Primary objectives

1. To compare the onset and duration of sensory and motor block between levobupivacaine with dexmedetomidine and ropivacaine with dexmedetomidine

2. To compare post operative analgesia between levobupivacaine with dexmedetomidine and ropivacaine with dexmedetomidine

Secondary objectives

1. To compare the Ramsay sedation score between the two groups

2. To compare the hemodynamic parameters between two groups

Null hypothesis (H₀): There is no difference between the two drugs (levobupivacaine with dexmedetomidine and ropivacaine with dexmedetomidine) for onset of action, duration of action and postoperative analgesia.

Alternate hypothesis (H₁): Levobupivacaine with dexmedetomidine is better than ropivacaine with dexmedetomidine for onset of action, duration of action and postoperative analgesia.

1. American society of Anaesthesiology Grade (ASA) - I, II

2. Age between 18 years and 65 years

3. Elective upper limb surgery lasting more than 30 mins

1. Uncontrolled hypertension, diabetes mellitus, arrhythmias, 

2. Heart failure, renal failure, liver failure

3. Seizure disorder

4. Bleeding/ coagulation disorder

5. Pre-existing peripheral neuropathy

6. Known hypersensitivity to local anaesthetics.

7. BMI >30

8. Local skin infection

9. Pregnancy and lactating mothers

10. Bradycardia (heart rate <50 /min)

Patients will be randomized using simple lottery (sealed envelope) technique. Once patients received in preoperative area, patients will be divided into two groups; Group L and Group R based on envelope selected by them. Envelopes would contain drug details and dosage to be prepared by OT technicians. 

The drugs will be prepared as follows:

Group L: Levobupivacaine 0.5% (24 ml) with dexmedetomidine 50 mcg (1 ml)

Group R: Ropivacaine 0.5% (24 ml) with dexmedetomidine 50 mcg (1 ml)

Total volume of the drug will be 25ml for all patients.

Patient will be taken to the operation theatre; vitals will be monitored, and supraclavicular block performed under all aseptic precautions under ultrasound guidance by an anaesthesiologist who will be unaware of the drug composition. Once the study drug is delivered, following parameters will be assessed and noted.

1. Time of onset of sensory and motor block

2. Time when complete sensory and motor block is achieved

After achieving complete sensory and motor block patient is proceeded for surgery. Only successful block cases will be taken for study. Throughout intraoperative period vitals are monitored .Degree of sedation will be monitored at all intervals as that of vital parameters. On arrival in the postanaesthetic care unit, pain scoring will be assessed using Numeric Rating Scale (NRS) on movement of operated arm. NRS on movement will be assessed hourly following surgery till the request of first analgesic. Postoperative vitals will be assessed every hour till the regression of block. Any side effects such as nausea, vomiting, and sedation will be noted. Postoperative sedation score will be assessed hourly till the regression of block.