Anesthesia risk worries scientists

WASHINGTON (AP) -- Anesthesia can be harmful to the developing brain, studies on animals suggest, raising concerns about potential risks in putting young children under for surgery.
Food and Drug Administration scientists stressed Thursday they have no evidence that anesthesia and sedation drugs, which have been commonly administered for decades, can cause brain damage in children.
But numerous animal studies find that a majority of the drugs typically used to knock out children before surgery do kill brain cells in young rats, mice and -- preliminary results suggest -- rhesus monkeys.
"A safety signal has been identified in animals for many drugs used to provide sedation and anesthesia. This database is growing. The relevance of the animal findings to pediatric patients is unknown," Dr. Arthur Simone, an FDA medical officer, told experts gathered by the agency to discuss the issue.
Experiments on laboratory rats and other animals have shown that the drugs can lead to subtle but prolonged changes in behavior, including memory and learning impairments, according to a study published by FDA scientists this month in the journal Anesthesia & amp; Analgesia.
Scientists don't know if those study findings apply to children. Nor have comparable human studies been done that might provide answers.
Even detecting the effect of ketamine, halothane and other anesthetics on the central nervous system is difficult if not impossible in the young, according to the FDA. Unlike, say, fetal alcohol syndrome, there is no clear-cut collection of disorders associated with anesthesia exposure, said Dr. Bob Rappaport, head of the FDA's anesthesia office and one of the study's authors.
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