Overdose and poisoning Flashcards
What is the classic triad of symptoms for opiate overdose?
- Reduced consciousness
- Respiratory depression
- Miosis (pin-point pupils)
What key investigation must be performed if opiate overdose is suspected?
ABG –> assess the degree of type 2 respiratory depression
What is the antidote for opiate overdose?
Naloxone IV
What are the clinical features of bezodiazepine overdose?
- Agitation, euphoria
- Blurred vision
- Slurred speech
- Ataxia
- Slate-grey cyanosis
- Reduced consciousness
- Respiratory depression
- Hypotension, bradycardia
- Hypothermia
- Rhabdomyolysis
What is the antidote for benzodiazepine overdose?
Flumazenil
need to be careful as flumazenil can precipitate seizures
What are the clinical features of paracetamol overdose?
- N+V
- Hepatic necrosis (jaundice, RUQ pain, encephalopathy, hypoglycaemia)
- Renal failure, oliguria
- Metabolic acidosis
*usually asymptomatic until 24-72h later when acute liver failure occurs
What investigations should be performed if paracetamol overdose is suspected?
- Paracetamol (+ salicylate) level (only accurate 4h after ingestion)
- LFTs
- Glucose
- U&Es
- Prothrombin time
- ABG
How should paracetamol dose presenting <8h after ingestion be managed?
Activated charcoal if:
- > 12g or 150 mg/kg of paracetamol
- <2h (most effective <1h) after overdose
Acetylcysteine:
- only administer if you have plasma paracetamol level
- greatest effect if gent <12h after ingestion
How should paracetamol dose presenting >8h after ingestion be managed?
- Acetylcysteine if >12g or 150mg/kg, regardless of current plasma level
- 5% dextrose
How should paracetamol dose presenting >24h after ingestion be managed?
- Seek expert advice from Toxobase
What are the clinical features of mild salicylate toxicity?
- N+V
- Epigastric pain
- Tinnitus
- Dizziness
- Lethargy
What are the clinical features of moderate salicylate toxicity?
- Sweating
- Fever
- Dyspnoea
- Bounding pulse
What are the clinical features of severe salicylate toxicity?
- Confusion
- Convulsions
- Coma
What are the clinical features of life-threatening salicylate toxicity?
- Pulmonary oedema
- Metabolic acidosis
- Salicylate concentration >700 mg/L
What is the management of salicylate toxicity?
- Activated charcoal
- IV fluid resuscitation
- Potassium replacement
- Sodium bicarbonate
- Haemodialysis (severe cases)
What is the management of beta blocker toxicity?
Glucagon
Which TCAs are common to overdose on?
Amitriptyline
Dosulepin
What is the presentation of TCA overdose?
- Sedation
- Confusion/delirium
- Arrhythmia
- Seizure
- Hypotension
- Anticholinergic - hyperthermia, flushing, dilated pupils
- N+V
- Headache
What is the main investigation for TCA overdose?
ECG
- sinus tachycardia
- prolonged QRS
- unusual R wave
- prolonged QTc
What is the management of TCA overdose?
- Sodium bicarbonate
- Activated charcoal (1-2h since ingestion)
What is the management of sympathomimetic (cocaine, amphetamine) overdose?
Benzodiazepines
What is the management of carbon monoxide poisoning?
Hyperbaric oxygen
What is the antidote for bupivicaine?
Intralipid
What is the antidote for cyanide?
Hydroxycobalamin/Nitrites
