The research, published in the journal Pediatrics, comes against the backdrop of two trends: the rising rate of concussion-related ER visits by younger kids, and the exploding use of CT, or computed tomography, scans, despite growing concerns about the high dose of radiation and heightened cancer risk they pose. The number of diagnostic CT scans ordered on patients in the United States-- roughly 70 million per year at last count--has grown more than 23-fold since 1980. A December 2009 study estimated that because the scans often deliver high doses of ionizing radiation, the growth in their use would cause thousands of additional cancers and14,500 more deaths each year.
For children, the danger of overusing CT scans is particularly worrisome, because children's tissue is more sensitive to ionizing radiation's effects, and because they have a longer lifespan ahead in which to develop cancers. In ordering a cranial CT scan on a child with apparent concussion, physicians face a particular dilemma: They must weigh the possibility that radiation could sow the seeds of brain malignancies down the road against the more immediate prospect that trauma to the child's brain could cause dangerous swelling or bleeding into the brain that might not be evident without the use of the sophisticated brain imaging technique.
In the latest study, researchers reviewed the clinical records of some 40,000 children brought to 25 different emergency rooms across the country with suspected brain injury. These children were generally alert, but may have lost consciousness briefly, become disoriented, vomited or complained of headache or dizziness. In such cases, physicians' practices varied widely: Some participating doctors immediately ordered CT scans in 93% of such cases; others did so in 71% of such instances.
But in cases where the physician ordered a period of observation before deciding on whether a CT scan should be done, children were 11% less likely to get a CT scan than in cases where the scan was ordered immediately. And children in this watchful-waiting group were no more likely to develop dangerous post-concussion complications than were kids who were sent immediately to get a CT scan. For every 1,000 children being assessed for traumatic brain injury, a period of observation before a decision is made on CT scan could result in 39 fewer such scans--and a lot less radiation for some--the researchers estimated.
"Clinical observation before making a decision regarding CT use seems to be a safe and potentially effective strategy to manage a subset of children with blunt head trauma," the group reported. The researchers cautioned, however, that their research fails to determine how long a young patient should remain under observation by medical staff before he or she is released. The researchers also acknowledged that holding pediatric patients for hours while waiting to see if their symptoms worsened could exacerbate emergency department crowding, a growing problem across the country.