I’ll admit I was skeptical when I heard Dennis Quaid was going to speak about medical errors (what does he know? I thought). But the actor really does know quite a bit about the horror of a medical mishap.

That’s because he lived it.

For about 41 hours last November, he and his wife watched as their newborn twins bled uncontrollably after they received 1,000 times the recommended concentration of the blood thinner heparin at Cedars-Sinai Medical Center in L.A.

Even though they had called the evening before and were told that their twins were “fine,” Quaid said, “The overdose was happening right under our noses.” His pediatrician and nurses knew there was a problem and didn’t tell them.

Nurses and pharmacy technicians failed to check the drug vials before administering the wrong dosage. The Quaid kids nearly died.

The story broke on the celebrity Web site TMZ, but as Quaid spoke to a room full of health journalists at Health Journalism 2008 in Arlington, Va. he said “it should have been a hard news story.”

In fact, a similar mistake killed three children in Indiana a year earlier. It happens more often than you think, Quaid told us. About 100,000 per year, his research showed.

In the hour-long, candid conversation, Quaid said that the experience motivated his family to start The Quaid Foundation, aimed at raising public awareness of medical errors.

“The source is always the same: seems to be human error,” Quaid said.

Now that his twins have recovered, he wants to look for ways to eliminate the human error by looking at the entire system, he said.

And, he wants to hear your medical error story. To tell it, visit the Quaid Foundation Web site: www.thequaidfoundation.org.