A nurse is performing a cardiac assessment on a client and auscultates an S3 sound. The nurse should recognize that this sound represents which of the following heart conditions?

Hypokalemia is a low serum potassium level, usually below 3.5 mEq/L. It can be caused by diuretics that increase potassium excretion, such as thiazides or loop diuretics. Potassium is essential for normal muscle and nerve function, and hypokalemia can impair cardiac, skeletal, and smooth muscle activity. Symptoms of hypokalemia include fatigue, weakness, muscle cramps, arrhythmias, constipation, and hyporeflexia.

1. Dyspnea is difficulty or labored breathing that can be caused by various respiratory or cardiac conditions, such as asthma, pneumonia, pulmonary edema, or heart failure. It is not a specific sign of hypokalemia, although severe hypokalemia can affect respiratory muscle function and cause respiratory failure.
2. Oliguria is a reduced urine output, usually less than 400 mL per day or 30 mL per hour. It can be caused by various renal or fluid balance disorders, such as acute kidney injury, dehydration, or shock. It is not a specific sign of hypokalemia, although severe hypokalemia can impair renal function and cause renal failure.
3. Pitting edema is a swelling of the tissues that leaves an indentation when pressed with a finger. It can be caused by various fluid retention disorders, such as heart failure, liver cirrhosis, or nephrotic syndrome. It is not a specific sign of hypokalemia, although severe hypokalemia can affect fluid and electrolyte balance and cause edema.

The nurse should place a towel under the client's head to protect it from injury during the seizure. The nurse should also loosen any tight clothing, remove any objects that could harm the client, and maintain a patent airway.

Place the client in a prone position is wrong because it can compromise the client's breathing and increase the risk of aspiration. The nurse should place the client in a side-lying position after the seizure to facilitate drainage of oral secretions and prevent aspiration.

Holding the client's arms and legs still is wrong because it can cause injury to the client or the nurse. The nurse should not restrain or interfere with the client's movements during the seizure but rather ensure a safe environment and observe the seizure activity.

Leaving the client to get help is wrong because it can endanger the client's safety and well-being. The nurse should stay with the client during the seizure and call for assistance if needed, but not leave the client alone or unattended.