Analgesic Effectiveness of Liposomal Bupivacaine versus Plain Local Anesthetics for Abdominal Fascial Plane Blocks: A Systematic Review and Meta-analysis of Randomized Trials

BACKGROUND

Liposomal bupivacaine is reported to prolong the duration of analgesia when used for abdominal fascial plane blocks compared to plain local anesthetics; however, evidence from randomized trials is mixed. This meta-analysis aims to compare the analgesic effectiveness of liposomal bupivacaine to plain local anesthetics in adults receiving abdominal fascial plane blocks.

METHODS

Randomized trials comparing liposomal bupivacaine and plain (nonliposomal) local anesthetics in abdominal fascial plane blocks were sought. The primary outcome was area under the curve rest pain between 24 to 72 h postoperatively. Secondary outcomes included rest pain at individual timepoints (1, 6, 12, 24, 48, and 72 h); analgesic consumption at 0 to 24, 25 to 48, and 49 to 72 h; time to analgesic request; hospital stay duration; and opioid-related side effects. Data were pooled using the Hartung-Knapp-Sidik-Jonkman random effects method.

RESULTS

Sixteen trials encompassing 1,287 patients (liposomal bupivacaine, 667; plain local anesthetics, 620) were included. The liposomal bupivacaine group received liposomal bupivacaine mixed with plain bupivacaine in 10 studies, liposomal bupivacaine alone in 5 studies, and both preparations in 1 three-armed study. No difference was observed between the two groups for area under the curve pain scores, with a standardized mean difference (95% CI) of -0.21 cm.h (-0.43 to 0.01; P = 0.058; I2 = 48%). Results were robust to subgroup analysis based on (1) potential conflict of interest and (2) mixing of plain local anesthetics with liposomal bupivacaine. The two groups were not different for any of the day 2 or day 3 secondary outcomes.

CONCLUSIONS

This systematic review and meta-analysis suggests similar analgesic effectiveness between liposomal bupivacaine and plain local anesthetics when used for fascial plane block of the abdominal wall. The authors' analysis does not support an evidence-based preference for liposomal bupivacaine compared to plain local anesthetics for abdominal fascial plane blocks.

EDITOR’S PERSPECTIVE

Network meta-analysis of the analgesic effectiveness of regional anaesthesia techniques for anterior cruciate ligament reconstruction

Anterior cruciate ligament reconstruction can cause moderate to severe acute postoperative pain. Despite advances in our understanding of knee innervation, consensus regarding the most effective regional anaesthesia techniques for this surgical population is lacking. This network meta-analysis compared effectiveness of regional anaesthesia techniques used to provide analgesia for anterior cruciate ligament reconstruction. Randomised trials examining regional anaesthesia techniques for analgesia following anterior cruciate ligament reconstruction were sought. The primary outcome was opioid consumption during the first 24 h postoperatively. Secondary outcomes were: rest pain at 0, 6, 12 and 24 h; area under the curve of pain over 24 h; and opioid-related adverse effects and functional recovery. Network meta-analysis was conducted using a frequentist approach. A total of 57 trials (4069 patients) investigating femoral nerve block, sciatic nerve block, adductor canal block, local anaesthetic infiltration, graft-donor site infiltration and systemic analgesia alone (control) were included. For opioid consumption, all regional anaesthesia techniques were superior to systemic analgesia alone, but differences between regional techniques were not significant. Single-injection femoral nerve block combined with sciatic nerve block had the highest p value probability for reducing postoperative opioid consumption and area under the curve for pain severity over 24 h (78% and 90%, respectively). Continuous femoral nerve block had the highest probability (87%) of reducing opioid-related adverse effects, while local infiltration analgesia had the highest probability (88%) of optimising functional recovery. In contrast, systemic analgesia, local infiltration analgesia and adductor canal block were each poor performers across all analgesic outcomes. Regional anaesthesia techniques that target both the femoral and sciatic nerve distributions, namely a combination of single-injection nerve blocks, provide the most consistent analgesic benefits for anterior cruciate ligament reconstruction compared with all other techniques but will most likely impair postoperative function. Importantly, adductor canal block, local infiltration analgesia and systemic analgesia alone each perform poorly for acute pain management following anterior cruciate ligament reconstruction.

