The impact of early exposure to general anesthesia on visual and neurocognitive development

Every year millions of children are exposed to general anesthesia while undergoing surgical and diagnostic procedures 126 Sun L. Early childhood general anaesthesia exposure and neurocognitive development. BJA Br J Anaesth. 2010; 105: i61-i68https://doi.org/10.1093/bja/aeq302 Abstract Full Text Full Text PDF PubMed Scopus (274) Google Scholar ,33 DeFrances CJ Cullen KA Kozak LJ. National Hospital Discharge Survey: 2005 annual summary with detailed diagnosis and procedure data. Vital Health Stat. 2007; 13: 1-209 Google Scholar ,65 Inge TH Zeller MH Jenkins TM et al. Perioperative outcomes of adolescents undergoing bariatric surgery: the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study. JAMA Pediatr. 2014; 168: 47-53https://doi.org/10.1001/jamapediatrics.2013.4296 Crossref PubMed Scopus (179) Google Scholar . In the field of ophthalmology, 44,000 children are exposed to general anesthesia annually for strabismus surgery alone 39 Dombrow M Engel HM. Rates of strabismus surgery in the United States: implications for manpower needs in pediatric ophthalmology. J AAPOS Off Publ Am Assoc Pediatr Ophthalmol Strabismus. 2007; 11: 330-335https://doi.org/10.1016/j.jaapos.2007.05.010 Abstract Full Text Full Text PDF Scopus (9) Google Scholar . While it is clear that general anesthesia is necessary for sedation and pain minimization during surgical procedures, the possibility of neurotoxic impairments from its exposure is of concern. In animals there is strong evidence linking early anesthesia exposure to abnormal neural development 70 Jevtovic-Todorovic V Hartman RE Izumi Y et al. Early exposure to common anesthetic agents causes widespread neurodegeneration in the developing rat brain and persistent learning deficits. J Neurosci Off J Soc Neurosci. 2003; 23: 876-882 Crossref PubMed Google Scholar , but in humans the effects of anesthesia are debated. In humans many aspects of vision develop within the first year of life, making the visual system vulnerable to early adverse experiences and potentially vulnerable to early exposure to general anesthesia. We attempt to address whether the visual system is affected by early postnatal exposure to general anesthesia. We first summarize key mechanisms that could account for the neurotoxic effects of general anesthesia on the developing brain and review existing literature on the effects of early anesthesia exposure on the visual system in both animals and humans and on neurocognitive development in humans. Finally, we conclude by proposing future directions for research that could address unanswered questions regarding the impact of general anesthesia on visual development.