Case Study
Patient’s Migraine History Biases Diagnosis in ED

Description
A 41-year-old women presented to the ED with headache, she was treated and discharged within three hours with a diagnosis of migraine. Later the same day she had an acute event. A CT revealed a subarachnoid hemorrhage from a ruptured aneurysm.
Key Lessons
- Each provider owes it to the patient to make an independent assessment.
- Biases can narrow a clinician’s judgment and consideration of a patient’s complaints.
Clinical Sequence
A woman with a history of frequent visits to the Emergency Department (ED) arrived by ambulance with a complaint of headache, nausea, and vomiting.
The triage nurse documented that the reason for the visit was a headache, and that the patient was sleepy. A neurology exam was noted to be within normal limits, however, the record did not include a description of the exam.
The patient was diagnosed with a migraine. No further testing was ordered.
During discharge, the nurse documented that the patient was sleepy and would not walk and they were discharged with family. Two days later, the patient had an acute event. Imaging identified a ruptured aneurysm.
Allegation
The patient’s family brought a case against the ED team, alleging they breached the standard of care by discharging the patient without a complete evaluation.
Disposition
After review, the case was settled in the high range.
Analysis
Risk: The clinical team relied on a working diagnosis of migraine and did not obtain a detailed history, thus missing triggers that may have prompted further evaluation.
Recommendation: A number of factors can influence clinical reasoning including experience, knowledge, and biases. Failure to obtain a thorough history of a patient’s symptoms—or not performing a detailed physical examination—can limit consideration of other potential causes of presenting symptoms. Anchoring on a diagnosis of migraine provided diagnostic momentum; an adequate differential diagnosis was not established. Information that is not consistent with the working diagnosis should prompt reassessment. Develop strategies to reduce reliance on memory; step back and take a cognitive time-out to review information and diagnoses.
Risk: The patient’s family argued that her symptoms were not taken seriously and that a CT or further evaluation was not considered.
Recommendation: Clinicians need to protect against becoming immune to a particular patient’s complaints. Organizations trying to raise awareness regarding care of the chronic patient might consider use of diagnostic checklists to assist the care team in checking the completeness of their diagnostic process and expanding differential diagnoses.
Risk: The medical record contained value judgments rather than objective findings.
Recommendation: Documenting contemporaneously at the time of care is critical. A few words is often enough, but whatever is noted should be objective. Subjective comments can give the impression that staff is cynical and uncaring.
Additional Resources
- Massachusetts BoRM Advisory: Diagnostic Process in Inpatient and Emergency Department Settings
- Missed and Delayed Diagnoses in the Emergency Department: A Study of Closed Malpractice Claims From 4 Liability Insurers
- IOM Report: Improving Diagnosis in Health Care
- Canadian Family Physician: Patient safety and diagnostic error
This is a fictitious case that illustrates commonly encountered issues and is for educational purposes only. Any resemblance to real persons, living or dead, is purely coincidental.
See More MPL Cases
Medication Mix-up Contributes to Patient’s Death
Incidental Does Not Mean Insignificant
When Test Results Go Unspoken