Anesthesia was maintained with sevoflurane (Inhalation Sevoflurane, Brand: Kaiteli, Specification: 120 mL, Approval Number: National Drug Approval H20070172, Manufacturer: Shanghai Hengrui Pharmaceutical) combined with continuous intravenous infusion of remifentanil.

Anesthesia was maintained with remifentanil combined with continuous intravenous infusion of propofol at a maintenance dose of 0.5 mg/(kg·h).

Patients fasted for 6 hours and abstained from clear fluids for 3 hours preoperatively. Upon entering the operating room, oxygen was administered via an appropriately sized face mask at a flow rate of 6-8 L/min. Anesthesia was induced by sequential intravenous injection of remimazolam, sufentanil, and rocuronium. A laryngeal mask was inserted after the disappearance of the eyelash reflex. Anesthesia was maintained with sevoflurane (Inhalation Sevoflurane, Brand: Kaiteli, Specification: 120 mL, Approval Number: National Drug Approval H20070172, Manufacturer: Shanghai Hengrui Pharmaceutical) combined with continuous intravenous infusion of remifentanil. During surgery, vital signs and body movement responses were closely monitored, and the inhaled concentration of sevoflurane was adjusted as needed (maintained at 1%-3%). Administration of anesthetics was discontinued 5 minutes before the end of surgery.

The levels of inflammatory factors IL-1β, IL-6, and TNF-α in pediatric patients will be measured using ELISA before surgery, 30 minutes during surgery, and one day after surgery. Simultaneously, the levels of neurotrophic factors BDNF and GDNF will be detected using ELISA. The RASS scale was employed to assess the level of emergence agitation in the children. A t-test will be used to compare whether the inflammatory factor levels between the two groups were correlated with the occurrence of emergence agitation, to determine whether the pre- and postoperative changes in neurotrophic factors are statistically significant, and to evaluate whether these changes is correlated with the incidence of emergence agitation.

The levels of inflammatory factors IL-1β, IL-6, and TNF-α in pediatric patients will be measured using ELISA before surgery, 30 minutes during surgery, and one day after surgery. Simultaneously, the levels of neurotrophic factors BDNF and GDNF will be detected using ELISA. The Wechsler Scale II will be employed to assess the learning and memory abilities of the children at five years of age. A t-test was used to compare whether the inflammatory factor levels between the two groups will be correlated with the development of long-term learning and memory function, and to evaluate whether changes in these levels were associated with the occurrence of long-term learning and memory function.

We will categorize the surgeries into upper abdominal, lower abdominal, and limb procedures based on human anatomical structure. Correlation analysis will performe between these surgical categories and the levels of inflammatory factors and neurotrophic factors measured by ELISA. This analysis aim to evaluate whether the type of surgery will correlate with changes in inflammatory factor levels, as well as to examine the association between surgical categories and the occurrence of postoperative delirium.