CT Scan Usage Zooms At Hospital ERs

Hospital emergency rooms in California are  performing increasingly more CT scans on patients with minor injuries, part of a nationwide trend that has some medical experts worried about the potential long-term health impact.

The analysis of more than 8.5 million patient records by UC San Francisco and Stanford University researchers was eye-opening: Hospital ERs were more than twice as likely to perform at least one CT scan on a patient with minor trauma in 2013 than in 2005, less than a decade ago. The prevalence rose from 3.5% of patients to 7.17% three years ago. Although there had been a slight dip in usage in 2011, it began rising sharply again in 2012.

“The reasons for this increase are multifactorial,” said Renee Hsia, M.D., a professor of emergency medicine and health policy at UCSF and the study's senior author. “They range from defensive medicine practices, the superior diagnostic accuracy of CT scans compared with x-rays, to their increased availability and convenience in emergency departments, and the demand to expedite discharge of patients.”

Not every hospital in California ramped up their use of CT scans. According to the study, which was just published in the Journal of Surgical Research, 39% of all the scans ordered were done so by level one and two trauma centers, compared to just 3% at hospitals that did not have a trauma center designation.

Groups of patients were also more likely to undergo scans, particularly those between the ages of 18 and 24, adults most vulnerable to suffering aftereffects of radiation exposure because of the many years they expect to live, and those over the age of 45.

“With the aging of the U.S. population, physicians may be influenced toward greater advanced imaging even in the case of low-mechanism injuries, given the atypical presentations and more serious pathology that older adults may have,” Hsia said.

Although CT scans have been hailed by the medical community as being far for accurate for diagnosing injuries than traditional x-rays, the ongoing increase in their use has had medical professionals worried in recent years. In 2009, the U.S. Food and Drug Administration issued an advisory about the overuse of such scans. That was linked to an improperly calibrated device at Cedars-Sinai Medical Center in Los Angeles that led to more than 200 patients receiving eight times the normal doses of radiation from CT brain perfusion scans to check for strokes.

That incident aside, there has been significant debate about whether CT scans are being overused in general. In 2013, the American College of Emergency Physicians (ACEP) added the use of unnecessary head scans to the American Board of Internal Medicine's “Choosing Wisely” list of overused medical procedures.

Yet a study conducted last year by the Advisory Board concluded that among ER patients who complain of headaches, fainting or minor head trauma, four out of five of the CT scans they underwent did not comport with the “Choosing Wisely” guidelines.

“In other words, most of these scans—which are costly—were administered even though patients didn’t need them, the results didn’t inform the course of care, and each scan exposed the patient to radiation unnecessarily,” Advisory Board Executive Director Michael Koppenheffer said of his organization's analysis.

The UCSF/Stanford study did not delve into whether there is a financial component that may be prompting hospitals to perform more CT scans. However, chargemaster data filed with OSHPD indicate that hospitals may charge many times more on average to perform a scan than an X-ray. 

At Cedars-Sinai, for example,  the average charge for an abdominal CT scan with contrast is $4,803, versus $1,003 for a lower-back x-ray with four views. 

At UCSF Medical Center, the average charge for a CT abdominal scan with contrast was $3,377 in 2015. A lower back x-ray with four views is $338. 

 “I think it would be rare for that to be a part of the decision-making process for an emergency physician, Hsia said of the economic considerations.

But she and her fellow researchers noted that there is a health risk of undergoing a CT scan – about one in 2,000 patients may later experience a fatal cancer associated with their scan.

“The message for both patients and physicians is that there are long-term risks associated with radiation exposure and there may be situations where imaging is not definitively warranted or beneficial,” Hsia said. “We can’t conclusively say which cases should not involve imaging, since every patient and every circumstance is different, but given that it is getting easier and easier to get CT scans, we need to be cautious in weighing their risks and benefits.”