Barriers and facilitators to ED physician use of the test and treatment for BPPV

Theme 1: ED physicians infrequently use the DHT or CRM because of prior negative experiences or difficulty remembering how to perform them

For more details on theme 1, see table 1.

Participants typically mentioned BPPV in their differential diagnosis of dizziness presentations, were aware of the DHT and CRM, and 90% had used these previously. However, the DHT and CRM were either infrequently used, even in cases of suspected BPPV, or not used at all by most participants, typically because of negative past experiences. Some participants said they stopped using them because it took too much time.

The typical negative experience was the DHT and CRM not being useful for determining the diagnosis or influencing the management or outcome of patients. Referring to DHT, one physician said, “So, I think I've probably tried several times and it didn't help, so I stopped doing it” (A15). Regarding use of the CRM, another participant said, “I think I haven't done it in a while because I had such a negative experience with it. I've seen the Epley maneuver and I've performed Epley maneuvers on non-sick patients…just practicing. There are YouTube, or I think the Annals, maybe the New England Journal, have a video on how to do the Epley maneuver. I think I'm doing it right. It's not successful in my case series. When I have a neurology attending do the exact same thing…thinking they are more expert at it, I still don't see patient improvement” (A13).

Some participants described experiences of the DHT or CRM worsening patient's symptoms. One participant stopped using the DHT after a memorable experience: “I did it on someone who complained about it to be perfectly honest. And they vomited after the maneuver. And I got a complaint, ‘Why don't [you] stop doing it.’ It affected my behavior. I was asked to stop doing it.” (A02) For some, the negative perception against the DHT/CRM was very strong. One participant recalled a colleague saying “The road to hell is paved with people doing the Dix-Hallpike maneuver” (A22).

Other participants did not use the DHT or CRM because of difficulty remembering the proper techniques. One participant described numerous efforts to learn and remember them: “In the last 20 years, I must have learned it a dozen times…it's one of those things like…I may learn it and if I don't use it, then a month will go by and I need it, and then “what the heck did I do?” And one of the neurologists that we have on staff…he does the Epley maneuver all the time, and he's constantly trying to show it. And I just can't seem to get it through my thick skull, how to do it and when to use it, and I'd like to” (B07).

Theme 2: ED physicians inappropriately rely on the history of present illness (HPI) or use the DHT but misattribute patterns of nystagmus

For more details on theme 2, see table 2.

Participants overwhelmingly relied on the HPI and particularly the type of dizziness (e.g., vertigo, lightheadedness) when considering causes of dizziness. One participant said, “The first thing I do is really try to nail down, is this vertigo, is this lightheadedness, or what do you mean when you say dizziness? Because I think that's my first branch” (A14). Participants generally focused on discriminating episodic symptoms vs constant symptoms, and positional triggers of symptoms when considering the possibility of BPPV.

Participants' overreliance on the HPI was particularly apparent when asked how they distinguish BPPV from vestibular neuritis. One participant said, “[For vestibular neuritis] I'm expecting some preceding viral prodrome or those sorts of things. If you don't have any other symptoms aside from the dizziness and if it's, you know, head movement causes my symptoms, then it definitely lends me to thinking it's BPPV” (A21). Some participants used simple heuristics: “I tend to call it BPPV if I think it is an isolated vertigo without accompanying symptoms” (A10). Even when prompted to describe examination elements that distinguish these entities, participants were generally either not able to describe any (e.g., “Not that I remember”) or reinforced their reliance on HPI: “So, there really isn't any physical finding beyond that with respect to the history” (B05). Other participants expressed apathy regarding identifying key components of BPPV or discriminating BPPV from vestibular neuritis and instead focused exclusively on identifying signs of a central lesion.

The HPI items were generally less relied on specifically for identifying central causes of dizziness and making decisions about the use of neuroimaging. Some participants did emphasize information about the onset characteristics (e.g., suddenness of onset, lack of positional components), other central symptoms, and the type of dizziness, with vertigo less likely to be central and disequilibrium or lightheadedness more likely to be central. However, the information most relied on to identify central disorders was older age (“If you're 80 and dizzy, you're getting a CT. If you're 30 and dizzy, you're almost never getting one” [B19]), general neurologic examination abnormalities (particularly coordination and gait abnormalities: “Can't walk, you can't go home” [A03]), presence of cardiovascular risk factors, lack of prior similar symptoms, and the lack of symptom improvement during the ED visit. Neuroimaging was considered a key part of identifying central disorders, though limitations to both CT and MRI were often expressed: “CAT scans aren't sensitive, MRIs take forever” (B15). A nystagmus assessment was infrequently mentioned as a key part of identifying central causes of dizziness. When used, participants said vertical or rotary nystagmus indicated a central disorder whereas horizontal or fatiguing nystagmus indicated a peripheral disorder. A few participants mentioned the head impulse test; however, these people reported difficulty with the test (“Its kind of hard to do that damn test” [B22]) or misconceptions interpreting it.

