New guidelines on how to manage concussions during athletic play offer a simple message for doctors and coaches if their players get a head injury: when in doubt, keep them out.
Researchers at the American Academy of Neurology say they've spent thousands of hours reviewing all scientific studies published through June 2012 to come up with their latest recommendations, which replace the medical society's 1997 concussion guidelines.
Those older guidelines had assigned grade scores based on concussion severity, with ranged from Grade 1 -- described by players as having their "bell rung" - to Grade 3 concussions, which caused loss of consciousness. A person with a Grade 1 concussion would be allowed back in to the game if they were symptom-free within 15 minutes, according to those guidelines, while one with a Grade 3 concussion may have to wait a week or two.
The new set, however, moves away from those grades completely and urges doctors to diagnose each case on an individual basis. They were published March 18 in the academy's journal, Neurology.
"Among the most important recommendations the Academy is making is that any athlete suspected of experiencing a concussion immediately be removed from play," co-lead guideline author Dr. Christopher C. Giza, a neurologist at the David Geffen School of Medicine and Mattel Children's Hospital at UCLA, said in a news release. "There is no set timeline for safe return to play."
An estimated 3.8 million athletes sustain a sports-related traumatic brain injury each year in the United States, many of whom seek no immediate medical treatment. The new guidelines say athletes with a suspected concussion should be lifted from the game immediately and can't return until a licensed health care professional trained in concussions allows them to return to play -- slowly -- after all symptoms are gone. The evidence reviewed by the guideline authors showed kids take longer to recover from a concussion than college athletes, so a more conservative approach is recommended when deciding if a child or teen athlete should return to play.
Signs and symptoms of a concussion include a dazed stare, headache, sensitivity to light and sound, changes to reaction time, balance, memory, speech (like slurring), judgment and coordination. Contrary to common perception, loss of consciousness -- or a "blackout" -- only occurs in less than 10 percent of cases. Doctors and other licensed health professionals should use a checklist while looking for these symptoms and whether the athlete has a history of concussions at a younger age, which may make recovery take longer.
Some sports are more likely to cause a concussion than others, the researchers added. Concussion risk is greatest in football and rugby, followed by hockey and soccer. There is no clear evidence that one type of mouth guard or helmet can better reduce risk than another, so the academy urges football players to make sure their helmet fits properly and is well-maintained.
Young women and girls are at the greatest risk for a concussion when playing soccer and basketball, according to the guidelines.
The sports with the lowest risk for concussions include baseball, softball, volleyball and gymnastics.
Athletes who have suffered a concussion are at significant risk for getting another concussion within 10 days. That's another reason it's so important to have a professional check for symptoms.
"If in doubt, sit it out," urged Dr. Jeffrey S. Kutcher, an associate professor of neurology with the University of Michigan Medical School in a press release. "If headaches or other symptoms return with the start of exercise, stop the activity and consult a doctor."
The guidelines also touched on the long-term health risks professional athletes are facing from having histories of concussions or longer exposure in their sports. Those who have the ApoE4 gene, which has been linked to Alzheimer's risk, also appear to be at greater risk for cognitive impairment following their playing days, such as chronic traumatic encephalopathy (CTE).
The only modifiable risk factor that professional athletes have at this time is to reduce exposure to future concussions or contact sports, the guidelines concluded.
The academy's new guidelines are endorsed by the NFLPA (player's association) and National Athletic Trainers Association, among other groups.
Dr. Richard Figler, a sports medicine specialist at the Cleveland Clinic, told CBSNews.com in an email that the new guidelines are positive step forward because the academy uses the latest evidence.
"We are learning more and more about concussions on a day-to-day month to month and year to year basis," said Figler. "We are not done learning quite yet but these guidelines being updated on a regular basis will help everyone taking care of concussions be better informed to do so."
The bottom line for these guidelines, according to the authors, is to keep athletes of all ages off the field if there's any chance they still have lingering symptoms from a head injury.
Said Kutcher, "You only get one brain; treat it well."
More information on concussions and the new guidelines can be found at the American Academy of Neurology's website.