Randomized, parallel-group, assessor-blinded clinical trial at Tanta University Hospitals comparing ultrasound-guided sacral erector spinae plane block (sESPB) versus ultrasound-guided caudal epidural block for postoperative analgesia in male children (1-5 years) undergoing hypospadias repair. Seventy participants will be randomized 1:1 to receive sESPB or caudal block with 0.25% bupivacaine (0.5-1 mL/kg; maximum 20 mL) after induction of general anesthesia. The primary outcome is pain over the first 24 hours, assessed using the FLACC scale at prespecified time points. Secondary outcomes include total opioid consumption, time to first rescue analgesia, postoperative nausea and vomiting, parent/guardian satisfaction, hemodynamic trends, and predefined adverse effects (e.g., motor weakness, urinary retention, respiratory depression, hematoma, infection at injection site). Perioperative care is standardized; rescue pethidine is administered when FLACC ≥4. The trial evaluates whether sESPB provides superior or comparable analgesia with fewer adverse effects than caudal block.

Randomized, parallel-group, assessor-blinded clinical trial at Tanta University Hospitals comparing ultrasound-guided sacral erector spinae plane block (sESPB) versus ultrasound-guided caudal epidural block for postoperative analgesia in male children (1-5 years) undergoing hypospadias repair. Seventy participants will be randomized 1:1 to receive sESPB or caudal block with 0.25% bupivacaine (0.5-1 mL/kg; maximum 20 mL) after induction of general anesthesia. The primary outcome is pain over the first 24 hours, assessed using the FLACC scale at prespecified time points. Secondary outcomes include total opioid consumption, time to first rescue analgesia, postoperative nausea and vomiting, parent/guardian satisfaction, hemodynamic trends, and predefined adverse effects (e.g., motor weakness, urinary retention, respiratory depression, hematoma, infection at injection site). Perioperative care is standardized; rescue pethidine is administered when FLACC ≥4. The trial evaluates whether sESPB provides superior or comparable analgesia with fewer adverse effects than caudal block.

Inclusion Criteria

• Male children aged 1-5 years
• ASA physical status I-II
• Scheduled for elective hypospadias repair under general anesthesia
• Parent or legal guardian provides written informed consent
• Able to complete postoperative assessments through 24 hours after surgery Exclusion Criteria
• Parent/guardian refusal of participation
• Coagulopathy or current anticoagulant therapy
• Infection at the intended injection site (sacral/caudal region) or systemic infection
• Allergy/hypersensitivity to amide local anesthetics (e.g., bupivacaine) or study medications
• Neurologic or spinal disorders or congenital sacral anomalies affecting block safety
• Significant hepatic, renal, or cardiac disease
• Any other condition that, in the investigator's judgment, contraindicates caudal block or sacral ESPB or could interfere with safe participation

Male only. Enrollment is limited to pediatric patients with male genitalia (sex assigned male at birth) undergoing hypospadias repair. Rationale: hypospadias is a congenital condition of the penis and occurs in males; therefore, females and other genders are not eligible."

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

After the end of study for one year.

The data will be available upon a reasonable request from the corresponding author