Certified Neuroscience Registered Nurse (CNRN) Practice Exam

Which of the following must be monitored when administering Ondansetron for PONV?

1. Blood glucose levels

2. QT interval

3. Electrolyte levels

4. Kidney function

The correct answer is: QT interval

Monitoring the QT interval is critical when administering Ondansetron, particularly because this medication can lead to QT prolongation, which increases the risk of potentially life-threatening arrhythmias such as Torsades de Pointes. The QT interval reflects the time taken for the heart's electrical system to reset after each heartbeat. Prolongation of this interval can indicate an increased risk of cardiac complications, especially in patients with pre-existing heart conditions or those taking other medications that may also prolong the QT interval. While other aspects such as blood glucose levels, electrolyte levels, and kidney function are important to monitor in a clinical setting, they are not specifically associated with the administration of Ondansetron for postoperative nausea and vomiting (PONV). Thus, QT interval monitoring stands out as a necessary precaution when using this medication.