Poison and Toxicity Flashcards
Is used to treat serotonin syndrome
Cyproheptadine
- discontinue the offending meds
- benzodiazepines (to manage agitation & muscle rigidity)
- severe cases, serotonin antagonists like cyproheptadine
Medication used in management of neuroleptic malignant syndrome (NMS) and Malignant hyperthermia (MH)
Dantrolene
- NMS can develop in pts taking antipsychotic agents (quetiapine)
- Malignant hyperthermia (MH) in susceptible pts s/t inhalation anesthetics (halothane) or succinylcholine
——————
NMS (fever, ams, muscle rigidity, and autonomic dysfunction such as tachycardia and diaphoresis). often after the administration of antipsychotics.
Malignant hyperthermia (fever, muscle rigidity, tachycardia, and metabolic acidosis)
Functional anemia due to reduced oxygen delivery to tissues. Occurs after exposure to oxidizing agents (eg, dapsone, nitrates, topical/local anesthetics).
Methemoglobinemia
(iron oxidized to Ferric iron Fe3+)
Binds to ferric iron in CYTOchrome oxidase a3 in the mitochondrial ETC. This blocks oxidative phosphorylation and results in anaerobic metabolism, causing lactic acidosis.
Cyanide
Cyanide poisoning s/t fires, mines, nitroprusside, grilling, plastics
Cyanide poisoning causes what to build up in the body
lactic acid
(lactic acidosis)
Markedly elevated lactate level (eg, >10 mEq/L) areexpected.
Cyanide toxicity can be treated with an antidote such as [1st line] or [2nd line], which directly binds cyanide molecules.
hydroxocobalamin (Vit B12 derivative)
sodium thiosulfate (2nd line)
Alternate tx is induction of methemoglobinemia w/ nitrites for alt bind
Sodium nitrite + sodium thiosulfate is an alternate treatment but is contraindicated in CO poisoning
Ingested Cyanide Treated with Activated:
charcoal
Acute cyanide toxicity causes neurologic and cardiorespiratory stimulation which presents with:
* Lactic Acidosis
* Cherry Red Skin
* ____,
* vertigo,
* ____,
* hyperventilation,
* tachycardia,
* nausea, and
* vomiting.
headache
dizziness
Neurologic, respiratory, and cardiovascular DEPRESSION s/t untreated cyanide poisoning eventually results in
- coma,
- seizures,
- ____,
- hypotension, and
- ___
bradycardia
cardiorespiratory arrest
Early symptoms of carbon monoxide poisoning are neurological and include
agitation, ___, ____
confusion
& somnolence
Faulty indoor heating, Gas motors or inhalation of smoke from fire/grill, etc.
can cause ___ poisoning
carbon monoxide
CO binds to Hgb with greater affinity than O2 (displaces oxygen) creating ______.
* Reduces O2 carrying capacity (Left shift curve)
* Decreases O2 unloading (less O2 delivery)
* Impairs O2 utilization (disrupts mitochondrial oxidative phosphorylation)**
carboxyhemoglobin
carbon monoxide poisoning
Sodium nitrite + sodium thiosulfate is an alternate treatment but is contraindicated in carbon monoxide poisoning
Work up indicated for diagnosis of Carbon Monoxide poisoning (3)
ABG: ↑ carboxyhemoglobin level
ECG ± cardiac enzymes
Acute carbon monoxide (CO) poisoning can induce a ____
which is associated with increased mortality.
myocardial infarction (MI)
severe CO poisoning can cause:
*Cerebral hypoxia: Drowsiness, confusion, seizures, syncope, coma
*Lactic acidosis: impairs O2 use
*Myocardial injury: Arrhythmias, MI, or pulmonary edema
High-voltage Electrical injuries:
_ c/b
* Acute compartment syndrome (intracompartmental muscle swelling)
* Rhabdomyolysis (leakage of heme pigment into blood)
* Heme pigment–induced AKI (intratubular cast formation)
Seizures
* rarely, Brain Herniation
Interruption of normal cardiac impulse conduction
* arrhythmias (Ventricular Fibrillation)
* Cardiac Arrest
Skeletal muscle necrosis
- Acute compartment syndrome (intracompartmental muscle swelling)
- Rhabdomyolysis (leakage of heme pigment into blood)
- Heme pigment–induced AKI (intratubular cast formation)
Treatment is
Aggressive IVF resuscitation
High risk of hyperkalemia from rhabdo → avoid potassium-containing IVFs (LR, NS, Plasma LYTE)
___ ± ___ & ___
→ indicated for Methanol & Ethylene Glycol ingestion
Fomepizole
Hemodialysis in severe cases (end-organ damage)
IV NaHCO3 if pH <7.3
BOTH
Methanol/Ethylene Glycol toxicity presents with
Altered Mental Status
Early: CNS sedation & inebriation, osmolar gap
Late: anion gap metabolic acidosis + tachypnea (compensatory)
* Methanol ingestion causes _.
* Ethylene Glycol (anti-freeze) causes _ & _.
- vision changes (cloudy eyes)
- Flank pain + Hematuria
* Urine oxalate crystals, hypocalcemia, AKI
Organophosphate poisoning presents with DUMBELS.
List the mnemonic
Muscarinic:
* Diarrhea/diaphoresis
* Urination
* Miosis
* Bronchospasms, bronchorrhea, bradycardia
* Emesis
* Lacrimation
* Salivation
Nicotinic:
* muscle weakness
* paralysis
* fasciculations
____ poisoning presents with Muscarinic (DUMBELS) ± Nicotinic sxs
Organophosphate
Management of organophosphate toxicity includes:
* Stabilization of ABCs.
* Decontamination (remove soiled clothes, irrigation of skin) to stop further exposure.
* Administer antidote: ____ (reverses muscarinic sxs & cholinergic hyperstimulation)
* After antidote give: ____ (reverses nicotinic & muscarinic symptoms)
Atropine (competitive inhibitor of muscarinic acetylcholine receptor)
Pralidoxime (cholinesterase-reactivating agent ↑ Ach breakdown)
Atropine does not act on the nicotinic receptors.
Neuromusc sxs → pralid
Pralidoxime ONLY given after Atropine, because transient acetylcholinesterase inhibitionmomentarily worsen symptoms
What is the antidote for anticholinergic toxicity?
Anticholinergic toxicity toxidrome:
* Agitation (mad hatter)
* Tachycardia (fast fiddle)
* dilated pupils (blind bat)
* dry skin/mucous membranes (dry bone)
* urinary retention (full flask)
* hyperthermia (hot hare)
* decreased bowel sounds
* HTN
Physostigmine
(an indirect-acting CHOLINERGIC AGONIST)
Hydrofluoric acid burns (eg, glass etching, cleaning solutions) are corrosive & can cause local tissue destruction with life-threatening ___ ( s/t Hypomagnesemia & Hypocalcemia).
It’s a medical emergency that requires rapid treatment with (3)
cardiac arrhythmias
Treatment:
*copious irrigation
*topical calcium gluconate gel
*cardiac & electrolyte monitoring