Thoracic epidural analgesia and anesthesia are effective in improving the quality of intraoperative and postoperative pain relief during thoracic and abdominal surgical procedures. Conventional epidural techniques have significant limitations. Due to the anatomic characteristics of the thoracic versus the lumbar intervertebral spaces, the insertion requires a more technically challenging paramedian approach. The safety and feasibility of bedside ultrasonography for the lumbar spine has already been established and it proves to be a valuable tool for neuraxial anesthesia in obstetric anesthesia

• The feasibility and the reliability of US imaging for the thoracic spine has been proven by comparing the findings of ultrasound scans to MRI measurements, which is the standard imaging technique for the depiction of the spine. Pre-puncture US assessment may contribute to the safety and efficacy of the thoracic epidural technique. The purpose of this study is to compare the ultrasound-guided thoracic epidural insertion technique with the conventional anatomic landmarking technique of contacting bone and walking-off the lamina

Inclusion Criteria:

• Age > 18 years old.
• Elective major abdominal or thoracic surgery requiring thoracic epidural anesthesia/analgesia.
• Consent to participate and signed consent form.

Exclusion Criteria:

• Contraindication to epidural anesthesia.
• Marked spinal deformities or a history of spinal instrumentation
• Emergency surgery.
• Inability to communicate in English.
• BMI>35 kgm-2