The development of the ERAS program includes elements of pre-operative, intraoperative and post-operative care. The main differences between the ERAS and TRAD programs are shown in Table 1. Additionally, in the ERAS group, 2 ml/kg of 5% GS was given orally every 3 h after 2 h of awakening from anaesthesia, and a residue-free diet was given on the first postoperative day, followed by a liquid diet on the second day, and gradually transitioning to a normal diet. In the TRAD group, patients were fasted for 3–5 days after surgery, starting with 5% GS and then gradually transitioning to a normal diet. If patient could tolerate oral feeding, the infusion was discontinued. For anaesthesia, dexmedetomidine continuous intravenous pumping combined with 0.25% ropivacaine injection 0.5 mg/kg local incision infiltration was used in the ERAS group. The FLACC pain rating scale was used for pain assessment at 2 h, 6 h, 12 h, 24 h postoperatively, respectively. Ibuprofen suppositories were used for analgesia when the FLACC pain score was ≥7.

Discharge criteria: fully tolerated orally; intravenous fluids stopped; good healing of surgical incisions; normal urination and defecation; no fever; no abdominal pain and none of the other complications.

After discharge, the nurse will follow up by telephone. If there was any discomfort such as fever or abdominal pain, the patient would be suggested to come back for examination. The follow-up time was 6 months.

SPSS version 26.00 was applied for statistical analysis. Normally distributed measurements were described by median and standard deviations, and independent samples t-test was used for comparison; Non-normally distributed data were described by median and quartiles, and Mann-Whitney u-test was used for comparison. Count data were compared using the χ² test or Fisher's exact probability method. All tests were two-tailed and P < 0.05 was considered a statistically significant difference.

The child’s anxiety and fear usually stems from unfamiliarity with the environment, whereas the parents’ anxiety often stems from a lack of knowledge about the disease and fear of surgery (14). Perioperative counseling provided by surgeons, anesthesiologists, and surgical ward nurses is very important, can provide relevant knowledge about MD, may alleviate children's and their parents’ psychological stress, and motivate participate in the perioperative care such as early mobilization and oral feeding. In our study, families were actively cooperating with the ERAS program. Parental satisfaction rate in the EARS group was 96%, which was higher than 90% in the TRAD group, although there was no statistical difference.

The changes of the fasting concept was the earliest measure proposed by ERAS. Long preoperative fasting can lead to dehydration, hypoglycemia, and anxiety in children (15, 16). According to the recommendations by the American society of anesthesiologists in 2017, clear liquids may be ingested for up to 2 h, breast milk for up to 4 h, infant formula and light meals or non-human milk may be ingested for up to 6 h before procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia (17). In this study, the ERAS group shortened the preoperative fasting time, relieved hunger, improved the comfort of patients, and alleviated anxiety among the children's families.

Pain is considered as the fifth vital sign (18).The pain regulation system of children is not as well developed as that of adults, and the level of stress response after surgery is approximately 3–5 times higher than that of adults (19). The wound pain after abdominal surgery restricts the respiratory movement, making it difficult to cough and expel airway secretions, pulmonary infections are prone to occur. At the same time, pain makes children cry and become irritable, delayis early postoperative mobilization time and affects wound healing. Single analgesic measure cannot achieve good analgesic effects, it is necessary to combine different analgesic drugs or different analgesic methods to make up for the inadequacy of a single analgesic drug or analgesic method (20, 21). The Guidelines for Perioperative Care in Elective Colorectal Surgery (2018) clearly states that postoperative analgesia should adopt a Multimodal Analgesia (MMA) Management (12).

MMA specifically recommends local analgesic techniques and believes that invasive local anesthesia through incisions is necessary for either open or laparoscopic surgery (22). Dexmedetomidine is a highly selective α2-adrenoreceptor agonist with sedative, analgesic, anxiolytic and sympatholytic without causing respiratory depression, it is commonly used in MMA (23). In this study, a multimodal analgesic regimen of local anesthesia combined with dexmedetomidine was used in the ERAS group, we found that the scores at 2 h, 6 h, 12 h, and 24 h after surgery in the ERAS group were lower than those in the TRAD group, indicating that the MMA patterns effectively alleviate postoperative pain in children and promote early mobilization after surgery.

Studies have shown that low temperature in the perioperative period can cause abnormal coagulation function, which can easily lead to the occurrence of complications such as surgical site infection, delayed wound healing, and cardiac arrhythmia (24), and the use of warm mattresses and heaters to maintain the child's core body temperature of no less than 36 °C can reduce intraoperative hemorrhage, shorten the operation time, and accelerate the recovery after the operation.

Research has found that minimally invasive laparoscopic surgery has lesser interference on the intestines than traditional open surgery, and the gastrointestinal function can be returned to normal in 1–2 days postoperatively. Nasogastric tube is not routinely used unless delayed gastric emptying occurs (12, 25). In addition, prolonged indwelling urinary tube not only increase the discomfort of children, but also increase the incidence of urinary tract infections. Postoperative prophylactic abdominal drainage in patients undergoing elective abdominal surgery does not reduce the incidence or severity of anastomotic leaks and other complications, therefore, centres with mature laparoscopic techniques may consider omitting abdominal drainage (26). In our study, nasogastric and urinary tubes were not routinely used in the ERAS group, nor did they place abdominal drainage tubes unless they had much exudation during surgery. No discomfort such as vomiting, abdominal distention, urinary retention, and no complications such as anastomotic leakage occurred after operation.

Almost all ERAS studies have measures related to early postoperative feeding. Regarding the choice of feeding time after intestinal surgery, most surgeons still follow the traditional principle of fasting for one week after surgery and then gradually starting eating. A study has found that fasting for more than 24 h after surgery leads to weakened muscle function and significantly increased insulin resistance in the body (27). In addition, prolonged fasting may impair immune function, affecting postoperative recovery and wound healing in children (28). Recent systematic review suggested that early enteral feeding within 24 h after abdominal surgery is safe and effective in children, can maintain intestinal nutrient absorption, also reduce the risk of any type of infection and the mean LOPS (29, 30). Studies have also shown that exercise can relieve pain and accelerate recovery of bowel function (31). Therefore, ERAS advocates starting enteral nutrition and postoperative mobilization as early as possible (32, 33). In our study, children in ERAS group were allowed to drink water on the first day after awakening from anaesthesia, and then gradually transitioned to a normal diet, and started getting out of bed on the first postoperative day. The time to first defecation and the time to first eating after surgery was advanced in the EARS group. It also shortened the postoperative intravenous infusion time and hospitalization time, reduced total treatment cost, and the incidence of postoperative complications did not increase.

Recovery of gastrointestinal function is an independent predictor of postoperative recovery. Excessive intraoperative fluid infusion not only leads to tissue oedema and increases cardiovascular and respiratory burdens, but also significantly affects the recovery of gastrointestinal function (34). The fundamental aim of fluid therapy is to maintain good tissue perfusion, both to avoid tissue hypoperfusion due to volume insufficiency and to avoid adverse effects from volume overload. During our surgery, the ERAS group used goal-directed fluid therapy and made appropriate adjustments based on urine output, intraoperative bleeding volume, and hemodynamic parameters (35). Once the patient can tolerate a normal diet after surgery, intravenous infusion were stopped in children. In this study, the time to first defecation was significantly shorter in the ERAS group, indicating that the ERAS programme resulted in a quicker recovery of gastrointestinal function.

However, this study has limitations such as single-centre design, small sample size and short follow-up time. Further expansion of the sample size and longer follow-up time are needed to investigate the applicability of this ERAS protocol to the paediatric population.