Attention deficit/hyperactivity disorder after neonatal surgery: review of the pathophysiology and risk factors

Abstract

There are many factors that influence the long-term neurological outcomes in children following cardiac surgery. Because there is also complex interaction between these many factors, it is difficult to assess which are primary and modifiable and which can be used to make improvements in outcomes. As survival after complex neonatal heart surgery has increased, the number of children with long-term neurological deficits is becoming more evident and this affects quality of life for children and their families.

One area of long-term assessment is the incidence of attention deficit/hyperactivity disorder (ADHD). The incidence rate for ADHD following pediatric cardiac surgery is significantly higher than the normal rate for children of the same age. Because this is a measureable long-term outcome, it can be used to evaluate methods for cerebral protection during surgery as well as the timing of surgical procedures to maximize cerebral oxygen levels.

This paper will review the pathophysiological basis for ADHD in this population, based on the similarities between neonatal cardiac surgical patients and pre-term infants. Both populations have an increased risk for ADHD and the etiology and pathological changes in pre-term infants have been widely investigated over the past 25 years. The rate of ADHD in this population is a window into the effects of these pathological changes on long-term outcomes.

Reducing the incidence of ADHD in the future in this population should be a primary goal in developing and assessing new cerebral protective strategies during cardiac surgery.