Addition of Liposome Bupivacaine to Bupivacaine HCl Versus Bupivacaine HCl Alone for Interscalene Brachial Plexus Block in Patients Having Major Shoulder Surgery:

Future in regional anesthesia and pain medicine: the pharmacological view

Local anesthetics are still incompletely understood, and none of the currently available drugs are optimal. The primary target of local anesthetics is the voltage-gated sodium channel (VGSC), where they lead to a temporary interruption of nerve conduction. Unfortunately, local anesthetics are neither specific at blocking a specific VGSC isoform, nor a specific cell type. We realize now that the old classification of A and C fibers according to myelin thickness is outdated, that next to differing myelin configuration, cells differ also by their molecular biology, and that there are close to 20 different neuronal subgroups when function is concerned. The ideal local anesthetic would only block sensory impulses, or even only painful impulses. In the search for that drug, several research avenues have been followed. First, efforts have been undertaken to extend duration of local anesthetics, by additives or extended-release formulation. Second, blockade of specific pain fibers has been attempted by targeting permanently charged anesthetics specifically into nociceptors. Third, blockade of specific isoforms using antibodies, and adaptation of naturally occurring neurotoxins has shown promise. Lastly, combination of local anesthetics with other analgesics may improve their duration of action.

The Efficacy of Liposomal Bupivacaine On Postoperative Pain Following Abdominal Wall Reconstruction: A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVE

To study the efficacy of liposomal bupivacaine on postoperative opioid requirement and pain following abdominal wall reconstruction.

SUMMARY BACKGROUND DATA

Despite the widespread use of liposomal bupivacaine in transversus abdominis plane block, there is inadequate evidence demonstrating its efficacy in open abdominal wall reconstruction. We hypothesized that liposomal bupivacaine plane block would result in decreased opioid requirements compared to placebo in the first 72 hours after surgery.

METHODS

This was a single-center double-blind, placebo-controlled prospective study conducted between July 2018 and November 2019. Adult patients (at least 18 years of age) undergoing open, elective, ventral hernia repairs with mesh placed in the retromuscular position were enrolled. Patients were randomized to surgeon-performed transversus abdominis plane block with liposomal bupivacaine, simple bupivacaine, or normal saline (placebo). The main outcome was opioid requirements in the first 72 hours after surgery. Secondary outcomes included total inpatient opioid use, pain scores determined using a 100 mm visual analog scale, length of hospital stay, and patient-reported quality of life.

RESULTS

Of the 164 patients that were included in the analysis, 57 patients received liposomal bupivacaine, 55 patients received simple bupivacaine and 52 received placebo. There were no differences in the total opioid used in the first 72 hours after surgery as measured by morphine milligram equivalents when liposomal bupivacaine was compared to simple bupivacaine and placebo (325 ± 225 vs. 350 ± 284 vs. 310 ± 272, respectively, p = 0.725). Similarly, there were no differences in total inpatient opioid use, pain scores, length of stay, and patient-reported quality of life.

CONCLUSIONS

There are no apparent clinical benefits to using liposomal bupivacaine transversus abdominis plane block when compared to simple bupivacaine and placebo for open abdominal wall reconstruction.

Single-Shot Liposomal Bupivacaine Reduces Postoperative Narcotic Use Following Outpatient Rotator Cuff Repair: A Prospective, Double-Blinded, Randomized Controlled Trial

BACKGROUND

Liposomal bupivacaine (LB) theoretically is longer-acting compared with conventional bupivacaine. The purpose of this study was to compare conventional bupivacaine combined with dexamethasone (control group), LB combined with conventional bupivacaine (LB group), and LB combined with dexamethasone and conventional bupivacaine (LBD group) in a perineural interscalene nerve block during ambulatory arthroscopic rotator cuff repair to determine if LB decreased postoperative narcotic consumption and pain. The effect of supplemental dexamethasone on prolonging the analgesic effect of LB was also assessed.

METHODS

This was a prospective, double-blinded, randomized controlled trial of 76 consecutive patients who underwent outpatient arthroscopic rotator cuff repair. Patients were randomized into the 3 interscalene-block treatment groups: control group (n = 26), LB group (n = 24), and LBD group (n = 26). Outcome measures included pain measured with a visual analog scale (VAS; 0 to 10) and narcotic consumption measured in oral morphine milligram equivalents (MME). Both were measured daily on postoperative day 0 through postoperative day 4.

RESULTS

Generalized estimating equation modeling revealed that narcotic consumption across all time points (postoperative days 0 to 4) was significantly lower in the LB group compared with the control group (mean difference, -8.5 MME; 95% confidence interval, -15.4 to -1.6; p = 0.015). Narcotic consumption was significantly higher in the control group on postoperative days 2 and 3 compared with the LB group (p = 0.004 and p = 0.02, respectively) and the LBD group (p = 0.01 and p = 0.003, respectively). There was no difference in narcotic consumption between the LBD and LB groups on any postoperative day. VAS pain scores in all groups were similar across all postoperative days.

