Role of VVZ-149, a Novel Analgesic Molecule, in the Affective Component of Pain: Results from an Exploratory Proof-of-Concept Study of Postoperative Pain following Laparoscopic and Robotic-Laparoscopic Gastrectomy.

OBJECTIVE: VVZ-149 is a small molecule that both inhibits the glycine transporter type 2 and the serotonin receptor 5 hydroxytryptamine 2 A. In a randomized, parallel-group, and double-blind trial (NCT02844725), we investigated the analgesic efficacy and safety of VVZ-149 Injections, which is under clinical development as a single-use injectable product for treating moderate to severe postoperative pain. METHODS: Sixty patients undergoing laparoscopic and robotic-laparoscopic gastrectomy were randomly assigned to receive a 10-hour intravenous infusion of VVZ-149 Injections or placebo, initiated approximately 1 hour before completion of surgical suturing. Major outcomes included pain intensity and opioid consumption via patient-controlled analgesia and rescue analgesia provided "as needed." The treatment efficacy of VVZ-149 was further examined in a subpopulation requiring early rescue medication, previously associated with the presence of high levels of preoperative negative affect in a prior Phase 2 study (NCT02489526). RESULTS: Pain intensity was lower in the VVZ-149 (n = 30) than the placebo group (n = 29), reaching statistical significance at 4 hours post-emergence (P < .05), with a 29.5% reduction in opioid consumption for 24 hours and fewer demands for patient-controlled analgesia. In the rescued subgroup, VVZ-149 further reduced pain intensity (P < .05) with 32.6% less opioid consumption for 24 hours compared to placebo patients. CONCLUSIONS: VVZ-149 demonstrated effective analgesia with reduced postoperative pain and opioid requirements. Consistent with the results from the previous Phase 2 study, patients with early rescue requirement had greater benefit from VVZ-149, supporting the hypothesis that VVZ-149 may alleviate the affective component of pain and mitigate excessive use of opioids postoperatively.

Brachial Plexus Block with Liposomal Bupivacaine for Shoulder Surgery Improves Analgesia and Reduces Opioid Consumption: Results from a Multicenter, Randomized, Double-Blind, Controlled Trial.

OBJECTIVE: The utility of single-injection and continuous peripheral nerve blocks is limited by short duration of analgesia and catheter-related complications, respectively. This double-blind, multicenter trial evaluated the efficacy, safety, and pharmacokinetics of single-injection, ultrasound-guided brachial plexus block (BPB) with liposomal bupivacaine (LB) added to a standardized pain management protocol for shoulder surgery. METHODS: Adults undergoing total shoulder arthroplasty or rotator cuff repair were randomized to receive LB 133 mg, LB 266 mg (pharmacokinetic and safety analyses only), or placebo, added to a standardized analgesia protocol. The primary end point was area under the curve (AUC) of visual analog scale pain intensity scores through 48 hours postsurgery. Secondary end points were total opioid consumption, percentage of opioid-free patients, and time to first opioid rescue through 48 hours. Pharmacokinetic samples were collected through 120 hours and on days 7 and 10. Adverse events were documented. RESULTS: One hundred fifty-five patients received treatment (LB 133 mg, N = 69; LB 266 mg, N = 15; placebo, N = 71). BPB with LB 133 mg was associated with significantly improved AUC of pain scores (least squares mean [SE] = 136.4 [12.09] vs 254.1 [11.77], P < 0.0001), opioid consumption (least squares mean [SE] = 12.0 [2.27] vs 54.3 [10.05] mg, P < 0.0001), median time to opioid rescue (4.2 vs 0.6 h, P < 0.0001), and percentage of opioid-free patients (treatment difference = 0.166, 95% confidence interval = 0.032-0.200, P = 0.008) through 48 hours vs placebo. Adverse event incidence was comparable between groups. CONCLUSIONS: Single-injection BPB with LB 133 mg provided analgesia through 48 hours postsurgery with reduced opioid use compared with placebo after shoulder surgery.

Transversus Abdominis Plane Block With Liposomal Bupivacaine for Pain After Cesarean Delivery in a Multicenter, Randomized, Double-Blind, Controlled Trial.

