CASE STUDY: Hidden in Plain View

A Case of Delayed Diagnosis of Stroke

When it comes to stroke, you’ve got one chance to get it right. Your patient’s outcome depends on near-instant assimilation of countless components gathered from different sources, including the patient themselves and their family.

In the following case, modified for privacy protection, consider how each component affected the diagnostic process.

AN UNLIKELY CANDIDATE

Lisa Ingram’s 15-year-old son called 911 one morning when she dropped a jar of jam and slumped to the kitchen floor unconscious. She’d been making breakfast for him and her 6-year-old daughter when the dizzy spell overtook her. Lisa had no risk factors for a stroke.

The emergency-medicine resident was given a medical history of altered mental status and syncope. He wasn’t concerned about a stroke in an otherwise-healthy 37-year-old. Lisa could not answer questions but opened her eyes to her name, bit down on a tongue depressor when her gag reflex was tested, and moved her arms and legs. Her sister arrived and reported that Lisa had been upset over marital problems and an impending divorce.

QuoteThe resident ordered a non-contrast CT of the head, as well as a chest X-ray. He thought about the possibility of trauma, encephalopathy, intoxication/overdose or medication reaction. The workup found no evidence toward causation. He suspected that the trouble at home had caused acute psychiatric stress that had brought about the dizziness and fainting. The attending physician agreed, and Lisa was admitted to the hospital.

The radiologist reported to the attending physician that the head CT was normal, with symmetrical anatomy and no hemorrhages, gross lesions, fractures, infarcts or edema. The hospitalist agreed with a diagnosis of conversion disorder.

When Lisa developed right-sided weakness throughout the late afternoon, a neurologist ordered an urgent MRI that revealed areas of acute ischemic injury in the left-middle cerebral artery—a stroke. By then, Lisa was clearly past the time window for thrombolytics or endovascular clot retrieval. She was transferred to the ICU for close neurologic monitoring, and was discharged a week later with speech impairment and mild right-side weakness.

Now, nearly two years later, Lisa can do everything she did before her stroke, just not as well or as quickly. Her case was settled soon after trial began: on the face of it, the atypical presentation could have fooled anyone. However, Lisa believes that her legal team advocated for her more strongly than her medical team. Her attorney pointed out several stages in her care that, if recognized, might have led to a full recovery.

LOST OPPORTUNITIES

  • EMTs listed stroke as a possible diagnosis, which was downplayed by the nurse who presented the case to the emergency-medicine providers.
  • The emergency-medicine physician nonetheless could have put stroke on the differential, given the patient’s altered mental status and syncope. Had he done so, it would have led to more testing by the hospitalist. The radiologist, too, might have made a different interpretation or recommended further imaging.
  • The radiologist might have identified what the neurologist saw when he took another look at the head CT—a left hyperdense middle cerebral artery (MCA), which is an early sign of stroke.
  • The hospitalist might have conducted an independent assessment of the patient separate and apart from the emergency physician, and begun tPA as a result.

COULD HAVE, SHOULD HAVE, WOULD HAVE

  • Everyone involved in this case agrees that the stroke team should have been called in to rule out the biggest risk first.
  • The emergency physician wishes he had ordered a CT with contrast, a better choice when stroke is a possibility.
  • The emergency physician is still smarting from the allegation that he didn’t take the patient’s symptoms seriously because she is female. A simulated jury contended that he wouldn’t have so quickly made a diagnosis of conversion disorder, had the patient been male.
  • Rear-view reads are the bane of radiology, and even a neuro-radiologist acknowledged that the left hyperdense MCA would have been easy to overlook. Still, the miss was recognized when pointed out to members of the simulated jury.

