Significant drops in blood oxygen levels are more common than previously thought in patients undergoing an epileptic seizure, and may be linked to sudden, unexplained death in epilepsy, according to a report from UC Davis neurologist Masud Seyal and colleagues Lisa Bateman and Chin-Shang Li.

Seyal and his colleagues examined records of 300 seizures in 57 epilepsy patients with chronic, recurrent, unprovoked seizures. One-third of all seizures were associated with drops in blood-oxygen levels below 90 percent.

The findings suggest that some cases of SUDEP may result from the brain not signaling the patient to continue breathing during seizures, though more conclusive evidence is needed, Seyal said.

The results show that hospitalized patients being monitored for seizures should have both continuous blood-oxygen monitoring and round-the-clock observation by staff or relatives.

More detailed story here; the original paper is published in the journal Brain.

Seyal is director of the UC Davis Comprehensive Epilepsy Program.