Breast cancer is unfortunately the most common cancer in women, although survival rates have greatly increased in recent years. Breast surgery can be very aggressive and therefore highly painful, leading to high rates of acute postsurgical pain and chronic pain. In addition to general anesthesia (GA), ultrasound-guided regional anesthesia (RA) is sometimes performed to help reduce acute postoperative pain and consumption of opioids. Although effective, the main limitation of fascial plane blocks is that they require high volumes of local anesthetics, carrying the risk of local anesthetic systemic toxicity. In this article, we present the case of a 41-year-old woman, who refused GA and was successfully operated on for bilateral breast cancer, under a spontaneous breathing opioid-free sedation and ultrasound-guided RA, based on only 0.2% levobupivacaine with the addition of dexamethasone and dexmedetomidine as adjuvants. Despite this, postoperative analgesia lasted for more than 48 hours, and the patient did not require additional analgesia or opioids.