Admixture of Liposomal Bupivacaine and Bupivacaine Hydrochloride for Peripheral Nerve Blocks in Adolescents Undergoing Orthopedic Surgery: An Observational Cohort Study

Abstract

Background/Objectives: In 2021, the Food and Drug Administration approved liposomal bupivacaine injectable suspension for single-dose infiltration in patients ≥ 6 years of age. Liposomal bupivacaine and bupivacaine hydrochloride admixtures may also be administered off-label for pediatric regional anesthesia including peripheral nerve blocks (PNBs). This single-injection, long-acting technique is not well described in pediatrics but may have benefits over traditional continuous catheter-based systems. The purpose of this investigation was to examine an adolescent cohort who received liposomal bupivacaine/bupivacaine hydrochloride PNBs for orthopedic surgery. Methods: Patient, surgical, anesthetic, block characteristics, and post-anesthesia care unit (PACU) outcomes were retrospectively reviewed from February 2020 to June 2024. From February to December 2022, a short follow-up survey was conducted to assess post-discharge patient-reported outcomes. Results: There were 524 liposomal bupivacaine/bupivacaine hydrochloride PNBs (106 upper-extremity and 418 lower-extremity) performed in 374 patients with a mean (standard deviation, range) age of 16 (1.2, 11-17) years. Two unilateral PNBs were performed in 150 (40%) patients to ensure an adequate sensory neural blockade. The interscalene (n = 81, 15%) and adductor canal (n = 140, 27%) blocks were the most common upper- and lower-extremity PNBs, respectively. Intraoperatively, the majority of the cohort (n = 258, 69%) underwent monitored anesthesia care (MAC). No patient required conversion from MAC to general anesthesia due to pain. In PACU, 288 (77%) patients reported no pain. Mild and moderate pain were reported by 56 (15%) and 30 (8%) patients, respectively. No patients developed local anesthetic toxicity. The survey results (n = 66) indicate that the majority of patients (96%) were satisfied with block analgesia postoperatively. Conclusion: Liposomal bupivacaine/bupivacaine hydrochloride PNBs were used successfully in adolescents undergoing a variety of orthopedic surgeries.

Keywords: liposomal bupivacaine; local anesthetics; pain management; pediatrics; regional anesthesia.

Figure 1

Peripheral nerve block (PNB) combinations, n = 524. Data are presented as n (%). Figure 1 Legend: The distribution of combination and single PNBs are shown as n (%).

Figure 2

Liposomal bupivacaine doses in milligrams, n = 374. Figure 2 Legend. The distribution of liposomal bupivacaine doses is shown.

Figure 3

Average patient PACU pain scores, n = 374. Figure 3 Legend: The distribution of average PACU pain scores for the cohort is shown. A total of 288 patients (77%) reported no pain in PACU. Mild pain was reported by 56 patients (15%), and moderate pain was reported by 30 patients (8%). No patients reported severe pain.