Analgesic benefits of the quadratus lumborum block in total hip arthroplasty: a systematic review and meta-analysis

The quadratus lumborum block (QLB) is reported to reduce pain and improve function following total hip arthroplasty; however, randomised controlled trials evaluating the benefits of adding this block to general or spinal anaesthesia in this population are conflicting. We performed a systematic review seeking randomised controlled trials investigating QLB benefits for total hip arthroplasty, stratifying comparisons regarding the addition of QLB to either general or spinal anaesthesia. The primary outcome was 24-h area under the curve (AUC) pain score. Pain scores were interpreted in the context of a population-specific minimal clinically important difference of 1.86 cm on a 10-cm visual analogue scale, or an AUC pain score of 5.58 cm.h. Secondary outcomes included analgesic consumption, functional recovery and opioid-related side-effects. In all, 18 trials (1318 patients) were included. Adding QLB to general or spinal anaesthesia improved 24-h AUC rest pain scores by a mean difference (95%CI) of -3.56 cm.h (-6.70 to -0.42; p = 0.034) and - 4.19 cm.h (-7.20 to -1.18; p = 0.014), respectively. These improvements failed to reach the pre-determined minimal clinically important difference, as did the reduction in analgesic consumption. Quadratus lumborum block improved functional recovery for general, but not spinal, anaesthesia. Opioid-related side-effects were reduced with QLB regardless of anaesthetic modality. Low-to-moderate quality evidence suggests that the extent to which adding QLB to either general or spinal anaesthesia reduces postoperative pain and opioid consumption after total hip arthroplasty is statistically significant but may be clinically unimportant for most patients. However, adding QLB to general anaesthesia might enhance functional recovery. Taken together, our findings do not support the routine use of QLB as part of multimodal analgesic regimens for total hip arthroplasty.

Evaluating the incidence of spinal cord injury after spinal cord stimulator implant: an updated retrospective review

INTRODUCTION

While spinal cord stimulator implant is an increasingly safe procedure, one of the most feared complications is spinal cord injury. Still, literature regarding its incidence remains highly variable. This retrospective analysis aims to evaluate the incidence of spinal cord injury after spinal cord stimulator implant using a large-scale claims database.

METHODS

The PearlDiver-Mariner database of national all payer claims was used to identify patients who underwent spinal cord stimulator implant (percutaneous or paddle) and developed subsequent spinal cord injury within 45 days. The primary outcome was to determine the overall incidence of spinal cord injury after spinal cord stimulator implant. Secondary outcomes included an evaluation of potential factors associated with developing spinal cord injury using univariable and multivariable regression analysis.

RESULTS

A total of 71,172 patients who underwent a spinal cord stimulator implant were included in the analysis, of which 52,070 underwent percutaneous and 19,102 underwent paddle spinal cord stimulator lead implant. The overall incidence of spinal cord injury after spinal cord stimulator implant (any lead type) was found to be 0.42% (302 patients). The incidence of spinal cord injury after percutaneous and paddle lead implants did not differ at 0.45% (233 patients) and 0.36% (69 patients)(p=0.12), respectively. Overall, variables associated with a significantly increased OR (95% confidence interval) of developing spinal cord injury included male gender by 1.31 times (1.04 to 1.65)(p=0.02); having a claim for low molecular weight heparin within 30 days by 3.99 times (1.47 to 10.82)(p<0.01); a diagnosis for osteoporosis within 1 year by 1.75 times (1.15 to 2.66)(p<0.01); and a diagnosis of cervical or thoracic spinal canal stenosis within 1 year by 1.99 (1.37 to 2.90)(p<0.001) and 4.00 (2.63 to 6.09)(p<0.0001) times, respectively.

CONCLUSIONS

Overall, our results support the notion that spinal cord stimulator implant continues to be a safe procedure for chronic pain patients. However, risk factor mitigation strategies for the prevention of spinal cord injury after spinal cord stimulator implant should be undertaken prior to performing the procedure.

Integrin-mediated interactions with a laminin-presenting substrate modulate biosynthesis and phenotypic expression for cells of the human nucleus pulposus

With aging and pathology, cells of the nucleus pulposus (NP) de-differentiate towards a fibroblast-like phenotype, a change that contributes to degeneration of the intervertebral disc (IVD). Laminin isoforms are a component of the NP extracellular matrix during development but largely disappear in the adult NP tissue. Exposing human adult NP cells to hydrogels made from PEGylated-laminin-111 (PEGLM) has been shown to regulate NP cell behaviors and promote cells to assume a biosynthetically active state with gene/protein expression and morphology consistent with those observed in juvenile NP cells. However, the mechanism regulating this effect has remained unknown. In the present study, the integrin subunits that promote adult degenerative NP cell interactions with laminin-111 are identified by performing integrin blocking studies along with assays of intracellular signaling and cell phenotype. The findings indicate that integrin α3 is a primary regulator of cell attachment to laminin and is associated with phosphorylation of signaling molecules downstream of integrin engagement (ERK 1/2 and GSK3β). Sustained effects of blocking integrin α3 were also demonstrated including decreased expression of phenotypic markers, reduced biosynthesis, and altered cytoskeletal organization. Furthermore, blocking both integrin α3 and additional integrin subunits elicited changes in cell clustering, but did not alter the phenotype of single cells. These findings reveal that integrin- mediated interactions through integrin α3 are critical in the process by which NP cells sense and alter phenotype in response to culture upon laminin and further suggest that targeting integrin α3 has potential for reversing or slowing degenerative changes to the NP cell.

