Ace the Certified Medical-Surgical RN Exam 2025 – Power Up Your Nursing Game!

In a patient with hyperkalemia, the characteristic ECG abnormalities include tall, tented T waves, a widened QRS complex, and a prolonged PR interval. These changes occur due to the effects of elevated potassium levels on cardiac myocytes.

Tall, tented T waves are often one of the earliest signs of hyperkalemia on an ECG. This alteration reflects changes in myocardial repolarization, where an increased extracellular potassium concentration affects the resting membrane potential of cardiac cells.

As hyperkalemia progresses, the QRS complex begins to widen. This indicates a delay in ventricular depolarization and is associated with a higher risk of severe arrhythmias. A widened QRS can sometimes morph into a sine wave pattern in advanced cases, which can be lethal.

Additionally, the PR interval may be prolonged due to impaired conduction through the atrioventricular (AV) node, which can also happen with increased potassium levels.

The other choices do not accurately represent the expected ECG findings in hyperkalemia. For instance, a flat ST segment and Q wave as mentioned in one of the options are not typical of this condition, and the absence of T wave, QRS, or PR interval changes does not occur in hyperkalemia; the presence of hyperkal