CONCLUSIONS

Among patients undergoing outpatient arthroscopic rotator cuff repair, the addition of LB to conventional bupivacaine in interscalene nerve blocks appeared to be effective in controlling postoperative pain. Because LB with and without dexamethasone decreased postoperative narcotic use, LB should be considered for use in preoperative interscalene nerve blocks to reduce the reliance on narcotics for pain management.

LEVEL OF EVIDENCE

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

Perioperative pain management for shoulder surgery: evolving techniques

Improving management of postoperative pain following shoulder surgery is vital for optimizing patient outcomes, length of stay, and decreasing addiction to narcotic medications. Multimodal analgesia (ie, controlling pain via multiple different analgesic methods with differing mechanisms) is an ever-evolving approach to enhancing pain control perioperatively after shoulder surgery. With a variety of options for the shoulder surgeon to turn to, this article succinctly reviews the pros and cons of each approach and proposes a potential pain management algorithm.

Risk factors for complications and return to the emergency department after interscalene block using liposomal bupivacaine for shoulder surgery

BACKGROUND

Exparel (liposomal bupivacaine) has recently gained favor for use in interscalene regional blocks for shoulder surgery. While effective for pain relief, this does have adverse effects that can lead to postoperative emergency department (ED) visits. This study aimed to identify any patient risk factors that are associated with complications leading to ED return visits owing to interscalene blocks using Exparel before shoulder surgery.

METHODS

A retrospective chart review was performed for all patients undergoing shoulder surgery with an Exparel interscalene block in an 8-month period. For each patient, demographic information, comorbidities, type of block, postoperative complications, ED return visits, and readmissions were recorded. The 5-factor modified Frailty Index score and the Charlson Comorbidity Index score were calculated. Univariate and multivariate logistic regressions were conducted to identify risk factors associated with increased complications and return to the ED.

RESULTS

Overall, 352 patients were included; most patients were men, were aged between 51 and 70 years, and had a body mass index of 25.0-35.0. Postoperative complications related to the Exparel interscalene block occurred in 58 patients (16.5%), including 37 minor complications (10.5%) and 21 major complications (6.0%) that led to return ED visits. Univariate analysis yielded American Society of Anesthesiologists (ASA) score (P = .03) as a significant predictor of minor complications. Multivariate logistic regression analysis yielded ASA score (P = .096; odds ratio, 1.64) as trending toward being a significant risk factor for minor complications. Univariate analysis yielded age (P = .006), ASA score (P = .009), and Charlson Comorbidity Index score (P = .002) as significant predictors of major complications. Multivariate logistic regression analysis yielded ASA score (P = .049; odds ratio, 2.25) as the only significant risk factor for major complications.

CONCLUSION

Surgeons and anesthesiologists should strongly consider a patient's ASA score, in addition to his or her pulmonary and cardiac history, when deciding whether the patient is an appropriate candidate for an interscalene regional block using Exparel for shoulder surgery.

Neurotoxicity of bupivacaine and liposome bupivacaine after sciatic nerve block in healthy and streptozotocin-induced diabetic mice

Background

Long-acting local anaesthetics (e.g. bupivacaine hydrochloride) or sustained-release formulations of bupivacaine (e.g. liposomal bupivacaine) may be neurotoxic when applied in the setting of diabetic neuropathy. The aim of the study was to assess neurotoxicity of bupivacaine and liposome bupivacaine in streptozotocin (STZ) - induced diabetic mice after sciatic nerve block. We used the reduction in fibre density and decreased myelination assessed by G-ratio (defined as axon diameter divided by large fibre diameter) as indicators of local anaesthetic neurotoxicity.

Results

Diabetic mice had higher plasma levels of glucose (P < 0.001) and significant differences in the tail flick and plantar test thermal latencies compared to healthy controls (P < 0.001). In both diabetic and nondiabetic mice, sciatic nerve block with 0.25% bupivacaine HCl resulted in a significantly greater G-ratio and an axon diameter compared to nerves treated with 1.3% liposome bupivacaine or saline (0.9% sodium chloride) (P < 0.01). Moreover, sciatic nerve block with 0.25% bupivacaine HCl resulted in lower fibre density and higher large fibre and axon diameters compared to the control (untreated) sciatic nerves in both STZ-induced diabetic (P < 0.05) and nondiabetic mice (P < 0.01). No evidence of acute or chronic inflammation was observed in any of the treatment groups.

Conclusions

In our exploratory study the sciatic nerve block with bupivacaine HCl (7 mg/kg), but not liposome bupivacaine (35 mg/kg) or saline, resulted in histomorphometric indices of neurotoxicity. Histologic findings were similar in diabetic and healthy control mice.

