(CNN) -- When your kid needs surgery, your response is probably, "Do whatever is necessary to fix him NOW. We'll worry about later, later." But it turns out that putting a child under anesthesia may increase the risk of long-term damage to his or her ability to think.
A new study published by the American Academy of Pediatrics concludes that exposure to anesthesia before age 2 may manifest in a form of cognitive impairment called apoptotic neurodegeneration. But let's not get ahead of ourselves. First of all, the researchers found no greater risk in those subjects who had only been "put under" once. Multiple exposures to surgery/anesthesia, on the other hand, significantly increased the risk of developing learning disabilities later on in life.
The estimated incidence of learning disabilities, as measured at age 19, was 21.3% for kids who'd not had anesthesia, 23.6% for those exposed once, and 36.6% for those with multiple exposures, according to the study.
But what other factors might be at play? For starters, as noted in the study itself, "...the underlying condition necessitating the surgery or a coexisting disease that could confound the relationship between anesthesia/surgery and neurodevelopmental outcomes."
Indeed, it's impossible to control for the influence of the surgery itself, says Dr. David Reich, chairman of anesthesiology at Mount Sinai School of Medicine. "Surgery causes trauma to tissues, inflammation, and blood loss. Postoperatively, there are variable degrees of inflammation, disability, and pain. The skill of the surgeon and the experience of the team before, during, and after surgery all vary widely and are difficult to quantify."
Furthermore, asserts Reich, "anesthesia is not a 'black box.' There are wide differences in blood pressure, oxygen, carbon dioxide, and levels of acidity that influence brain blood flow and flow to other tissues of the body." In fact, many of the drugs and techniques used today were not even available when these surgeries currently under review took place back in the 1970s and '80s. Halothane, for example, then the predominant anesthetic agent for children, is now rarely, if ever, used in the United States, says Reich.
To arrive at their results and draw this new conclusion, the Mayo Clinic's Dr. Randall Flick and his colleagues analyzed more than 8,500 participants from one town in Rochester, Minnesota, born between January 1976 and December 1982. The data analysis was fully adjusted for health status by taking advantage of access to complete medical charts for all members of the study. Children who did not provide research authorization, left the district before age 5, or tested severely intellectually disabled were excluded from the sample.
And perhaps the timeframe during which these surgeries took place is the most important caveat to note. This new study is a study of association. "Despite the fact that data were collected prospectively," says Reich, "this is retrospective research, because the idea for the research emerged decades later. Even with strong independent statistical findings, there is no way to be certain in a retrospective cohort study that the observations were not influenced by some [other] factor not studied, such as blood loss during surgery."
The bottom line: Knowing that young brains are especially susceptible to the affects of anesthesia, some early surgeries might be delayed, thereby preventing future learning disabilities in some children.