Numerous preclinical studies have shown that general anesthetics adversely influence the development of young brains. These adverse effects are dose-dependent occurring in specific stages of brain development. Histologic examinations show increased apoptosis, pathological neurogenesis and dendritic formation after exposure in infant animals to virtually all general anesthetics at a clinically effective dose which are associated with memory and behavioral changes at adulthood.


Clinical research into the long-term effects of anesthesia during early childhood on brain development is mainly limited to retrospective cohort studies, with conflicting results. Only recently, the interim analysis of a prospective randomized clinical trial examining the effects of general anesthesia has been published. In this GAS-study the influence up to 1 h of general anesthesia versus regional anesthesia in young infants has been assessed on the neurocognitive functioning at the age of 2 years. No differences were found between the two groups. However, the primary outcome analysis which is the 5-year outcomes will not be complete until 2018.


Pending clear evidence, anesthesiologists should discuss the indication of anesthesia for surgery and diagnostic procedures with caregivers and parents taking into consideration the risks and benefits of the planned procedure.