13.16 CN IX and X: Glossopharyngeal and Vagus Nerve
- To test taste related to CN IX, use the same steps as in step 3 in the previous section related to CN VII, except introduce the substance to the posterior third of the tongue. This test is only done when there are specific concerns.
- To test gag reflex as related to CN IX and CN X, use a tongue depressor to tap near the lateral side of the pharynx near the tonsillar pillars or at the lateral posterior side of the soft palate. While doing this, use a penlight to illuminate the inside of the mouth and pharynx. Test on both sides of the mouth. See Video 14.
- Normally the client will gag, meaning that the pharynx will constrict/contract and the uvula and midline of the soft palate will move upward.
- Abnormal findings include an absent or decreased gag reflex, as well as an overactive gag reflex.
- Next, ask the client to open their mouth. Inspect the soft palate and uvula, and then have the client stick out their tongue and say “ahh.”
- Normally the soft palate is symmetrical and uvula is midline. When they say “ahh,” the soft palate should elevate and the uvula should elevate while remaining midline.
- Abnormal findings include an asymmetrical palate, a deviating uvula, and a palate that does not move upward.
- You may ask the client to swallow, or to take a sip of water and swallow, to ensure they have no difficulty swallowing.
- Throughout this assessment, continually listen to the client’s speech to ensure there is no hoarseness or difficult speaking.
- Note the findings.
- Normal findings might be documented as: “Gag reflex present, soft palate and uvula symmetrical and mobile with no dysphagia, dysphasia, or hoarseness.”
- Abnormal findings might be documented as: “Gag reflex absent. Client unable to clearly form words.”
Gag reflex video (from kaltura)
Video 14: Gag reflex
