Effect of Intraoperative Ankle Nerve Blocks on Postoperative Discharge in Patients Undergoing Orthopaedic Foot Surgery

After written informed consent obtained from patients, patients will be randomly assigned to placebo group (Group I) and block group (group II) using sealed envelope method. IV venous catheter will be inserted and saline or Ringer's Lactate solution will be infused to patients for prehydration.0.1-0.5 mg/kg midazolam will be given for premedication. After arriving into OR, the patients will be monitored with ECG, pulse oximetry and noninvasive blood pressure. Anesthesia will be induced using 2-2,5 mg/kg propofol, 1-2 mcg/kg fentanyl, 10 mg-20 mg rocuronium, and a proper size laryngeal mask airway (LMA) will be placed to secure the airway. The lungs will be ventilated with a mixture of 50% air + 50% oxygen. Propofol and remifentanil based total intravenous anesthesia (TIVA) technique will be used for the maintenance of anesthesia. Tenoxicam 20 mg will be used for preemptive analgesia, cefazolin 25 mg/kg for antibiotic prophylaxis, ranitidine 50 mg for gastric protection, and metoclopramide 10 mg for postoperative nausea and vomiting. Acetaminophen 10-15 mg/kg IV will be given for postoperative analgesia at the time of wound closure.

At the end of the operation, an ankle nerve block will be performed in group II patient using a mixture of 2%lidocaine and 10 ml of bupivacaine and the same amount placebo in group I (placebo group) under the guidance of peripheral nerve stimulator. The anesthesia will be discontinued and LMA will be removed. The patients will be transferred from postoperative care unit to the ward after they were eligible for discharge according to modified Aldrete scoring system.

Postoperative analgesia will be evaluated by a study member who is blinded to study groups using visual analog scale (VAS). Acetaminophen 1000 mg p.o. were given at 8 hours intervals and an intravenous patient-controlled analgesia containing 3 mg/ml of tramadol will be used for postoperative pain therapy. Pethidine 0.5 mg/kg IV will be used for rescue analgesic if VAS score is greater than 3.

The motor block will be evaluated using Bromage scale, sensorial block with pin-prick test. The duration of motor and sensorial block, postoperative VAS scores, the time to the first analgesic requirement, total analgesic consumption and vital parameters will be recorded. Patient's satisfaction will be evaluated using 3 point scale between the scores 0 and 2. 0= poor 1= fair 2=satisfied Postoperative discharge times will be recorded.

Inclusion criteria

• Patient's acceptance,
• American Society of Anesthesiologists physical status I-III
• elective orthopedic foot surgery
• general anesthesia

Exclusion criteria

• Pregnancy
• history of chronic pain therapy
• hypersensitivity to study drugs
• allergy to study drugs
• blood coagulation disorder
• anticoagulant use