A phase 3, randomized, placebo-controlled trial of DepoFoam® bupivacaine (extended-release bupivacaine local analgesic) in bunionectomy

Extended Release of Bupivacaine from Temperature-Responsive PNDJ Hydrogels Improves Postoperative Weight-Bearing in Rabbits Following Knee Surgery

Effective treatment of postoperative pain lasting for multiple days without opioids is an important clinical need. We previously reported analgesia lasting up to 96 h in a porcine soft tissue model of postoperative pain using SBG004, an extended-release formulation of bupivacaine based on the temperature-responsive polymer poly(N-isopropylacrylamide-co-dimethylbutyrolactone acrylamide-co-Jeffamine M-1000 acrylamide) [PNDJ]. Orthopaedic surgical sites such as the knee can involve complex sensory innervation which presents a distinct challenge to local anesthetic delivery. The purpose of this work was to evaluate the pharmacokinetics and efficacy of SBG004 in an orthopaedic surgical model in comparison to currently available local anesthetics. Pharmacokinetics following periarticular (PA) or intraarticular (IA) injection of SBG004 were compared against liposomal bupivacaine (Lip-Bupi) PA in New Zealand White rabbits (all doses 14.5 mg/kg). Analgesic efficacy of SBG004 (IA, PA, or IA + PA), three active comparators, and saline was evaluated following knee surgery in New Zealand White rabbits. Analgesia was assessed via weight-bearing on the operated limb during spontaneous large steps in video recordings. Systemic bupivacaine exposure lasted at least 7 days for SBG004 PA, 4 days for SBG004 IA, and 2 days for Lip-Bupi PA. In the analgesia study, weight-bearing in all active groups except SBG004 IA was more frequent versus saline through 8 h postoperatively (p < 0.05). Only SBG004 IA + PA resulted in a higher proportion of weight-bearing rabbits at 24 h versus saline (6/7 versus 2/10, p = 0.015). Analysis of pooled data from 24-72 h showed significantly greater frequency of weight-bearing in rabbits receiving SBG004 IA + PA (71%) versus saline (37%), ropivacaine cocktail (41%), and Lip-Bupi PA (36%). The results indicate that the release profile from SBG004 PA or IA coincides reasonably with the time course of postoperative pain, and SBG004 may produce longer duration of analgesia than local anesthetics currently used in knee surgery, including during the period of 24-72 h recognized as a target for extended-release local anesthetics.

The use of liposomal bupivacaine in fracture surgery: a review

Historically, opioids have played a major role in the treatment of postoperative pain in orthopedic surgery. A multitude of adverse events have been associated with opioid use and alternative approaches to pain relief are being investigated, with particular focus on multimodal pain management regimens. Liposomal bupivacaine (EXPAREL) is a component of some multimodal regimens. This formulation of bupivacaine encapsulates the local anesthetic into a multivesicular liposome to theoretically deliver a consistent amount of drug for up to 72 hours. Although the use of liposomal bupivacaine has been studied in many areas of orthopedics, there is little evidence evaluating its use in patients with fractures. This systematic review of the available data identified a total of eight studies evaluating the use of liposomal bupivacaine in patients with fractures. Overall, these studies demonstrated mixed results. Three studies found no difference in postoperative pain scores on postoperative days 1-4, while two studies found significantly lower pain scores on the day of surgery. Three of the studies evaluated the quantity of narcotic consumption postoperatively and failed to find a significant difference between control groups and groups treated with liposomal bupivacaine. Further, significant variability in comparison groups and study designs made interpretation of the available data difficult. Given this lack of clear evidence, there is a need for prospective, randomized clinical trials focused on fully evaluating the use of liposomal bupivacaine in fracture patients. At present, clinicians should maintain a healthy skepticism and rely on their own interpretation of the available data before widely implementing the use of liposomal bupivacaine.

Pain Reduction With AbobotulinumtoxinA for the Treatment of Hallux Valgus in Adult Participants: Results of a Randomized and Placebo-Controlled Phase 2 Trial

AbobotulinumtoxinA (aboBoNT-A, Dysport® [Ipsen, Paris, France]) inhibits acetylcholine release at the neuromuscular junction and may modulate pain signaling in hallux valgus (HV). This randomized study (NCT03569098) included a double-blind phase (aboBoNT-A 300U, 500U or placebo injections into forefoot muscles) and an open-label aboBoNT-A treatment period in participants with an HV diagnosis and no HV surgery. The primary endpoint was change from baseline in numeric pain rating scale (NPRS) score at week 8. Secondary endpoints included change in NPRS (other time points) and proportion of participants with ≥20% reduction from baseline NPRS (responders). Post-hoc analyses assessed number of days in a 7-day evaluation period that participants spent in a lower pain state than at baseline. Participants received aboBoNT-A 300U (n = 63), 500U (n = 60) or placebo (n = 63). Superiority to placebo was not observed with either aboBoNT-A dose at week 8, thus the primary endpoint was unmet. At week 12, a trend toward efficacy was observed with aboBoNT-A 500U versus placebo and the proportion of participants with ≥20% reduction from baseline NPRS was greater with aboBoNT-A 500U versus placebo (p = .006). Participants in the aboBoNT-A 500U group spent more days with lower NPRS than their lowest baseline score, and with NPRS ≥2 points lower than their mean baseline NPRS at weeks 8 and 12 versus placebo (all p < .05; post-hoc). AboBoNT-A was well tolerated. Although the primary endpoint was unmet, other endpoints showed a nominal advantage for aboBoNT versus placebo for treatment of HV-related pain, particularly at week 12. Further clinical evaluation is needed to establish whether botulinum toxins represent a viable non-operative treatment option for HV-associated pain. PLAIN LANGUAGE SUMMARY: Hallux valgus is the medical name for a bunion, a foot deformity that can worsen over time. Patients with bunions experience pain and walking can become difficult, which can affect their quality of life. Foot support aids (e.g., braces, splints and inserts) are available, but surgery is the standard treatment. This study looked at how injections of a specific type of botulinum toxin, called abobotulinumtoxinA or "aboBoNT-A", into the foot may help to reduce pain in patients with bunions. The study included 186 patients aged 18 to 75 years who had not had surgery on their bunion. The researchers looked at how well the injections worked using scales that measure the pain levels the patient experienced. The main outcome was whether patients who had aboBoNT-A injections had less pain after 8 weeks than they did before treatment. The study included patients who were injected with saltwater (no treatment) to check that any treatment effect was real. Researchers also looked at the results after 12 weeks, as well as how many patients had less pain after treatment than before and how many days in a given week patients experienced less pain after treatment than they did before. There was no reduction in pain levels with aboBoNT-A injections after 8 weeks compared with no treatment. However, the other study outcomes suggested that aboBoNT-A resulted in a small benefit compared with no treatment, especially after 12 weeks. Further medical research is needed to establish whether botulinum toxins represent an alternative treatment to surgery for the pain associated with bunions.

The Impact of Hospital Size and Teaching Status on Outcomes Following Total Ankle Arthroplasty

The popularity and utilization of total ankle arthroplasty (TAA) as treatment for ankle arthritis has increased exponentially from 1998 to 2012. Overall the outcomes have improved for TAA with the introduction of new-generation implants and this has increased the focus on optimizing other variables affecting outcomes for TAA. The purpose of this study was to examine the effects of hospital characteristics and teaching status on outcomes for TAA. The Nationwide Inpatient Sample database was queried from 2002 to 2012 using the ICD-9 procedure code for TAA. The primary outcomes evaluated included: in-hospital mortality, length of stay, total hospital charges, discharge disposition, perioperative complications, and patient demographics. Analyses were carried out based on hospital size: small, medium, and large; and teaching status: rural nonteaching, urban nonteaching, and urban teaching. A total weighted national estimate of 16,621 discharges for patients undergoing TAA was reported over the 10-year period. There were significant differences in length of stay and total charges between all hospitals when comparing location and teaching status; however, no significant differences were noted for in-hospital mortality. Rural, nonteaching hospitals had higher odds of perioperative complications. There were also significant differences in length of stay and total charges when comparing hospital sizes. Overall, there is no increased risk of mortality after TAA regardless of hospital size or setting. However, rural hospitals had increased rates of perioperative complications compared to urban hospitals. Our analyses demonstrated important factors affecting cost and resource utilization for TAA, clearly additional work is needed to optimize this relationship, especially in the upcoming bundled payment models.

The effect of liposomal bupivacaine for surgical wound infiltration: A meta‐analysis of randomised controlled trials

Liposomal bupivacaine (LB) has consistently been considered a potential analgesic for surgical wound infiltration. However, the evidence of its analgesic effectiveness remains unclear. In this meta-analysis, we attempted to identify the potential clinical role of LB wound infiltration in different surgical procedures. Randomised controlled trials (RCTs) comparing LB with non-liposomal local anaesthetics and placebos were retrieved from six electronic databases. The primary outcome was cumulative morphine equivalent consumption within 24, 48, and 72 hours after surgery. Approximately 2659 patients from 22 studies were included in the meta-analysis. Compared to the control, LB-wound infiltration did not reduce the postoperative morphine consumption at 24 hours (weighted mean difference [WMD], -0.60 mg; 97.5% confidence interval [CI], -2.78 to 1.59 mg; P = 0.54), 48 hours (WMD, -1.00 mg; 97.5% CI, -3.23 to 1.24; P = 0.32) or 72 hours (WMD, 0.50 mg; 97.5% CI, -0.67 to 1.67; P = 0.33). Similarly, secondary outcome analysis did not reveal any additional benefits of LB in any other pain-related outcomes. LB was not associated with any adverse effects. Overall, LB does not appear to improve the postoperative analgesic, rehabilitation, or safety outcomes. Current evidence does not support the routine use of LB for wound infiltration following surgical procedures.