BACKGROUND: In women undergoing cesarean delivery under spinal anesthesia with intrathecal morphine, transversus abdominis plane (TAP) block with bupivacaine hydrochloride (HCl) may not improve postsurgical analgesia. This lack of benefit could be related to the short duration of action of bupivacaine HCl. A retrospective study reported that TAP block with long-acting liposomal bupivacaine (LB) reduced opioid consumption and improved analgesia following cesarean delivery. Therefore, we performed a prospective multicenter, randomized, double-blind trial examining efficacy and safety of TAP block with LB plus bupivacaine HCl versus bupivacaine HCl alone. METHODS: Women (n = 186) with term pregnancies undergoing elective cesarean delivery under spinal anesthesia were randomized (1:1) to TAP block with LB 266 mg plus bupivacaine HCl 50 mg or bupivacaine HCl 50 mg alone. Efficacy was evaluated in a protocol-compliant analysis (PCA) set that was defined a priori. The primary end point was total postsurgical opioid consumption (oral morphine equivalent dosing [MED]) through 72 hours. Pain intensity was measured using a visual analog scale. Adverse events (AEs) after treatment were recorded through day 14. RESULTS: Total opioid consumption through 72 hours was reduced with LB plus bupivacaine HCl versus bupivacaine HCl alone (least squares mean [LSM] [standard error (SE)] MED, 15.5 mg [6.67 mg] vs 32.0 mg [6.25 mg]). This corresponded to an LSM treatment difference of -16.5 mg (95% confidence interval [CI], -30.8 to -2.2 mg; P = .012). The area under the curve of imputed pain intensity scores through 72 hours supported noninferiority of LB plus bupivacaine HCl versus bupivacaine HCl alone (LSM [SE], 147.9 [21.13] vs 178.5 [19.78]; LSM treatment difference, -30.6; 95% CI, -75.9 to 14.7), with a prespecified noninferiority margin of 36 (P = .002). In an analysis of all treated patients, including those not meeting criteria for inclusion in the PCA, there was no difference in postsurgical opioid consumption between groups. In the LB plus bupivacaine HCl group, 63.6% of patients experienced an AE after treatment versus 56.2% in the bupivacaine HCl-alone group. Serious AEs after treatment were rare (≈3% in both groups). CONCLUSIONS: TAP block using LB plus bupivacaine HCl as part of a multimodal analgesia protocol incorporating intrathecal morphine resulted in reduced opioid consumption after cesarean delivery in the PCA set. Results suggest that with correct TAP block placement and adherence to a multimodal postsurgical analgesic regimen, there is an opioid-reducing benefit of adding LB to bupivacaine TAP blocks after cesarean delivery (ClinicalTrials.gov identifier: NCT03176459).

Multi-site Pain Is Associated with Long-term Patient-Reported Outcomes in Older Adults with Persistent Back Pain.

OBJECTIVE: To estimate the prevalence of co-occurring pain sites among older adults with persistent back pain and associations of multisite pain with longitudinal outcomes. DESIGN: Secondary analysis of a cohort study. SETTING: Three integrated health systems in the United States. SUBJECTS: Eight hundred ninety-nine older adults with persistent back pain. METHODS: Participants reported pain in the following sites: stomach, arms/legs/joints, headaches, neck, pelvis/groin, and widespread pain. Over 18 months, we measured back-related disability (Roland Morris, scored 0-24), pain intensity (11-point numerical rating scale), health-related quality of life (EuroQol-5D [EQ-5D], utility from 0-1), and falls in the past three weeks. We used mixed-effects models to test the association of number and type of pain sites with each outcome. RESULTS: Nearly all (N = 839, 93%) respondents reported at least one additional pain site. There were 216 (24%) with one additional site and 623 (69%) with multiple additional sites. The most prevalent comorbid pain site was the arms/legs/joints (N = 801, 89.1%). Adjusted mixed-effects models showed that for every additional pain site, RMDQ worsened by 0.65 points (95% confidence interval [CI] = 0.43 to 0.86), back pain intensity increased by 0.14 points (95% CI = 0.07 to 0.22), EQ-5D worsened by 0.012 points (95% CI = -0.018 to -0.006), and the odds of falling increased by 27% (odds ratio = 1.27, 95% CI = 1.12 to 1.43). Some specific pain sites (extremity pain, widespread pain, and pelvis/groin pain) were associated with greater long-term disability. CONCLUSIONS: Multisite pain is common among older adults with persistent back pain. Number of pain sites was associated with all outcomes; individual pain sites were less consistently associated with outcomes.

Using Natural Language Processing of Free-Text Radiology Reports to Identify Type 1 Modic Endplate Changes.

Electronic medical record (EMR) systems provide easy access to radiology reports and offer great potential to support quality improvement efforts and clinical research. Harnessing the full potential of the EMR requires scalable approaches such as natural language processing (NLP) to convert text into variables used for evaluation or analysis. Our goal was to determine the feasibility of using NLP to identify patients with Type 1 Modic endplate changes using clinical reports of magnetic resonance (MR) imaging examinations of the spine. Identifying patients with Type 1 Modic change who may be eligible for clinical trials is important as these findings may be important targets for intervention. Four annotators identified all reports that contained Type 1 Modic change, using N = 458 randomly selected lumbar spine MR reports. We then implemented a rule-based NLP algorithm in Java using regular expressions. The prevalence of Type 1 Modic change in the annotated dataset was 10%. Results were recall (sensitivity) 35/50 = 0.70 (95% confidence interval (C.I.) 0.52-0.82), specificity 404/408 = 0.99 (0.97-1.0), precision (positive predictive value) 35/39 = 0.90 (0.75-0.97), negative predictive value 404/419 = 0.96 (0.94-0.98), and F1-score 0.79 (0.43-1.0). Our evaluation shows the efficacy of rule-based NLP approach for identifying patients with Type 1 Modic change if the emphasis is on identifying only relevant cases with low concern regarding false negatives. As expected, our results show that specificity is higher than recall. This is due to the inherent difficulty of eliciting all possible keywords given the enormous variability of lumbar spine reporting, which decreases recall, while availability of good negation algorithms improves specificity.

