This study will evaluate whether giving sedation before spinal anesthesia, when performed with ultrasound guidance, reduces the risk of developing back pain after surgery. Spinal anesthesia is commonly used but may cause discomfort or persistent back pain in some patients. By comparing standard techniques, ultrasound guidance, and sedation, we aim to find safer and more comfortable approaches for patients undergoing non-obstetric surgery.

Spinal anesthesia is widely used for abdominal and lower limb surgeries, yet a significant number of patients experience new back pain afterward, sometimes lasting for months. Contributing factors include needle size, multiple puncture attempts, and patient characteristics. Ultrasound guidance can improve accuracy and reduce complications, while pre-procedure sedation may lower anxiety and discomfort during the procedure.

This randomized controlled trial will include 180 adult patients scheduled for non-obstetric surgery. Participants will be divided into three groups:

Ultrasound-guided spinal anesthesia without sedation

Ultrasound-guided spinal anesthesia with sedation (midazolam)

Landmark-guided spinal anesthesia (control)

Sedation will be administered with midazolam before the spinal procedure in the sedation group. All patients will receive standardized anesthesia techniques. Pain will be assessed in the early postoperative period and during long-term follow-up (1, 3, and 6 months) using validated pain scales and questionnaires. Secondary outcomes include pain severity, number of needle attempts, procedure time, patient satisfaction, and complications such as headache or nausea.

This study will clarify whether combining ultrasound guidance with pre-procedure sedation can reduce both acute and chronic back pain after spinal anesthesia, aiming to improve patient safety, comfort, and satisfaction.

Inclusion Criteria

Adults aged 18-65 years ASA physical status I-II Body Mass Index (BMI) ≤ 35 kg/m² Scheduled for elective non-obstetric lower abdominal or lower limb surgery under spinal anesthesia Able to provide written informed consent

Exclusion Criteria

Contraindications to spinal anesthesia (e.g., coagulopathy, local infection at puncture site) Pre-existing chronic low back pain Chronic opioid use Known allergy or contraindication to study medications (bupivacaine, lidocaine, midazolam) Psychiatric or neurological disorders affecting pain perception or reporting Severe spinal deformities or history of previous spinal surgery Inability to comply with follow-up assessments