Dennis Quaid's twin babies involved in L.A. hospital drug overdose

While the hospital declined to release the identities of the three patients, Quaid's representatives said two of the patients were the actor's children, Thomas Boone and Zoe Grace.

The hospital declined to release their conditions Wednesday, citing privacy laws.

A Cedars-Sinai official said in a statement late Tuesday that tests indicated there were no adverse effects on the patients but he issued an apology to their families.

"This was a preventable error, involving a failure to follow our standard policies and procedures, and there is no excuse for that to occur at Cedars-Sinai," said chief medical officer Michael L. Langberg.

The statement did not specify which policies and procedures were violated or who was involved.

"Although it appears at this point that there was no harm to any patient, we take this situation very seriously," he said, promising to take all steps to ensure it never happens again at Cedars-Sinai, a highly regarded medical research center.

"Dennis and Kimberly appreciate everyone's thoughts and prayers and hope they can maintain their privacy during this difficult time," Quaid's publicist, Cara Tripicchio, said in a statement Tuesday.

Suanne Buggy, a state Department of Public Health spokeswoman, said the agency was conducting a "comprehensive investigation" after receiving reports about an incident involving newborn twins at Cedars-Sinai. Buggy declined to elaborate, citing the ongoing investigation, but she said the results would be made public.

According to Langberg, three patients on Sunday each received vials containing 10,000 units per milliliter of heparin, a blood thinner, instead of vials with a concentration of 10 units per milliliter. The patients were receiving intravenous medications and the heparin was used to flush the catheters to prevent clotting.

Once the hospital staff realized the error, they did tests to measure the patients' blood clotting function, Langberg said. One patient's test was normal, but the other two were given another drug, protamine sulfate, that reverses the effects of heparin. Experts said protamine sulfate is generally effective in restoring normal clotting function.

Further tests on the two "indicated no adverse effects from the higher concentration of heparin," Langberg said. "Doctors continue to monitor the patients."

"I want to extend my deepest apologies to the families who were affected by this situation," Langberg said.

Steven Kayser, professor of clinical pharmacy at the University of California, San Francisco, said heparin comes in different concentrations and giving a little too much can be disastrous.

"Heparin is a good drug, but you have to pay very careful attention because of the varying concentrations," he said.

Last year, three premature infants at an Indiana hospital died after a pharmacy technician mistakenly stocked the medicine cabinet with heparin vials containing a dose 1,000 times stronger than what the babies were supposed to receive. Three others also suffered overdoses but survived.

In February, Baxter Healthcare Corp. sent a letter warning health care workers to carefully read labels on the heparin packages to avoid a mix-up in light of the Indiana overdose deaths. The Food and Drug Administration also posted the letter on its Web site.

Founded in 1902, Cedars-Sinai employs more than 2,000 doctors. This year, it was ranked by U.S. News & World Report as the 17th-best hospital out of more than 5,000 U.S. medical centers.

Quaid and his wife are the biological parents of the twins, who were born Nov. 8 to a surrogate mother.

"God has definitely blessed us," the couple said in a statement announcing their birth.

Quaid, 53, has a 15-year-old son, Jack Henry Quaid, from his marriage to Meg Ryan.

His screen credits include "Great Balls of Fire!" "Any Given Sunday" "The Big Easy" and "Far From Heaven."