A randomized trial of epidural glucocorticoid injections for spinal stenosis.

BACKGROUND: Epidural glucocorticoid injections are widely used to treat symptoms of lumbar spinal stenosis, a common cause of pain and disability in older adults. However, rigorous data are lacking regarding the effectiveness and safety of these injections. METHODS: In a double-blind, multisite trial, we randomly assigned 400 patients who had lumbar central spinal stenosis and moderate-to-severe leg pain and disability to receive epidural injections of glucocorticoids plus lidocaine or lidocaine alone. The patients received one or two injections before the primary outcome evaluation, performed 6 weeks after randomization and the first injection. The primary outcomes were the score on the Roland-Morris Disability Questionnaire (RMDQ, in which scores range from 0 to 24, with higher scores indicating greater physical disability) and the rating of the intensity of leg pain (on a scale from 0 to 10, with 0 indicating no pain and 10 indicating "pain as bad as you can imagine"). RESULTS: At 6 weeks, there were no significant between-group differences in the RMDQ score (adjusted difference in the average treatment effect between the glucocorticoid-lidocaine group and the lidocaine-alone group, -1.0 points; 95% confidence interval [CI], -2.1 to 0.1; P=0.07) or the intensity of leg pain (adjusted difference in the average treatment effect, -0.2 points; 95% CI, -0.8 to 0.4; P=0.48). A prespecified secondary subgroup analysis with stratification according to type of injection (interlaminar vs. transforaminal) likewise showed no significant differences at 6 weeks. CONCLUSIONS: In the treatment of lumbar spinal stenosis, epidural injection of glucocorticoids plus lidocaine offered minimal or no short-term benefit as compared with epidural injection of lidocaine alone. (Funded by the Agency for Healthcare Research and Quality; ClinicalTrials.gov number, NCT01238536.).

Predictors of Persistent Disability and Back Pain in Older Adults with a New Episode of Care for Back Pain.

Objective: To identify predictors of persistent disability and back pain in older adults. Design: Prospective cohort study. Setting: Back pain outcomes using longitudinal data registry. Subjects: Five thousand two hundred twenty adults age 65 years and older with a new primary care visit for back pain. Methods: Baseline measurements included: demographics, health, and back pain characteristics. We abstracted imaging findings from 348 radiology reports. The primary outcomes were the Roland-Morris Disability Questionnaire (RMDQ) and back pain intensity. We defined persistent disability as RMDQ of 4/24 or higher at both six and 12 months and persistent back pain as pain 3/10 or higher at both six and 12 months. Results: There were 2,498 of 4,143 (60.3%) participants with persistent disability, and 2,099 of 4,144 (50.7%) had persistent back pain. Adjusted analyses showed the following characteristics most strongly predictive of persistent disability and persistent back pain: sex, race, worse baseline clinical characteristics of back pain, leg pain, back-related disability and duration of symptoms, smoking, anxiety symptoms, depressive symptoms, a history of falls, greater number of comorbidities, knee osteoarthritis, wide-spread pain syndromes, and an index diagnosis of lumbar spinal stenosis. Within the imaging data subset, central spinal stenosis was not associated with disability or pain. Conclusion: We found that many predictors in older adults were similar to those for younger populations.

Effect of Comorbid Knee and Hip Osteoarthritis on Longitudinal Clinical and Health Care Use Outcomes in Older Adults With New Visits for Back Pain.

OBJECTIVE: To examine if a comorbid diagnosis of knee or hip osteoarthritis (OA) in older adults with new back pain visits is associated with long-term patient-reported outcomes and back-related health care use. DESIGN: Prospective cohort study. SETTING: Three integrated health systems forming the Back pain Outcomes using Longitudinal Data cohort. PARTICIPANTS: Participants (N=5155) were older adults (≥65y) with a new visit for back pain and a complete electronic health record data. INTERVENTIONS: Not applicable; we obtained OA diagnoses using diagnostic codes in the electronic health record 12 months prior to the new back pain visit. MAIN OUTCOME MEASURES: The Roland-Morris Disability Questionnaire (RDQ) and the EuroQol-5D (EQ-5D) were key patient-reported outcomes. Health care use, measured by relative-value units (RVUs), was summed for the 12 months after the initial visit. We used linear mixed-effects models to model patient-reported outcomes. We also used generalized linear models to test the association between comorbid knee or hip OA and total back-related RVUs. RESULTS: Of the 5155 participants, 368 (7.1%) had a comorbid knee OA diagnosis, and 94 (1.8%) had a hip OA diagnosis. Of the participants, 4711 (91.4%) had neither knee nor hip OA. In adjusted models, the 12-month RDQ score was 1.23 points higher (95% confidence interval [CI], 0.72-1.74) for patients with knee OA and 1.26 points higher (95% CI, 0.24-2.27) for those with hip OA than those without knee or hip OA, respectively. A lower EQ-5D score was found among participants with knee OA (.02 lower; 95% CI, -.04 to -.01) and hip OA diagnoses (.03 lower; 95% CI, -.05 to -.01) compared with those without knee or hip OA, respectively. Comorbid knee or hip OA was not significantly associated with total 12-month back-related resource use. CONCLUSIONS: Comorbid knee or hip OA in older adults with a new back pain visit was associated with modestly worse long-term disability and health-related quality of life.

