Background
Thoracic paravertebral block (TPVB) is an effective intraoperative and postoperative technique for surgical anaesthesia and analgesia for breast surgery. It offers a long-lasting effective analgesia without increases in side effects, with a significant decrease in anaesthetic and analgesic consumption, and with a high degree of patient satisfaction and shorter recovery time. In this study, TPVB was done by using a nerve stimulator to measure the depth of needle insertion by eliciting intercostal muscle contraction, and a catheter was introduced preoperatively to allow for repeated injections and to maintain analgesia postoperatively.
Methods
Two groups of patients undergoing unilateral cancer breast surgery (each 20 patients) were randomly assigned to the study; a study group (PVB) and a control (C) group. The study started by preoperative application of an epidural catheter by using the nerve stimulator at the fourth thoracic paravertebral space in the study group and injection of local anaesthetic started preoperatively. General anaesthesia was started for the two groups. Total intraoperative fentanyl and postoperative morphine consumption, and pain intensity at rest and with arm movement were recorded, together with recording of any undesirable side effects for 24 h.
Results
There were statistically highly significant decreases in intraoperative fentanyl consumption and postoperative morphine consumption in the PVB group than the C group. There were statistically significant decreases in the VAS in the PVB group than the C group both at rest and with shoulder movement. The incidence of adverse events was very low in both groups.
Conclusion
Continuous TPVB provides effective pain relief, significant opioid sparing, and also less painful restricted movement of the shoulder, with few side effects after breast cancer surgery. Thoracic paravertebral somatic nerve block may be an alternative to general anaesthesia for major unilateral breast surgery with heavy sedation or to be combined with light general anaesthesia.