Flexible Endoscopic Evaluation of Swallowing (FEES)

While FEES can be facilitated with one practitioner, I HIGHLY recommend having two examiners to facilitate completion of the procedure; one person to scope the patient and to make verbal announcements describing the bolus presentation and sip/bite sizes for easier post-assessment review, and one person to assist with delivering the foods and liquids, recording sip/bite sizes, cleaning any spills, etc. (see below section). 

In my experience, the quality of a FEES is noticeably reduced when the endoscopist is trying to do everything (e.g., scope the patient and administer the bolus trials) without assistance. Therefore, just because we CAN complete a FEES independently, doesn't mean we SHOULD. For this reason, if you currently complete FEES independently without assistance, I highly recommend working to make making changes to have FEES become a two-person procedure.  

One very feasible way to work to make it a two-person procedure is to begin to take graduate interns if you do not already. I think many clinicians think taking graduate interns will slow you down and increase work load. However, with some planning, my experience is the exact opposite. They help to increase work flow efficiency and drastically help to reduce your individual workload. Typically, I now take interns for a minimum of 6-months/two consecutive semesters. In the first week of their internship, I train them how to: (1) setup a standard FEES tray; (2) quickly and accurately measure self-selected volume sips of water and bites of food; (3) deliver foods/drinks to the patient; (4) aide in troubleshooting of the FEES during the procedure; (5) clean up after the FEES; (6) show them how to use our standardized report template; and (7) begin to interpret FEES using scales such as VASES. By the second week, they start analyzing all bolus trials that are part of our standardized protocol (i.e., not additional swallows we test for therapeutic purposes). For me, this includes doing VASES ratings for the 9 boluses that are part of our standardized protocol and which are used to facilitate DIGEST-FEES grades. 

Weeks 2-4, we review FEES analysis together (after they did their first attempt) as a way to calibrate and increase our reliability and accuracy. During these weeks, they also complete the 'objective' section of our FEES report. This section included our standardized and non-standardized analysis outcomes. Depending on the interns development, they may also be writing up the history/chart review portion of the report. After that, we move to once monthly calibration meetings to continue to practice FEES interpretation as a group using our standardized metrics. On the backend, I do routine intermittent spot checking of their FEES analysis. By week 5, they begin to write up the full FEES reports  - understanding their interpretation will be very basic and standardized, and they I will add additional information to the more challenging sections of a report (i.e., the general impressions). However, this does require that you work hard to create a standardized yet comprehensive and thoughtful template for your FEES report that a graduate intern can use as an indepeth guide.

Once things are running smoothly with the intern, the typical workflow is as follows:

1. The intern setups for the FEES

2. The intern completes the patient interview (I have created a standardized history intake, which they use for the interview - I chime in at the end as needed)

3. I scope the patient (though, pending the intern, they may be scoping by the mid-/end- of their internship) while the intern assists in feeding, measuring self-selected volumes, and otherwise troubleshooting

4. The intern cleans up after the FEES is complete

5. The intern goes to their workstation and completes VASES ratings for all boluses within our standardized protocol, along with completing other FEES analysis 

6. The intern then uses our standardized report template to complete the report

7. The intern sends me the report to review, edit as needed, and submit.

   • Often times, I will review and edit the report with the intern then and there. It saves on time and they can hear me talk through my thoughts and it allows them time to ask questions. I may review some of the swallows as well to spotcheck their interpretation (I will do more of this at the beginning of their internship or with very challenging cases, and less of this after a month or so or with more mild/normal FEES)

   • I ask they do analysis and report writing on their own. Then, I a reserve time to address questions as specific portions of the day (e.g., the last hour of our work shift). This way, they aren't asking questions throughout the day and potentially slowing me down substantially.

Notably, I like to also take interns in pairs. This allows them the opportunity to work together and ask questions with each other before asking me. Lastly, by taking interns in pairs, because they tend to be slower with analysis and report writing, you can alternate which intern is going in to see which patient. For example, intern A may see patient 1 with you. Then, intern B can see patient 2 with you as intern A is analyzing patient 1. Then, intern A may see patient 3 with you as intern B is analyzing and writing up patient 2. So on and so forth. This should limit exactly how much time they need to work outside of work hours (though this will still be needed.

