Serratus Anterior Plane Block with Methylene Blue and Ropivacaine for Analgesia in Prosthetic Breast Augmentation: A Randomized Controlled Trial.

[BACKGROUND] Pain is a prominent symptom following prosthetic breast augmentation by means of axillary incision, and persists throughout hospitalization. However, routine analgesia is not always effective for all patients. Duration of regional block with ropivacaine is also limited. The objective of this study was to evaluate whether the combination of methylene blue and ropivacaine by means of serratus anterior plane block provides superior long-lasting analgesia compared with ropivacaine alone in prosthetic breast augmentation.

[METHODS] This double-blind, single-center, randomized controlled trial enrolled 72 female patients, who were randomly and equally assigned to the control group, the ropivacaine group, and the ropivacaine plus methylene blue group during surgery. A standard postoperative analgesic regimen was administered to all patients. The visual analog scale was used to assess pain scores, which were observed and recorded at 6, 24, 48, and 72 hours postoperatively by 2 well-trained, independent investigators.

[RESULTS] No statistically significant differences were observed in age ( P = 0.200), body mass index ( P = 0.200), prosthesis brand ( P = 0.764), size ( P = 0.580), or type ( P = 0.260) among the 3 groups. The study demonstrated that serratus anterior plane block significantly improved postoperative pain management within 24 hours. Furthermore, the ropivacaine plus methylene blue group showed no advantages over the ropivacaine group at 6 hours postoperatively, whereas it had a better visual analog scale score than the ropivacaine group 24, 48, and 72 hours postoperatively, which were statistically significant differences ( P < 0.05).

[CONCLUSION] The analgesic effect of methylene blue and ropivacaine in serratus anterior plane block has a longer duration than ropivacaine alone in prosthetic breast augmentation.