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5 Most Commonly Misdiagnosed Conditions in the ICU

Missed diagnoses can lead to potentially fatal errors

The critically ill patients in an intensive care unit are the most closely monitored and tested patients in a hospital. Surrounded as they are by doctors, nurses and blinking banks of equipment, one might expect they would receive the very best medical care.

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Diagnostic errors in ICUs are more common than you may think.
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But not so, according to a recent study by patient safety experts at Johns Hopkins Medicine in Baltimore. Diagnostic errors are common in intensive care units (ICUs), according to study author Bradford Winters, an associate professor of anesthesiology and critical care medicine. He and his colleagues found that more than one-fourth of patients who died in an ICU had at least one missed diagnosis. The study estimates as many as 40,500 ICU adult patients a year die with an unknown medical condition.

Whether physicians' diagnoses were flat-out wrong or they failed to spot life-threatening illnesses, had doctors' diagnoses hit the mark, they would have started treatments that, in many cases, could have saved lives, Winters says. In addition to the deaths, such errors can lead to unnecessary surgeries, lengthy hospital stays and long-term disability in patients who might have otherwise fully recuperated.

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In an ICU it's easy to get pulled down the wrong diagnostic path, says Winters. Doctors receive about 7,000 pieces of information a day in this complex, distracting environment. "We're drinking from a fire hose" of information, he says.

Winters and other doctors from around the country gathered recently at a conference at Johns Hopkins aimed at improving patient safety by reducing diagnostic errors.

Diagnostic errors in the ICU are part of a larger problem, according to conference head David Newman-Toker, an associate professor of neurology and otolaryngology at Johns Hopkins. Overall, diagnostic errors result in the death of an estimated 40,000 to 80,000 hospital patients each year. 

Misdiagnoses also occur frequently in emergency rooms, where doctors are scrambling to decide whether patients should be admitted to the hospital or sent home. It's "the toughest place to practice medicine," he says, and, "as a consequence, we don't perform that well."

Just five conditions account for more than one-third of all missed diagnoses in the ICU. Read below for signs and symptoms of the conditions, the illnesses doctors often confuse them with and the tests physicians use to diagnose them accurately.

1. Heart attack

Death of — or damage to — part of the heart muscle, usually after a blood clot reduces or stops blood flow.

Symptoms: Classic symptoms include chest pain, shortness of breath, dizziness or light-headedness and breaking out in a cold sweat. Less common symptoms include nausea, vomiting, overwhelming fatigue and pain in the jaw, back, neck or shoulder blades. Women are more likely than men to have these less common symptoms, but men can experience them as well.

Confused with: Doctors may diagnose a heart attack as heartburn, a gallbladder infection or pulmonary embolism. In some cases, symptoms are mild enough that neither doctor nor patient realizes that the patient's symptoms are significant.

Diagnostic tests: Blood tests for heart muscle enzymes (cardiac specific troponin I or troponin T) can reveal whether the heart muscle has been damaged. Generally, the more damage to the heart, the greater the amount of troponin T in the blood. Although patients in the ICU are often connected to heart monitors, a special diagnostic electrocardiogram (EKG) is often required to detect a heart attack.

Treatment: Medications include aspirin and beta-blockers. Doctors also may perform an angioplasty procedure to open blocked arteries. Stents may be placed inside the artery to help keep it open.

2. Pulmonary embolism

A sudden blockage in a lung artery

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Symptoms: Patients usually have shortness of breath, chest pain and a cough.

Confused with: Symptoms can mimic those of an asthma attack, pneumonia, bronchitis or even a heart attack.

Diagnostic tests: If doctors suspect a pulmonary embolism, they can order a CT scan of the lungs. Nearly all patients with a pulmonary embolism have deep vein thrombosis, a formation of blood clots in the leg, thigh or pelvis. When patients have this condition, physicians should take precautions against the clot moving to the lungs.

Treatment: Clot-busting and blood-thinning medications are typically administered, as is supplemental oxygen if blood oxygen levels are low. In rare cases, surgery is required to remove the clot.

