Medical emergencies Flashcards
What is a HCIG test used for?
To see if someone is pregnant
What is an MSU test?
Mid stream urine sample
What are normal lactate levels?
0.5-1 mmol/L
During a paracetamol overdose, when should paracetamol and salicylate levels be taken?
How much paracetamol must the person have taken for these levels to be measured?
Take bloods within 4-8 hours of a single ACUTE (not staggered) paracetamol
Wait until 4 hours
They must have ingested >75mg/kg
What is the threshold for treatment for a paracetamol overdose?
100 mg/L at 4 hours
What are the two treatment options for a paracetamol overdose?
Activated charcoal
Acetylcysteine (Parvolex) injection 200 mg/mL
When would a paracetamol overdose be classed as staggered?
If it has been taken over the course of more than one hour
When would you give activated charcoal in paracetamol overdose?
Consider if the dose is more than 150mg/kg AND patient presents within 1 hour of ingestion.
What is the treatment regimen for acetylcytseine?
150mg/kg over 1-hour in 200mL dextrose 5% (or sodium chloride 0.9%)
then
50mg/kg over 4-hours in 500mL dextrose (or sodium chloride 0.9%)
then
100mg/kg over 16-hours in 1000mL dextrose (or sodium chloride 0.9%)
What is extremely common in acetylcysteine treatment (occurs in 20% of patients)?
Anaphylactoid reaction
NOT IgE mediated
What is extremely uncommon in acetylcysteine treatment and how do you treat it?
What do you do if the patient has previously had this?
- Anaphylactic reaction
- Chlorphenamine 10mg IV, once symptoms have settled then start with next infusion bag.
- If severe symptoms then consider Rantidine 50mg IV.
- For adults with previous anaphylactoid reactions or repeated anaphylactoid reactions these should be given before the acetylcysteine infusion.
How would you treat a Phenylephedrine overdose?
Activated charcoal if within 1 hour of ingestion
Diazepam - if agitated
How would you treat a guaifenesin overdose?
No specific treatment due to low toxicity
How would you treat amitriptyline overdose and what mg/kg would be considered to be a serious overdose?
What might the patient experience with this overdose?
Highly toxic by ingestion
15 mg/kg - serious
Treatment:
- Activated charcoal to eliminate
- Sodium bicarbonate and IV magnesium (to counteract cardiac arrythmias and metabolic acidosis)
Convulsions, hypotension, agitation, cardiac arrythmias
What would you need to test in an amitryptilline overdose?
Use a cardiac monitor and ECG due to QRS and QT prolongation risk
Describe the mechanism of action of acetylcysteine in paracetamol overdose
- Paracetamol has a toxic metabolite = NAPQI (n-acetyl-p-benzo-quinone imine)
- Usually conjugated with glutathione, which is synthesised from cysteine (rate limiting factor), glutamate and glycine (found in abundance in the liver)
- In overdose, hepatic glutathione stores are used up
- NAPQI builds up causing hepatotoxicity and cell death
- Cysteine is not well absorbed after oral administration. However, acetylcysteine is well absorbed and rapidly enters cells. It is a pro drug that converts to cysteine, providing the rate-limiting step for glutathione synthesis
What 3 amino acids are needed for glutathione production?
Which one is the rate limiting step?
Cysteine- rate limiting
Glutamate
Glycine
What is the max dose in IV paracetamol in mg/kg and what do you need to consider?
15 mg/kg (up to 1g QDS)
So max of 60 mg/kg in 24 hours
Important in lighter patients
<67 kg- dose is less than 4g a day
What is the ABCDE of assessing a patient in a medical emergency?
Airways and oxygenation
Breathing and ventilation
Circulation and shock management
Disability due to neurological deterioration
Exposure and examination