Use of liposomal bupivacaine in the postoperative management of posterior spinal decompression.

OBJECTIVE The aim in this paper was to evaluate the efficacy of long-acting liposomal bupivacaine in comparison with bupivacaine hydrochloride for lowering postoperative analgesic usage in the management of posterior cervical and lumbar decompression and fusion. METHODS A retrospective cohort-matched chart review of 531 consecutive cases over 17 months (October 2013 to February 2015) for posterior cervical and lumbar spinal surgery procedures performed by a single surgeon (J.J.) was performed. Inclusion criteria for the analysis were limited to those patients who received posterior approach decompression and fusion for cervical or lumbar spondylolisthesis and/or stenosis. Patients from October 1, 2013, through December 31, 2013, received periincisional injections of bupivacaine hydrochloride, whereas after January 1, 2014, liposomal bupivacaine was solely administered to all patients undergoing posterior approach cervical and lumbar spinal surgery through the duration of treatment. Patients were separated into 2 groups for further analysis: posterior cervical and posterior lumbar spinal surgery. RESULTS One hundred sixteen patients were identified: 52 in the cervical cohort and 64 in the lumbar cohort. For both cervical and lumbar cases, patients who received bupivacaine hydrochloride required approximately twice the adjusted morphine milligram equivalent (MME) per day in comparison with the liposomal bupivacaine groups (5.7 vs 2.7 MME, p = 0.27 [cervical] and 17.3 vs 7.1 MME, p = 0.30 [lumbar]). The amounts of intravenous rescue analgesic requirements were greater for bupivacaine hydrochloride in comparison with liposomal bupivacaine in both the cervical (1.0 vs 0.39 MME, p = 0.31) and lumbar (1.0 vs 0.37 MME, p = 0.08) cohorts as well. None of these differences was found to be statistically significant. There were also no significant differences in lengths of stay, complication rates, or infection rates. A subgroup analysis of both cohorts of opiate-naive versus opiate-dependent patients found that those patients who were naive had no difference in opiate requirements. In chronic opiate users, there was a trend toward higher opiate requirements for the bupivacaine hydrochloride group than for the liposomal bupivacaine group; however, this trend did not achieve statistical significance. CONCLUSIONS Liposomal bupivacaine did not appear to significantly decrease perioperative narcotic use or length of hospitalization, although there was a trend toward decreased narcotic use in comparison with bupivacaine hydrochloride. While the results of this study do not support the routine use of liposomal bupivacaine, there may be a benefit in the subgroup of patients who are chronic opiate users. Future prospective randomized controlled trials, ideally with dose-response parameters, must be performed to fully explore the efficacy of liposomal bupivacaine, as the prior literature suggests that clinically relevant effects require a minimum tissue concentration.