Introduction: The failure to recognize an ischemic stroke in the emergency department (ED) is a missed opportunity for acute interventions and for prompt treatment with secondary prevention therapy. Our study examined the characteristics of misdiagnosed strokes in the ED of an academic teaching hospital and a large community hospital.
Methods: A retrospective chart review was performed from February 2013 to February 2014. A stroke was “missed” if practitioners in the ED did not initially consider stroke in the differential, or the diagnosis was delayed causing the patient to miss the therapeutic window for thrombolytic therapy.
Results: A total of 465 ischemic stroke patients were included; 280 patients from the academic hospital and 185 patients from the community hospital. One hundred three strokes were initially misdiagnosed. Fifty-five of these were missed at the academic hospital (22%) and 48 were at the community hospital (26%, p=0.11). Of the missed stroke patients, 26 at the academic hospital (47%) and 10 at the community hospital (21%) presented within 3 hours of symptom onset. At the academic hospital where a neurologist is consulted on all potential acute strokes, a neurologist was called for 95% of the accurate stroke diagnoses but only 36% of the stroke misses (p<0.001).
Factors independently associated with greater odds of a missed stroke diagnosis were nausea/vomiting (OR=4.02, 95% CI=1.60-10.1), dizziness (OR=1.99, 95% CI=1.03-3.84), and a positive stroke history (OR=2.40, 95% CI=1.30-4.42). Thirty-seven percent of posterior strokes were initially misdiagnosed compared with 16% of anterior strokes (p<0.001).
Conclusion: Greater than 20 percent of stroke patients admitted through the ED at both an academic center and community hospital had a missed diagnosis. These strokes were more likely to be posterior circulation strokes and associated with nausea, vomiting and dizziness. A neurologist consultation decreased the likelihood of a missed stroke. Next steps are the development of improved identification systems and tools in the ED to improve the accuracy of stroke diagnosis.