A novel long-acting local anesthetic - HTX-011 (ZYNRELEF™) for postoperative pain control

INTRODUCTION

Pain following most surgical procedures is expected. However, the treatment and management of postoperative surgical pain has remained challenging. The use of opioid therapy has increasingly become controversial given the limited therapeutic window of these drugs, the adverse side effects, and the potential for abuse. A multimodal approach to the treatment of postoperative pain has been shown to improve pain outcomes after surgery and improve patient satisfaction. Here, we examine a new formulation of bupivacaine and meloxicam extended-release solution HTX-011 (Zenrelef®), and its efficacy in postoperative pain control.

AREAS COVERED

HTX-011 exists as an extended-release polymer that controls the release of the active ingredients over 72 hours. A systematic approach was taken to review PubMed (Medline) for prospective and retrospective studies related to the use of HTX-011 for the management of postoperative pain.

EXPERT OPINION

HTX-011 represents a new tool to help modulate postoperative pain. Although multimodal analgesia has been effective in managing postoperative pain, direct surgical infiltration with local anesthetics has had limited efficacy due to their short duration of action. The HTX-011 formulation provides a long-acting local anesthetic at the surgical site which provides a longer period of analgesia while maintaining a favorable safety profile.

Pharmacokinetics and local tissue response to local instillation of vocacapsaicin, a novel capsaicin prodrug, in rat and rabbit osteotomy models

Vocacapsaicin is a novel prodrug of trans-capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) being developed as a nonopioid, long-lasting, site-specific treatment for postsurgical pain management. The objective of these studies was to examine the safety and tolerability of vocacapsaicin in an osteotomy model in two animal species and to evaluate bone healing parameters. Rats undergoing unilateral femoral osteotomy received a single perioperative administration (by instillation) of vocacapsaicin (vehicle, 0.15, 0.3, and 0.6 mg/kg). Rabbits undergoing unilateral ulnar osteotomy received a single perioperative administration (by infiltration and instillation) of vocacapsaicin (vehicle, 0.256 and 0.52 mg) alone or in combination with 0.5% ropivacaine. Clinical signs, body weights, food consumption, radiography, histopathologic examinations, ex vivo bone mineral density measurements (rats only), and biomechanical testing were evaluated at 4 and 8 weeks in rats and at 2 and 10 weeks in rabbits. Plasma samples were also collected in rabbits. There were no vocacapsaicin-related effects on mortality, clinical observations, body weight, or food consumption in either species. Systemic exposure to vocacapsaicin and its metabolites, including capsaicin, was transient. In rats, vocacapsaicin was devoid of deleterious effects on bone healing parameters, and there was a trend for enhanced bone healing in rats treated with the mid-dose. In rabbits, vocacapsaicin administered alone or in combination with ropivacaine did not adversely affect bone healing parameters. In conclusion, a single perioperative administration of vocacapsaicin in unilateral osteotomy models was well tolerated, locally and systemically, supporting its continued development as a novel, nonopioid treatment for postsurgical pain management.

Liposomal bupivacaine in posterior spine surgery: A piece of the puzzle for postoperative pain

Background

Liposomal bupivacaine (LB) is a local analgesic that may be used at the time of surgery to limit postoperative pain around the surgical site. Its efficacy in decreasing pain, decreasing narcotic consumption, decreasing length of stay, and improving mobility is an area of intense research. The purpose of this study was to determine whether LB use was associated with improved patient-reported pain scores in the first 72 h following posterior spinal surgery, decreased postoperative narcotic need, and decreased length of stay.

Methods

One hundred and five patients undergoing elective posterior cervical or lumbar surgery were included in retrospective analysis. Forty-eight patients who received LB intraoperatively were compared with a historical cohort of 56 patients who underwent similar procedures and did not receive postsurgical infiltration with local analgesia. The same pain medication protocol was utilized postoperatively.

Results

Demographics, clinical characteristics, and total morphine milligram equivalents did not differ significantly between the groups. The treatment group averaged a decreased length of stay (1.85 days treatment, 2.68 days control, p = 0.057). Treatment with LB was associated with lower pain levels at 24 h (5.2 treatment, 6.4 control, p = 0.04) and 48-72 h (4.9 treatment, 6.6 control, p = 0.007) after surgery.

Conclusions

LB improved patient perception of pain in the acute postoperative time period.Intraoperative LB injection, coupled with focused early mobilization efforts and multimodal pain control, may lead to improved patient-reported outcomes, shorter length of stay, and decreased risk of perioperative complications.

Evaluation of liposomal bupivacaine infiltration at reconstructive skin graft donor sites in adolescent and young adult burn patients: A retrospective analysis

BACKGROUND

Postoperative pain at skin graft donor sites is frequently undertreated in burn patients, which can impair reconstructive outcomes and result in harmful psychological consequences. We find a critical need to explore and promote non-opioid, multimodal analgesics. Donor site infiltration of the local anesthetic liposomal bupivacaine in adolescent and young adult burn patients has not been previously investigated. Therefore, the goal of this study was to evaluate intraoperative liposomal bupivacaine infiltration for postoperative donor site pain control in adolescent and young adult burn patients undergoing reconstructive skin graft procedures.

METHODS

This retrospective analysis included patients aged 14-25 years, who underwent at least two reconstructive skin graft procedures, one that received donor site infiltration of the standard treatment (bupivacaine hydrochloride) and one that received donor site infiltration of liposomal bupivacaine. The final sample included 30 patients with a total of 44 liposomal bupivacaine cases and 53 standard treatment cases analyzed.

RESULTS

In the authors' five-year experience, the use of liposomal bupivacaine compared to standard treatment was associated with statistically significant decreases in 0-4 h postoperative pain scores (mean 1.4/10 versus 2.3/10, p = 0.04) and 0-24 h postoperative pain scores (mean 1.7/10 versus 2.4/10, p = 0.02). Neither analgesic was associated with adverse events. Differences in length of stay and inpatient postoperative opioid usage were not regarded as significant.

CONCLUSION

In this retrospective analysis, the authors report the first results that suggest intraoperative liposomal bupivacaine donor site infiltration may be associated with statistically improved patient outcomes in adolescent and young adult burn patients. However, the reported differences are most likely not clinically significant, establishing the necessity for further evaluation of using liposomal bupivacaine in this unique patient population.

Ultrasound-Triggered on Demand Lidocaine Release Relieves Postoperative Pain

Safe and non-invasive on-demand relief is a crucial and effective treatment for postoperative pain because it considers variable timing and intensity of anesthetics. Ultrasound modulation is a promising technique for this treatment because it allows convenient timed and non-invasive controlled drug release. Here, we created an ultrasound-triggered lidocaine (Lido) release platform using an amino acid hydrogel functioning as three-dimensional (3D) scaffold material (Lido-PPIX@ER hydrogel). It allows control of the timing, intensity and duration of lidocaine (Lido) to relieve postoperative pain. The hydrogel releases Lido due to the elevated reactive oxygen species (ROS) levels generated by PPIX under ultrasound triggering. The Lido-PPIX@ER hydrogel under individualized ultrasound triggering released lidocaine and provided effective analgesia for more than 72 h. The withdrawal threshold was higher than that in the control group at all time points measured. The hydrogel showed repeatable and adjustable ultrasound-triggered nerve blocks in vivo, the duration of which depended on the extent and intensity of insonation. On histopathology, no systemic effect or tissue reaction was observed in the ultrasound-triggered Lido-PPIX@ER hydrogel-treated group. The Lido-PPIX@ER hydrogel with individualized (highly variable) ultrasound triggering is a convenient and effective method that offers timed and spatiotemporally controlled Lido release to manage postoperative pain. This article presents the delivery system for a new effective strategy to reduce pain, remotely control pain, and offer timed and spatiotemporally controlled release of Lido to manage postoperative pain.

Robust gelatin hydrogels for local sustained release of bupivacaine following spinal surgery

Adequate treatment of pain arising from spinal surgery is a major clinical challenge. Opioids are the mainstay of current treatment methods, but the frequency and severity of their side effects display a clear need for opioid-free analgesia. Local anesthetics have been encapsulated into sustained-release drug delivery systems to provide postoperative pain relief. However, these formulations are limited by rapid diffusion out of the surgical site. To overcome this limitation, we synthesized ring-shaped hydrogels incorporating bupivacaine, designed to be co-implanted with pedicle screws during spinal surgery. Hydrogels were prepared by riboflavin-mediated crosslinking of gelatin functionalized with tyramine moieties. Additionally, oxidized β-cyclodextrin was introduced into the hydrogel formulation to form dynamic bonds with tyramine functionalities, which enables self-healing behavior and resistance to shear. Feasibility of hydrogel implantation combined with pedicle screws was qualitatively assessed in cadaveric sheep as a model for instrumented spinal surgery. The in-situ crystallization of bupivacaine within the hydrogel matrix provided a moderate burst decrease and sustained release that exceeded 72 hours in vitro. The use of bupivacaine crystals decreased drug-induced cytotoxicity in vitro compared to bupivacaine HCl. Thus, the presented robust hydrogel formulation provides promising properties to enable the stationary release of non-opioid analgesics following spinal surgery. STATEMENT OF SIGNIFICANCE: Currently, postoperative pain following spinal surgery is mainly treated with opioids. However, the use of opioids is associated with several side effects including addiction. Here we developed robust and cytocompatible gelatin hydrogels, prepared via riboflavin-mediated photocrosslinking, that can withstand orthopedic implantation. The implantability was confirmed in cadaveric instrumented spinal surgery. Further, hydrogels were loaded with bupivacaine crystals to provide sustained release beyond 72 hours in vitro. The use of crystallized bupivacaine decreased cytotoxicity compared to bupivacaine HCl. The present formulation can aid in enabling opioid-free analgesia following instrumented spinal surgery.

