By Denise Mann
MONDAY, Oct. 3 (HealthDay News) -- Children younger than 2 who undergo multiple surgeries requiring general anesthesia may be up to three times more likely than other children to develop speech and language problems as they grow up, a new study suggests.
However, experts cautioned that the finding appears to be restricted to very small children who require more than one surgery.
"A single exposure to anesthesia in surgery has not been shown to be problem, so parents can be reassured that this is not likely to cause any problems," said study author Dr. Randall Flick, an associate professor of anesthesiology and pediatrics at the Mayo Clinic in Rochester, Minn. "For children who have or will have repeated exposures to anesthesia, it's important that those families have a conversation with the surgeon and anesthesiologist to determine the risks and benefits in a broad context."
The new findings are published in the November issue of Pediatrics.
According to the researchers, many animal studies have suggested that certain anesthetics may cause brain changes that might affect learning and behavior, and the U.S .Food and Drug Administration is currently looking into this issue.
"The animal studies show injury to the brain, and deficits in learning and memory in monkeys who are now age 4, and our study in this context becomes concerning," Flick said.
In their new research, Flick's team compared the rate of learning disabilities among 350 children who had undergone surgery with general anesthesia before their second birthday -- including 64 kids who had undergone more than one surgery -- to that of 700 children who did not have any such procedures with anesthesia.
All of the children were born between 1976 and 1983 in one school district in Rochester, Minn. Children who had more than one surgery before age 2 were at heightened risk for speech and language-related learning disabilities by the time they reached the age of 19, but not for behavioral disorders, the study found. Almost 37 percent of children who had experienced such surgeries multiple times developed a learning disability, compared to just over 21 percent of kids who had never had surgery with anesthesia before age 2.
There was no significant increase in risk for learning problems in kids who had undergone just one surgery, the team said.
Learning disabilities were diagnosed based on performances on standardized tests.
Dr. Lynne G. Maxwell, a pediatric anesthesiologist at the Children's Hospital of Philadelphia, said the possibility of a link between learning troubles and surgery and/or anesthesia is one doctors are currently grappling with. She noted that since the children in this study were born, there have been many changes in the types of anesthesia used on kids, as well as improvements in monitoring.
"Back then we tended to give gas, but now anesthesiologists use less gas and instead use other anesthetics, including nerve blocks and pain medications," said Maxwell, who was not involved in the study.
Closer monitoring of children during surgery has changed the playing field, too, she said. "Back then, it didn't exist and it's entirely possible that these children had low blood oxygen levels [during surgery] or other complications that we didn't monitor for," she explained.
In any case, parents should not postpone essential surgeries due to fears about anesthesia and learning disabilities, she said.
"Parents often ask if there is a 'magic combination' that will reduce this risk, if there even is such a risk, and we don't know," Maxwell said. "It is very reassuring that [having just] one surgery was not a problem."
As for children who require two or more surgeries before the age of 2, they "usually have serious health problems and I would hate to have parents who are already worried about a child to feel that they should choose not to have a surgery because of the possible risk of developmental problems," Maxwell said.
Dr. Richard J. Levy, a pediatric anesthesiologist at Children's National Medical Center in Washington D.C., agreed, stressing that a causative link has not yet been proven.
He believes there are other plausible explanations for the study's finding, including the notion that children who have multiple surgeries before age 2 have abnormal brain development to begin with.