Long-Term Effects of Repeated Injections of Local Anesthetic With or Without Corticosteroid for Lumbar Spinal Stenosis: A Randomized Trial.

OBJECTIVE: To determine the overall long-term effectiveness of treatment with epidural corticosteroid injections for lumbar central spinal stenosis and the effect of repeat injections, including crossover injections, on outcomes through 12 months. DESIGN: Multicenter, double-blind, randomized controlled trial comparing epidural injections of corticosteroid plus lidocaine versus lidocaine alone. SETTING: Sixteen clinical sites. PARTICIPANTS: Participants with imaging-confirmed lumbar central spinal stenosis (N=400). INTERVENTIONS: Participants were randomized to receive either epidural injections with corticosteroid plus lidocaine or lidocaine alone with the option of blinded crossover after 6 weeks to receive the alternate treatment. Participants could receive 1 to 2 injections from 0 to 6 weeks and up to 2 injections from 6 to 12 weeks. After 12 weeks, participants received usual care. MAIN OUTCOME MEASURES: Primary outcomes were the Roland-Morris Disability Questionnaire (RDQ) (range, 0-24, where higher scores indicate greater disability) and leg pain intensity (range, 0 [no pain] to 10 [pain as bad as you can imagine]). Secondary outcomes included opioid use, spine surgery, and crossover rates. RESULTS: At 12 months, both treatment groups maintained initial observed improvements, with no significant differences between groups on the RDQ (adjusted mean difference, -0.4; 95% confidence interval [CI], -1.6 to 0.9; P=.55), leg pain (adjusted mean difference, 0.1; 95% CI, -0.5 to 0.7; P=.75), opioid use (corticosteroid plus lidocaine: 41.4% vs lidocaine alone: 36.3%; P=.41), or spine surgery (corticosteroid plus lidocaine: 16.8% vs lidocaine alone: 11.8%; P=.22). Fewer participants randomized to corticosteroid plus lidocaine (30%, n=60) versus lidocaine alone (45%, n=90) crossed over after 6 weeks (P=.003). Among participants who crossed over at 6 weeks, the 6- to 12-week RDQ change did not differ between the 2 randomized treatment groups (adjusted mean difference, -1.0; 95% CI, -2.6 to 0.7; P=.24). In both groups, participants crossing over at 6 weeks had worse 12-month trajectories compared with participants who did not choose to crossover. CONCLUSIONS: For lumbar spinal stenosis symptoms, epidural injections of corticosteroid plus lidocaine offered no benefits from 6 weeks to 12 months beyond that of injections of lidocaine alone in terms of self-reported pain and function or reduction in use of opioids and spine surgery. In patients with improved pain and function 6 weeks after initial injection, these outcomes were maintained at 12 months. However, the trajectories of pain and function outcomes after 3 weeks did not differ by injectate type. Repeated injections of either type offered no additional long-term benefit if injections in the first 6 weeks did not improve pain.

Psychiatric Comorbidity Is Associated Prospectively with Diminished Opioid Analgesia and Increased Opioid Misuse in Patients with Chronic Low Back Pain.

BACKGROUND: Opioids are frequently prescribed for chronic low back pain (CLBP), but there are little prospective data on which patient subgroups may benefit. Psychiatric comorbidity, such as high levels of depression and anxiety symptoms (termed comorbid negative affect [NA]), is a common presentation and may predict diminished opioid analgesia and/or increased opioid misuse. METHODS: The authors conducted a 6½-month prospective cohort study of oral opioid therapy, with an active drug/placebo run-in period, in 81 CLBP patients with low, moderate, and high levels of NA. Treatment included an opioid titration phase with a prescribing physician blinded to NA group assignment and a 4-month continuation phase, during which subjects recorded daily pain levels using an electronic diary. The primary outcome was the percent improvement in average daily pain, summarized weekly. RESULTS: There was an overall 25% dropout rate. Despite the high NA group being prescribed a higher average daily dose of morphine equivalents, linear mixed model analysis revealed that the 24 study completers in each of the high NA and low NA groups had an average 21 versus 39% improvement in pain, respectively (P < 0.01). The high NA group also had a significantly greater rate of opioid misuse (39 vs. 8%, P < 0.05) and significantly more and intense opioid side effects (P < 0.01). CONCLUSIONS: These results indicate that the benefit and risk considerations in CLBP patients with high NA versus low NA are distinctly different. Thus, NA is an important phenotypic variable to characterize at baseline, before deciding whether to prescribe opioids for CLBP.

