Liposomal-encased bupivacaine (LEB) is a good, cost-effective medical choice for pain control after breast surgery.
Valerie Lemaine, MD, MPH, an assistant professor of plastic surgery and the vice chair for research at Mayo Clinic College of Medicine, Rochester, Minn., reviewed her experience at the 32nd Annual Miami Breast Cancer Conference. She noted that the drug has proved safe, decreased opioid requirements and reduced costs for patients having breast surgery at Mayo Clinic.
LEB is a recently approved formulation of bupivacaine loaded in multivesicular liposomes, which allows slow release from the liposome and increases the duration of local anesthetic action (Figure). LEB is FDA-approved for postoperative analgesia when given as a single-dose surgical site injection. In breast surgery, LEB has been used in patients after mastectomy, lumpectomy, and autologous and implant-based reconstruction.
As background, Dr. Lemaine emphasized the frequency at which postsurgical pain and chronic pain are inadequately managed. Among almost 500,000 breast surgical procedures performed annually in the United States, as many as half may result in chronic postoperative pain of the scar, breast, chest wall, shoulder or arm as a result of nerve injury, inflammation or inadequate management of acute pain, she said.
“In my opinion, this is a significant problem for these women, especially with breast cancer treatments available today that positively impact survival. Now that women live longer after diagnosis, quality of life becomes more important and living pain-free is a key component,” she said.
Plasma levels of LEB can persist up to 96 hours, although in Dr. Lemaine’s experience, 72 hours is more likely. The pain relief provided by LEB has best been observed in patients who undergo microsurgical breast reconstruction and are typically hospitalized for three to four days.
“You can really see a difference around day 3, when patients start taking more oral medications for pain control because the liposomal bupivacaine is starting to wear off,” she said.
Dr. Lemaine said she dilutes the drug with preservative-free normal saline, up to a total of 260 cc, but also occasionally injects it undiluted, depending on the situation. LEB must be injected within four hours of preparation, a characteristic she makes sure to communicate to the surgical team.
Showing a video of how she uses LEB in tissue expander breast reconstruction, she noted, “I perform a field block and inject the entire surgical site following the mastectomy. The injection is intramuscular and sometimes also subcutaneous. I adjust the dilution and, for example, in very large-breasted women, I may increase my dilution. I make these decisions intraoperatively, on a case-by-case basis, based on body habitus and size of the surgical site.”
When mastectomy skin flaps are sufficiently thick, she may inject subcutaneously, addressing the subclavicular area and lateral subcutaneous tissue before inserting tissue expanders. Although reports suggest that other anesthetic agents can be used safely in conjunction with liposomal bupivacaine, Dr. Lemaine has not personally done so.
LEB Versus Paravertebral Block
Dr. Lemaine and her colleagues recently compared patients who had LEB or paravertebral block in conjunction with mastectomy and immediate breast reconstruction using tissue expanders. “Regional block is our standard of care postmastectomy but, having a good experience with LEB in microsurgical breast reconstruction, we thought LEB could be useful when we used tissue expanders.”
In this retrospective (and unpublished) evaluation, LEB offered a number of advantages, she said. Patients receiving LEB required less opioids in the recovery room, had a longer time-to-first opioid use, required fewer postoperative antiemetics on day 1 and had lower mean pain scores on postoperative day 0.
LEB was also less time consuming, she added. “Paravertebral blocks take time—adding about 45 minutes to a procedure at my institution—and this has been a source of frustration for our plastic surgeons.” Paravertebral blocks also carry a small risk for pneumothorax, she added.
“In my two years of experience with LEB,” Dr. Lemaine concluded, “I have found this to be safe, to make a difference to my patients and to be cost saving. I do think there’s a learning curve, so surgeons should not get discouraged. Good communication with anesthesiology and with postoperative nursing is key to providing the best analgesia, and to improving outcomes overall.”
Basavana Goudra, MD, of the University of Pennsylvania, Philadelphia, commented on the presentation in an interview. He noted that LEB is used in various other procedures, such as hemorrhoidectomy, bunionectomy, colectomy and total knee arthroplasty. It has proved beneficial in placebo-controlled studies; however, a statistically significant advantage has not been shown when compared with bupivacaine with epinephrine, he said.
“The nature of release and later metabolism might give LEB a safety advantage. A reduction in the total dose of bupivacaine needed to achieve a clinical benefit is another reported benefit,” Dr. Goudra said.
In research settings, LEB is used both as epidural and perineural injections, which can produce prolonged sensory blockade, an important feature. Currently, however, it is not approved by the FDA for routes other than wound infiltration, he added.