Comparative Study Between Ketamine-Bupivacaine Versus Bupivacaine With Intravenous Ketamine Infusion In Supraclavicular Brachial Plexus Block During Upper limb Surgeries The techniques of regional anesthesia have become very popular as they provide several advantages in comparison with general anesthesia and systemic analgesia.

They provide perfect pain control, decreased complications and reduced post-anesthesia care unit stay.

Regional anesthesia provides more patient safety and better outcomes, which leads to the fact that ultrasound-guided regional anesthesia became more popular.

Ultrasound provides clinicians with real-time images which are useful for better identification of the anatomical structures, safe needle placement and adequate local anesthetic spread.

Brachial plexus blocks are commonly achieved via an interscalene, supraclavicular, infraclavicular or axillary approach.

The supraclavicular level is an ideal site to achieve anesthesia of the entire upper extremity just distal to the shoulder as the plexus remains relatively tightly packed at this level, resulting in a rapid and high-quality block. For this reason, the supraclavicular block is often called the ''spinal of the arm'' Using the local anesthetics alone for supraclavicular brachial plexus block provide good operative conditions but have the disadvantage of shorter duration of postoperative analgesia. Various adjuvants such as opioids, dexmedetomidine, dexamethasone, midazolam, ketamine, etc., were added to local anesthetics in brachial plexus block to achieve quick and prolonged block.

Ketamine is a noncompetitive antagonist of the N-methyl-D aspartate receptor(NMDAR).

It is used as a premedication, and for sedation, induction and maintenance of general anesthesia.

Local anesthetic and analgesic properties have been reported for ketamine. Intravenous administration of low-dose ketamine decreases postoperative opioid use and improves analgesia.

Ketamine has been added to bupivacaine to prolong the duration of regional anesthesia and postoperative analgesia.

Inclusion Criteria:

• Age 18 to 75 years.
• ASA physical status I-II, scheduled.
• Patients of either sex.
• Unilateral elective upper limb surgeries undergoing under ultrasound guided supraclavicular brachial plexus block.

Exclusion Criteria:

• Patient refusal.
• Patients with peripheral neuropathy of the upper limb.
• Infection at the injection site.
• Uncontrolled diabetes, epilepsy, obstructive pulmonary disease and neuromuscular disease.
• Altered mental status.
• Hypersensitivity to bupivacaine and ketamine.
• Patients with coagulopathy.