In recent years, as a part of multimodal analgesia, paravertebral blocks are replacing epidural analgesia due to the less side effects. Although the risk of pneumothorax is the most feared complication in paravertebral blocks, retrolaminar block (RLB) -which is a paravertebral block- significantly reduces this risk due to the anatomical technique of procedure. The investigators aim to investigate the effect of retrolaminar block with ultrasound- guided on perioperative analgesia for patients undergoing lumbar vertebra surgery.

Retrolaminar block will applie before general anesthesia induction when patients will be awake and under midazolam (0.03 mg/kg) sedation and standardized monitoring at the preoperative block area in sitting position using in-plane approach. After sterilising the skin, the investigators will perform block by using 7-18 MHz convex ultrasound probe ( Esaote My Lab 6 US Machine, Florance, Italy) and a 22-gauge, 100-mm Stimuplex needle (B. Braun, Germany). The investigators will pass in a sagittal plane from medial to lateral at the mid-lomber level, and identified the hyperechoic laminae, transverse processes, ribs and pleura.

The L3 laminae will be identified approximately lateral of the spinous process. The needle will insert in-plane, cephalad to caudad. After lamina contact and negative aspiration, 20 ml bupivacaine 0.25% will be injected at low pressure with intermittent negative aspiration on each side and spread of local anesthetic between laminae and paraspinous muscles will be seen without pain or paresthesia. Then 30 minutes later, the patient will be taken to the operating room.

After general anesthesia prosedure, the patients will evaluate whether they have pain throughout 24 hours after the operation. The pain scores will be evaluated with visuel analogue scale.

Inclusion Criteria:

1. 18-75 years old
2. ASA 1, 2, 3 patients
3. undergoing lumvar vertyebra surgery

Exclusion Criteria:

1. pregnant woman
2. child
3. patint wiht cognitive disfunction