Congenital heart disease (CHD) refers to cardiovascular malformations caused by abnormal development of the cardiovascular system during the fetal period, developmental disorders, or the non-degeneration of tissues that should be degraded after birth (Zhao et al., 2024). At present, the global incidence rate of CHD is approximately 16‰ (Yang et al., 2025). With advancements in surgical medical techniques and intensive care, the mortality rate of CHD has decreased significantly (GBD 2017 Congenital Heart Disease Collaborators., 2020). Most children with CHD can live up to adolescence or even middle age with surgical treatment. Anatomical and physiological complications are no longer the sole focus of medical attention; instead, mental health and long-term quality of life are gradually becoming areas of concern among health care teams (Dellborg, 2024). Experts note that postoperative delirium (POD) represents the third major challenge for children with CHD surviving into adulthood, following neurological psychological and emotional damage (Nelson et al., 2022).

Delirium is characterized by an acute disturbance in attention and awareness that develops over a short period and fluctuates in severity throughout the day, accompanied by additional disturbances in cognition, such as memory, orientation, language, visuospatial ability, or perception. These disturbances cannot be explained by a pre-existing or evolving neurocognitive disorder. Furthermore, evidence from the patient's history, physical examination, or laboratory findings must demonstrate that these disturbances are a direct physiological consequence of one or more underlying etiologies (American Psychiatric Association, 2013). POD refers to the disturbance of attention and consciousness that occurs within 7 days after surgery or prior to discharge (Evered et al., 2018). International studies have pointed out that the incidence of POD in children with CHD is significantly higher than in other surgical procedures (Meyburg et al., 2017), with an incidence of approximately 9.8%–68.5% (Köditz et al., 2023; Yang et al., 2021). In the short term, POD can lead to an extension of time in the intensive care unit (ICU), a longer hospital stay, and an increase in mortality (van den Boogaard et al., 2012). In the long term, POD can have a negative and continuous impact on the neuropsychological, mental, emotional, cognitive, and activity abilities in children with CHD, and can affect the quality of life in adulthood of these children (Huang et al., 2023; Leroy & Schieveld, 2017).

In recent years, only one systematic review conducted by Fu et al. (2024) has summarized the etiological factors for POD in children with CHD. Not only did this review focus on children undergoing surgery, but it also included children who underwent cardiac catheterization. The study included in the meta-analysis was based solely on two original studies, which limited its ability to explain the high incidence of POD in congenital heart surgery. Furthermore, its inclusion period of this study ended in November 2023, and since then, multiple high-quality studies on the influencing factors of POD in CHD have been published. Based on this, it is necessary to further ynthesize and refine the factors influencing POD in congenital heart surgery.

The 2022 U.S. guidelines (Smith et al., 2022) state that non-pharmacologic management can effectively prevent the incidence of POD and shorten its duration, thereby improving its prognosis. The early identification at a high risk of POD enables nurses to initiate and implement targeted non-pharmacological management promptly. However, for children, especially young children (Traube et al., 2014), cognitive development issues prevent them from providing subjective statements, making the assessment of delirium in children extremely challenging. In recent years, global clinical studies have constructed predictive models based on high-risk factors to help identify delirium levels in children at high risk of CHD after surgery. However, due to the lack of targeted analysis of influencing factors, these predictive models have demonstrated poor predictive performance (Lin et al., 2024; Mao et al., 2024), limiting their clinical use and promotion. Therefore, the purpose of this study is to further sort out and clarify the key risk factors that affect delirium after CHD surgery by synthesizing the existing literature, laying the foundation for further developing more robust prediction models and implementing effective interventions in the future.