Multicenter survey of attitudes and perceptions of pain medicine fellows toward the use of lateral versus contralateral-oblique fluoroscopic view for interlaminar cervical epidural injection.

OBJECTIVE: For interlaminar cervical epidural steroid injections (CESI) the lateral fluoroscopic view (LAT) is often considered to improve needle localization. However, the contralateral-oblique view (CLO) is a useful alternative with potential advantages to improve identification of cervical anatomy and needle depth assessment. The authors explored the attitudes and perceptions of pain medicine fellows currently training in two ACGME-accredited pain medicine fellowship programs regarding the use of these two types of fluoroscopic views. METHODS: The survey was conducted online following a request by e-mail. Of a total of 20 fellows who were contacted, there were 17 respondents who had experience with both techniques, and they were included for analysis. RESULTS: The response rate for participation was 95%. Whereas 70.6% respondents reported they were very certain about the assessment of anatomy with the CLO view, only 17.6% felt very certain with the LAT view. Compared with learning to perform interlaminar CESI using the LAT view only, the majority of fellows thought that using the CLO technique was easier to learn (P < 0.01) and offered better visualization of contrast dye spread pattern to confirm the cervical epidural space (P = 0.013). All respondents perceived that the likelihood of interlaminar CESI complications would be lower with CLO technique. Overall, 82.4% of respondents considered CLO visualization as a preferred technique for interlaminar CESI. Respondents stated that the likelihood of using the CLO technique as an independent physician was significantly higher than using only the LAT technique (P < 0.001), particularly for patients who are obese and have short necks. CONCLUSIONS: For interlaminar CESI, using the CLO is perceived to provide better definition of anatomy and yet is easier to learn. Trainees may become more confident in performing interlaminar CESI with the CLO. We encourage all fellowship programs to include the CLO technique for interlaminar CESI as part of the training.

Association of early imaging for back pain with clinical outcomes in older adults.

IMPORTANCE: In contrast to the recommendations for younger adults, many guidelines allow for older adults with back pain to undergo imaging without waiting 4 to 6 weeks. However, early imaging may precipitate interventions that do not improve outcomes. OBJECTIVE: To compare function and pain at the 12-month follow-up visit among older adults who received early imaging with those who did not receive early imaging after a new primary care visit for back pain without radiculopathy. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort of 5239 patients 65 years or older with a new primary care visit for back pain (2011-2013) in 3 US health care systems. We matched controls 1:1 using propensity score matching of demographic and clinical characteristics, including diagnosis, pain severity, pain duration, functional status, and prior resource use. EXPOSURES: Diagnostic imaging (plain films, computed tomography [CT], magnetic resonance imaging [MRI]) of the lumbar or thoracic spine within 6 weeks of the index visit. PRIMARY OUTCOME: back or leg pain-related disability measured by the modified Roland-Morris Disability Questionnaire (score range, 0-24; higher scores indicate greater disability) 12 months after enrollment. RESULTS: Among the 5239 patients, 1174 had early radiographs and 349 had early MRI/CT. At 12 months, neither the early radiograph group nor the early MRI/CT group differed significantly from controls on the disability questionnaire. The mean score for patients who underwent early radiography was 8.54 vs 8.74 among the control group (difference, -0.10 [95% CI, -0.71 to 0.50]; mixed model, P = .36). The mean score for the early MRI/CT group was 9.81 vs 10.50 for the control group (difference,-0.51 [-1.62 to 0.60]; mixed model, P = .18). CONCLUSIONS AND RELEVANCE: Among older adults with a new primary care visit for back pain, early imaging was not associated with better 1-year outcomes. The value of early diagnostic imaging in older adults for back pain without radiculopathy is uncertain.

Back pain in seniors: the Back pain Outcomes using Longitudinal Data (BOLD) cohort baseline data.

BACKGROUND: Back pain represents a substantial burden globally, ranking first in a recent assessment among causes of years lived with disability. Though back pain is widely studied among working age adults, there are gaps with respect to basic descriptive epidemiology among seniors, especially in the United States. Our goal was to describe how pain, function and health-related quality of life vary by demographic and geographic factors among seniors presenting to primary care providers with new episodes of care for back pain. METHODS: We examined baseline data from the Back pain Outcomes using Longitudinal Data (BOLD) registry, the largest inception cohort to date of seniors presenting to a primary care provider for back pain. The sample included 5,239 patients ≥ 65 years old with a new primary care visit for back pain at three integrated health systems (Northern California Kaiser-Permanente, Henry Ford Health System [Detroit], and Harvard Vanguard Medical Associates [Boston]). We examined differences in patient characteristics across healthcare sites and associations of patient sociodemographic and clinical characteristics with baseline patient-reported measures of pain, function, and health-related quality of life. RESULTS: Patients differed across sites in demographic and other characteristics. The Detroit site had more African-American patients (50%) compared with the other sites (7-8%). The Boston site had more college graduates (68%) compared with Detroit (20%). Female sex, lower educational status, African-American race, and older age were associated with worse functional disability as measured by the Roland-Morris Disability Questionnaire. Except for age, these factors were also associated with worse pain. CONCLUSIONS: Baseline pain and functional impairment varied substantially with a number of factors in the BOLD cohort. Healthcare site was an important factor. After controlling for healthcare site, lower education, female sex, African-American race, and older age were associated with worse physical disability and all of these factors except age were associated with worse pain. TRIAL REGISTRATION: Clinical Trials.gov NCT01776242; Registration date: June 13, 2012.