Effect of cocktail therapy after arthroscopic rotator cuff repair: a randomized, double-blind trial

BACKGROUND

We investigated the effectiveness of cocktail therapy after arthroscopic rotator cuff repair (ARCR).

METHODS

We evaluated 128 shoulders undergoing ARCR and used block randomization to divide patients into 2 groups in this double-blind trial: The cocktail group received 20 mL of 0.75% ropivacaine, 5 mg of morphine, 0.3 mg of epinephrine, 2 mg of betamethasone, and saline solution to a total of 42 mL, whereas the control group received 20 mL of 0.75% ropivacaine and saline solution to a total of 42 mL. Postoperatively, one of the drug mixtures was injected into the glenohumeral joint, subacromial bursa, suprascapular nerve, and anterior, middle, and posterior parts of the deltoid muscle according to the treatment group. We recorded patients' visual analog scale scores preoperatively and at 4, 8, 16, 24, and 48 hours postoperatively; the number of patients using postoperative diclofenac suppositories and buprenorphine hydrochloride; the number of patients experiencing nausea; the number of patients with infection and delayed wound healing as adverse effects; the surgery time; the retear rate; and passive shoulder range of motion.

RESULTS

The cocktail group constituted 64 shoulders (50.0%), with 39 men (60.9%) and 25 women (39.1%); the mean age was 64.2 ± 10.2 years. The control group constituted 64 shoulders (50.0%), with 41 men (64.1%) and 23 women (35.9%); the mean age was 65.2 ± 7.5 years. We found no significant difference in age or sex between the 2 groups. There was also no significant difference in rotator cuff tear size or surgery time between the 2 groups. The visual analog scale scores at 8, 16, and 24 hours postoperatively were significantly lower in the cocktail group. The number of patients using suppositories was also significantly lower in the cocktail group. The number of patients receiving buprenorphine injections tended to be lower in the cocktail group, but the difference was not significant. Nausea occurred in 6.3% of patients in the cocktail group and 15.6% in the control group, but the difference was not significant. No infection or delayed wound healing occurred in either group. There was no significant difference in the retear rate between the 2 groups. Passive anterior elevation at 3 months postoperatively was significantly better in the cocktail group than in the control group.

CONCLUSION

We compared cocktail therapy and ropivacaine after ARCR and found no difference in results except for VAS score at 8, 16, and 24 hours postoperatively and frequency of postoperative suppository use without an apparent risk of infection or a detrimental effect on tendon healing.

Perineural dexamethasone attenuates liposomal bupivacaine-induced delayed neural inflammation in mice in vivo

BACKGROUND

Liposomal bupivacaine (Exparel®) is a sustained-release formulation of bupivacaine for use in surgical infiltration anaesthesia. We analysed the histological nerve toxicity and clinical effectiveness of perineural Exparel® alone or with added dexamethasone in a mouse model.

METHODS

We assigned 98 mice receiving a perineural sciatic nerve injection into seven groups: sham (n=14, perineural saline), B (n=14, perineural bupivacaine), BDIP (n=14, perineural bupivacaine + intraperitoneal dexamethasone), BDPN (n=14, perineural bupivacaine + perineural dexamethasone), E (n=14, perineural Exparel®), EDIP (n=14, perineural Exparel® + intraperitoneal dexamethasone), and EDPN (n=14, perineural Exparel® + perineural dexamethasone). The duration of thermoalgesic and motor block was evaluated in 49 mice (seven mice randomly selected by group) every 30 min until recovery. Mice were killed for sciatic nerve histological assessment at 14 or 28 days.

RESULTS

The median duration of motor block was 90, 120, 120, 120, 180, and 180 min and the duration of thermoalgesic block was 240, 300, 360, 360, 360, and 420 min for groups B, BDIP, BDPN, E, EDIP, and EDPN, respectively. The B group mice showed mild neural inflammation at 14 days and the E group mice showed mild neural inflammation at 28 days. Addition (intraperitoneal or perineural) of dexamethasone reduced neural inflammation induced by bupivacaine, whereas only perineural dexamethasone reduced neural inflammation induced by Exparel®.

CONCLUSIONS

Perineural or systemic dexamethasone had a protective effect against the neural inflammation induced by bupivacaine, and perineural dexamethasone attenuated delayed inflammation induced by perineural Exparel®.

Single-shot liposomal bupivacaine interscalene block versus continuous interscalene catheter in total shoulder arthroplasty: Opioid administration, pain scores, and complications

Introduction

We sought to evaluate the efficacy and safety of the liposomal bupivacaine interscalene block (LBB) compared with continuous interscalene catheter block (CISB) in primary shoulder arthroplasty patients.

Methods

A prospective database was retrospectively queried over a 4-year period.

