Children ages three and younger who undergo anesthesia are at higher risk of developing learning disabilities later, according to a Mayo Clinic research report. The study is the first that suggests some effect of exposure to anesthesia among younger children, though it is unclear whether other factors, such as the physiological stress of surgery or other medical problems, that are responsible for the learning disabilities.
Researchers, led by Robert Wilder, M.D., Ph.D., a Mayo Clinic anesthesiologist, studied the medical records of more than 5,000 children born between 1976 and 1982. The team found that more than one exposure almost doubled the risk that a child would be identified as having a learning disability before age 19. The risk also increased with longer durations of anesthesia.
“It’s very important for parents and families to understand that although we see a clear difference in the frequency of learning disabilities in children exposed to anesthesia, we don’t know whether these differences are actually caused by anesthesia,” says Randall Flick, M.D., a Mayo Clinic anesthesiologist and co-author of the study. Young children’s brains are more vulnerable to a variety of problems because they are undergoing dynamic growth. The brain is rapidly forming connections between cells and trimming excess cells and connections, says Dr. Wilder.
The general anesthesia chemicals in use during the study period were primarily halothane and nitrous oxide (laughing gas). Although halothane is no longer used in the U.S., it has been replaced by newer agents that have similar effects on the brain. Nitrous oxide is widely used throughout the U.S. and the world.