debate exists regarding their efficacy
Some toxicologists still use them routinely despite limited supporting data.
What is whole-bowel irrigation?
A method using a non-absorbable polyethylene glycol solution
It is designed to wash out intestinal contents effectively.
What is the recommended method for surgical removal of poisons?
When gastric or whole-gut lavage fails
Consultation with a poison control center is advised before proceeding.
What is the primary cause of poisoning with Tricyclic Antidepressants (TCAs)?
Suicidal ingestion
TCAs are a common cause of poisoning, hospitalization, and death.
What should be monitored in patients with TCA overdose?
Temperature, vital signs, ECG
Continuous monitoring is crucial for at least 6 hours post-ingestion.
What is the recommended treatment for patients with QRS interval prolongation in TCA overdose?
Administer sodium bicarbonate 2 mEq/kg IV
Repeat as needed to maintain arterial pH between 7.45 and 7.55.
What should not be routinely administered in TCA poisoning?
Physostigmine
It may worsen conduction disturbances and other complications.
What are common symptoms of anticholinergic drug toxicity?
Dry mouth, warm red skin, mydriasis, tachycardia
Severe cases can lead to coma and death.
What is the emergency treatment for severe anticholinergic toxicity?
Small dose of physostigmine (0.5–1 mg IV)
Caution is necessary due to potential severe side effects.
What is the main treatment for barbiturate poisoning?
Supportive care
No specific antidote exists for barbiturate toxicity.
What is the toxicity threshold for iron ingestion in adults?
60 mg/kg elemental iron
In children, the toxic threshold is about 20-30 mg/kg.
What is the treatment for seriously intoxicated iron poisoning patients?
Administer deferoxamine
Monitor urine for changes indicating chelation of iron.
What is the toxic dose of paracetamol associated with liver injury?
140 mg/kg or 7.5 g within 24 hours
Doses as little as 20-30 tablets can cause severe hepatocellular necrosis.
What antidote should be administered for paracetamol overdose?
N-acetylcysteine (NAC)
It is most effective if started within 8-10 hours of ingestion.
What is the range of toxicity for salicylates?
150-300 mg/kg for mild to moderate poisoning; >300 mg/kg for severe poisoning
Levels >160 mg/dL are usually fatal.
What is the range of toxicity for salicylate ingestion?
Ingestion of 150-300 mg/kg causes mild to moderate poisoning; greater than 300 mg/kg causes severe poisoning and levels > 160 mg/dL are usually fatal.
List some characteristic signs and symptoms of salicylate poisoning.
- Nausea
- Vomiting
- Tinnitus
- Hyperthermia
- Acid-base imbalance
- Respiratory alkalosis (in adults)
- Metabolic acidosis (in children)
- Hyperglycemia (in adults)
- Hypoglycemia (in children)
- Confusion
- Coma
- Seizures
- Hyperventilation
- Non-cardiogenic pulmonary edema
What emergency measures should be taken for salicylate poisoning?
- Maintain open airway
- Assist ventilation if necessary
- Administer supplemental oxygen
- Obtain serial arterial blood gases
What should be administered to treat metabolic acidosis in salicylate poisoning?
Intravenous sodium bicarbonate
True or False: There is a specific antidote for salicylate intoxication.
False
What is the recommended treatment for hypoglycemia in salicylate poisoning?
Administer supplemental glucose
What are some characteristics of ethanol poisoning?
- Nausea
- Vomiting
- Ataxia
- Lethargy
- Seizures
- Coma
- Hypothermia
- Respiratory failure
- Hypoglycemia
What is the blood ethanol level that indicates lethal poisoning?
Exceeding 400 mg%
What is the main treatment approach for acute ethanol intoxication?
Supportive care
What specific treatments should be given for ethanol poisoning?
- Dextrose
- Thiamine
- Naloxone
Fill in the blank: Activated charcoal is not effective for _______.
ethanol
What symptoms are associated with opiate poisoning?
- Pinpoint pupils
- Hypotension
- Bradycardia
- Hyperpyrexia
- Cyclical coma
- Muscle spasm
- Respiratory depression
- Respiratory arrest
What is the primary antidote for opiate overdose?
Naloxone
True or False: Naloxone has a longer duration of action than most opioids.
False
What should be monitored in patients with amphetamine poisoning?
Temperature, vital signs, and ECG for a minimum of 6 hours
What is the treatment for agitation in amphetamine poisoning?
Benzodiazepines
Fill in the blank: For severe amphetamine poisoning, _______ may be used to treat hypertension.
parenteral vasodilator (e.g., Phentolamine or Nitroprusside)
What is the range of toxicity for methanol poisoning?
4 ml of absolute methanol causes blindness; 40 mg% blood methanol is fatal.
List some symptoms of methanol toxicity.
- Nausea
- Vomiting
- Headache
- Metabolic acidosis
- Blurred vision
- Changes in color perception
- Decrease in visual acuity
- Dyspnea
- Tachypnea
What specific drugs can be used as antidotes for methanol poisoning?
- Fomepizole
- Ethanol
What is the treatment for mercury poisoning?
- Oral succimer
- Oral unithiol
- Penicillamine
What is the classic triad of symptoms for chronic mercury poisoning?
- Tremor
- Neuropsychiatric disturbances
- Gingivostomatitis
What is the fatal ingestion level of lead for adults?
500 mg of absorbed lead
List sources of lead exposure.
- Lead pigment paint
- Contaminated acidic foods and beverages
- Folk medicine
- Inhalation of fumes from leaded gasoline
What are the symptoms of organophosphate poisoning?
