Bret Michaels in Critical Condition

You've probably heard by now that Poison frontman and reality TV star Bret Michaels was admitted to the hospital on April 22 with complaints of a severe headache. Doctors found bleeding in his brainstem and Michaels was diagnosed with subarachnoid hemorrhage, or bleeding in the area between the brain and the thin tissues that cover the brain.

The 47-year-old singer, who has diabetes, had an emergency appendectomy a couple weeks ago; it's not known whether the diabetes or the recent surgery is related to his current condition. According to the LA Times, Michaels is under 24-hour surveillance as doctors work to find the source of the bleeding.