Toxicology Flashcards
What signs and symptoms would you expect to see in an ingestion of aminata phalloides/death cap mushrooms
Causes a delayed onset hepatotoxicity 6-10 hours later with sxs of N/V/D, abdominal pain, hematuria, proteinuria, elevated LFTs
What treatments should you consider if you suspect an ingestion of aminata phalloides/death cap mushrooms?
Activated charcoal, n-acetylcysteine (NAC), high dose penicillin vs cephalosporin
What signs and symptoms would you expect with an ingestion of a beta blocker?
N/V, bradycardia, hypotension, dysrrhythmia with qrs widening which can lead to torsades, pulmonary bronchospasm, hypoglycemia, hyperkalemia, seizures, coma
How should you manage a beta blocker ingestion?
- Give judicious fluids b/c the decreased cardiac inotropy is a set up for fluid overload and effective CHF
- Widened qrs=NaHCO3
- Torsdes=magnesium
- Arrhythmia=PALS
- Seizures=benzos
- acutely ingested=activated charcoal; bowel cleanout if known extended release formulation
- antidote is glucagon!
- Due to the potential for sxs to arise 8-12 hrs after ingestion, err on the side of admission!
What are examples of calcium channel blockers?
diltizem, amlodipine, verapamil, nifedipine
- What are vital sign changes with calcium channel blocker ingestion?
- What are physical exam findings/sxs with calcium channel blocker ingestion?
- What are potential changes on EKG?
- What are lab changes seen with calcium channel blocker ingestion?
- Vitals-hypotension, bradycardia
- PE/sxs-N/V, lethargy, seizure, coma
- EKG-AV blockade, sinus arrests/junctional rhythms, tachydysrhythmia, torsades
- Labs-hyperglycemia, metabolic acidosis
How should you manage calcium channel blocker ingestion?
- Give judicious fluids b/c the decreased cardiac inotropy is a set up for fluid overload and effective CHF
- seizures=benzos
- Torsades=magnesium
- Arrhythmia=PALS
- acutely ingested=activated charcoal; bowel cleanout if known extended release formulation
- Give IV calcium chloride or calcium gluconate
- If any signs of myocardial instability give high dose insulin-1 Unit/kg of Regular Insulin prior to infusion of 1 Unit/kg/hr
What lab value helps to differentiate between beta blocker and calcium channel blocker ingestion?
Glucose!
- Beta blocker ingestion=hypoglycemia
- calcium channel blocker ingestion=hyperglycemia
What household products may contain camphor?
Vicks vaporub, mothballs, campho-phenique, camphorated oils
- What are signs and symptoms of camphor ingestion?
- What causes death in these patients?
- N/V, burning of the mouth &/or throat, ataxia, drowsiness, confusion, twitching, seizure, coma.
- Death from CNS depression or respiratory arrest
What household product is ethylene glycol commonly found in?
antifreeze!
What are signs and symptoms of ethylene glycol toxicity?
What will be seen on lab work for ethylene glycol toxicity?
- agitation, seizure, coma, cardiac dysrhythmias, hypotension, kussmaul breathing, respiratory depression
- lab: elevated anion gap metabolic acidosis, calcium crystaluria
What is the treatment of ethylene glycol toxicity?
- Early ingestion-try to competitively inhibit toxin formation by giving IV ethanol or fomepizole
- If toxicities are arising hemodialysis is required
What are the signs and symptoms of lomotil ingestion?
- Opioid intoxication effects-respiratory deppression, miosis, bradycardia, hypotension, paralytic ileus, coma
- Anticholinergic effects-lethargy, agitation, flushing, dryness, paralytic ileus, mydriasis
How do you treat lomotil ingestion?
ABCs and supportive care are mainstays, consider narcan for anti-opioid effects and physostigmine for cholinergic stimulation
What household products contain methyl salicylates?
IcyHot patches, wintergree oil, muscle pain relief creams/ointments
- What are symptoms of methyl salicylate ingestion?
- What can be seen on labwork?
- Early on they cause respiratory alkalosis but can also see metabolic alkalosis 2/2 vomiting, metabolic acidosis, and late onset respiratory acidosis
- Sxs include N/V, CNS edema, tinnitus, lethargy, seizures, coma, and hyperthermia
How should you manage a methyl salicylate ingestion?
- ABCs, supportive care, activated charcoal for early ingestion
- NaHCO3 is the antidote
- Severe cases may require hemodialysis
What are examples of sulfonylureas and what is their mechanism of action?
- glyburide, glipizide
- Oral hypoglycemic agents that act as insulin secretagogues
- What are signs and symptoms of sulfonylurea ingestion?
- What electrolyte abnormality would you see?
- lethargy, agitation, tachycardia, seizure, confusion, diaphoresis,
- hypokalemia
How should you manage sulfonylurea ingestion?
- ABCs, supportive care, activated charcoal early, glucose infusion as needed, benzos for seizure
- Ocreotide can help stabilize pancreatic insulin secretion
What conditions is theophylline commonly used to treat?
asthma, COPD, neonatal apnea
How does theophylline work?
- releases endogenous catecholamines to stimulate beta 1&2 receptors
- blocks adenosine receptors of the CNS–>CNS hyperexcitation and vasoconstriction
What are symptoms of theophylline intoxication?
vomiting, tremor, anxiety, tachycardia, hypokalemia, metabolic acidosis, glucose instability, ventricular dysrhythmia, hypotension, intractable seizures
How is theophylline ingestion managed?
- ABCs, supportive care, benzos for seizures
- activated charcoal can disrupt entero-hepatic circulation
- esmolol can parodoxically help with hypotension by normalizing over-stimulated beta receptors
- Avoid over aggressive tx of hypokalemia as it is actually shifted intracellularly
What are examples of TCAs?
amitriptyline, doxepin, amoxapine
What are signs and symptoms of TCA ingestion?