Novel temperature-responsive hydrogel injected to the incision site for postoperative pain relief in laparoscopic abdominal surgery: a single-blind, randomized, pivotal clinical trial

BACKGROUND

A temperature-responsive hydrogel (PF-72; TGel Bio, Inc., Ltd, Seoul, Korea), developed as a sustained drug delivery device, can be mixed with ropivacaine to reduce pain in the incision area. The hydrogel is soluble at low temperatures (2-8 °C) and is converted into a gel at high temperatures (> 30 °C). We aimed to evaluate whether the administration of ropivacaine using PF-72 at incision sites reduces pain until 72 h postoperatively in patients undergoing laparoscopic stomach or colorectal surgery.

METHODS

Patients were randomly assigned to the control group (0.75% ropivacaine) or PF-72 group (PF-72 mixed with 0.75% ropivacaine). Before surgical incision closure, 0.75% ropivacaine or PF-72 mixed with 0.75% ropivacaine was injected into the subcutaneous fat and muscle of all incisions. Postoperative pain was evaluated by the Numerical Rating Scale (NRS, 0 = no pain, 10 = most severe pain) for wound pain at 3, 6, 24, 48, and 72 h after the end of surgery.

RESULTS

Ninety-nine patients (control, n = 51; PF-72, n = 48) were included in the analysis. The areas under the curve of NRS for wound pain until 72 h in the control group and the PF-72 group were 188.7 ± 46.1 and 135.3 ± 49.9 h, respectively (P < 0.001). The frequency of the administration of rescue analgesics in the general ward was similar between the two groups.

CONCLUSION

PF-72 mixed with 0.75% ropivacaine reduced postoperative pain until 72 h in patients undergoing laparoscopic surgery. Although the study population was not large enough for safety evaluation, no adverse events associated with PF-72 were observed.

Comparison of in vitro and in vivo Toxicity of Bupivacaine in Musculoskeletal Applications

The recent societal debate on opioid use in treating postoperative pain has sparked the development of long-acting, opioid-free analgesic alternatives, often using the amino-amide local anesthetic bupivacaine as active pharmaceutical ingredient. A potential application is musculoskeletal surgeries, as these interventions rank amongst the most painful overall. Current literature showed that bupivacaine induced dose-dependent myo-, chondro-, and neurotoxicity, as well as delayed osteogenesis and disturbed wound healing in vitro. These observations did not translate to animal and clinical research, where toxic phenomena were seldom reported. An exception was bupivacaine-induced chondrotoxicity, which can mainly occur during continuous joint infusion. To decrease opioid consumption and provide sustained pain relief following musculoskeletal surgery, new strategies incorporating high concentrations of bupivacaine in drug delivery carriers are currently being developed. Local toxicity of these high concentrations is an area of further research. This review appraises relevant in vitro, animal and clinical studies on musculoskeletal local toxicity of bupivacaine.

Efficacy of Liposomal Bupivacaine for Sternotomy Pain After Cardiac Surgery: A Retrospective Analysis

BACKGROUND

Multimodal analgesia is a cornerstone of postoperative pain management. Different formulations of local anesthetics are available. Data to support these treatment options are limited.

OBJECTIVE

To determine the efficacy of liposomal bupivacaine compared with bupivacaine or ropivacaine in patients undergoing sternotomy for coronary artery bypass graft (CABG) and/or valve surgery.

METHODS

Single-center, retrospective, observational study at a community teaching hospital. Patients included were 18 years of age or older undergoing CABG and/or valve surgery via median sternotomy and received either liposomal bupivacaine or an active comparator. The primary outcome was opioid utilization in morphine milligram equivalent (MME) from 0 to 72 hours.

RESULTS

A total of 376 patients were included, 223 in the liposomal bupivacaine arm and 153 in the active comparator arm. There was no difference in the MME use from 0 to 72 hours among patients in the liposomal bupivacaine group compared with the comparator group (114.2 mg [75.55] vs 107.6 mg [68.4], P = 0.38). After Bonferroni correction, there was no difference in pain scores at individual time points. At 24- and 48-hour post-op, pain scores were higher with liposomal bupivacaine at 4.4 (2.7) vs 3.5 (2.8) (P = 0.01) and 3.1 (2.9) vs 2.4 (2.6) (P = 0.02).

CONCLUSION AND RELEVANCE

Based on these findings and previous studies, liposomal bupivacaine should not be routinely used for CABG and/or valve surgery through a median sternotomy given lack of superiority. This helps inform surgical practice to the role of anesthetics as part of the multimodal analgesia regimen.

Intercostal liposomal bupivacaine injection for rib fractures: A prospective randomized controlled trial

BACKGROUND

Blunt chest wall injury accounts for 15% of trauma admissions. Previous studies have shown that the number of rib fractures predicts inpatient opioid requirements, raising concerns for pharmacologic consequences, including hypotension, delirium, and opioid dependence. We hypothesized that intercostal injection of liposomal bupivacaine would reduce analgesia needs and improve spirometry metrics in trauma patients with rib fractures.

METHODS

A prospective, double-blinded, randomized placebo-control study was conducted at a Level I trauma center as a Food and Drug Administration investigational new drug study. Enrollment criteria included patients 18 years or older admitted to the intensive care unit with blunt chest wall trauma who could not achieve greater than 50% goal inspiratory capacity. Patients were randomized to liposomal bupivacaine or saline injections in up to six intercostal spaces. Primary outcome was to examine pain scores and breakthrough pain medications for 96-hour duration. The secondary endpoint was to evaluate the effects of analgesia on pulmonary physiology.

RESULTS

One hundred patients were enrolled, 50 per cohort, with similar demographics (Injury Severity Score, 17.9 bupivacaine 17.6 control) and comorbidities. Enrolled patients had a mean age of 60.5 years, and 47% were female. Rib fracture number, distribution, and targets for injection were similar between groups. While both groups displayed a decrease in opioid use over time, there was no change in mean daily pain scores. The bupivacaine group achieved higher incentive spirometry volumes over Days 1 and 2 (1095 mL, 1063 mL bupivacaine vs. 900 mL, 866 mL control). Hospital and intensive care unit lengths of stay were similar and there were no differences in postinjection pneumonia, use of epidural catheters or adverse events bet ween groups.

CONCLUSION

While intercostal liposomal bupivacaine injection is a safe method for rib fracture-related analgesia, it was not effective in reducing pain scores, opioid requirements, or hospital length of stay. Bupivacaine injection transiently improved incentive spirometry volumes, but without a reduction in the development of pneumonia.

LEVEL OF EVIDENCE

Therapeutic/care management, Level II.

Efficacy of Liposomal Bupivacaine versus Ropivacaine in Adductor Canal Block for Total Knee Arthroplasty

Adductor canal block (ACB) is advantageous for postoperative analgesia in total knee arthroplasty (TKA) because it results in minimal motor block. Liposomal bupivacaine (LB) is Food and Drug Administration-approved extended-release formulation of bupivacaine for interscalene peripheral nerve blocks. Its use is increasing in the TKA setting, mainly as a local infiltration agent. We compared the efficacy of ACB using LB versus ropivacaine in TKA. Two cohorts of patients were retrospectively analyzed at a single institution receiving ropivacaine and LB ACB for TKA. Duration of LB ACB, time to first opioid use postrecovery room, amount of opioid use postrecovery room, length of stay (LOS), and average and highest pain scores were collected. A total of 91 and 142 TKA patients received ropivacaine and LB for ACB, respectively. At 8 hours postrecovery room, more patients in the LB group required no opioids compared with the ropivacaine group (p = 0.026). Mean opioid consumption was lower in the LB group than in the ropivacaine group at 8 and 24 hours postrecovery room, although statistical significance was only observed at 8 hours (p = 0.022). The highest pain score for patients in the two groups was not statistically different. The average pain score for patients with a 2-day LOS was higher in the LB group, but average pain scores were similar for patients with 1- and 3-day LOS. Median LOS for the LB and ropivacaine groups was 1 and 2 days, respectively (p < 0.0001). Significantly lower opioid use at 8 hours postrecovery room was seen in the LB group compared with the ropivacaine group. There was no difference in opioid use at 24 and 48 hours. There was also no advantage with LB ACB in decreasing pain scores. However, the LB ACB group demonstrated a significantly shorter LOS compared with the ropivacaine ACB group.

Anesthesia in Total Shoulder Arthroplasty: A Systematic Review and Meta-Analysis

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For shoulder arthroplasty, regional anesthesia is safer when compared with general anesthesia. There is insufficient evidence to demonstrate the superiority of regional anesthesia with respect to pulmonary complications and hospital length of stay.

