Single-injection paravertebral block compared to general anaesthesia in breast surgery.

Background: Breast surgery is frequently associated with post-operative nausea, vomiting, pain and painful restricted movement. Paravertebral block may be an alternative to general anaesthesia for this type of surgery. We studied the single-injection paravertebral block at the level of T4 and report a comparison of single-injection paravertebral block to general anaesthesia for breast surgery.
Methods: After written informed consent was obtained, 86 patients were enrolled in this prospective study. Forty-four women were randomly allocated to receive a single-injection paravertebral block at the level of T4, while 42 women received general anaesthesia. The surgical procedures varied from lumpectomy (wide local excision of a tumour) to modified radical mastectomy with axillary dissection. The block was performed according to the guidelines described by Eason and Wyatt using 0.3 ml x kg(-1) (maximum dose 150 mg) of bupivacaine 0.5%. The skin and the underlying tissues were infiltrated with local anaesthetic solution two fingers (about 3 cm) from the anatomical midline and level with the cephalad end of the vertebral spine.
Results: Time for performance of blocks lasted from 4 to 9 min. Recovery from anaesthesia or sedation was shortened, while postoperative pain scores (VAS), the incidence of vomiting and the requirement for analgesics were lower in the paravertebral group. Less painful restricted movement was observed in the paravertebral block group. Paravertebral block was inadequate in 6.8% of patients. Epidural spread with paraparaesis and Horner triad was assumed in one patient.
Conclusion: Single-injection paravertebral block at the level of T4 represents a suitable alternative to general anaesthesia in women undergoing breast surgery.