By having interns to assist with the FEES, I feel the quality of the exam is enhanced, workflow becomes more efficient, the exam is faster, and the exams in general are less stressful, cleaner, and much more precise/well controlled. This includes both the performance of the FEES and the interpretation the FEES. The interns, in return, are getting valuable exposure to FEES, and eventually, can start to gain experience doing the actual scoping. Furthermore, the graduate interns can assist with analysis of the FEES (e.g., doing VASES ratings), to further enhance standardization and increased quality. So it is a mutually beneficial relationship!

Below, is a video demonstration illustrate myself (James Curtis, PhD, SLP) passing a flexible laryngoscope transnasally on Allie Beam, MS, SLP, with assistance from Jina Nam, MS, SLP, completing what is known as a Flexible Endoscopic Evaluation of Swallowing ('FEES').  

Please note, the protocol used below was the outlined in the VASES normative study (Curtis et al., 2023) which involves 15 bolus presentations. However, clinically the standardized protocol I use is only 11 boluses, thus typically resulting in a shorter exam. For interested individuals, the protocol I use clinically is: 5 mL, held, cued, single swallow of green opaque water; 5 mL (not held or cued), single swallow of white coating water; 10 mL , single swallow of green opaque water; 20 mL , single swallow of white coating water; Self-selected volume of green opaque water (with sip size recorded using a digital food scale); Self-selected volume of white coating water (with sip size recorded using a digital food scale); 90 mL uninterrupted, sequential swallow of white coating water; 5 mL of blue dyed vanilla pudding (two trials); Self-selected volume of cracker (with sip size recorded using a digital food scale; two trials). All 11 of those trials are rated (by the intern, or myself) using VASES. DIGEST-FEES grades are then automatically derived using the VASES ratings from 9 of the 11 trials (all trials except the  5 mL cued swallow and the 90 mL sequential swallow).

The endoscopist performing the FEES may consider doing the following:

1. Describe the procedure to the patient prior to starting the exam. This should entail:

   • What the exam will entail (i.e., passing a scope through the nose to the back part of the mouth/throat)

   • What they will be asked to do during the exam (e.g., swallowing and non-swallowing tasks; avoid talking so we can look at swallowing and breathing)

   • What they will be asked to eat and drink (e.g., water that has been colored with food dye, vanilla pudding that has been dyed with blue food coloring, saltine cracker) 

   • How long the exam will take (e.g., 10-15 minutes)

   • Why we are doing the exam (e.g., to see if foods and liquids are 'sticking' or 'going down the wrong pipe')

   • Potential risks associated with the exam (e.g., 'It might feel a little weird or uncomfortable at first, especially when we first insert the camera. However, most people get used to it after ~30 seconds, with most people describing the exam to be a 1-2/10 in terms of pain/discomfort. Your mouth may be a little discolored, and you may have colored bowel movements for a day or two, because of the food dye we are adding to the water and pudding. Research also indicates that <1% of people may experience nose bleed, feeling faint or light headed, or having breathing difficulty.')

2. During the procedure, the endoscopist should:

   • Remind the patient of the swallow instruction prior to the start of self-administration.

   • Verbally announce the below for each swallowing trial. The verbal recording will be heard on the FEES playback and will substantially help with FEES ratings. Consider trying to verbally announce each of the below.

     1. 1. The swallow condition of each trial (e.g., "5 mL, green opaque water, single swallow", or "self-selected volume of white coating water, natural", etc.) prior to the start of self-administration.

        2. The start of each trial. Ideally, this is captured once the food or liquid touches the lips and first begins to enter the mouth. This helps a lot with VASES ratings for FEES by dictating the 'onset of the before the swallow phase.' I capture this by saying 'start time'.

        3. The number of swallows completed within the 'during the swallow' phase (as outlined by VASES).  Do this by looking at the FEES monitor and (peripherally) at the patient's throat. Verbally announce the number of swallows so the video recording can document this. This will help with post-FEES analysis (personally, I document number of swallows for each standardized trial in order to provide context for VASES residue and PAS ratings).

