People who went to the hospital with traumatic brain injuries were more likely to survive if they had marijuana in their system, according to a new published report by Los Angeles Biomedical Research Institute.

The study, published in the October edition of The American Surgeon, was drawn from the records of trauma patients admitted to County Harbor-UCLA Medical Center near Torrance from 2012 through Jan. 1, 2010 through 2012. LA BioMed, as it’s commonly called, is an independent research institute on the campus of the hospital.

“Previous studies in animals showed that giving tetrahydrocannabinol (THC), the active compound in marijuana, would improve survival after a traumatic brain injury,” said David Plurad, an LA BioMed researcher, Harbor-UCLA critical care physician and co-author of the report, titled “Effect of Marijuana Use on Outcomes in Traumatic Brain Injury.” “We’ve known that in humans this may also be the case.”

Plurad and a team of fellow doctors and medical students reviewed 446 records of patients who sustained a brain contusion or other traumatic brain injury and were also screened for illicit drugs, which is a test done on many trauma patients so doctors can properly treat them.

Patients with marijuana in their system constituted 18.4 percent of the total study group. Both groups suffered similar levels of injury, but the group that tested positive for THC mostly consisted of men in their 20s to 40s. The other group was older, on average by about 20 years.

Only 2.4 percent of those who tested THC-positive died in the hospital as a result of their injuries while 11.5 percent of the patients who did not have THC in their system died.

Previous studies have linked marijuana use to reductions in pain and anxiety, increased appetite, reduced ocular pressure and decreased muscle spasms, among other health benefits. But no one has previously been able to measure the effects of natural forms of marijuana in the system at the time of a traumatic brain injury.

“This study was one of the first in a clinical setting to specifically associate THC use as an independent predictor of survival after traumatic brain injury,” Plurad said. “It’s illegal to give THC in its natural form for research purposes so this is really the best you can do in a natural environment. There’s a big difference between synthetic forms of THC and the natural form.”

Though researchers don’t have answers on a cellular level for why marijuana seems to have neuro-protective qualities, Plurad said THC seems to reduce inflammation and swelling processes that the body undergoes after a trauma. Intracranial pressure is one of the biggest challenges surgeons face when dealing with brain injuries, and marijuana’s potential to reduce brain swelling could bring medical advances, he said.

If marijuana is decriminalized, researchers would have an easier time studying the federally controlled plant, and Plurad said he looks forward to that because he believes it could improve they way physicians treat and understand pain.

“It’s important to treat pain and anxiety right away, especially in brain injury,” Plurad said. “Appropriate pain control and sedation should be used early. This study shows that it may be the pain-control effect of the THC that’s preventing inflammation.”