Toxicology Flashcards
refers to very stable man-made compounds used as dielectrics and coolants, banned by Congress in 1979 after recognized to be persistent organic toxins that accumulate in body fat; reason large fish in Lake Hartwell carry warnings
PCB
widely used OTC analgesic that is safe at recommended doses but is a frequent cause of poisoning and can easily cause a fatal hepatocellular necrosis at higher levels; early symptoms (GI distress, nausea, irritability) may not occur until > 12 hrs after ingestion
acetaminophen
a black powdery substance processed in a manner that it has huge surface area for adsorption of chemicals, can be useful in the treatment of some poisons and also marks the stool during whole bowel irrigation; administration does require a risk-benefit analysis
activated charcoal
among symptoms of sympathomimetic toxidrome that is controlled with benzodiazepines
agitation
always the first thing to check in a new patient encounter
airway
a widely used and abused sedative having withdrawal symptoms of agitation, anxiety, hallucinations, confusion, seizure, mydriasis, tachycardia, hypertension, etc… benzodiazepines can help relieve these symptoms
alcohol
toxidrome in which the patient is blind as a bat, mad as a hatter, red as a beat, hot as a hare, dry as a bone, has bowel and bladder that have lost their tone and a heart that runs alone
anticholinergic
heavy metal with a garlic taste; toxic in several forms, each of which has some unique characteristics; diminishes ATP formation by a variety of mechanisms and definitely kills (e.g., used in intentional poisonings)
arsenic
mineral fibers used for many years because of their fire and chemical resistance and ubiquitous in older structures; use now is highly restricted; causes inflammation and scarring of the lungs and a rare cancer that affects the thin membrane lining the inner surface of the chest wall
asbestos
causes a very characteristic toxicity with initial tinnitus, nausea, vomiting and respiratory alkalosis due to direct stimulation of the respiratory center, but eventually gives way to high anion gap metabolic acidosis; give activated charcoal if < 1 hr post ingestion, maintain high urine flow, consider urine alkalization, hemodialysis may be necessary
aspirin
standard therapy for bradycardia due to poisoning; also combats bronchoconstriction and bronchorrhea, the other “killer B’s” of the cholinergic toxidrome
atropine
sedative-hypnotic drug class that kills readily (e.g., due in part to direct stimulation of GABA-A receptors); there is no antidote so must perform aggressive supportive care with airway protection as necessary… … benzodiazepines can help relieve withdrawal symptoms, switching to a long-half-life agent such as phenobarbital
barbiturates
e.g., atropine, are the classic causes of the anticholinergic toxidrome, but a variety of drugs in other classes also inhibit these receptors at higher doses including antihistamines and tricyclic antidepressants
belladonna alkaloids
class of drugs of abuse for which there are no proven drugs to use during withdrawal; instead months to years of time are required to wean person off in addition to emotional support
benzodiazepines
toxic levels of these drugs cause bradycardia (treated with atropine), hypotension (treated with IV fluids) and myocardial suppression for which glucagon is a textbook therapy but for which IV calcium and high-dose insulin and glucose are also effective
beta blockers
lab data that should be obtained immediately for this if the patient is comatose or mentally sluggish since “time is brain” if the value is too low
blood glucose
the B in a systematic approach to first aid of a poisoned patient
breathing
color of venous blood in cyanide poisoning since cells are unable to utilize oxygen
bright red
heavy metal used in some rechargeable batteries; mild exposure causes fever, chills and muscle aches while more significant exposure quickly damages lungs, kidneys and/or liver depending on route; has long half-life in body which cannot regulate its levels, has no specific antidote
cadmium
administered intravenously to offset a toxic degree of calcium channel blockade
calcium
older chelator used for the treatment of lead poisoning, clinician must use the right type as this is a different formulation of a common laboratory reagent; using the wrong formulation can cause a potentially fatal hypocalcemia
calcium disodium EDTA
an important component of therapy for people poisoned by drugs such as phencyclidine, LSD, mescaline, psilocybin, and “ecstasy”; may need to add benzodiazepine and additional treatment to counteract symptoms
calm reassurance
produced by the incomplete combustion of fuels, displaces oxygen from hemoglobin and turns it a cherry red color; resultant hypoxia causes disorientation, confusion, etc., nausea, muscle weakness, coma, death
carbon monoxide
destroy tissues within seconds, so do not induce emesis, do not attempt to neutralize, do not attempt lavage (risk of perforation)… instead, administer IV fluids and other supportive care, and attempt to correct tissue damage with surgery as necessary
caustic ingestions
abbr for cardiovascular drug class responsible for a disproportionate amount of deaths due to poisonings
CCB
toxidrome in which there is SLUDGE or DUMBBELLS, caused by organophosphate and carbamate insecticides, nerve gases, nicotine, physostigmine, bethanechol and similar agents