Results

LBB (n = 34) patients had lower opioid consumption and pain scores than CISB (n = 70), especially in opioid naïve patients. LBB patients were discharged with less opioids and had fewer revisits to the emergency department.

Conclusion

Compared with CISB, LBB patients consume fewer opioids, have less pain, are discharged with less opioids, and have fewer revisits to the emergency department.

Patient Complications after Interscalene Block: A Retrospective Comparison of Liposomal Bupivacaine to Nonliposomal Bupivacaine

Background

The purpose of this study was to investigate if the addition of liposome bupivacaine (LB) to an interscalene block (ISB) had an effect on the number of patients with surgical- or block-related complications.

Methods

This was a single-center retrospective chart view performed by identifying patients who received an ISB from January 1, 2014, through April 26, 2018, at the University of Minnesota. 1,518 patients were identified who received an ISB (LB = 784, nonliposomal bupivacaine = 734). Patients were divided into two groups those who did receive liposome bupivacaine in their ISB and those who did not receive liposome bupivacaine in their ISB. Medical records were individually reviewed for surgical procedure, block medications, complications related to the block or surgical procedure, phone calls to the healthcare system for issues related to opioids or pain within 3 and within 30 days, readmissions within 30 days, and emergency room visits for complications within 3 and 30 days.

Results

There was no significant difference in the number of patients with surgical or anesthetic complications. Only phone calls for pain within 3 days were significantly different. The LB group had 3.2% of patients call compared to 5.6% in the nonliposomal bupivacaine group (aOR = 1.71 (95% CI: 1.04–2.87), p=0.036). We found no significant difference in any of the other secondary outcomes.

Conclusions

The use of LB in an ISB demonstrated no significant difference compared to nonliposomal bupivacaine in numbers of complications, emergency room visits, and readmissions.

The use of extended release bupivacaine with transversus abdominis plane and subcostal anterior quadratus lumborum catheters: A retrospective analysis of a novel technique

Background and Aims

Liposomal bupivacaine (LB) is a formulation of local anesthetic that may exert analgesia over a prolonged period. Anecdotal use of LB suggests benefit and prolonged analgesia when used to supplement infiltration blocks. Our aim was to test the effect of a bolus of LB delivered through a nerve catheter in two types of interfascial plane blocks (transversus abdominis plane and anterior subcostal quadratus lumborum). The effect was evaluated through patient self-reporting of postsurgical pain up to 48 postoperative hours.

Material and Methods

Medical records of adult postoperative patients who received LB in a peripheral nerve catheter were followed retrospectively and analysed for pain scores and spread of dermatomal numbness over 48 h following the postoperative dose. A chart review of patients who qualified between June 2015 and March 2017 was performed, and clinical data were obtained from the institutional Perioperative Health Documentation System.

Results

Pain scores decreased following LB bolus, and all patients reported efficient block analgesia after bolus injection. Dermatomal numbness decreased gradually and was minimal by 48 h following bolus.

Conclusion

LB can be injected through a peripheral nerve catheter to prolong analgesia after catheter removal.

[Stocktaking of local anesthetics 2020]

For decades local anesthetics have proven to be safe and effective drugs in the clinical practice, crucially promoting the enormous achievements in regional anesthesia. Meanwhile, it is a well-known fact that local anesthetics are much more than just "simple" sodium channel blockers. They also interact with numerous other ion channels and subcellular structures, enhancing nerve blockade and resulting in systemic "alternative" effects, which can sometimes even be clinically used. By the simultaneous administration of various adjuvants (e.g., opioids, corticosteroids and α₂-receptor agonists) attempts are made to prolong the time of action of local anesthetics after a single administration in order to achieve the best possible improvement in postoperative analgesia. In this context, ultralong-acting local anesthetics, such as liposomal bupivacaine, which at least theoretically can provide a sensory nerve block for several days, have been developed and clinically introduced. The coming years will show whether these approaches will develop into genuine alternatives to the personnel and cost-intensive continuous nerve blockades.Local anesthetic-induced systemic toxicity is meanwhile rare but still a potentially life-threatening event, frequently resulting from accidental intravascular injection or extensive systemic resorption. Consequently, slow and fractional application of these agents with intermittent aspiration helps to prevent toxic sequelae. If toxic symptoms occur, however, the intravenous infusion of 20% lipid solutions in addition to basic treatment measures can enhance the success of treatment.

Preemptive Analgesic Efficacy of the Ultrasound-Guided Bilateral Superficial Serratus Plane Block on Postoperative Pain in Breast Reduction Surgery: A Prospective Randomized Controlled Study

PURPOSE

Breast surgery is an exceedingly common procedure and associated with an increased incidence of acute and chronic pain. Preemptive regional anesthesia techniques may improve postoperative analgesia for patients undergoing breast surgery. The aim of this study was to evaluate the effect of preoperative bilateral serratus plane block on postoperative opioid consumption in patients undergoing breast reduction surgery.