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Infiltration of the shoulder with local anesthetics offers no additional benefits compared with single-shot or continuous brachial plexus blocks for shoulder arthroplasty.

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There is high-quality evidence (Level I) demonstrating lower pain scores and lower perioperative opioid requirements after a continuous peripheral nerve block compared with a single-shot nerve block. However, catheter dislodgment and logistical issues with catheter insertion are impediments to the widespread usage of a continuous nerve block with an indwelling catheter.

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Liposomal bupivacaine is comparable with non-liposomal local anesthetic agents with respect to pain relief, the opioid-sparing effect, and adverse effects in the first 48 hours after total shoulder arthroplasty.

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Perioperative dexamethasone administration improves postoperative pain control, decreases perioperative opioid requirements, and reduces postoperative nausea.

Evaluation of bupivacaine liposome injectable suspension efficacy in single-use vials over five days of multiple use

OBJECTIVE

To test the anesthetic effect of a bupivacaine liposome injectable suspension (BLIS), used in a multiple-dose manner for up to 5 consecutive days.

STUDY DESIGN

Prospective, randomized, experimental study.

ANIMALS

A total of 30 male and female Sprague-Dawley rats (Rattus norvegicus), aged 97 (75-130) days and weighing 337.2 (219.6-465.9) g, mean (range).

METHODS

Rats were assigned to one of five BLIS vial groups, in which drug was administered from a newly opened vial or 1, 2, 3 and 4 days after the vial was opened. The vials were refrigerated between uses. A 14 gauge needle attached to an injection plug was used to puncture each vial once and was not removed; BLIS was withdrawn from the injection plug in a multiple-dose fashion. A dose rate of 0.4 mL kg^-1 was administered subcutaneously into the left pelvic limb paw. Antinociception was evaluated using a paw pressure test on both injected and uninjected paws before (time 0, baseline) and 1, 24, 48 and 72 hours after injection.

RESULTS

Age of BLIS vial had no significant effect on anesthetic efficacy (p = 0.97). Across all groups, paw withdrawal latency averaged 5.23 ± 0.24 seconds at baseline (before BLIS injection), increased to 16.45 ± 0.65 seconds at 1 hour after BLIS injection, declined to 7.50 ± 0.76 seconds at 24 hours after BLIS injection, and further declined thereafter (p < 0.001). There was no significant change in paw withdrawal latency in the uninjected paw over time.

CONCLUSIONS AND CLINICAL RELEVANCE

BLIS single-use vials retained efficacy when used up to 5 days in a multiple-dose fashion. Because anesthetic effects declined substantially after 24 hours, multimodal pain management remains important for providing analgesia care.

Efficacy of liposomal bupivacaine in spine surgery: a systematic review

BACKGROUND CONTEXT

Spine surgery with posterior approaches may involve extensive manipulation of native structures, resulting in significant postoperative pain. Liposomal bupivacaine (LB) is an injectable analgesic that has demonstrated efficacy in decreasing postoperative pain and opioid requirements in patients across multiple surgical subspecialties.

PURPOSE

To consolidate and analyze the findings of retrospective cohort-matched studies and prospective randomized controlled trials investigating the use of LB in spine surgery.

STUDY DESIGN

A systematic review.

STUDY SAMPLE

Retrospective cohort-matched studies and randomized controlled trials (RCTs) investigating the efficacy of injected LB in spinal surgery compared with a control/no treatment group.

METHODS

MEDLINE, Cochrane controlled trials register, and Google Scholar were searched to identify all studies that examined the effect of LB use on outcomes in spine surgery. Our search identified 10 articles that independently evaluated the effect of LB on reduction of postoperative opioid use, pain scores, hospital length of stay, cost, and incidence of adverse effects. The principles of GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) were applied to assess the quality of evidence from each study.

RESULTS

Ten studies were analyzed (1,112 total patients). LB was associated with significantly lower millimolar morphine equivalents (MME) of postoperative opioids, especially in opiate-tolerant patients, visual analog scale (VAS) scores, area under the curve (AUC) of cumulative pain scores, numeric pain scale scores, and hospital length of stay (LOS), with comparable or lower odds of adverse effects relative to controls.

CONCLUSIONS

Low-quality evidence suggests that liposomal bupivacaine may safely decrease postoperative opioid requirements, pain scores, and length of stay in patients undergoing spine surgery, whereas moderate-quality evidence does not support its use at this time. Therefore, additional standardized well-powered prospective studies are necessary to more clearly assess the efficacy of LB in spine surgery.

Apophenia and anesthesia: how we sometimes change our practice prematurely

Human beings are predisposed to identifying false patterns in statistical noise, a likely survival advantage during our evolutionary development. Moreover, humans seem to prefer "positive" results over "negative" ones. These two cognitive features lay a framework for premature adoption of falsely positive studies. Added to this predisposition is the tendency of journals to "overbid" for exciting or newsworthy manuscripts, incentives in both the academic and publishing industries that value change over truth and scientific rigour, and a growing dependence on complex statistical techniques that some reviewers do not understand. The purpose of this article is to describe the underlying causes of premature adoption and provide recommendations that may improve the quality of published science.

Perioperative Pain Management in Ambulatory and Inpatient Shoulder Surgery

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Acetaminophen is an effective addition to a multimodal pain regimen; however, evidence to support intravenous versus oral administration requires further evaluation.

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While nonsteroidal anti-inflammatory drugs are a valuable addition to a multimodal pain strategy, concerns regarding their effect on healing after certain procedures (i.e., rotator cuff repair) in select patients may preclude their use.

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The use of perioperative gabapentinoids have varied results for pain control, and additional research is warranted to support their use after certain shoulder procedures.

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Opioid-prescribing should be limited and reserved for severe postoperative pain. When prescribed, opioids should be taken at the lowest possible dose and for the shortest period.

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Centrally acting analgesics such as tramadol have been shown to be as effective as opioids and have a lower risk of complications.

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Nerve blocks are an excellent addition to multimodal pain management strategies. Longer-lasting formulations of perioperative single-shot injections and indwelling catheters may reduce rebound pain.

Opioid-Free Recovery from Bunionectomy with HTX-011, a Dual-Acting Local Anesthetic Combining Bupivacaine and Meloxicam, as the Foundation of Non-Opioid Multimodal Analgesia

BACKGROUND

There is a need for postoperative pain control that minimizes or eliminates opioid use during the first 72 hours following surgery, when pain is most severe. HTX-011 is an extended-release, dual-acting local anesthetic that demonstrated superior 72-hour analgesia over standard of care bupivacaine hydrochloride (HCl) and saline placebo in a phase 3 bunionectomy study (EPOCH-1). Having shown HTX-011 monotherapy is superior to bupivacaine HCl in reducing postoperative pain intensity and opioid use, this follow-on study evaluated the safety and efficacy of HTX-011 as the foundation of a multimodal analgesia (MMA) regimen using over-the-counter medications recommended by practice guidelines for pain management.

METHODS

Following regional anesthesia administered as a lidocaine block, patients underwent unilateral bunionectomy with osteotomy and internal fixation. Prior to closure, HTX-011 (up to 60 mg bupivacaine/1.8 mg meloxicam) was applied without a needle. Patients received scheduled postoperative MMA alternating ibuprofen (600 mg) and acetaminophen (1 g) every 3 hours for 72 hours. Efficacy was assessed based on pain intensity (numeric rating scale [NRS; 0-10]) and consumption of opioid rescue medication (intravenous morphine milligram equivalents [MME]). Adverse event and vital sign monitoring, plus laboratory and wound healing assessments, were used to determine safety.

RESULTS

Over the 72-hour assessment period following bunionectomy, mean pain scores were mild in severity (NRS <4) and 22/31 patients (71%) experienced no severe pain (NRS ≥7) with HTX-011 as the foundation of scheduled, non-opioid MMA. Patients consumed an average of 1.61 MME total, with 24/31 (77%) requiring no opioid rescue medication (opioid-free). HTX-011 was well-tolerated and demonstrated no safety concerns with the inclusion of postoperative MMA.

CONCLUSIONS

HTX-011 as the foundation of an MMA regimen including scheduled ibuprofen and acetaminophen maintained mean postoperative pain scores in the mild range and enabled opioid-free recovery for 77% of bunionectomy patients through the 28-day recovery period.

Nanotherapeutic-directed approaches to analgesia

The ongoing opioid crisis highlighted the need for non-steroidal anti-inflammatory drugs (NSAIDs), nonaddictive analgesics against pain, fever, and inflammation. However, NSAIDs may cause gastrointestinal and cardiovascular adverse effects. To avoid systemic toxicity and deliver drugs to diseased tissues, nanotechnology methods of NSAID encapsulation have been reported and some have reached clinical development. Currently, 57 micro- and nanodrugs are approved by the US FDA. Already approved nanoanalgesics have revealed superior efficacy or reduced toxicity compared with placebo or lower doses of systemically administered active comparators. In this review, the evidence for approval of the marketed nanodrugs will be discussed, with a focus on therapies for pain and inflammation. Nanomedicine remains an attractive field for the development of targeted analgesics.

