Perhaps most impressive was the dashboard that was developed and sent to clinicians every month or so, which identified how often the test was used, observations regarding its use, and whether anything important was being missed.
Dr. Gherasim notes that when Michigan first began taking a serious look at the biomarkers, most minds were focused on COVID-19 testing. “Timing has interesting influences on the priority that a specific project gets,” she says. Initiating a new TBI test could have become lost in the pandemic’s shadows. “But we’ve met regularly, weekly, to talk about the progress from the incipience of this.” Interestingly, their experience with COVID rendered some unexpected help.
Like so many institutions, Michigan became familiar with using dashboards to provide updates during that time. “Anecdotally, the emergency medicine team started building dashboards in response to the COVID pandemic,” Dr. Gherasim says, and this approach has since been carried over into the TBI testing setting, with data elements that include turnaround time, number of providers using the test, CT use, and negative/positive tests. “That dashboard has been very helpful to disseminate a better understanding of how a new test worked.”
Dr. Korley sees real value in this type of feedback. “Once people see that others are using the test, they become more emboldened to use it themselves,” he says. Likewise, the audit and feedback has helped reassure clinicians who might be afraid that using the markers—and not ordering the routine CT scan—will lead to their missing an important injury. “They know that someone is paying attention, and that if something is missed we’ll know about it,” he says. “That has been a good security blanket.”
The laboratory has worked closely with the clinical team, and with Epic and its laboratory information system, which has been key to coordinating specific ordering test sets, with clear indications and clinical decision support for choosing patients to be tested and helping with results interpretation, Dr. Gherasim says. That has helped keep the orders focused. “It’s definitely been a team effort.”
Though Michigan is three years deep into the project, this is just phase one of the rollout, says Dr. Korley. While clearly useful in making decisions about CT orders, the markers could also prove helpful in risk stratifying patients, he says, since, in theory, they could do a better job than CTs of quantifying the extent of brain damage. But again, more data are needed to ascertain the right cutoffs for that indication.
Along with more data, physicians will need to acquire a deeper understanding of the markers themselves. There are, says Dr. Korley, many gaps that need to be filled.
In the aforementioned cases involving patients with coagulopathies, for example, a few clues have emerged.
The markers are not looking for damage to blood vessels per se, Dr. Korley explains; rather, they’re looking for damage to astrocytes (GFAP) and neurons (UCH-L1). If enough damage occurs to those, it’s likely there’s damage to the adjacent blood vessels. Patients on blood thinners may not need much blunt force to the head to cause some bleeding. “So they may have bleeding without damaging a ton of glial cells or neurons,” he says. “We think the amount of force required to cause bleeding in these patients is much less than that required for those not on blood thinners.”
Another key area will be to identify those age-specific cutoffs, as well as to understand the modest elevations that appear to occur naturally in older patients.
Says Dr. Gherasim: “Some institutions are considering different cutoffs for patients above 65. As we and other laboratories use the biomarkers, it would be interesting to see how the initial cutoff values or the FDA-approved values might evolve.”