Teaching emergency medical services (EMS) to use the finger-to-nose (FTN) test in patients with neurological symptoms can contribute to early detection of posterior circulation stokes, according to a poster presented at last week’s 2018 International Stroke Conference.
“We noticed a large proportion of EMS-missed stroke cases in a previous study were in the posterior circulation,” presenter John A. Oostema, MD, of Michigan State University College of Human Medicine and Spectrum Health in Grand Rapids told Elsevier’s PracticeUpdate.
“Strokes in this area may present with different symptoms than strokes in the anterior circulation. Perhaps as a result, patients with posterior stroke receive tissue plasminogen activator (tPA) less often and less rapidly than patients with anterior strokes.”
He pointed out that patients with posterior circulation strokes are less likely to present with unilateral weakness or difficulty speaking, the hallmark of an anterior circulation stroke. They are more likely instead to have vague symptoms, such as dizziness, imbalance, loss of coordination, or visual disturbances.
Dr. Oostema and colleagues identified all consecutive ischemic stroke cases that were transported by any of three EMS agencies in a single county in southwestern Michigan over a 21-month period. Each stroke was classified as being anterior, posterior, or indeterminate, based on the final hospital discharge diagnosis.
After a 12-month period collecting baseline data, all paramedics working in the county received a 30-minute online training module that targets recognition of stroke symptoms. In addition, paramedics from one of the three EMS agencies working in the region also received in-person training on performing the FNT test. The investigators then compared the rate at which EMS personnel were able to identify posterior strokes before and after the training intervention.
Overall, 777 ischemic stroke cases were transported by EMS during the 21-month study period. Of these, 139 (18%) were posterior circulation strokes. Before training was initiated, the EMS personnel from the agency that received the FTN training recognized 45.8% of posterior strokes. After the training, they recognized 74.1% (P = .049). In comparison, the EMS from the other two agencies recognized 32% of posterior strokes before the training and 39.5% afterward (P = .505). The difference in stroke recognition rates between those who did and did not receive the FTN training was significant, at P = .011.
“Our study demonstrates that a relatively simple diagnostic manoeuver may reduce the gap in posterior stroke recognition by EMS,” said Dr. Oostema. “In general, stroke patients recognized as stroke by EMS receive [emergency department] ED stroke evaluations and tPA more quickly. Thus, improving EMS recognition may improve ED stroke care as well.”