MON-674 Diabetic Amyotrophy; A Rare Cause of Muscle Weakness

Background: Diabetic amyotrophy is a rare complication of type 2 diabetes mellitus. There is little existing evidence contributing to projected outcomes for patients recovering from diabetic amyotrophy.Clinical Case: A 42 year-old man presented with lower extremity muscle pain and progressive proximal muscle weakness over 8 months. He developed asymmetrical muscle weakness in the lower extremities with diffuse pain and sensitivity to touch. He also had 80 pounds weight loss, diarrhea, and erectile dysfunction over the same time period. He had a past medical history of asthma, chronic migraines, and type II diabetes mellitus with A1c 7.1. His medications included high dose prednisone to treat his chronic migraines and asthma. Exam revealed generalized muscle atrophy, asymmetric proximal weakness, areflexia, with sensory loss in bilateral lower limbs.ESR, CRP, ANA, anti-HMG CoA reductase, CK, aldolase, SPEP, and myomarker panel were all within normal limits. Treponema pallidum and Bartonella serologies were negative. CSF evaluation was not suggestive of any demyelinating or neuromuscular disease. Full body STIR MRI demonstrated muscle edema in abductor, gluteus minimus, and paraspinal muscles bilaterally. EMG testing revealed acute to subacute active asymmetrical polyradiculoneuropathy and evidence of chronic proximal myopathy.Based on clinical presentation, EMG findings, and lack of evidence to support alternative diagnoses, he was diagnosed with diabetic amyotrophy and was started on IVIG and methylprednisolone with improvement in pain but very minimal improvement in weakness. Unfortunately, the expected clinical course following a diagnosis of diabetic amyotrophy is one of minimal improvement with treatment, as was the case in our patient.Conclusion: Diabetic amyotrophy is a rare complication of type 2 diabetes mellitus which typically presents with muscle weakness followed by severe pain in the thighs, hips, and buttocks. Compared with other neurologic complications of diabetes, amyotrophy is relatively uncommon, affecting approximately 1 percent of patients. This low prevalence and the broad differential for proximal muscle weakness makes it challenging to diagnose. It remains a diagnosis of exclusion, though EMG studies showing polyradiculoneuropathy in the proximal leg musculature is suggestive. Clinical improvement is slow and often incomplete. Physical and occupational therapy are a mainstay of treatment which may also include IVIG and steroids aimed at treating associated pain. Endocrinologists should have a high clinical suspicion for diabetic amyotrophy in the appropriate clinical context. When considering the diagnosis and discussing treatment options with patients, this case highlights the important role of endocrinologists discussing expectations associated with projected outcomes while attempting to manage diabetic amyotrophy.

Towards universal ambient ionization: direct elemental analysis of solid substrates using microwave plasma ionization

A microwave plasma was used for direct ambient ionization mass spectrometry of solid substrates, rapidly yielding atomic spectra without sample digestion or pre-treatment. Further, molecular spectra for the organic components of the substrate were obtained simultaneously, in an ambient ionization format. Initial characterization of the microwave plasma coupling to an ion trap mass spectrometer was carried out using solution standards and a microwave plasma torch (MPT) configuration. The configuration of the microwave plasma was then optimized for ambient ionization. The atomic and organic composition for samples applicable to nuclear and conventional forensic screening, including explosive/radionuclide mixtures and inorganic/organic gunshot residue component mixtures were successfully determined. The technologies employed are readily fieldable; the feasibility of a multimode ion source that could be coupled with a portable ion trap mass spectrometer for rapid, on-site, elemental, isotopic, and molecular screening of samples is demonstrated.

Evidence for a Soft Nuclear Equation-of-State from Kaon Production in Heavy-Ion Collisions

The production of pions and kaons has been measured in 197Au+197Au collisions at beam energies from 0.6 to 1.5A GeV with the kaon spectrometer at SIS/GSI. The K+ meson multiplicity per nucleon is enhanced in Au+Au collisions by factors up to 6 relative to C+C reactions, whereas the corresponding pion ratio is reduced. The ratio of the K+ meson excitation functions for Au+Au and C+C collisions increases with decreasing beam energy. This behavior is expected for a soft nuclear equation-of-state.

