I have been pondering recently the increasing reliance on instrumental assessment (especially videofluoroscopic swallowing studies/modified barium swallows) in dysphagia evaluations. I get phone calls every so often from SLP’s in long-term care/skilled nursing facilities incensed that I did not do a VFSS on their patients. Never mind that I always have a reason
for not performing a video -- most commonly because either (a) the patient was not appropriate (remember, I work in acute care; I like to wait until the patient is reasonably stable to do a video, otherwise the patient may change so rapidly after the video is done that the results no longer reflect the patient’s current swallowing status. Unfortunately, by the time the patient is stable, he is often on his way out the door already!) or (b) results of the video would not change management (e.g., a 92-year-old with dementia who has occasional throat clearing with thin liquids and no history of pneumonia). To some of these SLP’s, the fact that a pharyngeal phase dysphagia was suspected or signs of aspiration were observed but a video was not done is automatic proof of incompetence, laziness, negligence, or all three -- an attitude which tends to drive me up the wall (go figure!).
What are the reasons behind the heavy reliance on VFSS or other instrumental assessments? They are numerous and interrelated. The ones I’ve come up with so far:
(1) Lack of training or experience in thorough clinical assessment;
(2) Characterization of clinical dysphagia assessment as “subjective” -- and therefore falliable and unreliable -- while instrumental assessment is “objective”;
(3) Viewing clinical dysphagia assessment as merely a “screening” procedure;
(4) Fear of litigation;
(5) Overemphasis on prevention of prandial aspiration (aspiration occurring during meals);
(6) Belief that “silent aspiration” is common and frequently harmful;
(7) Belief that VFSS reflects what happens during a meal; and
(8) Belief that only instrumental assessment can yield information about the physiology of the pharyngeal swallow.
I would like to talk about each of these in more detail, but for now let’s focus on the last one -- the belief that instrumental assessment is required to gain any reliable information about the physiology of a patient’s swallow.
This is a pervasive belief, espoused by some of the most influential people in the profession, as in the following pronouncement:
“…the physiology of the pharyngeal swallow is not observable at the bedside, and the reason for any aspiration cannot be defined.” Logemann, J. After the Clinical Bedside Swallowing Examination: What Next? American Journal of Speech-Language Pathology
1991; 1: 13-20.
One book (The Source for Dysphagia
by Nancy Swigert) gives the example that a dysphagic patient could have poor airway closure, causing aspiration during the swallow; poor tongue base movement and premature posterior spillage, causing aspiration before the swallow; or poor hyolaryngeal movement, causing pharyngeal residue and aspiration after the swallow, and asserts that it is impossible to tell which of these scenarios is occurring (and therefore plan appropriate treatment) without an instrumental assessment.
I don’t buy this. I’m not sure where we speech pathologists got the notion that the pharyngeal swallow is some mysterious process, revealing its secrets only to high-tech instrumental assessment (primarily VFSS/MBS). I can’t even remember the last time I saw something on VFSS that surprised me, based on the findings from my clinical evaluation. Are there times when instrumental assessment is important and necessary? Absolutely. Does it provide helpful information? Sure. Is it essential? I would say, not usually.
In the example above, I would argue that in most cases, we can
know which physiological abnormalities are occurring based on clinical examination alone. A patient with poor airway closure will exhibit abnormalities in voicing -- e.g., hoarseness, breathiness, difficulty changing pitch. Patients with poor oral control will show oral (especially lingual) weakness and/or discoordination. And hyolaryngeal movement can be judged by palpation. Combine these observations and the rest of the physical examination with knowledge of the patient’s medical history, the nature of the swallowing complaint, and observations of the patient with food and liquid trials, and an experienced SLP (or other swallowing specialist) is in a good position to determine clinically what is occurring pharyngeally.