When infants or young children need surgery, does anesthesia affect their developing brains?

With more than 1 million children under age 4 requiring anesthesia for surgery in the United States each year, the Food and Drug Administration (FDA) and other health organizations are working together to answer this question.

Previous scientific studies in young animals have shown that commonly used anesthetics can be harmful to the developing brain. However, results have been mixed in children. Some studies of infants and young children undergoing anesthesia have reported long-term deficits in learning and behavior; other studies have not.

These conflicting results show that more research is needed to fully understand the risks anesthesia may pose to very young patients.