- Miosis
- Sweating
- Salivation
- Involuntary urination
- Defecation
- Lacrimation
- Bronchospasm
- Wheezing
- Diarrhea
- Tremor
- Seizures
- Bradycardia
- Hypotension
- Urinary incontinence
- Muscular twitching of eyelids and face
What specific treatments are used for organophosphate poisoning?
- Atropine
- Pralidoxime
What is the primary risk associated with petroleum distillate ingestion?
Aspiration pneumonia
What is the treatment for petroleum distillate (hydrocarbon) poisoning?
Basic supportive care for all symptomatic patients
What are the potential consequences of hydrocarbon aspiration?
Highly toxic if aspirated, leading to instant death or aspiration pneumonia.
Aspiration pneumonia can result in chemical pneumonitis.
What should be monitored in symptomatic patients after hydrocarbon exposure?
Arterial blood gases, oximetry, chest x-ray, and ECG.
Admit symptomatic patients to an intensive care setting.
What is the treatment for patients who remain asymptomatic after hydrocarbon exposure for 4-6 hours?
They may be discharged.
If coughing occurs upon arrival, aspiration is likely.
What is the general treatment approach for ingestion of hydrocarbons?
Primarily supportive care, as systemic toxicity is rare.
Less than 5-10 mL is typically swallowed in accidental childhood ingestions.
What specific antidote is used for carbon tetrachloride toxicity?
Acetylcysteine.
Methylene blue is used for methemoglobin formers.
What is the initial treatment for inhalation of caustics and corrosives?
Give supplemental oxygen and closely observe for airway obstruction or pulmonary edema.
Emergency measures are crucial.
What is the estimated adult lethal dose of cyanide?
200 mg.
Cyanide is rapidly absorbed and can be fatal within minutes.
What are the characteristic signs of carbon monoxide poisoning?
Atrial fibrillation, nausea, vomiting, headache, dizziness, memory impairment, convulsions, coma, cerebral edema, death.
CO binds to hemoglobin, forming carboxyhemoglobin.
What is the role of hyperbaric oxygen in carbon monoxide poisoning treatment?
Enhances elimination of CO and reduces half-life to 20-30 minutes.
Useful in severe cases.
What is the mechanism of cyanide toxicity?
Inhibits cellular utilization of oxygen by binding to cytochrome oxidase enzymes.
Hydrogen cyanide gas is produced from burning certain materials.
What should be done immediately after a scorpion sting?
Manage with symptomatic home care, including oral analgesics and cool compresses.
Severe cases may require emergency measures.
What is the most common snake envenomation in the United States?
Rattlesnake bite.
Five families of snakes in the USA are poisonous.
What are the local effects of a rattlesnake bite?
Stinging, burning pain, progressive swelling, erythema, and hemorrhagic blebs.
Local reactions can lead to hypovolemic shock.
What is the treatment for severe envenomations from snake bites?
Supportive care, including maintaining an open airway and monitoring vital signs.
Identification of the snake species is crucial for treatment.
What are the systemic effects of coral snake envenomation?
Nausea, vomiting, confusion, diplopia, dysarthria, muscle fasciculations, generalized weakness, respiratory arrest.
Symptoms may be delayed up to 12 hours.
What specific drugs are included in the cyanide antidote package?
Amyl nitrite, sodium nitrite, and sodium thiosulfate.
Hydroxocobalamin is an alternative antidote.
What should be avoided in the treatment of caustic and corrosive ingestion?
Inducing vomiting or giving pH-neutralizing solutions.
These actions can increase the risk of aspiration.
What is the clinical presentation of a dangerous scorpion sting in children?
Systemic symptoms including hyper-excitability, hypertension, tachycardia, and potentially convulsions, paralysis, and respiratory arrest.
Most serious envenomations occur in children under 10 years.
What should be done if a snake is available?
Attempt to have it identified by a herpetologist
Identification by a specialist can provide crucial information for treatment.
What laboratory studies are useful for snake envenomation?
CBC, platelet count, prothrombin time (PT/INR), fibrin split products, fibrinogen, CPK, urine dipstick for occult blood
These tests help assess the severity of envenomation.
What should be obtained early for severe envenomations with bleeding problems?
Blood type and screen
Early identification is critical for effective management.
What should be monitored if compromised respiratory function is suspected?
Oximetry and arterial blood gases
Monitoring is essential to assess respiratory status.
What emergency measures should be taken for snake bites?
Monitor local swelling, consult an experienced surgeon, provide tetanus prophylaxis, administer antibiotics if infected
These measures are crucial for managing complications.
What systemic effects should be monitored in snake bite victims?
Respiratory muscle weakness, airway patency, and bleeding complications
These effects can be life-threatening if not addressed promptly.
What treatments should be provided for hypotension and rhabdomyolysis?
Intravenous crystalloid fluids and sodium bicarbonate
These treatments help stabilize the patient.
What should be prepared for patients with documented envenomation?
Specific antivenom
Antivenom administration can significantly improve outcomes.
What caution should be taken with antivenom administration?
Life-threatening anaphylactic reactions may occur
Even with a negative skin test, caution is advised.
What first-aid measures are generally ineffective for snake bites?
First-aid measures like cuts over the bite site
These actions may cause additional tissue damage.
What immediate actions should be taken after a snake bite?
Remain calm, remove the victim from the snake, wash the area, remove constricting items, apply ice sparingly
These steps help minimize damage and prepare for transport.
What should not be applied to the bite site?
A tourniquet
Tourniquets can cause more harm than good.
What is the recommendation regarding suctioning the bite site?
Suction devices have not improved outcomes and may increase tissue damage
Mouth suction is not advised.
What enhanced elimination methods are not applicable for snake envenomation?
Dialysis, hemoperfusion, and charcoal administration
These methods do not aid in the treatment of snake bites.