Ketamine decreases postoperative pain scores in patients taking opioids for chronic pain: results of a prospective, randomized, double-blind study.

BACKGROUND: Patients prescribed opioids for chronic pain may suffer from inadequate postoperative pain control. Ketamine is an adjuvant demonstrating analgesic and opioid-sparing effects. We hypothesize that an intravenous ketamine infusion in addition to opioid-based patient-controlled analgesia (PCA) improves postoperative pain relief in this patient population. METHODS: We evaluated 64 patients with chronic pain taking opioids undergoing nononcologic surgery. Patients were randomized to receive either postoperative hydromorphone PCA and continuous ketamine (0.2 mg/kg/hour), or hydromorphone PCA and saline. Patients provided numeric rating scale (NRS) pain scores for "worst," "average," and "least" pain following surgery. The primary outcome measure was change in patients' postoperative NRS scores compared with baseline NRS. Secondary and tertiary outcomes included postoperative day one 24-hour opioid use and the amount of opioid used 24 hours prior to hospital discharge. RESULTS: Fifty-nine patients were included in the analysis. Baseline patient characteristics were similar with the exception of age. Patients using ketamine had decreased "average" pain scores (percent change between postoperative and preoperative NRS) after surgery (13.5% decrease in the ketamine group vs 15.5% increase in NRS in the placebo group, P = 0.0057). There were no differences in "worst" or "least" pain scores or postoperative opioid use. Side effects between groups were similar. CONCLUSIONS: Our study demonstrates that a postoperative ketamine infusion at 0.2 mg/kg/hour in addition to opioids results in a statistically significant reduction of "average" pain scores in patients undergoing surgery who take opioids for chronic pain. However, "least" and "worst" pain scores and the amount of opioid used postoperatively did not differ between groups. Thus, the use of a postoperative ketamine infusion at 0.2 mg/kg/hour provides limited benefit in improving pain management for this challenging population.

Study protocol- Lumbar Epidural steroid injections for Spinal Stenosis (LESS): a double-blind randomized controlled trial of epidural steroid injections for lumbar spinal stenosis among older adults.

BACKGROUND: Lumbar spinal stenosis is one of the most common causes of low back pain among older adults and can cause significant disability. Despite its prevalence, treatment of spinal stenosis symptoms remains controversial. Epidural steroid injections are used with increasing frequency as a less invasive, potentially safer, and more cost-effective treatment than surgery. However, there is a lack of data to judge the effectiveness and safety of epidural steroid injections for spinal stenosis. We describe our prospective, double-blind, randomized controlled trial that tests the hypothesis that epidural injections with steroids plus local anesthetic are more effective than epidural injections of local anesthetic alone in improving pain and function among older adults with lumbar spinal stenosis. METHODS: We will recruit up to 400 patients with lumbar central canal spinal stenosis from at least 9 clinical sites over 2 years. Patients with spinal instability who require surgical fusion, a history of prior lumbar surgery, or prior epidural steroid injection within the past 6 months are excluded. Participants are randomly assigned to receive either ESI with local anesthetic or the control intervention (epidural injections with local anesthetic alone). Subjects receive up to 2 injections prior to the primary endpoint at 6 weeks, at which time they may choose to crossover to the other intervention.Participants complete validated, standardized measures of pain, functional disability, and health-related quality of life at baseline and at 3 weeks, 6 weeks, and 3, 6, and 12 months after randomization. The primary outcomes are Roland-Morris Disability Questionnaire and a numerical rating scale measure of pain intensity at 6 weeks. In order to better understand their safety, we also measure cortisol, HbA1c, fasting blood glucose, weight, and blood pressure at baseline, and at 3 and 6 weeks post-injection. We also obtain data on resource utilization and costs to assess cost-effectiveness of epidural steroid injection. DISCUSSION: This study is the first multi-center, double-blind RCT to evaluate the effectiveness of epidural steroid injections in improving pain and function among older adults with lumbar spinal stenosis. The study will also yield data on the safety and cost-effectiveness of this procedure for older adults. TRIAL REGISTRATION: Clinicaltrials.gov NCT01238536.

Study protocol: the Back Pain Outcomes using Longitudinal Data (BOLD) registry.

