Nerve-stimulator guided paravertebral blockade vs. general anaesthesia for breast surgery:: a prospective randomized trial

Background and objective: Different anaesthetic techniques are used during breast surgery but are frequently associated with unsatisfactory postoperative analgesia. Paraverrebral nerve blockade has recently been proposed as a favourable alternative for this type of surgical procedure, providing excellent pain relief and a reduced incidence of postoperative nausea and vomiting. The aim of the present study was to compare the use of a nerve-stimulator guided paravertebral nerve blockade technique to regular general anaesthesia for breast surgery. Methods: Sixty patients were prospectively randomized to receive either paravertebral nerve blockade or general anaesthesia for breast surgery. The primary end-point of the study was to assess postoperative analgesia (visual analogue scale and supplemental opioid requirements); the incidence of postoperative nausea and vomiting and length of hospital stay were considered as secondary outcome measures. Results: Visual analogue scores both at rest and at movement, as well as the need for supplemental opioid administration during the first 3 days postoperatively, were significantly lower in patients handled with paravertebral nerve blockade compared to patients receiving general anaesthesia (P < 0.05). The number of patients free from nausea and vomiting after operation was significantly higher in the paravertebral nerve blockade group (93%) compared to the general anaesthesia group (67%) (P < 0.05). The use of paravertebral nerve blockade was also associated with a significantly shorter hospital stay (median I day) compared to general anaesthesia (2 days) (P < 0.01). Both the performance of the block and the intraoperative conditions was well accepted by the vast majority of patients treated by paravertebral nerve blockade (97%). Conclusion: The use of paravertebral nerve blockade was associated with improved postoperative pain relief, a reduced incidence of nausea and vomiting after operation and a shorter duration of hospital stay compared to general anaesthesia in patients undergoing breast surgery.