This will be a single-center randomized double blind placebo control clinical trial. In the cohort of patients undergoing hand surgery under axillary nerve block, participants are recruited from those who are willing to consent and participate in the study, and will be randomly 1:1 divided into intervention group and placebo group.

After the arrival to the operation room, monitoring including pulse oximetry, electrocardiogram, and noninvasive blood pressure was applied.

An 18 or 16-gauge IV cannula was inserted and Ringer's lactate infusion was started at a rate of 5 mL per kg per hour.

Antibioprophylaxis was systematically administered with 2 grams ofCefazolin 30 minutes before induction.

All patients were given an ultrasound-guided single-injection axillary plexus block by experienced anesthesiologists.

Sedation with 2 mg midazolam intravenously before block was administered.

In the group Dexamethasone (D), patients received axillary plexus block with a 30 ml of a 50/50 mixture of isobaric bupivacaine 0.5% and lidocaine 1%, containing 8 mg of dexamethasone.

In the group control (X), patients received a 30 mlof a 50/50 mixture of isobaric bupivacaine 0.5% and lidocaine 1% containing 2 ml saline solution.

For the axillary plexus block, patients were placed in a supine positionwith the arm in 90° of abduction and the forearm in flexion.A high frequency linear probe was placed on the transverse axis, over the axillary fold.The axillary artery, vein, and nerves surrounding the artery were visualized after scanning distally and proximally. The block needle (50 mm, 22G) was inserted in-plane from anterior to posterior, parallel to the ultrasound probe.It was advanced toward the musculocutaneous nerve (MCN) and local anesthetic was injected.Then, the needle was retracted and redirected deep relative to the axillary artery and local anesthetic was injectedaround the posterior aspect of the axillary artery and finallythe needle was retracted and redirected superficial to the axillary artery and local anesthetic was injected.

Before the surgical incision, the effectiveness of the sensory blockade of the axillary plexus was evaluated by a cold test in the different territories.

Post-operatively, all patients were put on systematic paracetamol 1 g every 6 hours, without exceeding 4 grams per day.

when the postoperative pain score (NRS) was >3/10, intravenous tramadol 100 mg was administered.

Inclusion Criteria:

• • Age between 18 and 75 years old.

  • Patients are current for hand surgery under axillary plexus block.
  • Patients classified ASA physical status I, II and III

Exclusion Criteria:

• - Contraindication to regional anesthesia.
• Patient's disapproval.
• Impaired cognition.
• Patients whose surgery must be done under general anesthesia (complex hand surgery or association of other)
• Allergy to paracetamol, dexamethasone or opioids