Which diagnostic test would NOT be used for diagnosing epiglottitis?

The correct choice indicates that a CT scan is not typically used for diagnosing epiglottitis. In the context of epiglottitis, which is an acute inflammation of the epiglottis and can lead to airway obstruction, certain diagnostic tests are preferred due to their ability to quickly visualize critical anatomical structures in the neck.

Lateral neck X-rays are particularly valuable as they can reveal a classic finding known as the "thumbprint sign," which indicates swelling of the epiglottis. This imaging modality is non-invasive and can be performed rapidly, making it suitable for emergency situations.

Arterial blood gases (ABG) may be useful in assessing the patient’s respiratory status, especially if there is concern for airway compromise or hypoxemia, but it doesn't directly diagnose epiglottitis. Similarly, a complete blood count (CBC) can reveal an elevated white blood cell count, suggesting infection, but it also does not specifically confirm the diagnosis of epiglottitis.

In contrast, while a CT scan can provide detailed images of the soft tissues of the neck, it is generally not the first-line diagnostic tool for epiglottitis. The urgency of the condition often requires quick assessment and intervention, and the potential need for patient transportation and