Chronic postsurgical pain in children: Current evidence and clinical perspectives

The chronification of acute pain following surgery is increasingly recognized, with a reported prevalence of 10%-63%, likely reflecting the increasing number of surgical interventions performed in the pediatric population. This pain is more severe after high-risk surgeries, such as spine surgery, hernia repair, and thoracotomy. Currently, the literature reports highly variable definitions of chronic postsurgical pain (CPSP) owing to a lack of objective diagnostic parameters. The International Association for the Study of Pain defines CPSP as "chronic pain that develops or increases in intensity after surgery or a tissue injury and persists beyond three months, without other causes". This pain can be localized to the surgical field or referred to the affected nerve domain. Similarly, the reported incidence of CPSP in children is largely from low-quality studies and varies between 20% and 50% in the studied population. Its neuropathic features are strongly associated with psychological consequences, functional limitations, and adverse long-term health outcomes. Potential risk factors in the pediatric population include psychosocial behaviors, pre-existing pain, postsurgical pain intensity, and the type of surgery performed. Proposed pathophysiological mechanisms include a pro-inflammatory state after surgery, leading to altered peripheral and central sensitization, genomic factors, epigenetic modifications, and altered brain physiology associated with chronic pain. Understanding the pathophysiology helps target interventions for pre-existing pain, surgery-related pain, anxiety, and opioid-induced hyperalgesia. Preoperative protocolized analgesic strategies, cognitive behavioral therapy, and acupuncture have been tried with varied success rates, although concrete data are lacking. The literature on regional analgesia is still limited in the pediatric population and represents a potential area for further research. Furthermore, rehabilitation interventions addressing postoperative trajectories with early referral to transitional pain clinics may offer promising avenues for improving outcomes. There is a significant knowledge gap, a scarcity of available data on CPSP, and difficulties in addressing pain in the pediatric population, underscoring the need for this review.