Comparisons of single-injection thoracic paravertebral block with ropivacaine and bupivacaine in breast cancer surgery: A prospective, randomized, double-blinded study

BACKGROUND: Regional anesthesia using paravertebral block has been suggested as an ideal adjunct to general anesthesia for modified radical mastectomy. Paravertebral block is an effective management of peri-operative pain for Modified radical mastectomy, however, there are no established guidelines regarding what is the most suitable strategy when varying drugs and dosages between different groups. AIM: To evaluate the effectiveness of paravertebral block comparing the most frequently employed drugs in this procedure (bupivacaine vs ropivacaine). STUDY DESIGN: Prospective randomized double blind study. METHODS: A total 70 ASA I and II adult female patients undergoing Modified radical mastectomy under paravertebral block followed by general anesthesia were randomly divided into two groups. The first group was administered 0.375% Ropivacaine in a dose 0.25 ml /kg in paravertebral block. The second group was administered bupivacaine 0.375% in dose 0.25 ml /kg in paravertebral block. Standard induction technique followed. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), were recorded pre block, post block 5 min, post block 10 min, at skin incision, post skin incision initially at 5 interval for first 15 min till one hour, and every 30 min till end of surgery. Post-operative visual analogue score for pain was recorded at 1 hr, 6 hr and 24 hr. STATISTICAL ANALYSIS: Chi-square test (Fisher's exact test) for qualitative variables. Independent sample t-test for quantitative data. RESULTS: Ropivacaine and Bupivacaine had no difference in intraoperative analgesia as shown by intraoperative hemodynamic parameters. Bupivacaine got better post-operative VAS scores (P < 0.05) in mean and after first, 6 h and 24 h.