Perfusion Index in Detection of Ulnar Nerve Sparing During Supraclavicular Block

"The linear transducer will be applied firmly above the clavicle in the coronal oblique plane the 22-gauge needle will be inserted at the lateral side of the ultrasound probe using In-plane approach. The needle will be advanced towards the target nerves inferior, lateral and superficial to subclavian artery respectively. Local anesthetic solution is injected between 20 to 25 ml.~Motor block will be assessed as follow Radial nerve = Push the arm by extending the forearm at the elbow against the resistance, musculocutaneous nerve = Resisting the pull of the forearm at the elbow, median nerve = Thumb and second digit pinch, ulnar nerve = Thumb and fifth digit pinch.~Sensory block will be assessed by using piece of ice in the distribution of median, ulnar, radial and musculocutaneous nerves."

Masimo reading of PI values will be recorded every minute (at both index and fifth digits) for 20 minutes then every 3 minutes for 30 minutes.