[EMed] Overdose Flashcards
what are the features of tricyclic antidepressant (TCA) overdose: anticholinergic?
- dry mouth
- blurred vision
- dilated pupils (mydriasis)
- hyperthermia
what are the features of tricyclic antidepressant (TCA) overdose: cardiac?
- sinus tachycardia
- arrhythmias
- vasodilation
what are the features of tricyclic antidepressant (TCA) overdose: CNS?
- reduced GCS
- seizures
- delirium
what is the mx for TCA overdose: Airway?
airway protection
GCS <8 = intubate
what is the mx for TCA overdose: Breathing?
high-flow O2
ABG analysis
what is the mx for TCA overdose: Circulation?
treat hypotension with fluid bolus +/- vasopressors
ECG
sodium bicarbonate 8.4% for arrhythmias and low BP
glucagon / MgSO4 for refractory anaemia
what does an ECG show for TCA overdose?
QRS prolongation >100ms
QTc prolongation >430ms
what is the mx for TCA overdose: Disability?
benzodiazepines for seizure control or agitation
avoid phenytoin
for TCA overdose, what do you do if pt is asx with no ECG or blood gas abnormalities >6 hours after ingestion?
discharge
what are the features of paracetamol overdose?
- nausea/vomiting, features of metabolic acidosis if levels ++
- abdominal pain/RUQ pain → overt hepatic failure with coagulopathy, deranged LFTs, hypoglycaemia, jaundice, acute renal failure
how do you manage paracetamol OD if ingestion <1 hour?
activated charcoal gastric lavage
what would you send off bloods for in paracetamol OD?
- paracetamol levels
- U+Es
- LFTs
- VBGs
- coags
how do you manage paracetamol OD if >8 hours from ingestion and >75mg/kg ingested?
start N-acetylcysteine (NAC)
how do you manage paracetamol OD if <8 hours from ingestion?
wait for paracetamol levels and treat as per normogram
when should a 4th bag of NAC be given?
if after full Rx: Cr above baseline, ALT 2x baseline or INR >1.3
what do you do if there are severe derangements in ALT/INR?
discuss with regional hepatology centre
what are features of opiate overdose?
- reduced conscious level
- reduced RR (<12 breaths/min)
- constricted pupils (miotic)
what is the mx for opiate OD?
A: airway protection, manoeuvres/adjuncts if needed
B: O2, may require bag-valve mask ventilation if apneoic or very low RR
what is the reversal agent for opiate OD?
naloxone
- initial dose 400mcg IV bolus
- bolus dosing can be uptitrated at 1-2 min intervals if no response
- aim: adequate ventilation
if pt responds to rx for opiate OD, what will they likely need and why?
ongoing infusion as T1/2 of opioids is»_space; naloxone (especially if ingested)
what is the antidote for: beta blocker?
glucagon
what is the antidote for: benzodiazepines?
flumazenil
what is the antidote for: cyanide?
dicobalt edetate / methylene blue
what is the antidote for: digoxin?
DigiFab / Digibind