- ventricular dysrhythmia, hypotension 2/2 vasodilation
- agitation, lethargy, stupor, coma, seizure, anticholinergic sxs (flushing, dryness, mydriasis)
How is TCA ingestion managed?
What medications should be avoided in treating a TCA ingestion?
ABCs, supportive care, activated charcoal early
- NaHCO3 for widened qrs
- seizure=benzo
- hypertonic saline can overcome sodium channel blockade
- Tx hypotension with epi or NE, avoid using dopamine as it can paradoxically drive BP lower
- Avoid treating anticholinergic effects with physostigmine
What are the antidotes to these common poisonings?
- Iron
- neuroleptics–>dystonic reactions
- anticholinergics
- Isoniazid
- Warfarin
- Iron=Deferoxamine
- Neuroleptics (dystonic rxn)=Benztropine
- Anticholinergics=Physostigmine
- Isoniazid=Pyridoxine (Vitamin B6)
- Warfarin=Vitamin K
How should barbiturate and benzo intoxications be managed?
- There is no direct antidote
- Give activated charcoal by mouth or a tube through the nose into the stomach
- Breathing support, including oxygen, intubation if necessary-these patients may have severe respiratory depression
- IV fluids
- Treat symptomatically
What are the toxic effects of the following plants?
- Oleander
- Jimsonweed
- Dumbcane
- Oleander- effects similar to cardiac glycosides and digoxin toxicity.
- Jimsonweed- anticholinergic effects-lethargy, agitation, flushing, dryness, paralytic ileus, mydriasis
- Dumbcane- causes local (not systemic) toxicity due to the insoluble calcium oxalate crystals. Ingestion can cause severe oral pain due to mucosal irritation.
- What are symptoms of digitalis poisoning?
- What electrolyte abnormalities are common?
- How should this be treated?
- asymptomatic for several hours then develop significant gastrointestinal symptoms-anorexia, nausea, vomiting, and abdominal pain; Neurologic sxs-confusion and weakness; any arrhythmia but most likely bradyarrhythmias and heart block
- Hyper and hypokalemia are common abnormalities encountered
- Patients who recently ingested digoxin may benefit from activated charcoal. Consult toxicology to determine if digoxin-specific antibody (Fab) fragments are warranted
- What are symptoms of serotonin syndrome?
- What are drug classes that can cause this?
- What are general management principles?
- What is the antidote?
- Signs and symptoms associated with serotonin syndrome include confusion, agitation, disorientation, tremor, vomiting, shivers, myoclonus, ataxia, hyperreflexia, mydriasis, and hyperthermia.
- amphetamines, MAO inhibitors, SSRIs, SNRIs, tryptans, fentanyl, lithium-many more, look at a table!!!
- Discontinue of all serotonergic agents; Supportive care aimed at normalization of vital signs; Sedation with benzodiazepines, Administration of serotonin antagonists (cyproheptadine), Assessment of the need to resume use of causative serotonergic agents after resolution of symptoms
- Antidote if the above fails is cyproheptadine!!!
- What are symptoms of organophosphate poisoning?
- What is the antidote to this?
- DUMBBELS: diarrhea, urinary incontinence, miosis, bradycardia, bronchospasm, emesis, lacrimation, and salivation. Also associated with muscle weakness, paralysis, and CNS effects.
- The antidotes are atropine and pralidoxime.
- Describe symptoms consistent with methemoglobinemia
- What types of drugs can cause this?
- What is the treatment?
- dizziness and cyanosis following ingestion of medication known to cause methemoglobinemia
- Many drugs including local anesthetics, sulfonamide antibiotics, phenazopyridine, dapsone, and chloroquine can cause methemoglobinemia.
- Methemoglobinemia usually responds to methylene blue.
What are common cardiac manifestations of TCA overdose?
-hypotension. Sinus tachycardia with QRS prolongation, atrioventricular block, ventricular tachycardia, ventricular fibrillation, torsades de pointes (less common).
- What are symptoms associated with arsenic poisoning?
- What are mees lines?
- If exposed to arsenic gas, the most common presenting symptoms are abdominal pain, hematuria, and jaundice along with diminished mental status.
- Mees lines are white lines on the fingernails indicating chronic arsenic poisoning
- What are symptoms associated with hydrogen sulfide exposure?
- What clue can be helpful to alert you to this exposure?
- rotten egg smell, keratoconjuctivitis, and upper airway irritation with coughing and confusion.
- Coins and jewelry will blacken
- What are the most common ingested agents leading to hospitalization in children?
- What are the effects of clonidine exposure?
- How should clonidine exposure be managed in the ED?
- Clonidine and buprenorphine are the most common agents causing hospitalization due poisoning in children.
- Clonidine is an α2-agonist that causes low blood pressure, bradycardia, and sedation.
- Early management of the poisoned child should include assessment and treatment of problems with airway, breathing, and circulation, as well as early consultation with the poison control center and/or a toxicologist. Activated charcoal can be effective early in the ingestion. If required intubate prior to activated charcoal. Narcan can be used to reverse respiratory and neuro depression in clonidine ingestion
What history points need to be taken, if possible, for any ingestion?
- Time of ingestion
- Maximal possible dose of ingestion
- Formulation of ingestion
- Co-ingestions
- Patient’s medical conditions
- What is the dose of activated charcoal?
- When is activated charcoal of highest benefit?
- Activated Charcoal (0.5 – 1 g/kg)
- Within an hour of ingestion
-What is the dosing of calcium gluconate?
10% Calcium Gluconate 60 mg/kg (0.6 mL/kg)
