Overdose

Question 1

You are the IMT1 working on the acute medical take. You have been asked to assess a 44 year old male patient who has been brought in by ambulance following a suspected overdose. Several empty packets of medications were found by the ambulance crew in his home, including paracetamol.

He has a background of depression but no other past medical history.

His initial observations on arrival in A&E are as follows:

Temperature 35.8, RR 10, Sats 95% on air, HR 80, BP 112/69

He appears drowsy on your initial assessment and smells of alcohol

How would you initially assess and manage this patient?

Answer 1

Preparation:
- Ensure personal safety and use appropriate PPE.
- Gather relevant collateral history from ambulance crew and family if possible.

A – Airway:
- Assess airway patency and check for obstruction.
- Reduced GCS may compromise the airway – perform airway maneuvers if needed (head tilt, jaw thrust).
- Prepare for possible intubation if airway protection is inadequate.

B – Breathing:
- Attach pulse oximetry.
- Start high-flow oxygen if hypoxic.
- Assess RR (10), effort, chest expansion, auscultate for abnormalities.
- Consider ABG and CXR for respiratory depression or aspiration risk.

C – Circulation:
- Check HR (80 bpm), BP (112/69), CRT
- 12-lead ECG
- Gain IV access (2 large bore cannulas) and send urgent bloods:
- FBC, U&Es, LFTs, CRP, Coagulation screen, Paracetamol & Salicylate levels, Ethanol level, VBG.
- Perform 12-lead ECG and attach continuous cardiac monitoring.
- If hypotensive, consider 500ml crystalloid bolus.

D – Disability:
- Assess GCS and pupil size/reaction.
- Check blood glucose.
- Look for signs of head trauma (alcohol-related injury).
- Consider naloxone if opioid overdose suspected.

E – Exposure & Examination:
- Check temperature (35.8°C – mild hypothermia).
- Examine for trauma, rashes, limb swelling, abdominal tenderness.
- Maintain patient dignity while fully examining.

Key Investigations & Management Priorities:
- Paracetamol overdose: Start activated charcoal if within 1 hour.
- If toxic paracetamol levels: Initiate IV N-acetylcysteine (NAC).
- Alcohol: Monitor for withdrawal and check ethanol level.
- Consider ICU referral if deteriorating consciousness or respiratory failure.

✅ Re-assess A-E frequently and escalate if condition worsens.

Question 2

What investigations would you like to perform?

Answer 2

This is a chance to mention anything you may have forgotten during your A-E assessment.

Bedside - I would like to perform a 12-lead ECG, particularly to assess for QTc and QRS duration. I would consider sending a urine toxicology screen if appropriate. An ECG may show other non-specific signs including ST changes and T wave flattening with U waves during the first 48 hours. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4944443/)

Bloods - I would like to send an FBC, U&Es, LFTs, CRP, Coagulation Screen, paracetamol levels, saIicylate levels, ethanol levels and I would take a VBG or ABG.

Imaging - Depending on the findings of my full history and A-E assessment this patient may require further imaging, for example with a CXR or CT head.

Question 3

What initial management would you like to initiate?

Answer 3

Initial management is supportive with protection and monitoring of the patient’s airway, breathing and circulation as required.

1. Activated Charcoal:
- If within 1-2 hours of ingestion and local guidelines permit.
- Effective for certain medications – consult ToxBase for guidance.

2. Specific Antidotes (if applicable):
- Paracetamol overdose: Check paracetamol level and consider IV NAC if toxic.
- Opioid overdose: Administer Naloxone if suspected.

3. Toxicology Guidance:
- Consult ToxBase or seek specialist toxicology advice for substance-specific care.

4. Escalation:
- Inform seniors early if patient deteriorates.
- Consider ICU/anaesthetic review if airway compromise, reduced GCS, or need for ventilatory support.

✅ Continuous Reassessment: Regular A-E reassessment and monitoring.

Question 4

Subsequent blood tests reveal a very high paracetamol level approximately 5 hours after the medications were taken.

How would you like to manage this patient?

Answer 4

1. Consult local / national guidelines regarding the Mx of paracetamol toxicity
2. Review paracetamol normogram to confirm if level above the treatment line
3. If so, treat with N-acetylcysteine as per HG and re-check bloods as PP
   * LFTs, INR, U&Es, paracetamol levels
4. Continue supportive measures and continuous A-E reassessment
5. Discuss with ITU colleagues so that they were aware of him in case of deterioration
6. Explain the plan to the patient and update any NoK if required
7. Involve mental health team if required both now and down the line for the possibility of future suicide prevention

Question 5

Please outline the primary mechanisms of the toxic effect of paracetamol and how this relates to the treatment options.

Answer 5

Small proportion of paracetamol metabolised by cytochrome p450 to form a toxic metabolite (NAPQI). NAPQI is conjugated by glutathione. In overdose, glutathione is depleted, allowing NAPQI to exert hepatotoxic effect. NAC acts as a glutathione donor. Must be administered within 8 hours of ingestion.

Question 6

You have one minute to please handover this patient to your registrar/consultant as if you were in the acute medical handover.

Answer 6

Situation: Mr X is a 44 year old male patient who presented with a mixed overdose including paracetamol.

Background: He has a background of depression and was found at home by paramedics with several packets of medication.

Assessment: I have performed an A-E assessment upon which he appeared to be haemodynamically stable and taken initial blood tests which have shown a significantly raised paracetamol level.

Recommendation: I believe this patient requires urgent treatment with a NAC infusion and further supportive measures as needed. I would be grateful for your senior input with regards to ongoing investigations and management.

Question 7

Over the next 48 hours, the patient’s U&Es, LFTs and coagulation profile remain grossly abnormal despite your treatment.

Are there any other management options to be considered?

Answer 7

1. Urgent referral: Contact local transplant center for advice and possible transfer.
2. Escalate care: Seek senior and specialist input (toxicology, gastroenterology).
3. Supportive measures: Ensure optimal management (e.g., fluids, electrolytes, coagulopathy correction).
4. Critical care: Consider ICU admission for close monitoring and advanced support.

‘Life in the Fast Lane’ has an excellent summary of managing paracetamol overdose:

https://litfl.com/paracetamol-toxicity/