The aim of this study was to compare the efficacy of caudal block and sacral espb used as a postoperative analgesia method in urogenital pediatric surgery cases.

The parents of the patients who will undergo urogenital surgery will be included in the study after being informed and written consent is obtained. They will be randomised and divided into two groups. After general anaesthesia, sacral espb will be performed in the 1st group and caudal block will be performed in the 2nd group and postoperative pain will be evaluated with Face, Leg, Activity, Cry, Consolability (FLACC) score.

Inclusion Criteria:

• Patients aged 1-7 years undergoing paediatric urogenital surgery
• Patients in American Society of Anesthesiologist (ASA) class I-II

Exclusion Criteria:

• Patients whose parents do not give consent
• Patients with anatomical changes in the sacral region, previous surgery, scar and infection,
• Patients with known local anaesthetic allergy
• Patients for whom regional anaesthesia is contraindicated
• Known neurological or muscular disease

Randomisation using a closed envelope method based on computer-generated random numbers was to assign patients to two equal groups. Group 1 received midline US-guided sacral erector spinae plane block and Group 2 received caudal block. The experienced anesthetist who opened the envelope performed the block according to the group code and patients were followed postoperatively by an anesthetist blinded to which block was performed. Patients were also blinded as to which block was performed.