Thoracic paravertebral block reduced the incidence of chronic postoperative pain for more than 1 year after breast cancer surgery

BACKGROUND: Thoracic paravertebral block (TPVB) is used to reduce pain after breast cancer surgery (BCS), but the pain-reduction effects more than 1 year after surgery are unclear. FINDINGS: Fifty-one patients underwent BCS at the Niigata City General Hospital from December 2009 through March 2010. To evaluate the long-term effects of TPVB in the reduction of chronic pain after BCS, we retrospectively reviewed the anesthesia charts and medical records of these patients and conducted telephone surveys regarding postoperative pain 13–17 months after surgery in 46 of these patients. Among the 46 patients enrolled in this study, 17 experienced chronic pain. There was a significant difference in the percentage of patients that received TPVB among those with and without chronic pain (patients with chronic pain 5/17 (29.4 %), patients without chronic pain 18/29 (62.1 %), p = 0.039). The pain score 3–6 h after surgery was significantly higher in the patients with chronic pain than without (p = 0.016). Bivariate logistic regression revealed that TPVB and pain score 3–6 h after surgery were independent predictive factors of chronic pain after BCS. CONCLUSIONS: These results indicate that TPVB has the potential to reduce chronic pain for more than 1 year after BCS.