Thanks to Dr. Joanna Middleton for leading the discussions this month
Edited by Dr David Lewis
Top tips from this month’s rounds:
Button Battery Ingestions
Acetaminophen Overdose / Poisoning – Delayed Presentation
Transient Ischemic Attack (TIA) – Follow-Up
Button Battery Ingestions
Take Home Points:
- Button battery ingestions are can potentially be very serious. Necrosis, perforation and erosion into vessels can occur in as little as 2 hours
- ALL nasal and esophageal button batteries should be removed within 2 hours of presentation to minimize mucosal damage
- Consider button battery ingestion in children presenting with dysphagia, refusal to eat and hematemesis
- Co-ingestion of a button battery with a magnet requires emergency removal regardless of where it is in the GI system
- Early GI consult is advised
The management algorithm form National Capital Poison Center covers all eventualities! (Click to enlarge)
Acetaminophen Overdose / Poisoning – Delayed Presentation
Take Home Points:
- N-acetylcystine (NAC) is a safe and effective antidote. Time to NAC is crucial to protect the liver from significant toxicity.
- Stated timing and dose are often unreliable and this needs to be taken into consideration.
- NAC is almost 100% effective if administered within 8hrs of ingestion.
- If time of ingestion is known for certain to be < 4hrs ago – draw blood for level at 4hrs post ingestion and use nomogram to determine who to treat.
- If time of ingestion is known for certain to be < 8hrs ago – draw blood for level immediately and use nomogram to determine who to treat (provide result can be obtained within 8 hrs – otherwise start NAC pending result)
- If time of ingestion is known for certain to be > 8hrs and < 24hrs – Commence NAC and draw blood for level immediately and use nomogram to determine whether to continue NAC.
- If time of ingestion is > 24hrs or unknown or ingestion is staggered – Commence NAC and draw blood for level immediately – Consult toxicology for advice – Only if level is undetectable and AST is normal then NAC can be discontinued, otherwise continue NAC and consult.
View the SJRHEM Acetaminophen Poisoning post here (includes Nomograms and NAC dosing):
New Acetaminophen Poisoning Guidelines from the Royal College of EM
See also this useful NEJM Review Article
For Children, this guideline is useful.
- Presenting between 4-24 hours (Time of ingestion is known)- use nomogram to determine who to treat.
- Presenting after 24 hours or time of ingestion unknown or ingestion spans > 24hrs
From: UpToDate
Transient Ischemic Attack (TIA) – Admit or Follow-Up
Take Home Points:
- All TIA patients need an ECG and baseline labs (CSBP recommended labs)
- Very High Risk TIA Patients (see below) should have a CT/CTA (or MRI/MRA) immediately
- High Risk TIA Patients (see below) should have a CT/CTA (or MRI/MRA) within 24hrs
- All TIAs should be followed up in a specialist TIA Clinic
- TIA’s + large artery stenosis – candidate for early revascularization (the sooner it is done the better the prognosis)
Full Canadian Stroke Best Practice Guideline can be viewed here
UpToDate: These results suggest that CEA is likely to be of greatest benefit if performed within two weeks of the last neurologic event in patients with ≥70 percent carotid stenosis. For patients with 50 to 69 percent stenosis, CEA may only have benefit if performed within two weeks of the last event.
