Overdose and poisoning Flashcards
toxidrome
constellation of signs/symptoms that suggest a particular class of poison
Cholinergic Toxidrome
SLUDGE and the killer B’s
Salivation Lacrimation Urination Defication Gastro upset Emesis Bradycardia, Bronchorrhea, Bronchospasm
Also mioisis and lethargy
Organophosphates, carbamates, mushrooms
anti-cholinergic toxidrome
hyperthermia dry mouth urinary retention confusion mydriasis flushed skin tachycardia
Serotonin syndrome symptoms
Confusion, flushing, diaphoresis, tremor, myoclonic jerks, hyperthermia, hypertonicity, rhabdomyolysis
sympathomimetic toxidrome
hypertension mydriasis grinding teeth seizures tachycardia rhabdomyolysis
opiate overdose toxidrome (3)
miosis
reduced consciousness
bradypnoea
Causes of raised anion gap metabolic acidosis (mudpiles cat)
methanol uraemia DKA paraldehyde iron lactic acidosis ethylene glycol salicylate carbon monoxide aminoglycosides theophylline
Causes of normal anion gap metabolic acidosis (hands ups)
hyperventilation acids renal tubular acidosis diarrhoea ureterosigmoidoscopy pancreatic fistulas saline
3 broad principles of poisoning management
reducing absorption
increasing elimination
antidote administration
ways to reduce poison absorption (4)
kin decontamination
activated charcoal
gastric lavage
whole bowel irrigation
ways to increase poison elimination
haemodialysis
haemoperfusion
urinary alkalisation
When is activated charcoal most effective?
when given within 2 hours of ingestion and substance ingested known to be absorbed by charcoal
known carbamazepine or phenytoin ingestion - what can be done?
Multiple doses of charcaol
when is it acceptable to try multiple doses of charcoal?
known carbamazepine or phenytoin ingestion
Paracetamol toxic level?
more than 75mg/kg
Antidote for paracetamol overdose
N-acetylcysteine (NAC)
antidote for opiate overdose
Naloxone
How cyanide poisoning occurs
furniture containing nitriles burning in fires, release cyanide gas
does cyanide have an antidote?
yes several options e.g. methylene blue but people can survive with aggressive supportive care alone
What is ethylene glycol?
a substance commonly found in detergents, antifreeze and house hold cleaners, lethal
Treating ethylene glycol poisoning
ethanol, blocking alcohol dehydrogenase
Antidote to digoxin toxicity
Digoxin immune Fab (Digibind)
Digoxin immune fab or digoxin-specific antibody is an antidote for overdose of digoxin. It is made from immunoglobulin fragments from sheep that have already been immunized with a digoxin derivative, digoxindicarboxymethoxylamine. Its brand names include Digibind and DigiFab
Symptoms of digoxin toxicity
hyperkalaemia
arrhythmias
nausea and vomiting
green/yellow tinge to vision
The classic digoxin toxic dysrhythmia combines:
Supraventricular tachycardia (due to increased automaticity) Slow ventricular response (due to decreased AV conduction)