The Efficacy of Liposomal Bupivacaine for Opioid and Pain Reduction: A Systematic Review of Randomized Clinical Trials

Background The opioid crisis has prompted surgeons to search for alternative postoperative methods of analgesia. Liposomal bupivacaine is a long-acting local anesthetic formulation used for pain, potentially reducing opioid use. Evaluation of liposomal bupivacaine as a viable alternative for pain management is needed. The objective was to assess the efficacy of randomized clinical trials (RCTs) of liposomal bupivacaine in postoperative pain management and opioid consumption. Material and Methods The authors extracted RCTs comparing liposomal bupivacaine versus placebo or active comparators for postoperative pain or opioid reduction from PubMED/MEDLINE, Cochrane Library, and ClinicalTrials.gov. Exclusion criteria included nonhuman studies, non-RCTs, pooled studies, and inability to access full text. The following variables were abstracted: surgical specialty, number of subjects, pain and opioid outcomes, and authors' financial conflicts of interest. Results We identified 77 published RCTs, of which 63 studies with a total of 6770 subjects met inclusion criteria. Liposomal bupivacaine did not demonstrate significant pain relief compared to placebo or active agents in 74.58% of RCTs. Of the studies evaluating narcotic use, liposomal bupivacaine did not show a reduction in opioid consumption in 85.71% of RCTs. Liposomal bupivacaine, when compared to standard bupivacaine or another active agent, yielded no reduction in opioid use in 83.33% and 100.00% of studies, respectively. Clinical trials with a financial conflict of interest relating to the manufacturer of liposomal bupivacaine were significantly more likely to show pain relief (OR: 14.31 [95% CI, 2.8, 73.10], P = 0.0001) and decreased opioid consumption (OR: 12.35 [95% CI 1.40, 109.07], P = 0.0237). Of the 265 unpublished RCTs on ClinicalTrials.gov, 47.54% were withdrawn, terminated, suspended, or completed without study results available. Conclusions The efficacy of liposomal bupivacaine for providing superior postoperative pain control relative to placebo or another active agent is not supported by a majority of RCTs. Underreporting of trial results and bias due to underlying financial relationships amongst authors are two major concerns that should be considered when evaluating the available evidence.

A novel excisional wound pain model for evaluation of analgesics in rats

Background

Management of pain from open wounds is a growing unmet healthcare need. However, the models available to study pain from wounds or to develop analgesics for the patients suffering from them have primarily relied on incisional models. Here, we present the first characterized and validated model of open wound pain.

Methods

Unilateral full-skin excisional punch biopsy wounds on rat hind paws were evaluated for evoked pain using withdrawal responses to mechanical and thermal stimulation, and spontaneous pain was measured using hind paw weight distribution and guarding behavior. Evaluations were done before wounding (baseline) and 2-96 hours post-wounding. The model was validated by testing the effects of buprenorphine and carprofen.

Results

Pain responses to all tests increased within 2 hours post-wounding and were sustained for at least 4 days. Buprenorphine caused a reversal of all four pain responses at 1 and 4 hours post-treatment compared to 0.9% saline (P < 0.001). Carprofen decreased the pain response to thermal stimulation at 1 (P ≤ 0.049) and 4 hours (P < 0.011) post-treatment compared to 0.9% saline, but not to mechanical stimulation.

Conclusions

This is the first well-characterized and validated model of pain from open wounds and will allow study of the pathophysiology of pain in open wounds and the development of wound-specific analgesics.

Effectiveness of Standard Local Anesthetic Bupivacaine and Liposomal Bupivacaine for Postoperative Pain Control in Patients Undergoing Truncal Incisions: A Randomized Clinical Trial

IMPORTANCE

Liposomal bupivacaine for pain relief is purported to last 3 days compared with 8 hours with standard bupivacaine. However, its effectiveness is unknown in truncal incisions for cardiothoracic or vascular operations.

OBJECTIVE

To compare the effectiveness of single-administration standard bupivacaine vs liposomal bupivacaine in patients undergoing truncal incisions.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial enrolled patients undergoing sternotomy, thoracotomy, minithoracotomy, and laparotomy from a single cardiovascular surgery department in an academic medical center between November 2012 and June 2018. The study was powered to detect a Cohen effect size of 0.35 with a power of greater than 80%. Data analysis was performed from July to December 2018.

INTERVENTION

Patients were randomized to standard bupivacaine or liposomal bupivacaine.

MAIN OUTCOMES AND MEASURES

Pain was assessed over 3 postoperative days by the Numeric Rating Scale (NRS). Adjunctive opioids were converted to morphine equivalents units (MEU). NRS scores were compared using Wilcoxon rank-sum (3-day area under the curve) and 2-way nonparametric mixed models (daily scale score) to assess time-by-group interaction. Secondary outcomes included cumulative opioid consumption.

RESULTS

A total of 280 patients were analyzed, with 140 in each group (single-administration standard bupivacaine vs liposomal bupivacaine). Mean (SD) age was 60.2 (14.4) years, and 101 of 280 patients (36%) were women. Irrespective of treatment assignment, pain decreased by a mean of approximately 1 point per day over 3 days (β = -0.87; SE = 0.11; mixed model regression P < .001). Incision type was associated with pain with patients undergoing thoracotomy (including minithoracotomy) reporting highest median (interquartile range [IQR]) pain scores on postoperative days 1 (liposomal vs standard bupivacaine, 6 [4-8] vs 5 [3-7]; P = .049, Wilcoxon rank-sum) and 2 (liposomal vs standard bupivacaine, 5 [4-7] vs 4 [2-6]; P = .003, Wilcoxon rank-sum) but not day 3 (liposomal vs standard bupivacaine, 3 [2-6] vs 3 [1-5]; P = .10, Wilcoxon rank-sum), irrespective of treatment group. Median (IQR) 3-day cumulative NRS was 12.0 (8.0-16.5) for bupivacaine and 13.5 (9.0-17.0) for liposomal bupivacaine (P = .15, Wilcoxon rank-sum) Furthermore, use of opioids was greater following liposomal bupivacaine compared with standard bupivacaine (median [IQR], 41.5 [21.3-73.8] MEU vs 33.0 [17.8-62.5] MEU; P = .03, Wilcoxon rank-sum). On multivariable analysis, no interaction by incision type was observed for mean pain scores or opioid use.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial involving truncal incisions for cardiovascular procedures, liposomal bupivacaine did not provide improved pain control and did not reduce adjunctive opioid use compared with conventional bupivacaine formulation over 3 postoperative days.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02111746.

Liposomal bupivacaine interscalene nerve block in shoulder arthroplasty is not superior to plain bupivacaine: a double-blinded prospective randomized control trial

BACKGROUND

Interscalene brachial plexus blocks are a common modality used to provide adjunctive pain relief with shoulder replacement surgery. In 2018, the Federal Drug Administration approved the use of liposomal bupivacaine (LB) for such nerve blocks. We sought to evaluate whether this formulation of bupivacaine would provide superior pain relief for shoulder replacement patients over standard bupivacaine alone. Our hypotheses were that in the LB cohort the average postoperative pain score over the first 72 hours would be significantly lower, time to block cessation would be longer, total opioid consumption would be lower, and the average patient satisfaction score regarding their pain management would be higher.

MATERIALS AND METHODS

A randomized, double-blinded study was designed comparing primary shoulder replacement surgery after an interscalene block with 25 mL of 0.5% plain bupivacaine vs. 133 mg of LB with 7.5 mL of 0.5% and 7.5 mL of 0.25% plain bupivacaine. A total of 104 patients were included in the study, with an equal number in each study arm. Patients' visual analog pain scores (VAPS) were followed for their inpatient stay, first 3 full outpatient days, and at a 3-week follow-up. Use of opioid medication was recorded for the same intervals and converted to morphine milligram equivalents. The time to first opioid rescue was documented, as well as the patients' satisfaction with their pain management at both the 3-day and 3-week intervals.

RESULTS

No clinically relevant advantage to the use of LB over plain bupivacaine was found. During the second postoperative day, the mean VAPS was 2.4 with LB vs. 3.3 in the standard cohort (P = .0409). The only other statistically significant finding was a higher VAPS with LB during the third full day home compared with standard bupivacaine (4.0 vs. 2.8, respectively, P = .0197). Both of these differences were less than the minimal clinically important difference of 2 for the VAPS. Analysis of the VAPS for the first and third postoperative days, the first and second full days home, and at 3 weeks revealed no significant difference. Similarly, there was no significant difference in time to first opioid rescue, total morphine milligram equivalent use, and patient satisfaction with pain management.

CONCLUSION

When used for an interscalene block to provide adjunctive pain relief in shoulder replacement surgery, the addition of LB to plain bupivacaine provides no additional clinically important benefit to the patient's pain experience over standard bupivacaine.

Clinical Effectiveness of Liposomal Bupivacaine Administered by Infiltration or Peripheral Nerve Block to Treat Postoperative Pain

The authors provide a comprehensive summary of all randomized, controlled trials (n = 76) involving the clinical administration of liposomal bupivacaine (Exparel; Pacira Pharmaceuticals, USA) to control postoperative pain that are currently published. When infiltrated surgically and compared with unencapsulated bupivacaine or ropivacaine, only 11% of trials (4 of 36) reported a clinically relevant and statistically significant improvement in the primary outcome favoring liposomal bupivacaine. Ninety-two percent of trials (11 of 12) suggested a peripheral nerve block with unencapsulated bupivacaine provides superior analgesia to infiltrated liposomal bupivacaine. Results were mixed for the 16 trials comparing liposomal and unencapsulated bupivacaine, both within peripheral nerve blocks. Overall, of the trials deemed at high risk for bias, 84% (16 of 19) reported statistically significant differences for their primary outcome measure(s) compared with only 14% (4 of 28) of those with a low risk of bias. The preponderance of evidence fails to support the routine use of liposomal bupivacaine over standard local anesthetics.