cholinergic
patients presenting with the sympathomimetic toxidrome due to this tend to be less agitated, paranoid, etc., than those with amphetamine poisoning
cocaine
referred to the combination of dextrose (glucose), thiamine and naloxone that used to be administered as standard treatment whenever a comatose patient was encountered
coma cocktail
important to measure and maintain using ice-baths, Bair Huggers, etc., as necessary
core temperature
has smell of bitter almonds, produced by burning plastic and nitroprusside metabolism, is used in electroplating, etc.; inhibits cytochrome oxidase
cyanide
agent that is administered to selectively chelate excess iron from the blood
deferoxamine
along with bowel sounds, provides the ability to distinguish the anticholinergic toxidrome from the sympathomimetic toxidrome
diaphoresis
standard therapy for treating seizures, but propofol is now also used
diazepam
Fab antibody fragments that are a specific antidote for digoxin toxicity
digibind
toxic levels cause anorexia, nausea, vomiting, bradycardia, AV block, ectopic beats, halos, among other disturbances due to blockade of Na+ /K+ ATPase
digoxin
aka BAL (for British anti-lewisite, remedy for lewisite, a toxic gas made from acetylene and arsenic and feared as a potential chemical weapon in WWII); chelator administered for treatment of lead, arsenic and mercury poisoning
dimercaprol
a frequent cause of the sedative-hypnotic toxidrome; also an antidote for methanol and ethylene glycol poisoning since able to displace these solvents from the enzymes that would rapidly convert them into toxic concentrations of toxic substances
ethanol
toxic colorless, odorless liquid with a sweet taste, a principal component of antifreeze and brake fluid; ingestion initially causes symptoms of drunkenness but its metabolism to oxalic acid causes precipitates that destroy the kidneys (reason FDA came into existence)
ethylene glycol
benzodiazepine receptor antagonist, current thinking is to not administer it in cases of benzodiazepine overdose because it can trigger seizures and supportive therapy without it is effective
flumazenil
a competitive inhibitor of alcohol dehydrogenase useful for treatment of methanol or ethylene glycol ingestion
fomepizol
principal antidote for most gas exposures, with other treatments added as needed
fresh air
medical terminology for “pumping the stomach”, not always beneficial
gastric lavage
administered intravenously to treat beta-blocker and calcium channel blocker poisoning; somehow increases cAMP levels in the heart
glucagon
toxidrome in which patients experience perceptual distortions, depersonalization, synthesthesia and present with vital signs that include hyperthermia, tachycardia and hypertension
hallucinogenic
a treatment option if the poison stays primarily distributed in body water and is not extensively protein bound
hemodialysis
aspiration of these is bad, either because their volatility displaces air being inhaled or because they are nonvolatile and create a barrier to gas exchange
hydrocarbons
gas noted for its “rotten eggs” smell
hydrogen sulfide
antidote for cyanide poisoning, it reacts with cyanide to produce a common form of vitamin B12
hydroxycobalamin
treatment that can decrease the half-life of carbon monoxide in the body from ~320 minutes to ~ 25 minutes
hyperbaric oxygen
when encountered in a poisoned patient, initially treated with a sedative such as benzodiazepines; may need to supplement with agents such as labetalol or nitroprusside
hypertension
generally, when to obtain IV access, pulse oximeter data, apply a cardiac monitor and provide high flow oxygen for a poisoned patient
immediately
administered in high doses along with glucose during calcium channel blocker or beta-blocker poisoning; clear proof of benefits, thought to be due to beneficial effects on cardiac metabolism
insulin
poisoning was typically seen in young children who ingested pregnant mom’s pills, symptoms begin with abdominal pain, vomiting and bloody diarrhea, and can spiral downward from there
iron
principal remedy rapidly administered in relatively large amounts to a poisoned patient presenting with hypotension
isotonic saline
blood glucose, CBC, BMP, ECG, blood gases, and serum levels of common poisons acetaminophen and aspirin are among the forms of this that should be obtained quickly for a poisoned patient
lab data
toxin commonly found in old paint, moonshine, improperly glazed pottery, batteries and as a component of solder; toxic effects thought to be due to its inhibition of sulfhydryl dependent enzymes and perhaps its competition with calcium in calcium-dependent cell processes
lead
a component of parenteral nutrition that can be utilized o create a lipophilic sink for drugs in the plasma in an attempt to keep them from reaching toxic levels elsewhere in the body
lipid emulsion
administered in 2 g boluses IV as treatment for torsades de pointes, giving additional boluses as necessary
magnesium sulfate
risperidone and quetiapine are among the newer agents that can cause this toxidrome in which there is hyperthermia, tachycardia, muscle rigidity, etc., symptoms that mandate aggressive supportive care and will typically resolve in 1-2 weeks if the offending agents are immediately discontinued
malignant neuroleptic
