The Use of Single-Injection Thoracic Paravertebral Block in Breast Cancer Surgeries in Our Asian Population: The Singapore General Hospital Experience

Abstract

Background: This series of cases describe the experience of using the single-injection thoracic paravertebral block of ropivacaine 1% to provide analgesia in breast cancer surgery in Asian patients within the Singapore General Hospital. Cases: Over these eight years, we documented 32 cases scheduled for elective breast cancer surgery with axillary dissection. These patients received 20 ml ropivacaine 1% with adrenaline (5 ug/ml) injected into the paravertebral space prior to surgery. All patients received a standardised regime of general anaesthesia, using fentanyl (if intra-operative supplemental analgesia was required). Patient-controlled analgesia (PCA) of morphine was used for post-operative analgesia. Assessments included peri-operative analgesic requirement, pain score, and shoulder movement limitation, incidence of nausea or vomiting, and adverse effects of the block. Observations: Parathesia using the loss of pinprick sensation was elicited in all patients after the institution of the block. A median of seven (range 4–11) dermatomes were recorded in this series. Seventy-five percent of the patients underwent surgery without supplemental analgesia. In the immediate post-operative period, 87.5% of patients reported none-mild pain. Over 90% responded with none-mild pain in the 24-hour post-operative period. No local anaesthetic toxicity or severe adverse effects of paravertebral block was observed. Conclusion: The single-injection of ropivacaine 1% into the thoracic paravertebral space is a useful alternate analgesia strategy for breast cancer surgery in our Asian population.