More than one exposure to general anaesthesia puts infants at twice the risk for learning disabilities later on compared to children never exposed to the drugs, a new study suggests.
The results add to mounting evidence from animal and clinical studies that anaesthesia might injure young developing brains. In young animals, anaesthetic drugs cause the normal process of pruning extra brain cells to become more pronounced and widespread, and the animals end up with learning and behaviour problems later in life.
"There's a persistent association between multiple anaesthetic exposures during the first two years of life and subsequent problems with learning," lead author Dr Randall Flick of the Mayo Clinic in Rochester, Minnesota, told Reuters Health.
Whether the anaesthesia is actually causing those disabilities is not clear, and experts caution that the results should not influence decisions to treat children who need painful procedures.
Adequate surgical care
"This should not get in the way of having children receive adequate surgical care," said Dr Bob Rappaport, head of the US Food and Drug Administration's Division of Anaesthesia, Analgesia and Addiction Products.
Dr Flick and his colleagues compared 350 children who had received one or more doses of anaesthesia before the age of two for short term conditions or minor procedures to 700 children who had never been put under.
All of the children were healthy; none had chronic illness, according to a report online in Paediatrics.
81 children in the anaesthesia group developed a learning disability before the age of 19, compared to 138 children in the control group.
Disability rates the same
Rates of disability were about the same among children who had undergone one procedure with anaesthesia and those who had never been exposed – roughly 23% and 21%, respectively.
But among children who had had two or more procedures with general anaesthesia, 36% had a learning disability.
Dr Rappaport told Reuters Health the FDA is working to accelerate research on anaesthesia in children. Dr Flick is a member of an FDA advisory panel on the subject.
Delayed surgery greater risk
The current study, which was funded in part by the FDA, does not conclusively show that the drugs are to blame for the children's learning problems. And the authors acknowledge that the study's observational nature makes it impossible to separate the influence of the surgery itself from that of the medication.
For now, the panel recommends no change in the way anaesthesia is used in children.
"The risk of delaying surgery would be greater than the risk of anaesthesia exposure," Dr Flick told Reuters Health.
(Reuters Health, October 2011)