the simplest alcohol, used in canned fuels, paint removers, etc.; initial ingestion causes symptoms of drunkenness, but its conversion to formaldehyde and/or formic acid leads to permanent blindness (e.g., ~10 ml) or death (~>= 30 ml)
methanol
fish are the principal source of this organic heavy metal; it causes peripheral neuropathy, vision and hearing loss, mental retardation, etc.; its binding to sulfhydryl groups incapacitates key enzymes in the body
methylmercury
prototype for this class of analgesics that is the principal cause of drug-induced death (e.g., due to respiratory depression)
morphine
possibility to consider along with health care worker safety when encountering a poisoned patient
multiple casualties
antidote for acetaminophen poisoning, replenishes the glutathione stores so that acetaminophen metabolism proceeds without generating toxic intermediates
Nacetylcysteine
administered to reverse respiratory depression of opioid toxicity
naloxone
when to induce vomiting with syrup of ipecac
never
poorly soluble reddish-orange gas that is heavier than air, inhalation does little damage to mucosal surfaces and upper respiratory tract but it then dissolves in water in alveoli to form an acid that damages the endo- and epithelial structures… encountered in grain storage silos and welding operations
nitrogen dioxide
withdrawal syndrome characterized by agitation, anxiety, mydriasis, tachycardia, hypertension, abdominal cramping and diarrhea, salivation, yawning, and the skin appearance of having gone “cold turkey”; symptoms can be minimized by substituting agents with long half-lives and the slowly weaning off
opiate
toxidrome in which CNS depression and bradypnea are prominent; poisoned patient typically also has miosis, hypothermia, bradycardia, hypotension, hyperreflexia, decreased bowel sounds, scratch marks due to itchy skin, and needle marks
opioid
class of cholinesterase inhibitors used in insecticides (e.g., malathion) and as nerve gases in chemical weapons (e.g., sarin)
organophosphate
regulates permissible exposure levels for lead and can mandate paid time off when employees are exposed to higher levels that require time for elimination
OSHA
pungent pale blue gas that is a powerful oxidant and damages the tissue with which it comes in contact; is NOT approved as a safe and effective means of purifying room air
ozone
cholinesterase inhibitor used clinically that crosses the blood brain barrier and serves as an antidote for anticholinergic poisoning
physostigmine
antidote for organophosphate cholinesterase inhibitors provided the binding has not aged (i.e., become irreversible) but not for the carbamate cholinesterase inhibitors used as insecticides (e.g., aldicarb); has utility in the local ED as well as a battlefield hospital where nerve gases were deployed
pralidoxime
nomogram used to determine if plasma acetaminophen levels are sufficient to cause hepatic injury
Rumack-Matthew
toxidrome characterized by CNS depression, stupor, coma, hypothermia, bradycardia, hypotension, bradypnea like opioids, but has additional symptoms such as slurred speech, double vision and ataxia
sedative hypnotic
refers to the confusion, agitation, hyperthermia, hypertension, tachycardia, tremors, rigidity, etc., when drugs such as fluoxetine or venlafaxine are present at toxic levels, and obviously must be discontinued ASAP
serotonin syndrome
principal remedy when toxins cause a potentially deadly “membrane stabilizing effect” (= wide QRS complex) in the heart due to the blockade of fast Na+ channels; also can be administered to alkalize the urine to facilitate excretion of weak acid toxins; keep plasma pH < 7.55
sodium bicarbonate
aka DMSA, a chelator approved for use in children with lead poisoning, now also used in adults with lead poisoning and in the treatment of mercury and arsenic poisoning
succimer
colorless nonflammable gas with a strong odor (“just-struck match”) produced by fossil fuel combustion and used as a preservative for fruits and vegetables; forms acid on contact with mucous membranes and is highly irritating, need to flush exposed areas for 10-15 min to minimize damage
sulfur dioxide
toxidrome in which patient is often hyperalert, agitated, and paranoid with vital sign assessment revealing mydriasis, hyperthermia, tachycardia, hypertension, tachypnea, hyperpnea, diaphoresis and hyperreflexia
sympathomimetic
abbr. for class of drugs used by depressed people, overdosage causes a refractory hypotension that is the main cause of death and is seen in conjunction with other anticholinergic, antihistamine and alpha-antagonist toxicities; treatment is a challenge but utilizes symptomatic remedies described by other puzzle clues
TCA
routinely administered in ED to prevent Wernicke encephalopthy suspected of be alcoholic
thiamine
added to symptomatic therapy of hypotension when blood pressure remains low after administering isotonic saline (e.g., NE drip)
vasopressor
refers to the measurements of HR, BP, RR, body temperature and assessment of pupil size, muscle tone, bowel sounds, skin appearance, alertness, etc., that are crucial for proper treatment of a poisoned patient
vital signs
may be beneficial in poisoned patient, reason to use a product such as GoLYTELY
whole bowel irrigation
smell that indicates a sick child may have been overdosed with methyl salicylate
wintergreen