METHODS

After ethical board approval, 40 patients undergoing breast reduction surgery were randomized into 2 groups: control group (Group C, n = 20) and serratus plane block group (Group SPB, n = 20). Group C received bilateral ultrasound-guided 2 ml 0.9% saline subcutaneously each block side, Group SPB received ultrasound-guided bilateral SPB with 0.25% bupivacaine 30 ml each side. The groups were administered the routine general anesthesia protocol. All operations were performed with the mediocentral pedicled reduction mammaplasty technique by the same surgeon. Postoperative analgesia was performed intravenously in the 2 groups twice a day with dexketoprofen trometamol 50 mg and patient-controlled analgesia with fentanyl. Postoperative analgesia was evaluated using the visual analog scale (VAS). Fentanyl consumption, additional analgesia requirement and opioid-related side effects were recorded during the first 24 h after surgery.

RESULTS

Compared with control, the VAS score was statistically lower in the SPB group during all measurement times (p < 0.05). The 24-h opioid consumption was significantly higher in the control group compared with the SPB group (372.50 ± 39.65 vs. 296.25 ± 58.08 μq, respectively; p < 0.001). In addition, the analgesia requirement was statistically lower in the SPB group (8/20 vs. 2/20, respectively, p < 0.028). Nausea or vomiting was observed more often in the control group than in SPB block (9/20 vs. 2/20, respectively, p = 0.013), whereas other side effects were similar for the two groups.

CONCLUSIONS

SPB can be used safely bilaterally in the management of pain for breast reduction surgery as it is easy to perform, provides excellent analgesia, and reduces opioid consumption and opioid sparing effect.

LEVEL OF EVIDENCE II

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

The Role of Exparel Plus Meloxicam for Postoperative Pain Management

PURPOSE OF REVIEW

Acute postoperative pain reduction is a major target against the opioid crisis. While opioids have traditionally been the mainstay for postoperative analgesia, current practice has focused on a multimodal approach to pain control, including ultrasound-guided blocks with longer acting local anesthetic agents.

RECENT FINDINGS

Non-steroidal anti-inflammatory drugs (NSAIDs), such as meloxicam, are an important class of medications utilized to manage pain in the perioperative period. An additional treatment used in perioperative or postoperative pain relief is Exparel, a bupivacaine (sodium channel blocker) liposomal injectable suspension with a 3-4-day duration of action. The long-acting mechanism and formulation of Exparel consistently has demonstrated decreased opioid use and pain scores in patients undergoing many different surgical procedures. A concern is that pH negatively alters the efficacy of bupivacaine, as in cases of inflamed tissue and acidic fluid pH. For this reason, a combination medication with both meloxicam and bupivacaine has been developed, which normalizes pH and has anti-inflammatory and anti-pain conduction properties. Clinical studies demonstrate that this combination agent can be extremely beneficial in treating postoperative pain. This manuscript summarizes the newest developments with regard to liposomal bupivacaine and the non-steroidal meloxicam, their roles in effective treatment of postoperative pain, contraindications, special considerations of using these medications, and future considerations. HTX-011 pairs up a new extended-release formulation of the local anesthetic bupivacaine with meloxicam, a well-established non-steroidal anti-inflammatory drug (NSAID).

Advances in regional anaesthesia and acute pain management: a narrative review

Regional anaesthesia has undergone several exciting advances in the past few decades. Ultrasound-guided techniques of peripheral nerve blockade have become the gold standard thanks to the associated improvements in efficacy, ease of performance and safety. This has increased the accessibility and utilisation of regional anaesthesia in the anaesthesia community at large and is timely given the mounting evidence for its potential benefits on various patient-centred outcomes, including major morbidity, cancer recurrence and persistent postoperative pain. Ultrasound guidance has also paved the way for refinement of the technical performance of existing blocks concerning simplicity and safety, as well as the development of new regional anaesthesia techniques. In particular, the emergence of fascial plane blocks has further broadened the application of regional anaesthesia in the management of painful conditions of the thorax and abdomen. The preliminary results of investigations into these fascial plane blocks are promising but require further research to establish their true value and role in clinical care. One of the challenges that remains is how best to prolong regional anaesthesia to maximise its benefits while avoiding undue harm. There is ongoing research into optimising continuous catheter techniques and their management, intravenous and perineural pharmacological adjuncts, and sustained-release local anaesthetic molecules. Finally, there is a growing appreciation for the critical role that regional anaesthesia can play in an overall multimodal anaesthetic strategy. This is especially pertinent given the current focus on eliminating unnecessary peri-operative opioid administration.