Stroke quoteUPGRADE YOUR STROKE GAME

Of the nearly 800,000 new stroke diagnoses each year in the U.S., nearly 10% are misdiagnosed at first presentation.1 Not only is acute stroke being missed, but diagnosis of transient ischemic attack (TIA) is frequently overlooked. Patients who have had a TIA are at greatest risk of going on to have a more serious stroke, even if the symptoms disappear. Commit to brushing up on your stroke education, beginning with the basics:

  • Stroke comes in camouflage. The classic symptom of one-sided weakness that physicians associate with stroke can lead them to discount stroke in the absence of hemiparesis. The misdiagnosis rate can be as high as 35% when symptoms are ambiguous. To highlight the ambiguity, dizziness and vertigo are the symptoms most tightly linked to missed stroke. Whereas not many things cause weakness on one side of the body, the causes of dizziness or vertigo are numerous enough to warrant moving stroke to the top of your differential.2
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  • The three main stroke syndromes that present without lateralizing weakness are isolated symptoms of dizziness, headache, and difficulty speaking. Blurry vision, eye-movement abnormalities, and confusion may also present.
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  • Diagnostic imaging of stroke includes multi-modal techniques such as noninvasive angiography and perfusion imaging. In the early stages, both CT and MRI imaging can be inconclusive.3 Can you choose the appropriate imaging study to order for suspected intracranial hemorrhage and suspected ischemic stroke? Can you conduct the appropriate examination for suspected TIA?

DON’T BE THROWN BY DEMOGRAPHIC FACTORS

  • Not surprisingly, delayed diagnosis disproportionally affects those under age 50, women, and minorities.
  • Risks rise as patients age, but when young patients get strokes, they are more likely to have complications.

UPGRADE YOUR HANDOFF PROTOCOL

  • Handoff communication is especially critical when you have no prior relationship with the patient. Imagine how subsequent care might have improved in this case if the concern about stroke had been clearly communicated to the emergency-medicine team. Imagine how the radiologist would have viewed the case if suspicion of stroke had been relayed with the imaging order.
  • Simulation is an ideal way to raise competence and confidence in your hospital or clinic. No high-tech equipment is required to simulate communication among the providers involved in emergency care. Use a department meeting to advocate for cross-department simulation training.
  • With simulation, you can practice SBAR communication (Situation, Background info, Assessment, Recommendation) to get everyone on the same page.
  • The I-PASS system may be better suited to the time-critical ED setting, because it encourages shared reasoning that could expedite care. The steps involved are:
    • Illness severity
    • Patient summary
    • Action list
    • Situation awareness and contingency planning
    • Synthesis by the receiver
  • In several studies, handoff-related errors decreased after I-PASS implementation.4 Here, too, simulation drills can strengthen the team by giving them the opportunity to work through weak points in the system.
  • Regardless of the communication system, make sure it allows for each treating provider to ask questions.

DON’T BE THROWN BY ANOTHER PROVIDER’S INITIAL ASSESSMENT

  • High-functioning systems allow for independent judgment. A questioning attitude can benefit your patient when you’re reviewing prior assessments presented during handoffs.
  • Consider the hospitalist in this case who accepted the diagnosis of conversion disorder. The patient’s history of altered mental status and syncope could have triggered a request for further testing.

SHARPEN YOUR DIAGNOSTIC THINKING

Improving diagnosis is recognized by the National Academy of Medicine as a public-health priority. Diagnostic and communication skills can be bolstered through case-specific live or online courses, by reviewing root-cause analyses of adverse events, and by studying the cognitive process involved in optimal medical decision-making. Your immersion in medicine can provide you with constant practice.

While the pressure to get it right every time is unrelenting, the people and systems that support getting it right also support you, so take advantage of those resources. Even in those cases when your one chance to get it right ends up being wrong, your patients will be more likely to see you as their strongest advocate.

References
1 https://www.cdc.gov/stroke/facts.htm
2 Tehrani, A., Kattah, J., Kerber, K. et al. “Diagnosing Stroke in Acute Dizziness and Vertigo.” Stroke. 2018; 49:788–795.
3 Sanossian, N. “Utilization of Emergent Neuroimaging for Thrombolysis-eligible Stroke Patients.” June 14, 2016. Retrieved from https://doi.org/10.1111/jon.12369
4 Ransom, B. and Winters, K. “The I-PASS Mnemonic and the Occurrence of Handoff-related Errors in Adult Acute Care Hospitals: A Systematic Review Protocol.” JBI Database of Systematic Reviews and Implementation Reports. 2018; 16 1:20–26.