Liposomal Bupivacaine Infiltration After Median Sternotomy in Pediatric Cardiac Surgery

OBJECTIVE

The present study retrospectively ascertained whether liposomal bupivacaine (LB) injected subcutaneously after median sternotomy incisions in pediatric cardiac surgery patients is as efficacious as the ON-Q PainBuster pump (ON-Q) (Avonas Medical, Alpharetta, GA).

DESIGN

Retrospective cohort comparison.

SETTING

Pediatric hospital.

PARTICIPANTS

Cardiac surgery patients who were treated with LB for elective cardiac surgery.

INTERVENTIONS

Patients received 4 mg/kg of LB admixed with 0.25% bupivacaine and 0.9% normal saline. These patients were compared with an age- and procedure-matched control group of similar size treated with the ON-Q pump (continuous infusion 0.25% bupivacaine via subcutaneous catheter). Total analgesics used and route, other analgesics or sedatives, and pain scores (first 24 hours and cumulative) were tracked for 96 hours after surgery.

MEASUREMENTS AND MAIN RESULTS

A total of 222 patients were equally divided between the two groups. Overall, the median (interquartile range) age was 6.5 (3.8-12.7) years. Unadjusted analysis suggested that patients in the LB group were administered a significantly higher dose of intravenous acetaminophen (77.4 v 60.0 mg/kg; p < 0.05). Extubation in the operating room was significantly higher in the LB patients (p < 0.05). Narcotic (morphine) administration was significantly higher in the ON-Q group (100.0% v 95.5%; p < 0.05). Although the median pain score within the first 24 hours was higher in LB patients (27.0 v 17.0; p < 0.05), there was a significantly greater difference observed in the Numeric Rating Scale area under the curve for the ON-Q group.

CONCLUSIONS

LB is at least as effective as the ON-Q is for providing analgesia after median sternotomy incision in children.

Effect of Liposomal Bupivacaine on Postoperative Opioid Requirements for Total Hip Arthroplasty, Total Knee Arthroplasty, Laminectomy, Hysterectomy, and Abdominoplasty Procedures

Purpose: Opioid use postoperatively has been linked to adverse events and an increase in opioid dependency. This retrospective study evaluated the effect of using liposomal bupivacaine (LB) for postoperative pain control on total opioid consumption, pain control, serious opioid-related adverse events (ORAEs), and hospital length of stay (LOS) in total knee arthroplasty (TKA), total hip arthroplasty (THA), laminectomy, hysterectomy, and abdominoplasty procedures when compared with a control group. Methods: Patients receiving LB from August 1, 2017, to February 1, 2018, for the aforementioned procedures were included for evaluation, and patients undergoing similar procedures who did not receive LB served as the control group. The principal outcome was opioid consumption through postoperative day 5 or discharge, whichever came first, assessed by morphine milligram equivalents (MMEs). Secondary outcomes included pain scores within 72 hours postoperation, hospital LOS, and serious ORAEs. Results: A total of 323 patients were identified for inclusion in the study: TKA, n = 144; THA, n = 48; laminectomy, n = 73; hysterectomy, n = 30; and abdominoplasty, n = 28. Liposomal bupivacaine use was associated with reduced postoperative opioid consumption compared with alternative therapies with a median 71 MME (25%-75%; interquartile range [IQR] = 32.5-148.5) versus 102 MME (25%-75%; IQR = 57-165), P < .005. However, higher numeric pain scores were reported in the LB group compared with the control group for postoperative day 0 with a median of 5.5 (25%-75%; IQR = 4.5-7.4) versus 5.5 (25%-75%; IQR = 4-7) in the control group ( P < .001) and on postoperative day 1 with a median of 6 (25%-75%; IQR = 4.5-7) versus 5.5 (25%-75%; IQR = 4.3-7), P < .001. There was no difference in hospital LOS or ORAEs. Conclusion: In this retrospective analysis of pain management after TKA, THA, laminectomy, hysterectomy, and abdominoplasty procedures, patients receiving LB consumed significantly less opioid medications. However, this was not associated with clinically meaningful improvements in pain scores, hospital LOS, or serious ORAEs.

Long-acting liposomal bupivacaine and postoperative opioid use after Peyronie's disease surgery: a pilot study

Background

Novel strategies have been proposed to minimize postoperative opioid use, yet many patients experience significant pain after penile surgery. Our objective was to evaluate postoperative opioid use in patients undergoing penile ring block with long-acting liposomal bupivacaine (LB; Exparel) during surgery for Peyronie's disease (PD).

Methods

We identified patients who underwent tunica albuginea plication (TAP) and plaque excision/grafting (PEG) for PD between July 2019 and September 2020. Intraoperatively, a ring block was administered at the penile base penis with 20 cc of LB. Patients were instructed to use over the counter pain medications as first line treatment for postoperative pain, and opioids were available for severe breakthrough pain as needed [7.5 oral morphine equivalents (OME) =5 mg oxycodone]. Opioid use was assessed during the first five days postoperatively.

Results

In total, 28 patients met inclusion criteria including 18/28 (64%) who underwent TAP and 10/28 (36%) who underwent PEG. Median patient age was 56 years (IGR 51;61). Median postoperative 10-point visual analogue pain score was 0 (range 0-3). Duration of penile anesthesia ranged from 1.5-4 days. In total, 9/28 patients (32%) utilized opioids during the first five days postoperatively (range 7.5-75 OME). Two patients (7%) required opioids during the first two days after surgery. 27/28 (96%) were satisfied or highly satisfied with postoperative pain control.

Conclusions

Intraoperative penile ring block with LB resulted in excellent pain control with local anesthetic duration of 1.5-4 days. The majority of patients did not require any opioids during the early postoperative period. Further study comparing outcomes with shorter-acting local anesthetics is necessary to balance pain control benefits with additional cost.

Bupivacaine local anesthetic to decrease opioid requirements after radical cystectomy: Does formulation matter?

INTRODUCTION

Reduction of opioids is an important goal in the care of patients undergoing radical cystectomy (RC). Liposomal bupivacaine (LB) has been shown to be a safe and effective pain reliever in the immediate postoperative period and has been reported to reduce postoperative opioid requirements. Since the liposomal formulation is predicated on slow systemic absorption, the amount of bupivacaine administered is notably higher than that typically used with standard bupivacaine (SB) formulations. In addition, LB is costly, not universally available, and studies comparing this formulation to SB are lacking. We sought to determine if there is a difference in postoperative opioid requirements in patients who receive LB vs. high dose SB at the time of RC.

METHODS

In May 2019 we transitioned to administration of high-volume SB injected intraoperatively at the time of RC. This prospective cohort was compared to a historical cohort of patients who received injection of LB at the time of surgery. Primary endpoints included postsurgical opioid use measured in morphine equivalent dose (MED) and patient-reported Numeric Rating Scale (NRS) pain scores and length of stay. All patients were managed using principles of enhanced recovery after surgery (ERAS).

RESULTS

From May 2019 through August 2019, 28 patients underwent RC and met eligibility criteria to receive SB at the time of surgery. They were compared to a historical cohort of 34 patients who received LB between November 2017 and July 2018. There was no difference in MED exposure either in the postanesthesia care unit (SB 9.0 ± 8.9 MED vs. LB 6.5 ± 9.4 MED, P= 0.29) or during the remainder of the hospital stay (SB 36.8 ± 56.9 MED vs. LB 42.1 ± 102.5 MED, P= 0.81), no difference in NRS pain scores on postoperative day 1 (SB 2.6 ± 1.6 vs. LB 2.1 ± 1.7, P= 0.23), day 2 (SB 2.4 ± 1.8 vs. LB 1.9 ± 1.6, P= 0.19), or day 3 (SB 1.9 ± 1.8 vs. LB 1.7 ± 1.7, P= 0.69) and no difference in length of stay (SB 5.0 ± 1.7 days, LB 4.9 ± 3.3 days, P= 0.93). Subgroup analysis of open RC and robotic-assisted RC showed no significant difference in MED or pain scores between LB and SB patients.

CONCLUSIONS

Among patients undergoing RC under ERAS protocol there was no significant difference in postoperative opioid consumption, NRS pain scores, or length of stay among patients receiving SB compared to LB.

Liposomal Bupivacaine Versus Bupivacaine Hydrochloride for Intercostal Nerve Blockade in Minimally Invasive Thoracic Surgery

OBJECTIVES

The objective of this study was to compare the effects of liposomal bupivacaine (Lipo-B) and bupivacaine hydrochloride (B-HCl), in the presence of multimodal analgesia, on postoperative analgesia and opioid consumption in minimally invasive thoracic surgery (MITS) lobectomy.

DESIGN

Retrospective observational cohort study.

SETTING

Tertiary care cancer center.

PARTICIPANTS

A total of 60 patients who underwent MITS lobectomy and received intercostal nerve blockade (ICNB) with either 0.66% Lipo-B (n = 29) or 0.5% B-HCl (n = 31).

INTERVENTIONS

All patients received intravenous patient-controlled analgesia for the first 12 hours postoperatively, followed by opioids and nonsteroidal anti-inflammatory drugs as needed.

