The Neonatal Brain and Opioids

The neonatal brain, and its response to pain, stress, and opioids, has been a topic of debate for decades. Most neonates are subject to painful procedures in hospital, which may have a profound adverse impact on neurodevelopmental and psychological outcomes. Repetitive painful stimuli alter perception and response to pain resulting in the “wind-up phenomenon.” The role of opiates is primarily to ameliorate adverse effects in the acute phase and mitigate the long-term sequelae of pain. Despite the benefit of analgesia, there are ongoing controversies that stem from evidence suggesting long-term adverse outcomes following the administration of opioids in neonates. Apoptosis seen in animals and human microglia cells has been attributed to morphine with a lasting impact in behavior, spatial recognition memory, and delayed response times. This chapter illustrates the response of a neonatal brain to opioids and pain, and addresses potential long-term consequences of pain and opioid therapy.