Children who have a general anaesthetic in the first four years of life have substantially worse literacy and numeracy skills a new study has found.

University of Sydney researchers compared the developmental and NAPLAN results of nearly 38,880 children who had a general anaesthetic to 197,301 who had no exposure to anaesthetic.

Compared to children with no exposure to general anaesthesia, those exposed to general anaesthesia had a:

  • 17 per cent increased risk of poor child development
  • 34 per cent increased risk of lower numeracy scores on school tests
  • 23 per cent increased risk of lower reading scores on school tests.

The children were born in New South Wales at 37-plus weeks’ gestation without major congenital anomalies or neurodevelopmental disability.

When the researchers restricted their analyses to children who’d had only one hospitalisation involving a procedure requiring general anaesthesia, they found no increased risk for poor development or reduced reading scores, however the risk of poor numeracy scores remained.

“There are many reasons why a child requires surgery or investigation, and, in some cases, this may be lifesaving or unavoidable,” said the study’s senior author, Professor Natasha Nassar of the University of Sydney.

“For these children, our findings suggest that it is important to follow-up and monitor their literacy and numeracy skills when they reach school, and ensure early intervention, if required.”

Sydney University clinical lecturer, a senior staff specialist in paediatric anaesthesia at Sydney’s Children’s Hospital, Westmead, Dr Justin Skowno, co-author of the study report, said determining exactly what was causing this effect is not easy.

Associated medical conditions

“The children receiving a general anaesthetic in this study also had surgery, and often had other associated medical conditions.

“There are some procedures where alternative approaches or management may be possible, but the majority of surgeries in young infants and children cannot easily be postponed.”

“Parents can certainly discuss with their doctor and explore whether these procedures can be avoided, combined with other procedures, delayed to older ages or treated with alternatives to surgery, or other methods of sedation,” said Dr Skowno.

Further investigation

The researchers say further investigation of the specific effects of general anaesthesia on numeracy skills, underlying health conditions that prompt the need for surgery or diagnostic procedures is required, particularly among children exposed to previous or long duration of general anaesthesia or with repeated hospitalisations.

Child development was obtained from the Australian version of the Early Development Instrument (AvEDI), a nationwide triennial assessment of child development.

It includes results from teachers’ assessment of five developmental domains: physical health and well-being, emotional maturity, communication skills and general knowledge, language, and cognitive skills (numeracy and literacy) and social competence.

Based on national percentiles, children with domain scores in the bottom 10 per cent are classified as developmentally vulnerable in that domain. Children who are vulnerable in two or more domains are classified as developmentally high risk.

Children’s Grade 3 school performance was ascertained from the NSW Department of Education National Assessment Program-Literacy and Numeracy (NAPLAN) conducted in public schools in 2009- 2014.

NAPLAN tests cover five. domains: reading, writing, spelling, grammar and punctuation, and numeracy.