Persistent Post-discharge Pain After Breast Surgery With Paravertebral Block: Incidence, Characteristics and Consequences

Breast cancer is the most frequent cancer in women, with an incidence of more than one million new cases per year. In the majority of cases surgery is part of the treatment and prognosis has progressively improved during last years. Attention is thus being increasingly focusing on these patients' quality of life and chronic postsurgical pain, defined as pain in the area of surgery lasting beyond 3 month from the operation, has emerged as a frequent long-term complication, with prevalence up to 60%. This often-disabling condition has been shown to significantly affect cancer survivors' quality of life and to have a heavy economic impact on the healthcare system.

Many potential risk factors have been proposed for the development of chronic post-breast surgery pain. A Cochrane systematic review has addressed the role of regional anesthesia in preventing the development of chronic postoperative pain, suggesting that "paravertebral block may reduce the pain after breast cancer surgery in about one out every five women treated", these results being however weakened by the often poor quality and inadequate power of the studies available. Many predictors of chronic postoperative pain have been identified, one of them being a poorly treated acute pain; in this perspective, regional anesthesia could possibly play a role in preventing nervous system remodeling with resultant hyperalgesia, allodynia and sustained wound pain.

Even if chronic postoperative pain has been progressively recognized as an issue after breast cancer surgery, its link to poorly treated acute postoperative pain and post-discharge pain (PDP) has been poorly investigated. Single shot paravertebral block is an effective technique to provide both anesthesia and good analgesia after breast surgery, but its benefits duration is still debated.