Faster times, improved outcomes reported in observational study
Full execution of a three-part plan made a big dent in the time it took from PSC arrival to CSC groin puncture (111 versus 151 minutes for partial execution, P<0.001). The difference was driven by slashing time from PSC door-in to door-out (64 versus 104 minutes, P<0.001), Ryan McTaggart, MD, of Brown University's Warren Alpert School of Medicine in Providence, R.I., and colleagues reported online in JAMA Neurology.
In addition, at 90 days, patients in the full-protocol group were twice as likely to have a favorable outcome as those with partial execution of the protocol (50% versus 25%, P=0.04). Central features of that protocol were:
- Notify the CSC on arrival if patient scores 4 or higher on the Los Angeles Motor Scale (LAMS)
- Within 30 minutes of arrival, image the vessel at the PSC using CT angiography and noncontrast CT of the brain
- Share images with the CSC on a cloud-based platform
"Ultimately, though, we do not believe that the PSC emergent large-vessel occlusion protocol is the optimal workflow for patients with suspected large-vessel occlusion who can be transported directly to a CSC. Currently, however, the prehospital phase of the stroke chain of survival in the United States is far from optimal, and until such time, we must have PSC mechanisms in place by which patients with emergent large-vessel occlusion are identified and thus can achieve the best possible outcome. In addition, some patients will present to a PSC that is more geographically remote from a CSC, and, as such, having an efficient inhospital process will benefit those patients."
McTaggart and colleagues retrospectively reviewed the records of 101 consecutive patients transferred from regional PSCs to the CSC from 2015 to 2016. The 14 participating PSCs -- located between 6.4 and 73.6 km (4.0 to 45.7 mi) away -- started off unfamiliar with the management of patients with emergent large-vessel occlusion strokes before training in the protocol.
Ultimately, only 70 patients met the inclusion criteria for the study (22 of them in the full-protocol arm). Ground transport was used in all cases.
"There is still room for improvement in this process," the authors commented. "Early notification of the CSC within 30 minutes of PSC arrival happened for only 44% of patients, with only 10 notifications (14%) occurring within 15 minutes (our new target)."
They noted that their results may not be applicable to all geographical areas, and that some confounders -- such as those behind why some got partial versus full protocol execution -- remain unmeasured.
Furthermore, "given the low prevalence of patients with stroke likely to benefit from mechanical thrombectomy, a screening test (such as the LAMS score used in this study) is unlikely to achieve a positive predictive value much greater than 50%," Kori Sauser Zachrison, MD, MSc, and Lee H. Schwamm, MD, both of Boston's Massachusetts General Hospital, wrote in an accompanying editorial.
Zachrison and Schwamm suggested that many false positives will come out of the McTaggart protocol.
"The authors cite the maxim 'waste gas not brain' to justify such an approach. And this principle is likely justifiable," according to the editorialists, though they also argued for the importance of considering its costs.
"We are not provided with any data on the number of activations based on a LAMS score of 4 or higher that did not ultimately require transport to the CSC or mechanical thrombectomy. What were the costs to the system associated with the protocol implementation? How many critical care transport teams were deployed unnecessarily? How often was another stroke -- or even another time-critical condition -- adversely affected by the unavailability of the CSC critical care transport team because of a false-positive deployment?"
- Reviewed by Henry A. Solomon, MD, FACP, FACC Clinical Associate Professor, Weill Cornell Medical College and Dorothy Caputo, MA, BSN, RN, Nurse Planner
JAMA NeurologySource Reference: McTaggart RA, et al "Association of a primary stroke center protocol for suspected stroke by large-vessel occlusion with efficiency of care and patient outcomes" JAMA Neurol 2017; DOI: 10.1001/jamaneurol.2017.0477.
JAMA NeurologySource Reference: Zachrison KS, Schwamm LH "Implementation of rapid treatment and interfacility transport for patients with suspected stroke by large-vessel occlusion: in one door and out the other" JAMA Neurol 2017; DOI: 10.1001/jamaneurol.2017.0324.