Patients receiving liposomal bupivacaine (Exparel, Pacira) injection after total knee arthroplasty (TKA) spent less time in the hospital and were significantly less likely to need to go to a rehabilitation center after discharge, a recent study found.
Patients given liposomal bupivacaine spent a half-day less in the hospital than those administered routine, opioid-based pain medications, according to the review of patient records by researchers at Philadelphia College of Osteopathic Medicine; Plano Orthopedics and Sports Medicine, in Texas; and the Rubin Institute for Advanced Orthopedics at the Sinai Hospital of Baltimore.
“The results of this analysis are encouraging because they suggest that the use of [liposomal bupivacaine] not only allows us to get our patients up and out of the hospital sooner, but also increases the likelihood we can send them directly home,” said Michael Mont, MD, director of the Center for Joint Preservation and Replacement at the Rubin Institute for Advanced Orthopedics, and an author of the poster.
The study was presented at the American Academy of Orthopaedic Surgeons 2016 annual meeting, and was supported by Pacira Pharmaceuticals.
Very Large Retrospective Study
The retrospective analysis examined records from the Premier hospital discharge database, looking at patients aged 18 years and older who underwent TKA between July 1, 2013, and June 30, 2014.
The study compared hospitalization duration and discharge information between 80,160 patients who were treated with standard analgesics and 14,668 patients who received liposomal bupivacaine.
The liposomal bupivacaine cohort consisted of 9,211 women and 5,457 men, and there were 49,699 women and 30,461 men in the group receiving the standard pain treatment regimen. The mean age in both groups was 66 years.
The hospital length of stay (LOS) analysis used a linear model with a negative binomial distribution, controlled for age, sex, race, geographic region, Charlson Comorbidity Index and operating time, according to the study. The discharge analysis—the percentage of patients who went directly home—used logistic regression with the same controls.
Liposomal bupivacaine is administered in a single dose and injected into the surgical site, with bupivacaine releasing over time. The product pairs bupivacaine with DepoFoam, a delivery technology.
Shorter Hospital LOS, Modest Cost Savings
Liposomal bupivacaine patients stayed in the hospital 2.58 days, compared with 2.98 for the group given standard pain medications. Of patients receiving liposomal bupivacaine, 73.2% were discharged directly to home, compared with 66% of those treated with routine analgesics.
“The ability to recover at home, rather than in a short-term nursing facility or rehabilitation center, not only lends itself to favorable hospital economics, but also—importantly—toward a more comfortable patient recovery experience,” said Dr. Mont.
The study suggests that liposomal bupivacaine has the potential to be an alternative to standard pain treatments, which often use opioids with their attendant side effects, including nausea, vomiting and respiratory depression, all of which can lead to longer hospital LOS followed by rehab therapy.
“These results are encouraging and suggest that liposomal bupivacaine may represent a promising addition to current multimodal pain management regimens,” the study noted.
Although costs were not examined in-depth, there was a modest savings of $300 per patient per day in the liposomal bupivacaine group. While this is not a huge number on an individual basis, collectively the savings could add up.
“If you have a savings of $300 per day at a hospital that provides this treatment for 1,000 patients yearly, on a national level, I think it’s pretty substantial,” said Jaydev Mistry, MD, an orthopedic research fellow to Dr. Mont.
Despite the positive findings, Gaurav Rajpal, MD, assistant professor at the University of Massachusetts Medical School, in Worcester, said he found some limitations with the study.
Because it was a retrospective study, Dr. Rajpal noted that it is not clear what factors were considered when deciding whether to give a patient liposomal bupivacaine.
There was also no information on how much of the drug different patients received, nor any discussion of rescue analgesics or how the two groups fared on pain scores.
Based on these issues, he argued that t he study does not provide enough data on which to base a conclusion. “We need a large prospective study,” Dr. Rajpal said.
In contrast, although Adriana Desillier, MD, an anesthesiologist at Tufts Medical Center, in Boston, agreed the study had some limitations as a retrospective analysis, she was encouraged by the data.
Dr. Desillier sees the potential for reducing reliance on opioid pain medications and for potentially lower costs by reducing hospital LOS.
“This is a very interesting and promising study,” Dr. Desillier said. “It definitely provides some guidance on the use of liposomal bupivacaine while at the same time reducing the cost by decreasing [hospital LOS].”