An 85 year old female is bought to ED with right hip pain. She was found outside after unfortunately spending the night on the ground.
- ~48-55 bpm
- P:QRS = 1:1.
- PR ~ 240 msec
- QRS 120 msec
- QTc ~ 495 msec
- Incomplete ECG [V6 missing]
- Biphasic Inferior T-waves
- J-point notching [V2-5]
- Baseline wander and movement artefact
Interpretation – Sinus bradycardia (sinus arrhythmia) with first degree heart block and prolonged QTc. Presence of Osborne J-waves & movement (shivering) artefact suggestive of hypothermia. Biphasic T-waves (inferiorly) raise concern about ischaemia.
This patient had a fracture neck of femur. Her temperature was 28*C.
Whilst I have called this sinus rhythm with 1st-degree AV block, I have considered the diagnosis of 2nd-degree AV block (2:1).
- Morphology difference between P waves (blue circles) & those marked by red arrows.
- Red arrows appear to coincide with end of T-wave (blue dotted-line).
I look forward to the suggestions of our #FOAM ECG gurus….
There are no pathognomonic ECG changes in Hypothermia.
ECG Manifestations of Hypothermia.
- Sinus, junctional
- Varying AV blocks.
- Prolongation of PR & QT interval
- Osborne or J-wave.
- “Camel hump” sign.
- A positive deflection at the junction between QRS & ST-segment.
- Most prominent in precordial leads.
- Consistently present with body-temperatures < 25*C.
- Atrial fibrillation.
- Occurs in 50-60% of patients w/ temperatures < 29*C.
- Ventricular rate may be normal or slow.
- Shivering artefact.
- Ventricular fibrillation
- Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.
For more examples on these ECG changes take a look at “ECG changes in hypothermia” from LifeintheFastLane.com