Continuous Sciatic Nerve Block vs Epidural Analgesia in Lower Limb Amputation for Postoperative Pain

Bony landmarks and the space between the lower lumbar vertebrae are identified. Subsequently, infiltration of the skin and subcutaneous cellular tissue with local anesthetic (Lidocaine 2% without epinephrine) is performed at the site to be punctured. A 17G Tuohy needle is inserted 2-4 cm through the skin, then the mandrel is removed, the low-resistance syringe is connected, and the loss of resistance is checked using the air or liquid technique, depending on the preference of the anesthesiologist. . Appreciating the loss of resistance in the embolus, the mandrel is then withdrawn and the epidural catheter is advanced to leave it an additional 5 cm inside the epidural space.

The patient is placed in the prone or supine position with the limb to be blocked flexed at 90°. Using a high-frequency linear transducer and using sterile technique, the popliteal sciatic nerve is identified in an axial axis. A 17G Tuohy needle is inserted plane and medial. Saline solution (5 ml) is applied to open the perineural space. Adequate hydrodissection and donut sign in the nerve are observed..A perineural catheter is then advanced 5 cm beyond the tip of the needle. The catheter is fixed with stitches and a transparent sterile dressing is placed.