Comparison Between Bupivacaine and Ropivacaine in Patients Undergoing Forearm Surgeries Under Brachial Plexus Block

This prospective comparative randomized study was done to compare Bupivacaine and Ropivacaine in patients undergoing forearm surgeries under axillary brachial plexus block. The study compares the onset and duration of sensory block, onset and duration of motor block and duration of analgesia between these two drugs.

This is a prospective comparative randomized study to compare Bupivacaine and Ropivacaine in patients undergoing forearm surgeries under axillary brachial plexus block. A sample size of 100 was considered who are meeting the inclusion and exclusion criteria were selected, and divided into two groups of 50 each using computer-generated randomization and allocation concealment was done using sealed sequentially numbered containers opaque envelope technique (SNOSE). One group will receive Bupivacaine and the other Ropivacaine. Patients were blind to the study. In the Bupivacaine group, 30 ml of 0.5% bupivacaine was injected equally divided and injected in four nerves (musculocutaneous, median, radial and ulnar nerves). In the Ropivacaine group, 30 ml of a solution containing 0.5% ropivacaine was equally divided and injected in the four nerves. Sensory block was tested with a 22-gauge hypodermic needle by using the pinprick test and compared with the contralateral hand. Sensory block was graded as Grade 0: Sharp pin felt, Grade 1: Analgesia, dull sensation felt and Grade 2: Anaesthesia, no sensation felt. Motor function was assessed as per the modified Bromage scale. 0: Able to raise the extended arm to 90 degrees for a full 2 sec, 1: Able to flex the elbow and move the fingers but unable to raise the extended arm, 2: Unable to flex the elbow but able to move the fingers and 3: Unable to move the arm, elbow or fingers. The onset of sensory blockade was assessed by the time from the completion of injection of the study drug till the loss of pinprick sensation. It was assessed every minute. The onset of motor blockade was assessed when there was Grade 1 motor blockade. It was assessed every minute. Duration of sensory blockade was assessed by the time between onset of sensory blockade and return of dull sensation to pinprick. .It was assessed every 15 minutes. Duration of motor blockade was assessed by the time between onset of motor blockade and time at which patients could first move their fingers. It was assessed every 15minutes. Duration of analgesia is the time interval between the onset of sensory block and the patient's first analgesic request. The rescue analgesia in the form of inj. Diclofenac sodium (1.5 mg/kg) intramuscularly was given. Block was considered to have failed when sensory anaesthesia was not achieved within 30 min. General anaesthesia was given subsequently to these patients and was excluded from the study. Again, a patient showing an allergic reaction to the intervention were also withdrawn from the study.

Statistical Analysis - Normally distributed quantitative data were presented as mean ± SD, whereas data not normally distributed were presented as median (IQR). While comparing quantitative data between the two groups, for normally distributed quantitative data, Independent student t-test was used, on the other hand, Mann-Whitney test was used. For comparing qualitative variable chi-square or Fischer exact test was applied as appropriate. In case of repeated measure data, mixed effect ANOVA was used. For all test P value of \< 0.05 was considered as significant and P-value \< 0.001 was considered as highly significant. SPSS version 21 (IBM, Newyork) was used for data analysis.

Eligibility Criteria:
Inclusion Criteria:

- Patients with ASA classes I and II who gave consent and were candidates for elective forearm surgeries.

Exclusion Criteria:

1. Any allergic reactions to ropivacaine, bupivacaine and lignocaine.
2. All patients with hypertension, cardiac, hepatic or renal diseases.
3. Pregnant women, drug abusers and psychiatric patients.
4. Patient who had an anatomical or vascular abnormality in the upper extremity.
5. Bleeding diathesis.
6. Local infection of the axilla.
7. Patient refusal.