Lindsey Tanner, AP

The fear of missing something weighs heavily on every doctor's mind. But the stakes are highest in the ER, and that fear often leads to extra blood tests and imaging scans for what may be harmless ailments. Many ER doctors say the No. 1 reason is fear of malpractice lawsuits.

“It has everything to do with it,” said Dr. Angela Gardner, president of the American College of Emergency Physicians. The fast ER pace plays a role, too, as it's much quicker to order a test than to ask a patient lots of questions to make sure that test is really needed.

“It takes time to explain pros and cons. Doctors like to check a box that orders a CT scan and go on to the next patient,” said Dr. Jeffrey Kline, an emergency physician at Carolinas Medical Center in Charlotte, N.C. Patients' demands drive over-testing, too. Many think every ache and pain deserves a high-tech test.

“Our society puts more weight on technology than on physical exams,” Gardner said. “In other words, why would you believe a doctor who only examines you when you can get an X-ray that can tell something for sure?” Refusing those demands creates unhappy patients. And concern that unhappy patients will sue remains the elephant in the emergency room.

ER physicians are among the top 10 specialists most likely to be sued for malpractice, according to leading doctor and insurers groups. The Physicians Insurers Association of America, which represents almost two-thirds of private practice doctors, lists more than 600 lawsuits against ER doctors nationwide between 2006-08. That's about three percent of their clients.

Statistics vary by region, and chances of being sued generally are greater for several other specialties, including obstetricians, surgeons and internists. Still, the risk for a malpractice suit remains high in the ER because of the unique setting.

“When all hell is breaking loose, not a lot of doctors feel they can take the time to sit down with the patient,” said Texas family physician Dr. Howard Brody, an outspoken critic of excessive medical care. The result can be extra costs, and potential harm — including side effects from unneeded drugs and increased chances for future cancer from excessive radiation.

Gardner, who works in a Dallas emergency room, said she tries to talk patients out of tests she thinks they don't need, but usually without success. There are more than 116 million ER visits each year nationwide, national data suggest, and research suggests the number of visits is rising. The most common reasons adults go to emergency departments are abdominal or chest pain. Both can mean something harmless, or deadly.

To determine which it is, ER doctors turn to X-rays, CT scans and other imaging tests. In 2006, these were done for almost half of all emergency visits; blood tests were ordered for more than one-third of ER visits; medicine, including antibiotics, was given to 75 percent of patients.

One of doctors' biggest concerns with belly pain is appendicitis, and CT scans can confirm it. But the scans often are done in patients without classic symptoms. Dr. Angela Mills of the University of Pennsylvania said CT scans have reduced unnecessary surgeries. The trade-off is fewer surgeries and hospitalizations versus a test that costs several hundred dollars but which involves lots of radiation.

Missed heart attacks like Stacy Meaux's are the top reason patients sue emergency doctors. The 41-year-old Texas woman sought emergency treatment for chest pain at Christus St. Mary Hospital in Port Arthur, but doctors didn't think it was heart-related and sent her home. She fell dead of a heart attack several hours later. Her family won a malpractice lawsuit in January.

Meaux was overweight, with high blood pressure and diabetes when she died. Doctors did two electrocardiograms — a heart test using little sensors placed on the chest and elsewhere. They also checked Meaux's blood pressure, but skipped other heart tests, and sent her home with medicine for high blood pressure and asthma-like symptoms, court documents show.

A jury found Meaux's doctor and the hospital negligent and awarded her family more than $1 million in damages. A hospital spokesman said he couldn't comment because the hospital is appealing the verdict.

Patients with suspected heart attacks often get the range of what the ER offers, from multiple blood tests that can quickly add up in cost, to X-rays and EKGs, to costly CT scans, which are becoming routine in some hospital ERs for diagnosing heart attacks.

The battery of testing may be paying off. A few decades ago insurance statistics showed that about five percent of heart attacks were missed in the emergency room. Now it’s well under one percent, said Dr. Robert Bitterman, head of the American College of Emergency Physicians' medical-legal committee. “But you still get sued if you miss them,” Bitterman added.