BACKGROUND: Back pain is one of the most important causes of functional limitation, disability, and utilization of health care resources for adults of all ages, but especially among older adults. Despite the high prevalence of back pain in this population, important questions remain unanswered regarding the comparative effectiveness of commonly used diagnostic tests and treatments in the elderly. The overall goal of the Back pain Outcomes using Longitudinal Data (BOLD) project is to establish a rich, sustainable registry to describe the natural history and evaluate prospectively the effectiveness, safety, and cost-effectiveness of interventions for patients 65 and older with back pain. METHODS/DESIGN: BOLD is enrolling 5,000 patients ≥ 65 years old who present to a primary care physician with a new episode of back pain. We are recruiting study participants from three integrated health systems (Kaiser-Permanente Northern California, Henry Ford Health System in Detroit and Harvard Vanguard Medical Associates/ Harvard Pilgrim Health Care in Boston). Registry patients complete validated, standardized measures of pain, back pain-related disability, and health-related quality of life at enrollment and 3, 6 and 12 months later. We also have available for analysis the clinical and administrative data in the participating health systems' electronic medical records. Using registry data, we will conduct an observational cohort study of early imaging compared to no early imaging among patients with new episodes of back pain. The aims are to: 1) identify predictors of early imaging and; 2) compare pain, functional outcomes, diagnostic testing and treatment utilization of patients who receive early imaging versus patients who do not receive early imaging. In terms of predictors, we will examine patient factors as well as physician factors. DISCUSSION: By establishing the BOLD registry, we are creating a resource that contains patient-reported outcome measures as well as electronic medical record data for elderly patients with back pain. The richness of our data will allow better matching for comparative effectiveness studies than is currently possible with existing datasets. BOLD will enrich the existing knowledge base regarding back pain in the elderly to help clinicians and patients make informed, evidence-based decisions regarding their care.

Exploratory study of VVZ-149, a novel analgesic molecule, in the affective component of acute postoperative pain after laparoscopic colorectal surgery.

STUDY OBJECTIVE: VVZ-149 is a small molecule that inhibits the glycine transporter type 2 and the serotonin receptor 5-hydroxytryptamine 2A. In the present study, we investigated the efficacy and safety of VVZ-149 as a single-use injectable analgesic for treating moderate to severe postoperative pain after colorectal surgery. DESIGN: Randomized, parallel group, double-blind Phase 2 clinical trial (NCT02489526). SETTING: 3 academic institutions in the United States. PATIENTS: 60 patients undergoing laparoscopic colorectal surgery. INTERVENTIONS: A continuous 8-h intravenous infusion of VVZ-149 Injections (n = 40) or placebo (n = 20) administered after emergence from anesthesia. MEASUREMENTS: The outcome measures included pain intensity (PI), opioid consumption via patient-controlled analgesia (PCA), and rescue dosing provided "as needed". Early rescue dosing with opioids postoperatively was associated with preoperative negative affect (anxiety, depression, and pain catastrophizing), enabling it to be used as an indirect measure of the affective component of pain. Efficacy outcomes were compared between treatment groups based on preoperative negative affect and early rescue dosing of opioids. MAIN RESULTS: Postoperative PI was non-significantly lower in patients receiving VVZ-149 compared to those receiving placebo. The VVZ-149 group had a 34.2% reduction in opioid consumption for 24 h post-dose, along with fewer PCA demands. Somnolence and headache was higher in the intervention group. For patients characterized by high levels of preoperative negative affect, the VVZ-149 group experienced a significant pain reduction and 40% less opioid use compared to the placebo group. CONCLUSIONS: VVZ-149 resulted in a non-significant reduction of postoperative pain during the first 8 h after surgery. Post hoc analysis indicates that VVZ-149 may benefit patients with negative affect who otherwise have higher postoperative opioid use. REGISTRATION NUMBER: www.clinicaltrials.gov, ID: NCT02489526.

Randomized trial of transversus abdominis plane block with liposomal bupivacaine after cesarean delivery with or without intrathecal morphine.

