Grammy-winning Tejano singer Emilio Navaira may not survive a severe brain injury suffered when his tour bus slammed into traffic barrels on a Houston interstate, his neurosurgeon said Monday.

"There is a chance he may not make it," said Dr. Alex Valadka, director of neurotrauma services at Memorial Hermann in the Texas Medical Center and vice chairman of neurosciences at the University of Texas Health Science Center at Houston.

"Everyone needs to understand that right upfront. That's how bad it is."

Valadka and his team operated for two hours to remove a blood clot that was putting pressure on Navaira's brain after the singer was brought to the hospital following the wreck before dawn Sunday.