Stroke: Managing Emergency Beds for Overall Financial Health
Each year, nearly 800,000 people in the United States suffer strokes, making cerebrovascular disease the nation’s third leading cause of death (behind heart disease and cancer). Virtually all of these patients end up in hospital emergency departments, where the ability to distinguish between ischemic strokes and the less common hemorrhagic strokes (which account for approximately 13% of cases) is crucial to determining the most effective course of treatment. Rapid triage and intervention are essential elements of a successful stroke program.
Erik Saluste
In 2007, the Stroke Center at Millard Fillmore Gates Circle Hospital (MFGCH), Buffalo, New York, transitioned from MRI to 64-detector CT for stroke triage, and in 2009, the center upgraded to a 320-detector scanner. The new protocol has enabled the program to take some patients from ambulance to scanner, saving critical time and freeing valuable emergency-department beds.
“At this point, we triage almost 100% of our stroke patients on our 320-slice scanner. We can acquire whole-brain perfusion images, which you cannot do on other systems. It’s really the way to go, in terms of both the time it takes and the results.” —Erik Saluste, imaging manager Millard Fillmore Gates Circle Hospital, Buffalo, New York
MFGCH implemented the 320-slice Aquilion ONE multidetector CT scanner from Toshiba America Medical Systems, Tustin, California, in June 2009, after using a 64-slice CT unit from the same vendor for stroke triage since 2007. “Without a dedicated MRI unit, it’s hard to get patients on there in an acute setting,” Michael Miller, MD, radiologist at MFGCH, explains. “There were issues, too, with screening patients who arrive confused and unable to give a history, which posed potential risks with putting them in an MRI environment. Regarding gadolinium toxicity and nephrogenic systemic fibrosis, that created problems getting rapid assessments of renal function, so for many reasons, we decided to emphasize the CT arm of the workup.” The state of New York requires that stroke patients receive a head scan without contrast within 20 minutes of reaching the emergency department and an initial interpretation of that scan within 40 minutes; Erik Saluste, imaging manager, says that MFGCH is now far exceeding that requirement, obtaining a head scan without contrast, a perfusion image with contrast, and a CT angiogram (CTA) of the head and neck within 45 minutes. “CTA doesn’t overestimate stenosis as much as MRI does,” Saluste notes. “You’re much better off with CT/CTA, and though we might still use MRI for additional imaging, it’s really up to the physician. There are some who still prefer MRI over CT, but that’s a very small population.” From Emergency Department to Hospital Bed According to Saluste, the Stroke Center at MFGCH sees 10 to 15 stroke patients a day, sometimes intercepting these patients directly from the ambulance before they even reach the emergency department. “I think the fact that we expedite things so well relieves the emergency department of patients who might otherwise be sitting there for hours,” Saluste says. “The stroke patients aren’t likely to spend a lot of time in the emergency department after they’ve been imaged. Many times, the patient is brought directly to intervention after CT. We’re providing much more timely care than we ever have—we get a quick scan and a very comprehensive study on their vessels and their brain tissue.” The Stroke Center has neurologists and neuroradiologists on-site 24/7; Miller says that the stroke team is currently responding to noncontrast head CT within 20 to 30 minutes of the patient’s arrival. “Nearly all acute neurologic presentations are triaged to our CT stroke protocol,” he says. “Then, we determine whether the next step is further imaging or appropriate medical therapy, which can consist of thrombolytics and/or heparin therapy, if appropriate.” Miller recalls attempting to handle the same patient load using MRI for triage; the results, he says, were far less efficient than those obtained using 320-slice CT. “Believe it or not, sometimes we have two or three workups going on at the same time,” he says. “Pushing those patients through one MRI suite wasn’t working well for us. The room time for MRI was 20 to 30 minutes; for the CT stroke protocol, it’s around 10.” He adds that CT—even top-of-the-line (and thus expensive) CT—is more cost effective than MRI because of the increased throughput that it allows. “To perform MRI effectively on all these people, we would need at least one more multimillion-dollar magnet installation,” he says. Further, Miller says that using CT for stroke triage has actually reduced medicolegal exposure by clarifying the best course for intervention while eliminating risk factors associated with MRI. “Risk management was more of an issue on the MRI side, in terms of the potential of injuring someone,” he says. “One problem was the contrast issue; others were implanted devices and metallic foreign bodies. The process for dealing with that takes up extra time, and time is brain.” Saluste adds that MFGCH is already ahead of the curve when it comes to CT dose reduction. “Utilization can go up dramatically as a result of bringing in new technology, whether it’s warranted or not,” he says. “We already know our dosing is well below the limit for the head, and that’s certainly an aspect of our patient care that we could potentially market to consumers. We’re extremely proactive when it comes to dose.” In the end, Saluste says, the use of 320-slice CT for triage helps the stroke team at MFGCH enforce a patient-centered approach. “This particular team is by far the best I’ve ever worked with,” he says. “While patient throughput is extremely important, even more important is intervening the correct way, the first time, for the best possible outcomes.” Cat Vasko is editor of Medical Imaging Review and