Wednesday, 9 March 2016

ECG of the Week - 7th March 2016 - Interpretation

The following ECG is from a 44 year old male with a history of non-complaint Type 1 diabetes. He has been found at home in a semi-conscious state.


Click to enlarge


Rate:

  • 42 bpm
Rhythm:
  • Irregular
  • Nil visible p waves
Axis:
  • Normal
Intervals:
  • QRS - Prolonged (200ms)
  • QT - 760ms (QTc Bazette 640 ms)
Segments:
  • ST Elevation lead aVR
  • ST Depression leads II, III, aVF, V2-6
Additional:
  • Deep T wave inversion leads II, III, aVF, V1, V3-5
  • Osbourne-J waves best seen infero-lateral leads
  • ST morphology in lead V1 has 'brugada' appearance
Interpretation:

Main differentials for these ECG features include
  • Hyperkalaemia - known T1DM altered conscious level could be associated with DKA
  • Metabolic disturbance - severe acidaemia
  • Hypothermia - slow AF, J waves
  • Drug toxicity - ? sodium channel blocker - 'Brugada' pattern in V1
What happened ?

The patient was found obtunded and further history suggested a drug ingestion including a tricyclic antidepressant and paracetamol. He was severely hypothermic, core temp 25oC, with a  significant metabolic disturbance:
  • pH 6.9
  • K 7.2 
  • HCO3 7 
  • U 10.6 
  • Creat 267
  • Lactate 26
For the patient's full set of clinical results see our lab case of the week here.

The patient was successfully resuscitated but unfortunately following his ICU admission he developed multi-organ failure and failed to respond to organ replacement and increasing vasopressor administration.

References / Further Reading
Life in the Fast Lane

Textbook
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.