Which ECG finding is classically associated with hypothermia?

Which ECG finding is classically associated with hypothermia?

• A. Osborn waves
• B. Hyperkalemia
• C. ST-segment elevation
• D. Q waves

Answer: (A)

The main concept is that hypothermia alters ventricular repolarization in a characteristic way. As body temperature drops, the electrical recovery of the ventricles becomes uneven, creating a small, abrupt positive deflection at the end of the QRS complex—this is the Osborn wave (also called the J wave). These waves are most noticeable in the precordial leads and become more prominent as temperature falls, often seen when hypothermia is present. They tend to diminish or disappear with rewarming. This pattern is a classic teaching point for hypothermia on the ECG. Other common ECG patterns—such as tall, peaked T waves from hyperkalemia, ST-segment elevations from myocardial injury, or Q waves from prior infarction—are not specifically linked to hypothermia, so they don’t fit the classic hypothermia picture.

The main concept is that hypothermia alters ventricular repolarization in a characteristic way. As body temperature drops, the electrical recovery of the ventricles becomes uneven, creating a small, abrupt positive deflection at the end of the QRS complex—this is the Osborn wave (also called the J wave). These waves are most noticeable in the precordial leads and become more prominent as temperature falls, often seen when hypothermia is present. They tend to diminish or disappear with rewarming.

This pattern is a classic teaching point for hypothermia on the ECG. Other common ECG patterns—such as tall, peaked T waves from hyperkalemia, ST-segment elevations from myocardial injury, or Q waves from prior infarction—are not specifically linked to hypothermia, so they don’t fit the classic hypothermia picture.