This study aims to evaluate the effects of minimal-flow sevoflurane compared with high-flow sevoflurane during maintenance of general anesthesia on postoperative emergence agitation in opioid-free pediatric infraumbilical surgeries. Patients will be randomly assigned to receive either opioid-free minimal-flow anesthesia combined with caudal block or opioid-free high-flow anesthesia combined with caudal block.

The primary outcome is emergence agitation assessed using the Pediatric Anesthesia Emergence Delirium (PAED) scale and the Watcha scale. Secondary outcomes include the incidence of postoperative nausea and vomiting and recovery characteristics. In addition, all patients will be followed up via telephone at 3 months postoperatively to assess the presence of persistent chronic or neuropathic pain at the surgical site.

The findings of this study may contribute to optimizing anesthesia strategies and improving postoperative outcomes in pediatric patients.

Emergence agitation (EA) is a common and clinically significant complication in pediatric patients following general anesthesia, particularly after the use of volatile anesthetic agents such as sevoflurane. The etiology of EA is multifactorial and may be associated with rapid emergence, postoperative pain, preoperative anxiety, and the use of opioids. Strategies aimed at reducing opioid consumption and optimizing anesthetic techniques may help improve postoperative recovery profiles in children.

Opioid-free anesthesia (OFA) has gained increasing attention as a multimodal approach that minimizes or eliminates intraoperative opioid use while maintaining adequate analgesia and hemodynamic stability. In addition, low-flow anesthesia techniques may contribute to improved respiratory conditions, better humidification, and more stable anesthetic depth, which could potentially influence emergence characteristics. However, the combined effect of opioid-free and low-flow anesthesia on emergence agitation in pediatric populations has not been sufficiently investigated.

In this prospective, randomized, single-blind study, pediatric patients undergoing infraumbilical surgery will be allocated to receive either opioid-free minimal-flow anesthesia combined with caudal epidural block or conventional anesthesia management. Emergence agitation will be assessed using the Pediatric Anesthesia Emergence Delirium (PAED) scale as the primary outcome, and the Watcha scale as a secondary assessment tool. Additional outcomes include postoperative pain scores, incidence of postoperative nausea and vomiting (PONV), and recovery parameters. This study aims to provide evidence on whether opioid-free minimal-flow anesthesia can improve postoperative behavioral outcomes and enhance recovery quality in pediatric patients.

Inclusion Criteria:

• Pediatric patients aged 2-10 years
• ASA physical status I-II
• Scheduled for elective infraumbilical surgery
• Planned to receive general anesthesia with caudal block
• Written informed consent obtained from parents or legal guardians

Exclusion Criteria:

• - Refusal of parental consent
• Known allergy to study drugs
• Neurological or developmental disorders
• Psychiatric disorders or use of psychoactive medications
• Chronic pain or regular analgesic use
• Contraindication to caudal block (infection at site, coagulopathy, anatomical abnormality)
• Significant cardiovascular, respiratory, hepatic, or renal disease
• Emergency surgery
• Signs of failed caudal epidural block, defined as a greater than 20% increase in heart rate or blood pressure in response to surgical stimulation, an increase in bispectral index (BIS) values, or the requirement for additional intravenous anesthetic agents.