MEASUREMENTS AND MAIN RESULTS

Perioperative opioid and nonopioid consumption and pain scores were compared between groups at 12-hour intervals for the first 72 hours. Between the two groups, there were no statistically significant differences in demographic characteristics, intraoperative (p = 0.46) and postoperative opioid consumption, Richmond Agitation-Sedation Scale scores and pain scores upon postanesthesia care unit arrival and after four hours, length of postanesthesia care unit stay (p = 0.84), or length of hospital stay (p = 0.55). Both groups received intra- and postoperative multimodal analgesia.

CONCLUSIONS

In this cohort, no differences in opioid consumption or pain scores were observed in the immediate postoperative period following MITS lobectomy between patients given ICNB with Lipo-B and those given ICNB with B-HCl in the presence of multimodal analgesia.

Which is the best analgesia treatment for total knee arthroplasty: Adductor canal block, periarticular infiltration, or liposomal bupivacaine? A network meta-analysis

STUDY OBJECTIVE

To review all randomized controlled trials (RCTs) comparing the analgesic efficacy of adductor canal block (ACB), periarticular infiltration (PAI), and any other mode of these treatments in analgesia, such as PAI with liposomal bupivacaine (LB), continuous adductor canal block (cACB) or ACB + PAI, after total knee arthroplasty (TKA).

DESIGN

Systematic review and network meta-analysis of RCTs.

PATIENTS

We searched PubMed, Embase, and the Cochrane database to detect all relevant RCTs on investigating the analgesic effects of ACB, PAI and LB for TKA published until April 2020.

INTERVENTIONS

Use of different analgesic methods of ACB, PAI, cACB, ACB + PAI and LB.

MEASUREMENTS

The primary endpoint was visual analog scale (VAS) score at rest and movement. The secondary endpoints were opioids consumption, length of hospitalization and knee range of motion (ROM). We used Cochrane risk of bias to assess the quality of evidence for outcomes.

RESULTS

Forty-two studies involving 3785 patients with 5 different methods containing ACB, PAI, ACB + PAI, continuous ACB (cACB), LB, were evaluated. According to surface under the cumulative ranking curve value, 24 h resting VAS score was the lowest the ACB + PAI (88.4%), followed by cACB (73.4%); Resting VAS score at 48 h and movement VAS score at 24 h and 48 h was the lowest in the cACB (99.9%, 92% and 100%). Total opioids consumption was the least in LB (81.4%) before cACB (60.8%). ROM was the largest in the ACB + PAI (84.1%) before cACB (78.8%).

CONCLUSION

Although all analgesic methods available were not evaluated, and further studies are needed to establish our results, the 24 h resting VAS score was lowest in ACB + PAI and 48 h resting and movement VAS score was lowest in cACB.

CLINICAL TRIAL REGISTRATION

PROSPERO (CRD 42020168102).

Entrapping bupivacaine-loaded emulsions in a crosslinked-hydrogel increases anesthetic effect and duration in a rat sciatic nerve block model

The purpose of this research was to evaluate a novel long-acting bupivacaine delivery system for control of postoperative pain. Bupivacaine-loaded lipid emulsion (BLE) droplets were created by high-speed homogenization. The BLE droplets were then entrapped into a crosslinked-hyaluronic acid hydrogel system to create an injectable composite gel formulation (HA-BLE). Dynamic light scattering, rheological, and drug release techniques were used to characterize the formulations. A rat sciatic nerve block with a thermal nociceptive assay was used to evaluate the anesthetic effect in comparison to controls, bupivacaine HCl and liposomal bupivacaine. The BLE droplets had a zeta potential, droplet size, and polydispersity index of -40.8 ± 0.66 mV, 299 ± 1.77 nm, and 0.409 ± 0.037, respectively. The HA-BLE formulation could be injected through 25 g needles and had an elastic modulus of 372 ± 23.7 Pa. Approximately 80% and 100% of bupivacaine was released from the BLE and HA-BLE formulations by 20 and 68 h, respectively. The HA-BLE formulation had a 5-times greater anesthetic area under the curve and an anesthetic duration that was twice as long as controls. Results indicate that incorporating the BLEs into the hydrogel significantly increased anesthetic effect by protecting the BLE droplets from the in vivo environment.

Intramuscular Liposomal Bupivacaine Decreases Length of Stay and Opioid Usage Following Lumbar Spinal Fusion

STUDY DESIGN

A retrospective cohort review.

OBJECTIVES

The objective of this study was to investigate the efficacy of liposomal bupivacaine (LB) in patients undergoing lumbar spinal fusion.

SUMMARY OF BACKGROUND DATA

Historically, posterior spinal fusion has been recognized as a particularly painful surgery. Postoperative pain limits early patient mobilization and discharge, and negatively impacts patient satisfaction. Local infiltration of anesthetic agents combined with postoperative multimodal pain management is common. On the basis of existing data, the liposomal formulation of bupivacaine might play a role in promoting faster recovery during the immediate postoperative period. The purpose of this study was to investigate the potential impact of LB on postoperative opioid requirements, ambulation, and duration of hospital stay, as well as potential health care cost savings.

MATERIALS AND METHODS

A historical cohort of adult lumbar spinal fusion patients was retrospectively evaluated, in which 105 patients received nonliposomal anesthetic and 105 received LB. Both groups were managed with a standardized postoperative analgesia regimen. Demographic information, opioid consumption, length of stay, distance ambulated, and total cost of inpatient stay were collected.

RESULTS

Although there was no difference in the pain scores between the 2 groups, the LB group was associated with significantly lower opioid usage throughout the postoperative period. More patients in the LB group were discharged within 2 days of surgery compared with the control group (88.6% vs. 38.1%, P<0.05). The control group was able to walk for a longer median distances (175 vs. 150 ft, P=0.02) on the first attempt, however, a significantly larger proportion of the LB group walked within the first 12 hours after surgery (61% vs. 3%, P<0.001). Also, LB usage was associated with $218 higher pharmacological cost compared with the control group but an overall $3035 lower cost for the entire hospitalization (P<0.001).

CONCLUSION

Adjunctive usage of LB with lumbar fusion surgeries promotes earlier mobility, lower opioid consumption, and shorter length of stay resulting in overall lower health care cost.

LEVEL OF EVIDENCE

Level III.

Epicardial Interventions: Impact of Liposomal Bupivacaine on Postprocedural Management (The EPI-LIBRE Study)

Background:

Electrophysiological procedures such as epicardial ventricular tachycardia ablation and Lariat left atrial appendage ligation that involve the epicardial space are typically associated with significant postoperative pain due to mechanical irritation and associated inflammation. There is an unmet need for an effective pain management strategy in this group of patients. We studied how this impacts patient comfort and duration of hospitalization and other associated comorbidities related to pericardial access.

Methods:

This is a multicenter retrospective study including 104 patients who underwent epicardial ventricular tachycardia ablation and Lariat left atrial appendage exclusion. We compared 53 patients who received postprocedural intrapericardial liposomal bupivacaine (LB)+oral colchicine (LB group) and 51 patients who received colchicine alone (non-LB group) between January 2015 and March 2018.

Results:

LB was associated with significant lowering of median pain scale at 6 hours (1.0 [0–2.0] versus 8.0 [6.0–8.0], P <0.001), 12 hours (1.0 [1.0–2.0] versus 6.0 [5.0–6.0], P <0.001), and up to 48 hours postprocedure. Incidence of acute severe pericarditis delayed pericardial effusion and gastrointestinal adverse effects were similar in both groups. Median length of stay was significantly lower in LB group (2.0 versus 3.0; adjusted linear coefficient −1 [CI −1.3 to −0.6], P <0.001). Subgroup analysis demonstrated similar favorable outcomes in both Lariat and epicardial ventricular tachycardia ablation groups.

Conclusions:

Addition of intrapericardial postprocedural LB to oral colchicine in patients undergoing epicardial access during ventricular tachycardia ablation or Lariat procedure is associated with significantly decreased numeric pain score up to 48 hours compared with colchicine alone. It is also associated with significantly shorter length of hospital stay without an increase in the risk of adverse events.

PROSPECT guideline for hallux valgus repair surgery: a systematic review and procedure-specific postoperative pain management recommendations

Hallux valgus repair is associated with moderate-to-severe postoperative pain. The aim of this systematic review was to assess the available literature and develop recommendations for optimal pain management after hallux valgus repair. A systematic review using PROcedure SPECific Postoperative Pain ManagemenT (PROSPECT) methodology was undertaken. Randomized controlled trials (RCTs) published in the English language from inception of database to December 2019 assessing postoperative pain using analgesic, anesthetic, and surgical interventions were identified from MEDLINE, EMBASE, and Cochrane Database, among others. Of the 836 RCTs identified, 55 RCTs and 1 systematic review met our inclusion criteria. Interventions that improved postoperative pain relief included paracetamol and non-steroidal anti-inflammatory drugs or cyclo-oxygenase-2 selective inhibitors, systemic steroids, ankle block, and local anesthetic wound infiltration. Insufficient evidence was found for the use of gabapentinoids or wound infiltration with extended release bupivacaine or dexamethasone. Conflicting evidence was found for percutaneous chevron osteotomy. No evidence was found for homeopathic preparation, continuous local anesthetic wound infusion, clonidine and fentanyl as sciatic perineural adjuncts, bioabsorbable magnesium screws, and plaster slippers. No studies of sciatic nerve block met the inclusion criteria for PROSPECT methodology due to a wider scope of included surgical procedures or the lack of a control (no block) group. The analgesic regimen for hallux valgus repair should include, in the absence of contraindication, paracetamol and a non-steroidal anti-inflammatory drug or cyclo-oxygenase-2 selective inhibitor administered preoperatively or intraoperatively and continued postoperatively, along with systemic steroids, and postoperative opioids for rescue analgesia.