STUDY OBJECTIVE: To investigate efficacy and safety of liposomal bupivacaine (LB) transversus abdominis plane (TAP) block with or without intrathecal morphine (ITM) compared with ITM alone for postsurgical analgesia after cesarean delivery (CD). DESIGN: Multicenter, open-label, randomized trial (NCT03853694). SETTING: Operating room. PATIENTS: Women with term pregnancy of 37 to 42 weeks scheduled for elective CD under spinal anesthesia. INTERVENTION: Patients were randomized 1:1:1 to LB 266 mg TAP block alone (LB group), ITM 50 µg followed by LB 266 mg TAP block (LB + ITM group), or ITM 150 µg alone (ITM group). All groups received the same postsurgical multimodal analgesic regimen. MEASUREMENTS: The LB and LB + ITM groups were compared with the ITM group for all efficacy outcomes. Postsurgical opioid consumption in morphine milligram equivalents (MMEs) through 72 h was compared by assessing noninferiority before testing superiority. Postsurgical pruritus severity was assessed on an 11-point numerical rating scale. MAIN RESULTS: Between March 4, 2019, and January 10, 2020, 153 patients (LB, n = 52; LB + ITM, n = 48; ITM, n = 53) were enrolled. Baseline characteristics were comparable across groups. The LB group had statistically noninferior postsurgical opioid consumption through 72 h compared with the ITM group (least squares mean [LSM], 19.2 vs 16.4 MMEs; LSM treatment ratio, 1.17 [95% confidence interval (CI), 0.74-1.86]; noninferiority P < 0.0034) as did the LB + ITM group (LSM, 14.6 vs 16.4 MMEs; LSM treatment ratio, 0.89 [95% CI, 0.55-1.44]; noninferiority P < 0.0001). The LB and LB + ITM groups had significantly reduced pruritus severity scores through 12, 24, 48, and 72 h compared with the ITM group (P ≤ 0.0121). Adverse events occurred in 58%, 85%, and 81% of the LB, LB + ITM, and ITM groups, respectively. CONCLUSIONS: LB TAP block with or without ITM resulted in statistically noninferior postsurgical opioid consumption through 72 h, reduced pruritus, and favorable safety compared with ITM in women undergoing CD.

Psychopathology predicts the outcome of medial branch blocks with corticosteroid for chronic axial low back or cervical pain: a prospective cohort study.

BACKGROUND: Comorbid psychopathology is an important predictor of poor outcome for many types of treatments for back or neck pain. But it is unknown if this applies to the results of medial branch blocks (MBBs) for chronic low back or neck pain, which involves injecting the medial branch of the dorsal ramus nerves that innervate the facet joints. The objective of this study was to determine whether high levels of psychopathology are predictive of pain relief after MBB injections in the lumbar or cervical spine. METHODS: This was a prospective cohort study. Consecutive patients in a pain medicine practice undergoing MBBs of the lumbar or cervical facets with corticosteroids were recruited to participate. Subjects were selected for a MBB based on operationalized selection criteria and the procedure was performed in a standardized manner. Subjects completed the Brief Pain Inventory (BPI) and the Hospital Anxiety and Depression Scale (HADS) just prior to the procedure and at one-month follow up. Scores on the HADS classified the subjects into three groups based on psychiatric symptoms, which formed the primary predictor variable: Low, Moderate, or High levels of psychopathology. The primary outcome measure was the percent improvement in average daily pain rating one-month following an injection. Analysis of variance and chi-square were used to analyze the analgesia and functional rating differences between groups, and to perform a responder analysis. RESULTS: Eighty six (86) subjects completed the study. The Low psychopathology group (n = 37) reported a mean of 23% improvement in pain at one-month while the High psychopathology group (n = 29) reported a mean worsening of -5.8% in pain (p < .001). Forty five percent (45%) of the Low group had at least 30% improvement in pain versus 10% in the High group (p < .001). Using an analysis of covariance, no baseline demographic, social, or medical variables were significant predictors of pain improvement, nor did they mitigate the effect of psychopathology on the outcome. CONCLUSION: Psychiatric comorbidity is associated with diminished pain relief after a MBB injection performed with steroid at one-month follow-up. These findings illustrate the importance of assessing comorbid psychopathology as part of a spine care evaluation.

Efficacy of dronabinol as an adjuvant treatment for chronic pain patients on opioid therapy.

UNLABELLED: We assessed the efficacy of dronabinol (Marinol capsules; Solvay Pharmaceuticals, Brussels, Belgium), a synthetic Delta(9)-THC (tetrahydrocannabinol), in 30 patients taking opioids for chronic pain to determine its potential analgesic effects as an adjuvant treatment. Phase I of this 2-phase study was a randomized, single-dose, double-blinded, placebo-controlled, crossover trial in which subjects were randomly administered either 10 mg or 20 mg of dronabinol or identical placebo capsules over the course of three, 8-hour visits. Baseline self-report measures, hourly ratings of pain intensity, pain relief, pain bothersomeness, treatment satisfaction, mood, side effects, and blood serum levels were obtained. Phase II was an extended open-label titrated trial of dronabinol as add-on medication to patients on stable doses of opioids. Results of the Phase I study showed that patients who received dronabinol experienced decreased pain intensity and increased satisfaction compared with placebo. No differences in benefit were found between the 20 mg and 10 mg doses. In the Phase II trial, titrated dronabinol contributed to significant relief of pain, reduced pain bothersomeness, and increased satisfaction compared with baseline. The incidence of side effects was dose-related. Overall, the use of dronabinol was found to result in additional analgesia among patients taking opioids for chronic noncancer pain. PERSPECTIVE: This study examines the effect of adding a cannabinoid to the regimen of patients with chronic pain who report significant pain despite taking stable doses of opioids. The results of our preliminary study suggest that dronabinol, a synthetic THC, may have an additive effect on pain relief.