Updated

Some pediatricians are concerned that parents may delay important surgeries for their children after the FDA last week warned that certain uses of general anesthesia or sedation drugs in young children may harm brain development.

The warning focused on repeated use of general anesthesia in children under 3 years old, or a one-time use during surgery that lasts three hours or more. The Food and Drug Administration warning also applies to pregnant women in their third trimester.

Recent studies have found that a single use of anesthesia for a short period is unlikely to have negative effects, the FDA noted in its warning.

More than one million children a year in the U.S. under the age of 4 have surgeries that require anesthesia, according to the FDA. Only about 20 percent of those end up needing it again while they are still young, and even fewer children undergo surgeries that are three hours or longer, says David Warner, a pediatric anesthesiologist and professor of anesthesiology at the Mayo Clinic, in Rochester, Minn.

The majority of parents can be reassured about general anesthesia, says Dr. Warner, who expects many more parents of young children will have questions for him about its use.

General anesthesia is often used in children for tonsillectomies, placing of ear tubes and some gastrointestinal procedures -- surgeries that generally last less than two hours.

For longer surgeries, such as fixing a congenital heart problem, or repairing a cleft lip, which usually requires multiple operations, Dr. Warner says he already discusses with parents the potential negative impact of general anesthesia.

Randall Flick, president of the Society for Pediatric Anesthesia and a director of the Mayo Clinic Children’s Center, says the society worries that the FDA warning “may cause undue concern,” given that there are no clear alternatives to general anesthesia for certain surgeries.

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