What is the Role of Liposomal Bupivacaine in TSA?

Results of a prospective randomized trial were recently reported in JSES International, addressing a long-standing question about the opioid-sparing effect of liposomal bupivacaine (LB) for interscalene block (ISB) in total shoulder arthroplasty (TSA).

Among patients assigned to receive either bupivacaine control or bupivacaine plus LB for an ISB, there was a statistically significant but not clinically meaningful reduction in opioid use over the first 72 hours after TSA.

The study was led by Mandeep S. Virk, MD, associate professor of orthopedic surgery and chief of the Division of Shoulder and Elbow Surgery at NYU Langone Health.

“Both clinical benefit and cost-effectiveness are important factors in the current healthcare environment,” says Dr. Virk. “It’s hard to justify the use of LB when it’s 150 to 180 times more expensive than the nonliposomal version, yet only results in a reduction of about two or three opioid pills postoperatively.”

Achieving Adequate Postoperative Pain Control

While LB was approved by the FDA in 2018 for use in an ISB in shoulder surgery, evidence for its benefit in TSA remains controversial, Dr. Virk explains, with some studies reporting that LB shows no clinically significant benefit in improving postoperative analgesia when compared to bupivacaine.

“Despite a theoretical advantage of prolonged analgesia with LB, there’s been mixed results reported in the literature about its use in TSA,” explains Dr. Virk. LB is also used in other shoulder procedures, such as rotator cuff repair, but findings in those settings are similarly mixed.

Minimizing postoperative pain and reducing side effects from general anesthesia and opioids is important, he notes, especially to promote value-based healthcare. But given its higher cost compared with nonliposomal bupivacaine, LB warrants further study to understand its potential benefits.

No Clinically Meaningful Opioid-Sparing Effect

The trial was conducted at the NYU Langone Orthopedic Center. Of the 184 patients who were randomized, 150 were included in the final analysis, with 78 and 72 in the experimental and control arms, respectively.

After analysis, the researchers found a statistically significant reduction in opioid consumption over the first 2 weeks following TSA; however, the opioid sparing effect was not clinically meaningful.

Overall, opioid consumption was lower in the experimental arm from 24 to 72 hours, days 4 to 7, and days 8 to 14—translating to reductions by a factor of 1.80, 1.95, and 2.18, respectively. However, the differences in terms of morphine milligram equivalents were modest—30.4 ± 30.1 vs. 54.8 ± 36.7, 18.7 ± 26.3 vs. 36.4 ± 39.4, and 10.7 ± 28.1 vs. 23.3 ± 41.9, respectively.

With respect to pain intensity, scores were significantly lower in the experimental arm on days 7 and 14—50.8 ± 7.6 vs. 46.6 ± 7.4 and 45.4 ± 6.2 vs. 42.4 ± 7.9, respectively.

“We weren’t surprised by the findings,” says Dr. Virk. “Other studies have shown similar results—no clinically significant difference between the use of bupivacaine alone and when LB is added.”

Clinical and Economic Implications

According to Dr. Virk, these findings have important implications. While LB may not be appropriate for every patient, it could be benefit certain high-risk groups, such as those with opioid use disorder or elevated baseline pain.

From an economic perspective, the differential in cost associated with LB use hinders its widespread adoption, Dr. Virk explains. “These findings could be relevant to the economic decision of whether or not to choose LB,” he says.