Emission pattern of high-energy pions: A new probe for the early phase of heavy-Ion collisions

The emission pattern of charged pions has been measured in Au+Au collisions at 1 GeV/nucleon incident energy. In peripheral collisions and at target rapidities, high-energy pions are emitted preferentially towards the target spectator matter. In contrast, low-energy pions are emitted predominantly in the opposite direction. The corresponding azimuthal anisotropy is explained by the interaction of pions with projectile and target spectator matter. This interaction with the spectator matter causes an effective shadowing which varies with time during the reaction. Our observations show that high-energy pions stem from the early stage of the collision whereas low-energy pions freeze out later.

[Cochlear implants]

Cochlear implantation is a method of utmost importance recently employed in ear surgery. It makes even speech understanding possible with electrical stimulation of the inner ear in case of bilateral total deafness of cochlear origin. The authors have performed cochlear implantation for 10 years at the Ear-Nose and Throat Clinic of Semmelweis University. Since 1985 different implantation techniques have been used in case of 58 patients, both adults and children. The authors give account of of technical details, rapidly changing selection criteria and the call attention to the problems of peri- and postoperative period and rehabilitation, on they basis of their own results. Importance of team-work of the ear-surgeon, audiologist, psychologist, physicist and speech-therapist is emphasized, because success of the operation is based on proper selection, skillful operating techniques and postoperative rehabilitation, as well.

Etoposide combined with cyclophosphamide plus vincristine compared with doxorubicin plus cyclophosphamide plus vincristine and with high-dose cyclophosphamide plus vincristine in the treatment of small-cell carcinoma of the lung: a randomized trial of the Bristol Lung Cancer Study Group

A total of 353 patients with previously untreated small-cell lung cancer (SCLC) were accrued in this multicenter trial. Patients were randomly assigned to receive one of the following three regimens: cyclophosphamide 1,000 mg/m2 intravenously (IV) day 1, vincristine 1.4 mg/m2 IV day 1, and etoposide 50 mg/m2 IV day 1, followed by etoposide 100 mg/m2/day orally days 2 through 5 (CEV); cyclophosphamide 1,000 mg/m2 IV day 1, vincristine 1.4 mg/m2 IV day 1, and doxorubicin 50 mg/m2 IV day 1 (CAV); cyclophosphamide 2,000 mg/m2 day 1 and vincristine 1.4 mg/m2 IV day 1 (CV). Cycles were repeated every 3 weeks. Treatment groups were comparable with respect to extent of disease, age, sex, performance status, and metastatic sites. No significant differences in response rates, response duration, or survival could be detected in limited disease, although there appeared to be a trend favoring CEV. Among extensive-disease patients, response duration on the CEV regimen was longer than on the CV regimen or the CAV program (P less than .001). The superiority of the CEV regimen was also demonstrated in the survival analysis in which differences attained statistical significance (P = .01). In this group the median survival was increased from 29 weeks on CV to 31 weeks on CAV and 39 weeks on CEV. Myelosuppression was the most frequent toxicity. It was more severe with CV than CEV or CAV. Most nonhematologic side effects were comparable among the three treatment groups. However, the high doses of cyclophosphamide in the CV regimen produced a higher incidence of hemorrhagic cystitis than in the CEV or CAV programs (P less than .001). Cardiotoxicity only occurred in the CAV group (P = .05). The addition of etoposide to the CV regimen resulted in significantly longer response duration and survival without increased toxicity. Similarly, the substitution of etoposide for the doxorubicin in the CAV regimen was associated with prolonged survival and reduced cardiotoxicity.

Prenatal diagnosis of Duchenne muscular dystrophy: prospective linkage analysis and retrospective dystrophin cDNA analysis

The accuracy of DNA-based prenatal diagnosis of Duchenne muscular dystrophy (DMD) was determined by study of 174 families. Only 60% of families had a living affected male, and 63% had history of a single affected male. Prenatal diagnosis was declined by 47% of mothers whose DNA studies predicted a carrier risk below 2%, and none have had affected sons. Fetal risk was estimated prospectively by linkage analysis using intragenic and flanking RFLPs and retrospectively using dystrophin cDNA analysis for families whose linkage estimates lacked precision. Diagnostic accuracy was determined by comparing predictions with 40 male pregnancy outcomes. On the basis of linkage analysis, we anticipated 3.2 DMD males and observed 3.0. Retrospective cDNA analysis identified deletions in 2 of these 3 males. The combined use of linkage and cDNA deletion analysis provided a highly accurate method for prenatal diagnosis of DMD.