Efficacy of liposomal bupivacaine in shoulder surgery: a systematic review and meta-analysis

HYPOTHESIS

The aim of this meta-analysis was to compare the safety, efficacy, and opioid-sparing effect of liposomal bupivacaine (LB) vs. nonliposomal local anesthetic agents (NLAs) for postoperative analgesia after shoulder surgery.

METHODS

A systematic literature review of randomized controlled clinical studies comparing the efficacy of LB with NLAs in shoulder surgery was conducted. Seven level I and II studies were included in the meta-analysis, and shoulder surgical procedures included arthroscopic rotator cuff repair and shoulder arthroplasty. Bias was assessed using The Cochrane Collaboration's tool. The primary outcome measures were visual analog scale pain scores and opioid consumption 24 and 48 hours after shoulder surgery. Subgroup analysis was performed for the method of LB administration (interscalene nerve block vs. local infiltration).

RESULTS

A total of 7 studies (535 patients) were included in the final meta-analysis comparing LB (n = 260) with NLAs (n = 275). No significant difference was found between the LB and NLA groups in terms of visual analog scale pain scores at 24 hours (95% confidence interval, -1.02 to 0.84; P = .86) and 48 hours (95% confidence interval, -0.53 to 0.71; P = .78). Both groups had comparable opioid consumption at both 24 hours (P = .43) and 48 hours (P = .78) postoperatively and with respect to length of stay (P = .87) and adverse events (P = .97). Subgroup analysis demonstrated comparable efficacy irrespective of the method of administration of LB.

CONCLUSION

LB is comparable to NLAs with respect to pain relief, the opioid-sparing effect, and adverse effects in the first 48 hours after arthroscopic rotator cuff repair and total shoulder arthroplasty.

Peripheral nerve catheters: A critical review of the efficacy

Continuous peripheral nerve blocks are commonly used for postoperative analgesia after surgery. However, catheter failure may occur due to either primary (incorrect insertion) or secondary reasons (displacement, obstruction, disconnection). Catheter failure results in unanticipated pain, need for opioid use, and risk of readmission or delay in hospital discharge. This review aimed to assess definition and frequency of catheter failure, and discuss the alternatives to prolong duration of single-shot nerve blocks. A literature search was performed on peripheral catheters reporting failure as the main outcome measure. Thirty-three studies met the selection criteria, comprising 2711 catheters. Literature review suggests that peripheral nerve catheters have clinically significant failure rate when the assessment is performed using an objective (imaging) method. Subjective methods of assessment (without imaging) may underestimate the incidence of catheter failure.

Peripheral nerve blocks for postoperative analgesia: From traditional unencapsulated local anesthetic to liposomes, cryoneurolysis and peripheral nerve stimulation

Peripheral nerve blocks (PNBs) using local anesthetics either via single injection or continuous perineural catheter have been the mainstay for regional anesthesia and are a vital component of postoperative multimodal opioid-sparing pain management. There are some limitations to PNBs, however, mainly its limited duration of action, but also risk of catheter-associated infection and dislodgements. Furthermore, local anesthetic-based blocks can induce sensory deficits and motor weakness, possibly increasing the risk of falling and/or decreasing the ability to participate in postoperative rehabilitation. In this review, we first discuss various local anesthetic-based PNB techniques for major surgery and then review newer modalities, including liposome bupivacaine, cryoanalgesia, and peripheral nerve stimulation; all of which may offer advantages over single and continuous local anesthetic-based PNBs.

Improved pain control with adductor canal block using liposomal bupivacaine after total knee replacement: a retrospective cohort study

Background

Adductor canal blocks (ACBs), typically administered with a local anesthetic such as bupivacaine, help control perioperative pain after total knee arthroplasty. Recently, liposomal bupivacaine (LB) was introduced in an attempt to extend the duration of analgesia, used primarily in periarticular injections (PAIs). The purpose of this study was to compare pain control and early perioperative outcomes with ACB using LB vs standard bupivacaine (SB).

Methods

We retrospectively compared pain control in a group of 75 patients with ACB and PAI with SB to that of a cohort of 75 patients who received ACB and PAI with LB. The primary outcome measure was pain measured using the visual analog score. The secondary outcome measures were morphine equivalents of pain medication (ME), physical therapy distance ambulated, disposition status, and length of stay.

Results

There were no significant differences between the two cohorts for age, gender, body mass index, preoperative diagnosis, or American Society of Anesthesiologists. Visual analog scores were significantly lower in the LB group for postoperative day (POD) 0 (2.1 vs 2.8, P = .046), POD 1 (2.2 vs 3.3, P < .001), and POD 2 (2.1 vs 3.7, P = .001) than those in the SB group. The LB group consumed significantly fewer ME on the POD 0 (18.7 vs 25.2, P = .02) and POD 1 (23.4 vs 37.8, P = .003), as well as overall ME/day (24.6 vs 41.7, P < .001). The LB group walked more on POD 0 (261.6 vs 108.2, P < .001) and POD 1 (761.5 vs 372.0, P < .001).