When participants did use the DHT to diagnose BPPV, their interpretation of the test was often based on whether it elicited dizziness symptoms without regard to nystagmus. Further, when nystagmus was included in the interpretation of the test, participants often considered only its presence or absence, without regard to its vector or other features (e.g., duration), or incorrectly specified the typical BPPV nystagmus characteristics. Some participants expressed difficulty in recognizing features of nystagmus. One participant said, “It's really hard to do. Which direction the fast component is, sometimes helps, although again it's very difficult in the ER to do. It's almost a yes there, not noted, nothing there at all. I don't have very good luck doing, you know, fast to slow nystagmus, one way or another” (A16). After being shown videotapes of hallmark patterns of nystagmus, participants nearly always incorrectly attributed patterns to disorders. Participants typically misattributed the hallmark nystagmus of vestibular neuritis to being BPPV and misattributed the hallmark nystagmus of BPPV to being a central lesion.

The one participant who demonstrated an expert level of ability in distinguishing BPPV and vestibular neuritis described experiences with colleagues this way: “Even my colleagues don't understand vertigo. They don't understand the simplest distinctions between benign positional vertigo and the other peripheral vertigos vs central. Our textbooks in emergency medicine tend to be wrong about certain particulars and the fault lies mostly in trying to lump benign positional vertigo discussions with the other peripheral vertigos.” This participant also expressed frustration in teaching others at the bedside, stating: “I just can't break through” (B22).

Theme 3: Positive prior experiences with the DHT/CRM facilitated DHT/CRM use

For more details on theme 3, see table 3.

Only a few participants reported occasional or routine use of the DHT/CRM in dizziness patients, all of whom described positive prior experiences. The positive experiences included using the DHT to successfully diagnose BPPV or seeing patients improve, often dramatically, after use of CRM. One participant said, “Certainly my most successful patient was my mother…I did the Epley maneuver and she got dramatically better” (A03). One participant exhibited an expert level of knowledge related to diagnosing and treating BPPV and reported using the DHT/CRM “all the time.” This participant emphasized how frequently the DHT helped distinguish among the various possible causes of dizziness, and specifically to identify BPPV based on the hallmark elicited pattern of nystagmus. He stated not needing to order other tests when the DHT was positive as another positive experience. However, among the other participants who described positive experiences, nearly all misattributed hallmark patterns of nystagmus. One participant who believed the DHT was helpful, but not the CRM, incorrectly reported that “horizontal nystagmus” indicated a positive DHT for BPPV (A02).

We explored several other factors that might influence DHT or CRM use. Social norms did not facilitate use because the few frequent users of the DHT or CRM reported that most of their colleagues were not users. There was very little awareness of published BPPV clinical guidelines or the CRM CPT billing code among users and nonusers. Prior training in residency or from continuing medical education did not seem to contribute to positive experiences or facilitate DHT/CRM use since many participants who described negative experiences also reported prior training. The participant exhibiting expert knowledge in BPPV learned about the DHT/CRM from a textbook on vestibular disorders, which he read because of being “fascinated by neurology” (B22).

Theme 4: Resources to facilitate use of the DHT/CRM should be brief, readily accessible, and easy to use, and include video examples

For more details on theme 4, see table 4.

Participants preferred clinical tools and resources that are brief, readily accessible, and easy to use. One participant said, “Just drill it down to something that's short and sweet and not a lot of fluff, and gets me the information I need in a short amount of time” (B07). Some participants said they would use educational resources outside of work hours to learn more about BPPV, but most said they would likely use them at the point of care. Some participants expressed an interest in more in-depth background material but most agreed that educational approaches should take less than 10 minutes to complete.

Participants preferred video-based resources and often sought these out. Many participants specifically mentioned searching YouTube for instructional videos, including for the DHT/CRM. Participants liked using videos for personal learning, and for teaching residents, colleagues, and even patients. Regarding nystagmus, participants preferred having multiple video examples so they could compare and contrast different patterns of nystagmus. Participants also said that videos should be well-narrated or annotated so that key features are clear. One participant, who misattributed the examples of nystagmus patterns, highlighted the value of video examples: “That was pretty dramatic ‘cause that's something I didn't know, and I didn't know I didn't know it. So it was all the better [way] to teach me” (B10). The one participant who demonstrated expert knowledge in BPPV and frustration teaching others said: “I think that [video examples of nystagmus patterns] can help especially with some good video images that describe what you're trying to get across” (B22).

In terms of platform, participants generally favored smartphone apps over websites because apps would be more readily accessible for regular use, especially because some websites may be restricted at work. Other factors often mentioned were the importance of endorsement by a trusted source including links to key studies that contributed to the evidence base.

When asked about the value of in-person training sessions, participants said CME sessions were memorable when the speaker was dynamic and used humor. In addition, participants expressed a preference for hands-on training experiences.