Analysis of deletions in DNA from patients with Becker and Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked recessive genetic disorder for which the biochemical defect is as yet unknown. Recently, two cloned segments of human X-chromosome DNA have been described which detect structural alterations within or near the genetic locus responsible for the disorder. Both of these cloned segments were described as tightly linked to the locus and were capable of detecting deletions in the DNA of boys affected with DMD. In an attempt to determine more precisely the occurrence of these deletions within a large population of DMD patients and the accuracy of one of the segments, DXS164 (pERT87), in determining the inheritance of the DMD X chromosome, the subclones 1, 8 and 15 were made available to many investigators throughout the world. Here we describe the combined results of more than 20 research laboratories with respect to the occurrence of deletions at the DXS164 locus in DNA samples isolated from patients with DMD and Becker muscular dystrophy (BMD). The results indicate that the DXS164 locus apparently recombines with DMD 5% of the time, but is probably located between independent sites of mutation which yield DMD. The breakpoints of some deletions are delineated within the DXS164 locus, and it is evident that the deletions at the DMD locus are frequent and extremely large.

Prognostic factors for survival of 194 patients with low infiltrate leukemia

Prognostic factors were identified from the histories of 194 patients diagnosed as having low infiltrate leukemia (LIL) between 1973 and 1981, when the policy was to delay treatment until there was evidence of progressive disease or life-threatening morbidity. Their median age was 59 yr; 63% were male; 30 had had a malignant disease previously. Presenting symptoms included anemia, 82%; infections, 15%; and hemorrhage, 16%. The group's median survival was 42 weeks, with high marrow cellularity and percentage of blasts, impairment of bone marrow, liver or renal function, age over 65 yr and performance status less than 80% associated with poorer survival. Cytogenetic changes associated with poor survival included loss of chromosome 5 or 7, additional chromosome 8, karyotypic instability, and presence of 100% abnormal metaphases. A regression model including terms for blood and bone marrow features, and age at hospital admission was able to stratify patients into prognostic groups in the same population and in an independent population admitted prior to 1973. Further prospective testing of the model is required. Twenty-six of the 78 patients who were eventually treated with combination chemotherapy achieved complete remission. The presence of Auer rods, diagnosis of acute leukemia or refractory anemia with excess blasts, rapid increase in marrow infiltrate and favorable cytogenetic karyotype were associated with response. Delaying treatment in all patients was found to have improved only modestly the survival of patients with LIL.

Combination chemotherapy with BCNU, vincristine, mitomycin-C and prednisone in refractory breast carcinoma. A pilot study

21 patients with metastatic breast cancer, refractory to conventional agents, were treated with a combination of BCNU, vincristine, mitomycin-C and prednisone given every 4 weeks. Only three of the nineteen (15.8%) evaluable patients were observed to have a partial remission, whereas four experienced stabilization of tumor. The sites which responded included skin lesions in two patients and a pleural effusion in 1 patient. This combination resulted in moderate to severe thrombocytopenia in five patients, but was otherwise well tolerated. This pilot study therefore suggests that these four agents in the schedule and doses given do not appear to be superior to any of these agents used singly for advanced, refractory breast cancer.

Vindesine in advanced breast cancer, lymphoma and melanoma. A Colorado Clinical Oncology Group study

Fifty-six patients with advanced metastatic carcinoma of the breast, melanoma and lymphoma were treated with the new vinca alkaloid vindesine in a prospective Phase II study. The dose was 3 mg/M2 by I.V. bolus once a week for a minimum of two doses. Patients who failed to respond to four I.V. doses were treated with 48-h intravenous infusions at a dose of 1.5 mg/M2 per 24 h. Of the 26 evaluable patients with breast cancer, there were only two incomplete responses and four patients who experienced stabilization of disease. Of the 12 evaluable patients with melanoma, no responses were seen with four patients experiencing stabilization of disease. Of the 11 patients with non-Hodgkin's lymphomas, there was one complete remission which persisted for 26 months and two partial remissions. No additional responses were seen when the mode of administration was changed to 48-h infusion in three patients with breast cancer, five patients with melanoma and one patient with lymphoma. Significant toxicities included neutropenia in 24 patients and nausea and vomiting in two patients. There were no drug related deaths. Previously reported experience with vindesine in these tumors is reviewed as well.

tRNA breakdown products as markers for cancer

Seven breakdown products of tRNA were quantitated by high pressure liquid chromatography in urine and were related to the creatinine content. In the urine of 26 of 27 patients with 13 different malignancies, there was an elevation of one or more of these "markers." The levels of excretion vary approximately with the stage of the disease.