Conclusions

We report improved outcomes across all measures for the LB group. There were no adverse events. This study supports the use of LB for ACBs in total knee arthroplasty.

Percutaneous peripheral nerve stimulation for acute postoperative pain

Peripheral nerve stimulation or peripheral neuromodulation is a modality utilized for decades to manage chronic pain. There have been recent studies published describing its use in managing acute surgical pain for orthopedic surgery. The postoperative acute pain associated with several types of surgeries often outlasts the analgesia duration provided by single and continuous peripheral nerve blocks. Ultrasound-guided percutaneous peripheral nerve stimulation has the potential to provide much longer analgesia for acute pain while avoiding some limitations associated with local anesthetic-based peripheral nerve blocks. We summarize the current devices used in published studies to demonstrate feasibility with a focus on acute pain control.

Outcomes of Ambulatory Upper Extremity Surgery Patients Discharged Home with Perineural Catheters from a Veterans Health Administration Medical Center

Objective

The feasibility and safety of managing ambulatory continuous peripheral nerve blocks (CPNB) in Veterans Health Administration (VHA) patients are currently unknown. We aimed to characterize the outcomes of a large VHA cohort of ambulatory upper extremity surgery patients discharged with CPNB and identify differences, if any, between catheter types.

Methods

With institutional review board approval, we reviewed data for consecutive patients from a single VHA hospital who had received ambulatory CPNB for upper extremity surgery from March 2011 to May 2017. The composite primary outcome was the occurrence of any catheter-related issue or additional all-cause health care intervention after discharge. Our secondary outcome was the ability to achieve regular daily telephone contact.

Results

Five hundred one patients formed the final sample. The incidence of any issue or health care intervention was 104/274 (38%) for infraclavicular, 58/185 (31%) for interscalene, and 14/42 (33%) for supraclavicular; these rates did not differ between groups. Higher ASA status was associated with greater odds of having any issue, whereas increasing age was slightly protective. Distance was associated with an increase in catheter-related issues (P < 0.01) but not additional health care interventions (P = 0.51). Only interscalene catheter patients (3%) reported breathing difficulty. Infraclavicular catheter patients had the most emergency room visits but rarely for CPNB issues. Consistent daily telephone contact was not achieved.

Conclusions

For VHA ambulatory CPNB patients, the combined incidence of a catheter-related issue or additional health care intervention was approximately one in three patients and did not differ by brachial plexus catheter type. Serious adverse events were generally uncommon.

What Pain Levels Do TSA Patients Experience When Given a Long-acting Nerve Block and Multimodal Analgesia?

BACKGROUND

The pain experience for total shoulder arthroplasty (TSA) patients in the first 2 weeks after surgery has not been well described. Many approaches to pain management have been used, with none emerging as clearly superior; it is important that any approach minimizes postoperative opioid use.

QUESTIONS/PURPOSES

(1) With a long-acting nerve block and comprehensive multimodal analgesia, what are the pain levels after TSA from day of surgery until postoperative day (POD) 14? (2) How many opioids do TSA patients take from the day of surgery until POD 14? (3) What are the PainOUT responses at POD 1 and POD 14, focusing on side effects from opioids usage?

METHODS

From January 27, 2017 to December 6, 2017, 154 TSA patients were identified as potentially eligible for this prospective, institutional review board-approved observational study. Of those, 46 patients (30%) were excluded (either because they were deemed not appropriate for the study, research staff were not available, patients were not eligible, or they declined to participate), and another six (4%) had incomplete followup data and could not be studied, leaving 102 patients (66%) for analysis here. Median preoperative pain with movement was 7 (interquartile range [IQR], 5-9) and 13 of 102 patients used preoperative opioids. All patients received a single-injection bupivacaine interscalene block with adjuvant clonidine, dexamethasone, and buprenorphine. Multimodal analgesia included acetaminophen, NSAIDs, and opioids. The primary outcome was the Numerical Rating Scale (NRS) pain score with movement on POD 14. The NRS pain score ranges from 0 (no pain) to 10 (worst pain possible). Secondary outcomes included NRS pain scores at rest and with movement (day of surgery, and PODs 1, 3, 7 and 14), daily analgesic use from day of surgery to POD 14 (both oral and intravenous), Opioid-Related Symptom Distress Scale (which assesses 12 symptoms ranging from 0 to 4, with 4 being the most distressing; the composite score is the mean of the 12 symptom-specific scores) on POD 1, and the PainOut questionnaire on POD 1 and POD 14. The PainOut questionnaire includes questions rating nausea, drowsiness, itching from 0 (none) to 10 (severe), as well as rating difficulty staying asleep from 0 (does not interfere) to 10 (completely interferes).

