Question

The client is admitted to the emergency room with shortness of breath, anxiety, and tachycardia. His ECG reveals atrial fibrillation with a ventricular response rate of 130 beats per minute. The doctor orders quinidine sulfate. While he is receiving quinidine, the nurse should monitor his ECG for: A. Peaked \(\mathrm{P}\) wave B. Elevated ST segment C. Inverted T wave D. Prolonged QT interval

Short answer

Answer: The nurse should monitor for a prolonged QT interval on the patient's ECG after administering quinidine sulfate.

Step-by-step solution

Understanding atrial fibrillation

Atrial fibrillation is a condition where the heart's upper chambers (the atria) beat irregularly and chaotically, resulting in an ineffective pumping of blood. This leads to symptoms such as shortness of breath, anxiety, and tachycardia (a fast heartbeat). In the ECG, atrial fibrillation is characterized by an irregular ventricular response rate and the absence of distinct \(\mathrm{P}\) waves.

Understanding quinidine sulfate

Quinidine sulfate is an antiarrhythmic medication used to treat atrial fibrillation. It works by blocking certain electrical signals in the heart, which can help to restore a regular heart rhythm while also slowing down the heart rate.

Analyzing potential ECG changes after quinidine sulfate administration

Now, let's analyze each of the options given to see which ECG change is associated with quinidine sulfate administration: A. Peaked \(\mathrm{P}\) wave: This is not associated with quinidine sulfate as it mainly affects the atrial depolarization, which is usually not visible in atrial fibrillation. B. Elevated ST segment: This ECG change is associated with acute myocardial infarction (heart attack) and is not a result of quinidine sulfate administration. C. Inverted T wave: This ECG change could indicate ischemia or be related to various electrolyte imbalances and other conditions. It is not primarily associated with quinidine sulfate. D. Prolonged QT interval: Quinidine sulfate is known to prolong the QT interval, which is the time between the beginning of the QRS complex and the end of the T wave on the ECG. Prolonged QT interval is associated with an increased risk of certain types of ventricular tachycardia (rapid heart rate originating from the lower chambers of the heart).

Conclusion

After quinidine sulfate administration, the nurse should monitor the patient's ECG for option D, a prolonged QT interval, as it is the most relevant ECG change associated with quinidine sulfate.

Key concepts

Understanding Atrial Fibrillation

Atrial fibrillation (AFib) is the most common type of serious arrhythmia, or irregular heart rhythm. It originates in the heart's upper chambers, known as the atria, where electrical signals fire in a fast and disordered manner. This causes the atria to quiver, or fibrillate, rather than contracting effectively.

When a patient presents with symptoms like shortness of breath and anxiety accompanied by a rapid heart rate, these can be key indicators of AFib. During an ECG interpretation, a hallmark characteristic of AFib is the absence of distinct P waves and an irregularly irregular ventricular rhythm. This erratic rhythm can lead to poor blood flow and may increase the risk of stroke.

Management of AFib focuses on heart rate control, rhythm control, and prevention of stroke. Drugs like quinidine sulfate can be used to restore and maintain a normal heart rhythm and slow down the heart rate. Monitoring of the ECG is essential for assessing the effectiveness of the treatment and for detecting any potential side effects of the medication.

ECG Interpretation and Monitoring

Electrocardiogram (ECG) interpretation is a fundamental skill in recognizing and managing cardiovascular conditions. An ECG records the electrical activity of the heart and is depicted as a series of waves and complexes.

Here are few components commonly analyzed in an ECG:

• P wave: Reflects atrial depolarization
• QRS complex: Represents ventricular depolarization
• T wave: Indicates ventricular repolarization
• ST segment: Evaluated for elevation or depression, which may suggest myocardial infarction or ischemia
• QT interval: Duration of ventricular depolarization and repolarization

For patients undergoing treatment with medications like quinidine sulfate, continuous ECG monitoring is crucial to observe the response to the drug, as well as to watch for adverse effects such as QT interval prolongation.

Prolonged QT Interval and its Risks

The QT interval on an ECG represents the total time taken for the ventricles to depolarize and then repolarize. A prolonged QT interval is longer than the normal range and can be a side effect of certain medications, including quinidine sulfate.

A prolonged QT interval increases the risk of a potentially life-threatening condition called torsades de pointes, which is a type of ventricular tachycardia. This can lead to palpitations, fainting and even sudden cardiac death. Therefore, it's important for healthcare providers to monitor patients receiving quinidine sulfate for signs of QT interval prolongation.

By doing so, they can take appropriate action to avoid the progression to more serious complications. The goal is to ensure patient safety while treating the underlying condition like atrial fibrillation effectively.