The finding:
The study examines the association between undergoing general anesthesia before the age of three and neurodevelopmental outcomes. The authors used data from a national database in Taiwan, with data from hospitalizations from 1997-2008, and follow up neurodevelopmental outcome data through 2013. The study included a total of 43,377 children, with 2261 patients having undergone anesthesia, and a 2:1 matched control by age, sex, and hospitalization date cohort of 4522 children. They found that general anesthesia was correlated with developmental delay (HR = 1.30; 95% CI=1.09–1.55) but not with ADHD, ASD, tic disorders, or intellectual disability.

Strength and weaknesses:
This study’s strengths include having data from a large number of patients across a whole country for about a decade. A limitation is that the study only included patients in Taiwan, which may limit its generalizability. Additionally, the study controlled for some factors, such as age, sex, date of hospitalization, and allergy related diagnoses. However, the investigators did not control for other diagnoses that may be independently related to developmental delay such as heart or genetic conditions. There were also variable amounts of time for follow up of the subjects, with some patients having a follow up of a maximum of 15 years and others a maximum of 5 years, as the end-point was a specific date of 12/31/13. They also excluded patients with pre-existing history of a number of conditions, including prematurity, brain tumors, other congenital system abnormalities, epilepsy, cerebral palsy, ADHD, developmental delay, ASD, tic disorder, and intellectual disability, which additionally limits generalizability. They also did not control for type of procedure or medication used for anaesthesia, which the authors note be helpful in the future to examine.

Relevance:
For children admitted to a hospital, general anesthesia is a relatively common exposure. As consult-liaison psychiatrists, it is important to be able to be knowledgeable about and help educate families and practitioners about possible psychiatric-related complications of common medications and procedures. This study adds to the evidence that undergoing general anesthesia at a young age may carry risk of adverse neurodevelopmental outcomes. However, the study also has a number of limitations and further study is warranted.