        4. Verbally announce the self-select volume sip size or bite size. This will have (ideally) been done with the aide of the second clinician.

   • Encourage the person to 'relax' or 'breath' after each 'single swallow' swallowing trial, to try to prevent the likelihood of additional swallows (which will, inevitably still occur - but at least it is prolonged). 

   • Then, cue patients to look up to the ceiling (this opens up the pharynx and larynx), say /i/ (this standardizes the housing space size for hypopharyngeal/piriform residue ratings and helps to visualize the laryngeal vestibule and vocal folds), breathe (this helps to visualize the subglottis, then look back down to a normal position. Notably, not all patients will be able to do this. But when able, it helps to improve post-exam FEES ratings.

   • If your equipment allows you to make real-time videoclips by stopping/starting the video recording, then I highly recommend stopping and immediately restarting the video immediately before the beginning of a new trial (right before the verbal announcement). This way, you are left with individual video clips, making looking for specific boluses much easier, than being left with one long video.

The second clinician involved in the FEES may be tasked with the following:

3. Before the procedure, as the endoscopic is describing the exam, this person may prepare the foods and liquids for the FEES assessment:

4. During the procedure, this person may do the following:

   • Stir the liquid boluses immediately prior to bolus delivery so that the colorants are well-mixed. If using white dye/barium, the contrast that facilitates the important coating effect can separate overtime. So it is important to mix it immediately prior to delivery.

   • Give the patient standardized bolus volumes for self-administration by the patient, or can feed the patient directly - depending on the needs of the patient.

   • Record self-selected volumes of normal size sips and bites:

     1. 1. For self-selected (non-standardized) volumes of liquid, the clinician can place the cup of water on a food scale, tare the scale so that it reads 0 mL. Then, give the cup of dyed liquid to the patient for a non-standardized sip ("take a normal size sip, whatever is normal for you"). Then, take the cup after the patient has taken a sip and place it back on the scale; record the scale output (e.g., -21.2 mL). Then tell the endoscopist what the sip size was so it can be recorded on the FEES video. 

        2. For self-selected (non-standardized) volumes of food, the clinician should change the unit on the food scale to grams. Then, the clinician can place the food item (e.g., cracker) on napkin on the food scale, tare the scale so that it reads 0 g. Then, give the food item to the patient for a non-standardized sip ("take a normal size bite, it can be part of it or all of it, whatever is normal for you"). Then,  after the patient has taken a bite, take whatever is left (if anything) and place it back on the scale; record the scale output (e.g., -1.5 g). Then tell the endoscopist what the sip size was so it can be recorded on the FEES video. 

   • Have napkins on hand to wipe the patients mouth as needed throughout the exam.

   • Have a cup of clear water on hand in case the endoscopist wants sips of clear water to clear internal residue.

   • Assist the patient as needed.

   • Be a second set of eyes for the endoscopist to ensure everything is running smoothly (are boluses in a standardized protocol/procedureal framework being skipped accidentally? is the equipment recording when it should be recording?, etc.).

The procedural framework for FEES should involve a pre-swallow assessment (anatomy, vocal fold mobility, secretions, etc.), a standardized swallowing protocol, and therapeutic interventions (testing of strategies and compensations; probing impairments further; etc.). As part of the standardized swallowing assessment, you may also include 'natural' trials to see what the patient is naturally doing. Though, be VERY cautious in your interpretation of this, as having a scope in your nose and swallowing in a clinical setting with people watching you is never natural. I would argue, that despite out best attempts to be natural, it is never observed, and so inferences during non-standardized 'natural' conditions should be taken with a grain of salt.

The ideal standardized swallowing protocol should using a standardized and self-selected volumes for the foods and liquids being tested. I highly recommend using a digital food scale (~$15-$20) to record the sip and bite sizes of self-selected volumes to provide context to of the pharygneal, laryngeal, and sublottic residue patterns. Recording sip/bite sizes also helps to better understand the effects of volume on swallowing outcomes.