Bupivacaine Extended-Release Liposomal Injection Versus Bupivacaine HCl for Early Postoperative Pain Control Following Wrist Operations: A Prospective, Randomized Control Trial

PURPOSE

This study evaluated pain control after wrist operations using a long-acting local anesthetic, liposomal bupivacaine, compared with the standard local anesthetic, bupivacaine HCl.

METHODS

Patients undergoing elective carpometacarpal joint arthroplasty and proximal row carpectomy were eligible. Those meeting inclusion criteria were enrolled before surgery and were randomized to receive an intraoperative injection of liposomal bupivacaine or bupivacaine HCl. Primary outcomes included intraoperative and postoperative opioid requirements and pain levels. On the first 4 postoperative days, phone contact assessed pain level by numeric rating scale, number of opioids taken in each 24-hour period, and efficacy of anesthesia and opioid side effects with overall benefit of analgesia score.

RESULTS

Postoperative pain scores for 52 patients measured by numeric rating scale demonstrated that liposomal bupivacaine and bupivacaine HCl were similar for pain control. Pain scores and opioid use were similar during the first 4 postoperative days. Opioid use on day 1 was slightly lower with liposomal bupivacaine. There were no statistically significant differences in any postoperative outcome between groups.

CONCLUSIONS

Liposomal bupivacaine and bupivacaine HCl have similar effects in the treatment of early postoperative pain after trapeziometacarpal suspension arthroplasty and proximal row carpectomy. Neither drug demonstrated a clear advantage in this study.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Efficacy of local infiltration anesthesia versus interscalene nerve blockade for total shoulder arthroplasty

Background

Optimal modalities for pain control in shoulder arthroplasty are not yet established. Although regional nerve blockade has been a well-accepted modality, complications and rebound pain have led some surgeons to seek other pain control modalities. Local injection of anesthetics has recently gained popularity in joint arthroplasty. The purpose of this study was to evaluate the effectiveness and complication rate of a low-cost local anesthetic injection mixture for use in total shoulder arthroplasty (TSA) compared with interscalene brachial plexus blockade.

Methods

A total of 314 patients underwent TSA and were administered general anesthesia with either a local injection mixture (local infiltration anesthesia [LIA], n = 161) or peripheral nerve block (PNB, n = 144). Patient charts were retrospectively reviewed for postoperative pain scores, 24-hour opioid consumption, and 90-day postoperative complications.

Results

Immediate postoperative pain scores were not significantly different between groups (P = .94). The LIA group demonstrated a trend toward lower pain scores at 24 hours postoperatively (P = .10). Opioid consumption during the first 24 hours following surgery was significantly reduced in the LIA group compared with the PNB group (P < .0001). There was a trend toward fewer postoperative nerve and cardiopulmonary complications in the LIA group than the PNB group (P = .22 and P = .40, respectively)

Conclusion

Periarticular local injection mixtures provide comparable pain control to regional nerve blocks while reducing opioid use and postoperative complications following TSA. Local injection of a multimodal anesthetic solution is a viable option for pain management in TSA.

Liposomial Bupivacaine for Postoperative Pain Control in Fragility Intertrochanteric Hip Fractures

OBJECTIVES

To determine whether intraoperative liposomal bupivacaine reduces postoperative opioid requirements, pain scores, and length of stay (LOS) in patients with fragility intertrochanteric femur fractures in comparison with a group of patients who did not receive liposomal bupivacaine.

DESIGN

Retrospective observational study.

SETTING

Two academic medical centers.

PATIENTS

One hundred two patients with intertrochanteric hip fracture treated with a cephalomedullary nail implant.

INTERVENTION

Nonrandomized administration of liposomal bupivacaine in 2 cohorts of patients with similar injuries and treatment.

MAIN OUTCOME MEASUREMENTS

Postoperative oral average morphine equivalents (MME) and average numerical pain rating score (NRS). Secondary endpoints included postoperative LOS, operative time, and home discharge.

RESULTS

Forty-six patients received intraoperative liposomal bupivacaine and 56 patients did not. There was no significant difference between age, sex, and American Society of Anesthesiologist level between groups (P > 0.05). The liposomal bupivacaine group received significantly less MME (0.34 vs. 0.92 mg/h/kg, P = 0.04) and had significantly lower NRS (2.89 vs. 5.13, P = 0.04) in the first 24 hours after surgery. MME (1.18 vs. 1.37 mg/h/kg, P = 0.27) and NRS (3.61 vs. 5.51, P = 0.34) were similar at the 36-hour mark. The liposomal bupivacaine group had similar LOS (3.2 days vs. 3.8, P = 0.08), more home discharges (7 vs. 2, P = 0.001), and longer operative time (73.4 vs. 67.2 minutes, P = 0.004).

CONCLUSIONS

Intraoperative liposomal bupivacaine use reduced opioid use and postoperative pain for the first 24 hours after fixation of intertrochanteric femur fractures. Significant increases in likelihood of discharge to home may present an opportunity for cost savings.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Intraoperative Intracavernosal Liposomal Bupivacaine (Exparel) Injection Does Not Affect Systemic Hemodynamics

INTRODUCTION

The systemic effect of intracavernosal liposomal bupivacaine (Exparel) injection during inflatable penile prosthesis (IPP) implantation on systemic hemodynamics has not been clarified.

AIM

To evaluate whether intraoperative intracavernosal Exparel injection affects systemic hemodynamics.

METHODS

We studied 56 consecutive patients who underwent IPP implantation under general anesthesia using the transverse scrotal approach. Exparel [10 mL of 1.3% (13.3 mg/mL)] was instilled bilaterally intracavernosally via a 25-gauge needle around 30 min after starting the surgery. All patients graded their postoperative pain using a standard 10-point scale.

MAIN OUTCOME MEASURE

Perioperative vital signs at defined time intervals and postoperative pain were monitored. The degree of postoperative pain were analyzed using a standard 10-point scale.

RESULTS

Medians and interquartile ranges (IQRs) of the patients' age [64 years (57.3-69.3)], operation time [85 min (78-96)], and estimated blood loss [75 mL (29-100)] were recorded. Although the median preoperative systolic noninvasively measured blood pressure of 131 mm/Hg (IQR: 122-139) fell by 25% to 98 mm/Hg (IQR: 90-100) (P < .001) after anesthesia started, there was no significant decrease in blood pressure between before and after Exparel injection. The perioperative pulse rate and pulse oximetry oxygen saturation were stable. Neither arrhythmia nor convulsion occurred. Patients reported postoperative pain as 0 (IQR: 0-2.25) on a scale of 0-10.

CLINICAL IMPLICATIONS

Intraoperative intracavernosal Exparel injection is safe and effective in patients undergoing IPP implantation surgery.

STRENGTH & LIMITATIONS

This is the first report to describe systemic hemodynamics of intracavernosal Exparel injection. Limitations are lack of blood concentration of Exparel at various time points and long-term follow-up for pain assessment.

CONCLUSION

Although limited by a lack of the blood concentration of Exparel and short follow-up for pain assessment, we concluded that intraoperative intracavernosal Exparel injection does not affect systemic hemodynamics. Taniguchi H, Mulhall JP. Intraoperative Intracavernosal Liposomal Bupivacaine (Exparel) Injection Does Not Affect Systemic Hemodynamics. J Sex Med 2020;17:526-530.

Efficacy of Adductor Canal Block With Liposomal Bupivacaine: A Randomized Prospective Clinical Trial

This study compared the postoperative analgesic efficacy of liposomal bupivacaine as a single-administration adductor canal block (ACB) vs periarticular injection (PAI) for pain control after total knee arthroplasty (TKA). From May 2016 to June 2017, a total of 70 unilateral TKA patients were randomized into 2 groups: PAI (extended-release bupivacaine 266 mg [20-mL vial] with 20 mL of 0.5% bupivacaine hydrochloride and normal saline to a total volume of 120 mL) and ACB (subsartorial saphenous nerve using extended-release bupivacaine 266 mg [20-mL vial]). All patents underwent spinal anesthesia with comprehensive preemptive and postoperative multi-modal pain protocol. All opioids administered were converted to morphine equivalents. Pain was recorded at 4 to 12 hours on the day of surgery, and on postoperative days 1, 2, and 3. Patients and investigators other than the surgeon and anesthesiologist were blinded to the study. The difference in pain scores between the PAI and ACB groups was not statistically significant during the first 12 hours (day 0) after surgery or on postoperative day 1 (5.31 vs 4.26, P=.091). However, on postoperative day 3, the mean pain score increased in the ACB group and decreased in the PAI group (4.8 vs 1.83, P=.037). There was no statistically significant difference between the 2 groups regarding the accumulative daily converted morphine equivalent consumption or total consumption. Although the PAI group demonstrated longer lasting pain relief than the ACB group for the duration of the study, other outcomes were similar between the 2 groups. [Orthopedics. 2020; 43(1):e47-e53.].