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Three Part Question

In [adults who present to the emergency department with acute ischemic stroke], what are the [rates and clinical characteristics] of [missed diagnosis]?

Clinical Scenario

A 62-year-old woman presents to the emergency department (ED) with difficulty walking due to five hours of constant vertigo. The dizziness is worse with head motion and better with her eyes closed. She has vomited twice but has no headache or other complaints. Her workup, including a CT scan, is negative. The patient remains ataxic despite meclizine and so she is admitted with diagnosis of peripheral vertigo. An MRI was done the following day shows a large cerebellar stroke. As the treating physician, you wonder how often the diagnosis of stroke is not recognized in the ED.

Search Strategy

Medline 1966-07/18 using PubMed, CINAHL, Cochrane Library (2018), and Embase
[(diagnostic errors [MAJR]) AND (exp emergency service, hospital [MeSH Terms]) AND (Cerebrovascular Disorders/diagnosis [MAJR]). Limit to English language.

Search Outcome

20 studies were identified; one systematic review addressed the clinical question. This meta-analysis analyzed 23 studies (15,721 patients). In addition, one recent population-based study was identified that was not included in the meta-analysis.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Madsen T, et al. 2016 USA	16 EDs in Ohio and Kentucky, 2,027 acute ischemic stroke cases	Retrospective cohort study	Portion of hospitalized patients with ischemic stroke not recognized in the ED.	14.0% of acute ischemic strokes were missed in the ED.	Observational study; could not account for ED physician perception, uncertainty of diagnosis or other competing diagnoses; errors in documentation could be contributing factor; included only admitted patients (not those discharged from ER); did not account for impact of neurology consult.
			Secondary outcomes included predictors of missed stroke diagnosis; characterize alternative diagnosis given to patients with missed strokes; and tPA eligibility among those with missed diagnosis	Younger age, decreased level of consciousness, nausea or vomiting, and posterior circulation strokes had high rates of missed diagnosis; the most common misdiagnosis given to patients was altered mental status; 1.1% (9% CI) of those with missed stroke were eligible for thrombolytic therapy.
Tarnutzer AA, et al. 2017 USA	23 studies including 15,721 patients with stroke symptoms	Systematic Review	Stroke diagnostic accuracy	Sensitivity 91.3% and specificity 92.7% for a stroke etiology; 9% of strokes are missed at initial ED presentation.	Some studies of modest quality, ED physician diagnostic uncertainty was variably handled in each study, impact of neurology consultation was variable in studies, studies did not address risk factors for misdiagnosis
			Characterize subgroups with more frequent rates of misdiagnosis	Misdiagnosis was more frequent among those with mild, non-specific or transient neurologic complaints such as dizziness.

Comment(s)

Failure to diagnosis stroke in the ED can preclude time-sensitive treatments and has been associated with poor outcomes. Approximately, 9-14% of patients having an acute stroke are missed in the emergency department setting. Not surprisingly, patients with non-specific presenting symptoms such as dizziness, nausea/vomiting, or altered level of consciousness have a higher rate of missed diagnosis. For this reason, posterior circulation strokes are more often missed. Small subsets of these patients (1%) are candidates for thrombolytic therapy. While diagnostic errors can never be eliminated, qualitative studies on the scope of missed diagnosis and factors leading to misdiagnosis are essential to improving rapid clinical recognition and diagnostic errors.

Clinical Bottom Line

Acute ischemic stroke is missed diagnosed in approximately 9-14% of ED patients, especially in patients presenting with non-specific complaints such as dizziness, nausea/vomiting, or altered level of consciousness.

References

1. Madsen TE, Khoury J , Cadena R, Adeoye O, Alwell KA, Moomaw CJ, McDonough E, Flaherty ML, Ferioli S, Woo D, Khatri P, Broderick JP, Kissela BM, Kleindorfer D Potentially Missed Diagnosis of Ischemic Stroke in the Emergency Department in the Greater Cincinnati/Northern Kentucky Stroke Study Acad Emerg Med 2016 Oct;23(10):1128-1135.
2. Tarnutzer AA, Lee S, Robinson KA, Wang Z, Edlow JA, Newman-Toker DE. Potentially Missed Diagnosis of Ischemic Stroke in the Emergency Department in the Greater Cincinnati/Northern Kentucky Stroke Study. Acad Emerg Med 2016;23(10):1128-1135.