I recommend instructing patients to complete any pre-measured standardized volume (e.g., 5 mL, 10 mL, 20 mL) in a single swallow as best as able, so that we are rating the volume swallowed, not the sip/bite size taken. If someone was given a 20 mL liquid trial, but did 3 swallows, we don't know if residue patterns observed are from a 20 mL swallow with two clearing swallows, or perhaps 10 mL and two 5 mL swallows, etc. Adding a 'single swallow' instruction will not prevent additional swallows, but it may allow for more time between the first and second swallow so that more confidence can be taken on what volume was just swallowed.

 The foods and liquids being tested during the standardized swallowing protocol should also include a range of consistencies (e.g., thin liquid, puree, regular solid), but may include additional material based on patient specific symptomology. For example, we have pineapple tidbit + pineapple juice on hand as needed for people who report symptoms with mixed consistency, but this isn't used as part of our standard protocol. 

Careful consideration should be given to the colorants used for the foods and liquids, as well as the type of instructions provided to the patient ('natural', 'single swallow', 'sequential', etc.). 

For more information on developing a standardized FEES protocol for your institution, as well as on standardized analysis of FEES, consider the following resources:

Curtis, J. A. (2022). A scoping review and tutorial for developing standardized and transparent protocols for flexible endoscopic evaluation of swallowing. Perspectives of the ASHA Special Interest Groups, 7(6), 1960-1971.

https://www.jamescurtisphd.me/tutorials/swallowing/colorants-for-feessees

https://www.jamescurtisphd.me/tutorials/swallowing/vases

Developing FEES Protocols

• Curtis, J. A. (2022). A scoping review and tutorial for developing standardized and transparent protocols for flexible endoscopic evaluation of swallowing. Perspectives of the ASHA Special Interest Groups, 7(6), 1960-1971.

• https://www.jamescurtisphd.me/tutorials/swallowing/colorants-for-feessees

Endoscopic Voice Assessment Measures 

• Poburka, B. J., Patel, R. R., & Bless, D. M. (2017). Voice-vibratory assessment with laryngeal imaging (VALI) form: Reliability of rating stroboscopy and high-speed videoendoscopy. Journal of Voice, 31(4), 513-e1.

• Patel, R. R., Awan, S. N., Barkmeier-Kraemer, J., Courey, M., Deliyski, D., Eadie, T., ... & Hillman, R. (2018). Recommended protocols for instrumental assessment of voice: American Speech-Language-Hearing Association expert panel to develop a protocol for instrumental assessment of vocal function. American journal of speech-language pathology, 27(3), 887-905.

New Zealand Secretion Scale

• Miles, A., Hunting, A., McFarlane, M., Caddy, D., & Scott, S. (2018). Predictive value of the New Zealand Secretion Scale (NZSS) for pneumonia. Dysphagia, 33, 115-122.

• Miles, A., & Hunting, A. (2019). Development, intra-and inter-rater reliability of the New Zealand Secretion Scale (NZSS). International Journal of Speech-Language Pathology, 21(4), 377-384.

Visual Analysis of Swallowing Efficiency and Safety (VASES)

• Curtis, J. A., Borders, J. C., Perry, S. E., Dakin, A. E., Seikaly, Z. N., & Troche, M. S. (2022). Visual Analysis of Swallowing Efficiency and Safety (VASES): A standardized approach to rating pharyngeal residue, penetration, and aspiration during FEES. Dysphagia, 1-19.

• Curtis, J. A., Borders, J. C., & Troche, M. S. (2022). Visual analysis of swallowing efficiency and safety (VASES): establishing criterion-referenced validity and concurrent validity. American Journal of Speech-Language Pathology, 31(2), 808-818.

• Curtis, J. A., Borders, J. C., Dakin, A. E., & Troche, M. S. (2023). Normative reference values for FEES and VASES: Preliminary data from 39 nondysphagic, community-dwelling adults. Journal of Speech, Language, and Hearing Research, 66(7), 2260-2277.

• Curtis, J. A., Tabor Gray, L., Arrese, L., Borders, J. C., & Starmer, H. (2024). Characterizing the Validity of Using VASES to Derive DIGEST-FEES Grades. Folia Phoniatrica et Logopaedica: Official Organ of the International Association of Logopedics and Phoniatrics (IALP).

• https://www.jamescurtisphd.me/tutorials/swallowing/vases