There is inconclusive evidence that exposure to anesthesia in early life is associated with learning disability in school. (Image source: Thinkstock)

There is inconclusive evidence that exposure to anesthesia in early life is associated with learning disability in school. (Image source: Thinkstock)

When infants are exposed to anesthesia, does it affect learning abilities later in life?  In neonatal animals, exposure to an anesthetic is unambiguously associated with neuroapoptosis (cell death) in the brain.  Human studies have not been as unambiguous.

Dr. Choon Bong, Department of Paediatric Anaesthesia, KK Women’s and Children’s Hospital, Yong Loo Lin School of Medicine, Singapore and colleagues analyzed 100 full-term children who underwent sevoflurane anesthesia for inguinal herniotomies, circumcisions, cystoscopies, and pyloromyotomies before their first birthday who were then studied when they were twelve years old.  Their study titled “The Effects of Exposure to General Anesthesia in Infancy on Academic Performance at Age 12” was published in this month’s issue of Anesthesia & Analgesia.

The control group consisted of children born at full term with no significant comorbidities who did not receive anesthesia or sedation.  This retrospective study took place in Singapore where all children who attend state school take an examination when they are twelve years old.  Learning disability was diagnosed either by parental report or based on formal diagnosis.

Anesthesia induction was with thiopental or sevoflurane and all children received sevoflurane for anesthesia maintenance.  Twelve years later, the results on the standardized test were no different between children who received anesthesia and the control group.

However, children with a learning disability scored lower if they also received anesthesia.  More children with a learning disability diagnosed by parental report were exposed to anesthesia (27 of 100) than the control group (5 of 106).  Fifteen children in the exposed group had a formal diagnosis of learning disability compared to 4 in the control group.  When a stepwise logistic regression analysis was performed to determine potential predictors of learning disability, only previous anesthesia exposure was a significant predictor.  The odds ratio of having a formal diagnosis of learning disability in exposed children compared to controls was 4.5.

The study was limited by the small size, and by the retrospective design. Additionally, learning disability was not rigorously defined.  Furthermore, three of 15 children with a formal diagnosis of learning disability could not take the exam due to their disability. This may also be why overall results on the standardized test were no different.