3. Pneumonia

Inflammation of the lungs because of infection

Symptoms: People usually experience coughing, fever and chills. They may also have difficulty breathing.

Confused with: The lung infection can also be confused with asthma or even tuberculosis. Also, because different forms of pneumonia require different treatments, mixing them up can waste precious time.

Diagnostic tests: A chest x-ray is typically used to confirm a pneumonia diagnosis. A CT scan also can detect pneumonia. Doctors can listen for a rattle in the lungs or do a pulse oximetry test to gauge how much oxygen is in the blood. A sputum test can reveal the cause of the infection and the severity of the illness.

Treatment: If the infection is bacterial, antibiotics generally will help clear it. If it's a viral pneumonia, antiviral medications are administered in some cases. Supplemental oxygen is given when blood oxygen levels are low.

4. Aspergillosis

An infection or allergic reaction caused by the aspergillus fungus, which commonly grows on dead leaves

Symptoms: Typical symptoms include coughing, fever, chills, chest pain, shortness of breath and headache. The fungus is common in the environment but generally only causes problems in people who have weakened immune systems.

Confused with: Aspergillosis can look like asthma, tuberculosis or acute respiratory distress (which can develop after a trauma or a drug overdose, among other causes). It also can mimic a bacterial or viral pneumonia.

Diagnostic tests: A chest x-ray or CT scan can show a fungal mass in the lungs. A sputum test can confirm that the aspergillus fungus is to blame. Skin and blood tests can reveal whether an allergic response is at the root of the illness.

Treatment: Antifungal medications and corticosteroids often are administered. If a fungal mass is causing bleeding in the lungs, doctors may opt for surgery to remove the mass.

5. Abdominal bleeding

Bleeding that starts in the stomach, esophagus, small bowel or colon

Symptoms: An unexplained drop in blood pressure and rise in heart rate can signal internal bleeding, as can weakness, light-headedness and shortness of breath. Symptoms can include vomiting and bloody or dark, tarry stools. Blood spilling into the lining of the abdominal cavity can cause pain, and the stomach will feel rigid.

Confused with: Internal bleeding is notoriously hard to diagnose in the ICU because many patients are already weak and light-headed, and blood pressure and heart rate fluctuations are symptoms of a number of conditions.

Diagnostic tests: Blood tests may show a low red blood cell count or anemia. A stool sample can also detect the bleeding. Endoscopy, angiography and CT and nuclear medicine scans can all help doctors pinpoint the source of the bleeding. If the patient already has a stomach tube in place, medical staff can take a sample of fluids in the stomach.

Treatment: Doctors may put a clip on a bleeding blood vessel or use heat, electric current or laser to stop the bleeding. Surgery is sometimes necessary.

What can you do?

Because critically ill patients often can't communicate very well, family members can be crucial to helping doctors solve the diagnostic puzzle.

First, be sure you know the medical history of your loved one. Older patients, especially, may not be able to list their medications or recall their own medical history — let alone their family's. Doctors may "roll their eyes" when family member comes in with a sheaf of papers or a brown bag stuffed with their loved one's meds, says Winters, but when faced with a difficult diagnosis, any and all information can be "incredibly valuable."

Second, says Newman-Toker, have your "story" ready. Once at the hospital, patients and their families are asked repeatedly to explain what happened. Never assume that the emergency room nurse, say, has conveyed all the right details to the doctor in the ICU. Keep a good track of the problem, including when symptoms developed and what's been done since you arrived at the hospital.

Third, be sure to ask the doctor questions, with the goal of figuring out "whether the doctor is thinking clearly or not," says Newman-Toker. While most laypeople don't have the medical expertise to second-guess the doctor, "they can gauge the extent [to which] the doctor is being curious, meticulous and thoughtful."

Finally, if your gut is telling you something is wrong, "push the doctors to keep looking," Winters says. When family members advocate for their loved ones, physicians are more likely to push beyond their foregone conclusions to get the diagnosis right.

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