Approach to Continuous Sciatic Nerve Block for Orthopedic Procedures in Day Surgery With Two Different Techniques

Approach to Continuous Sciatic Nerve Block for Orthopedic Procedures in Day Surgery With Two Different Techniques

We will enroll patients submitted to feet elective orthopaedic surgery that require analgesia through continuous peripheral nerve block (CNPB) of the sciatic nerve. All catheters will be placed by anaesthesiologists experienced in ultrasound in prone positioning. The patients will be randomized in two groups with technique of sealed envelopes.

In the tibial -peroneal nerve (TPN) group we will position the catheter within the confluence of peroneal and tibial nerve.

In the tibial nerve (TN) group we will proceed , previous local anaesthesia, to insert a catheter medially to tibial branch of the sciatic nerve according to in plane approach.

We will analyze A: the difference in consumption of local anesthetic in the two different groups B: the difference of "insensate limb" in the post-operative home as described by Ilfeld(inability to perceive the sense of touch throughout the area of distribution of the sciatic nerve) C: rate of foot drop D: numeric rate scale (NRS) for pain assessment, rate of dislodgment of the catheters, patient satisfaction, need for intervention by the anesthesiologist after discharge.

Inclusion Criteria:

• Patients candidates for orthopedic surgery of the lower limb in unilateral day-surgery with surgical incision in the distribution of the sciatic nerve
• Patients according to American Society of Anesthesiologists scale (ASA) I-II
• Age greater than 18 years
• Informed Consent
• Presence of a "caretaker" for the night and the next day.

Exclusion Criteria:

• Contraindications to regional anesthesia
• Patients ASA III-IV
• Patients receiving therapy for chronic pain
• Patients with: renal failure, coagulopathy, liver failure, peripheral neuropathy
• Refusal by the patient