RESULTS

The median NRS pain scores with movement were 2 (IQR, 0-5) on POD 1, 5 (IQR, 3-6) on POD 3, and the pain score was 3 (IQR, 1-5) on POD 14. Median total opioid use (converted to oral morphine equivalents) was 16 mg (4-50 mg) for the first 24 hours, 30 mg (8-63 mg) for the third, and 0 mg (0-20 mg) by the eighth 24-hour period, while the most frequent number of activations of the intravenous patient-controlled analgesia device was 0. Median PainOut scores on POD 1 and POD 14 for sleep interference, nausea, drowsiness and itching were 0, and the median composite Opioid-Related Symptom Distress Scale score on day 1 was 0.3 (IQR, 0.1-0.5).

CONCLUSIONS

Clinicians using this protocol, which combines a long-acting, single-injection nerve block with multimodal analgesia, can inform TSA patients that their postoperative pain will likely be less than their preoperative pain, and that on average they will stop using opioids after 7 days. Future research could investigate what the individual components of this protocol contribute. Larger cohort studies or registries would document the incidence of rare complications. Randomized controlled trials could directly compare analgesic effectiveness and cost-benefits for this protocol versus alternative strategies, such as perineural catheters or liposomal bupivacaine. Perhaps most importantly, future studies could seek ways to further reduce peak pain and opioid usage on POD 2 and POD 3.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Liposomal Bupivacaine Does Not Reduce Inpatient Opioid Prescription or Related Complications after Knee Arthroplasty: A Database Analysis

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

WHAT THIS MANUSCRIPT TELLS US THAT IS NEW: BACKGROUND:: Although some trials suggest benefits of liposomal bupivacaine, data on real-world use and effectiveness is lacking. This study analyzed the impact of liposomal bupivacaine use (regardless of administration route) on inpatient opioid prescription, resource utilization, and opioid-related complications among patients undergoing total knee arthroplasties with a peripheral nerve block. It was hypothesized that liposomal bupivacaine has limited clinical influence on the studied outcomes.

METHODS

The study included data on 88,830 total knee arthroplasties performed with a peripheral nerve block (Premier Healthcare Database 2013 to 2016). Multilevel multivariable regressions measured associations between use of liposomal bupivacaine and (1) inpatient opioid prescription (extracted from billing) and (2) length of stay, cost of hospitalization, as well as opioid-related complications. To reflect the difference between statistical and clinical significance, a relative change of -15% in outcomes was assumed to be clinically important.

RESULTS

Overall, liposomal bupivacaine was used in 21.2% (n = 18,817) of patients that underwent a total knee arthroplasty with a peripheral nerve block. Liposomal bupivacaine use was not associated with a clinically meaningful reduction in inpatient opioid prescription (group median, 253 mg of oral morphine equivalents, adjusted effect -9.3% CI -11.1%, -7.5%; P < 0.0001) and length of stay (group median, 3 days, adjusted effect -8.8% CI -10.1%, -7.5%; P < 0.0001) with no effect on cost of hospitalization. Most importantly, liposomal bupivacaine use was not associated with decreased odds for opioid-related complications.

CONCLUSIONS

Liposomal bupivacaine was not associated with a clinically relevant improvement in inpatient opioid prescription, resource utilization, or opioid-related complications in patients who received modern pain management including a peripheral nerve block.

An evaluation of the analgesic effect of AnestaGel™ on mechanical allodynia in a rat model of postoperative incisional pain

Purpose

Sustained release hydrogel with bupivacaine (AnestaGel^™) is a novel formulation of extended release bupivacaine in a biohydrogel Matrix^™. We sought to compare the analgesic effects via mechanical allodynia, the pharmacokinetic characteristics via serum blood levels, and the local tissue effects via pathology, following injection of either sustained release hydrogel with bupivacaine, liposome bupivacaine, or hydrogel only (negative control group).

Materials and methods

Ninety rats (30 in each group) were randomized to receive a sciatic nerve block injection of either sustained release hydrogel with bupivacaine, liposome bupivacaine (Exparel^®), or a biohydrogel matrix. The total force generated was obtained at varying time points. Pathologic analysis was undertaken on days 5 and 42 of the study. Six additional rats (two in each group) were randomized to receive a sciatic nerve block injection of either sustained release hydrogel with bupivacaine, liposome bupivacaine, or bupivacaine and pharmacokinetic data were obtained for up to 120 hours.

Results

The sustained release hydrogel with bupivacaine group had significantly better response to mechanical allodynia compared to the other two groups. The pathology showed no significant adverse events at 42 days in any group. Finally, bupivacaine was present longer in the serum of sustained release hydrogel with bupivacaine group than the other two groups.

Conclusion

The sustained release hydrogel with bupivacaine achieved longer lasting analgesia with no significant findings on pathology at 42 days when compared to both positive and negative controls.