Anchoring bias can affect emergency room diagnosis and treatment

Anchoring bias is a concept that psychologists use to explain the tendency of people to overly rely on information that is initially presented to them, called the anchor.

As a Houston, Texas medical malpractice attorney, I have seen anchoring bias lead to misdiagnosis time and time again in emergency rooms.

I recently read about a case that illustrates how dangerous anchoring bias can be.

A 26-year-old woman who weighed 359 pounds went to a hospital emergency room with a rapid heart rate, rapid breathing, and shortness of breath that she had experienced over the past five days. She was initially seen by a resident physician (a new doctor still in training) and a fully-trained attending physician. They found that she had high blood pressure and an abnormal EKG.

The doctors did no further testing and concluded that she had a viral syndrome, chronic fatigue syndrome, mild anemia, and dehydration. After giving her some intravenous fluids, they discharged her to home. The next day, the patient returned to the emergency room by ambulance. Her condition rapidly deteriorated despite aggressive treatment and she died two hours after arrival at the emergency room.

It was not until autopsy that they discovered that she had a life-threatening pulmonary embolism. In the lawsuit, the plaintiffs and their medical experts allege that she had symptoms consistent with pulmonary embolism when she first went to the hospital. In this instance, the standard of care required ordering a d-Dimer test, which would likely have been positive. That would have led to a chest CT angiogram, which would have likely shown the pulmonary embolism and have led to treatment that would have saved her life.

In this case, the anchoring bias came about because the emergency room providers looked at a young woman who is morbidly obese. With just a glance at the patient, they permanently dismissed the possibility that a woman so young could have a pulmonary embolism.  Instead, they settled on rather harmless diagnoses that could be explained by her obesity, without going through a full battery of tests to rule out dangerous conditions, including pulmonary embolism, aortic dissection, and myocardial infarction (heart attack).

I am working on two cases now where I also believe anchoring bias was a significant issue.

In one case, a 39-year-old man went to an emergency room (ER) three days in a row complaining of the worst headache of his life. During the first ER encounter, the emergency physician diagnosed him with migraine headache and hypertension and gave him medications to treat those conditions. The next day, he went to a hospital ER and receive the same diagnoses and treatments. The third day, same story. Shortly after discharge, he went home and had a massive stroke. The doctors and nurses allowed anchoring bias to get in the way of a thorough workup to explain the cause of his terrible headache, in three ways. First, the patient was young. Second, the patient was healthy. Third, the diagnoses seemed settled to them based on the prior two days’ emergency room visits.

In another case, a man in his 40s went to a hospital ER after having multiple projectile vomiting spells, dizziness, and the inability to walk independently. He told the ER providers that he had fallen and hit his chest four days earlier. He had a large bruise on his chest from that fall. Without doing a thorough workup to explain why the patient was having these symptoms, the emergency room doctor quickly diagnosed him with vertigo and discharged him.

The next day,  this man’s conditions took a dramatic turn for the worse. His wife saw him slumped over on the couch, unable to speak clearly, and unable to use one side of his body normally. She frantically called 911 and told them that her husband had been to the hospital the day before and diagnosed with vertigo, but she thought he was having a stroke. You can hear his terribly slurred speech on the 911 recording. The ambulance and emergency medical technicians (EMTs) arrived and took them to the same hospital, where they reported that he had vertigo. The patient and his wife had to wait for hours for treatment in the emergency room, despite his classic stroke symptoms.

I believe that the emergency room triage nurse and physicians allowed anchoring bias to affect their diagnosis and treatment in several ways. First, the patient was young. Second, they referenced the incorrect diagnosis on the first ER visit. Third, the EMT crew reported incomplete information to the triage nurse, only referencing vertigo. The hospital ER providers ran with their preconceived notions and caused a significant delay in this patient’s treatment.

This case shows the power of anchoring bias. The doctors and nurses anchored on the initial information available to them and ignored a significant piece of information—the fact that the patient had a hard fall four days earlier that caused a large bruise on his chest—that should have led to testing for a dissected (torn) artery. If they had done the testing, they would have discovered his dissected artery and would have likely been able to prevent him from having a stroke.

What you can do

If you find yourself back in the hospital or emergency room multiple times for the same condition, be aware of the risk that anchoring bias poses to your treatment. Be sure to explain your symptoms and story thoroughly to your providers on each encounter. If it seems like your doctor is talking like a broken record and not taking heed to the information you are sharing, then ask for a second opinion from a specialist. You may even wish to mention your concern about anchoring bias to the second opinion physician. That may help snap them out of the daze to focus their attention appropriately.

If you or someone you love has been seriously injured because of misdiagnosis or poor health care, our experienced medical negligence attorneys can help. Click here to send us a confidential email via our “Contact Us” form or call us at 281-580-8800.

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Robert Painter is a medical malpractice attorney at Painter Law Firm PLLC, in Houston, Texas. He is a former hospital administrator who represents patients and family members in medical negligence and wrongful death lawsuits against hospitals, physicians, surgeons, anesthesiologists, and other healthcare providers. In 2017, H Texas magazine named him one of Houston’s top lawyers. Also in 2017, the Better Business Bureau recognized Painter Law Firm PLLC with its Award of Distinction.

Robert Painter
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Robert Painter

Robert Painter is an award-winning medical malpractice attorney at Painter Law Firm Medical Malpractice Attorneys in Houston, Texas. He is a former hospital administrator who represents patients and family members in medical negligence and wrongful death lawsuits all over Texas. Contact him for a free consultation and strategy session by calling 281-580-8800 or emailing him right now.