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Objectives: This study compared the effects of leukocyte platelet-rich fibrin (L-PRF) and advanced platelet-rich fibrin (A-PRF) on patients' quality of life and the healing of palatal wounds after free gingival graft harvesting. Method and materials: After free gingival graft harvesting, palatal donor sites of 36 patients were assigned to one of three groups: L-PRF group, A-PRF group, or palatal stent + periodontal pack group (control group). Wound healing was evaluated by H2O2 test. Pain was evaluated by visual analog scale and number of analgesics consumed. For patient quality of life, the Oral Health Impact Profile-14 (OHIP-14) questionnaire was utilized. Results: Complete epithelialization was higher in the control group on day 7 than in the test groups (P < .05). Complete epithelialization was achieved in all groups 14 days postoperatively. Visual analog scale scores for pain and the number of analgesic tablets consumed were similar in all groups (P > .05). OHIP-14 total scores were similar in all study groups at 7 days postoperatively (P > .05). OHIP-14 total and physical pain score was lower in the L-PRF group than the A-PRF group at 14 days postoperatively (P < .05). Conclusion: Aside from the slight superiority of L-PRF over A-PRF, it can be concluded that both PRF procedures have similar effects on palatal wound healing and quality of life. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Decisions to prescribe opioids to patients depend on many factors, including illness severity, pain assessment, and patient age, race, ethnicity, and gender. Gender and sex disparities have been documented in many healthcare settings, but are understudied in inpatient general medicine hospital settings. OBJECTIVE: We assessed for differences in opioid administration and prescription patterns by legal sex in adult patient hospitalizations from the general medicine service at a large urban academic center. DESIGNS, SETTING, AND PARTICIPANTS: This study included all adult patient hospitalizations discharged from the acute care inpatient general medicine services at the University of California, San Francisco (UCSF) Helen Diller Medical Center at Parnassus Heights from 1/1/2013 to 9/30/2021. MAIN OUTCOME AND MEASURES: The primary outcomes were (1) average daily inpatient opioids received and (2) days of opioids prescribed on discharge. For both outcomes, we first performed logistic regression to assess differences in whether or not any opioids were administered or prescribed. Then, we performed negative binomial regression to assess differences in the amount of opioids given. We also performed all analyses on a subgroup of hospitalizations with pain-related diagnoses. RESULTS: Our study cohort included 48,745 hospitalizations involving 27,777 patients. Of these, 24,398 (50.1%) hospitalizations were female patients and 24,347 (49.9%) were male. Controlling for demographic, clinical, and hospitalization-level variables, female patients were less likely to receive inpatient opioids compared to male patents (adjusted OR 0.87; 95% CI 0.82, 0.92) and received 27.5 fewer morphine milligram equivalents per day on average (95% CI - 39.0, - 16.0). When considering discharge opioids, no significant differences were found between sexes. In the subgroup analysis of pain-related diagnoses, female patients received fewer inpatient opioids. CONCLUSIONS: Female patients were less likely to receive inpatient opioids and received fewer opioids when prescribed. Future work to promote equity should identify strategies to ensure all patients receive adequate pain management.

The μ-opioid receptor (μOR), a prototypical G protein-coupled receptor (GPCR), is the target of opioid analgesics such as morphine and fentanyl. Due to the severe side effects of current opioid drugs, there is considerable interest in developing novel modulators of μOR function. Most GPCR ligands today are small molecules, however biologics, including antibodies and nanobodies, represent alternative therapeutics with clear advantages such as affinity and target selectivity. Here, we describe the nanobody NbE, which selectively binds to the μOR and acts as an antagonist. We functionally characterize NbE as an extracellular and genetically encoded μOR ligand and uncover the molecular basis for μOR antagonism by determining the cryo-EM structure of the NbE-μOR complex. NbE displays a unique ligand binding mode and achieves μOR selectivity by interactions with the orthosteric pocket and extracellular receptor loops. Based on a β-hairpin loop formed by NbE that deeply protrudes into the μOR, we design linear and cyclic peptide analogs that recapitulate NbEs antagonism. The work illustrates the potential of nanobodies to uniquely engage with GPCRs and describes lower molecular weight μOR ligands that can serve as a basis for therapeutic developments.

INTRODUCTION: Opioids are commonly prescribed to patients with chronic liver disease, but little is known regarding medication prescribing patterns of hepatologists. Opioid use increased until national guidelines limited opioid prescriptions in early 2016. We aimed to describe rates of opioid and nonopioid analgesics to Medicare beneficiaries by hepatologists from 2013 to 2017 and identify demographic characteristics associated with higher prescribing. METHODS: Prescription data from 2013 to 2017 by 761 hepatologists identified in the Centers for Medicare and Medicaid Services Part D Public Use File were analyzed. Annual prescription volumes were compared for providers with >10 annual prescriptions of a given drug type. Provider characteristics associated with opioid prescriptions were identified through multivariate logistic regression analyses. RESULTS: The proportion of hepatologists prescribing >10 annual opioid prescriptions decreased from 29% to 20.6%. Median annual opioid prescriptions per hepatologist significantly decreased from 24 to 20. Tramadol remained the most prescribed analgesic. Nonopioid analgesic prescription volume did not increase significantly. Provider characteristics associated with increased opioid prescriptions included male sex, practice location in the South and Midwest (vs West), more years in practice, and a greater proportion of beneficiaries who are white or with low-income subsidy claims. Characteristics associated with fewer prescriptions included non-university-based practice, having a greater proportion of female beneficiaries, and later prescription year. DISCUSSION: Hepatologists are prescribing less opioids. However, the prevalence of tramadol use and the lack of increase in nonopioid analgesic use highlights the need for advancing the science and training of pain management in chronic liver disease and targeted implementation of nonopioid treatment programs.

BackgroundPain is ubiquitous, yet understudied. The objective of this study was to analyze inequities in pain assessment and management for hospitalized older adults focusing on demographic and geriatric-related variables.MethodsThis was a retrospective cohort study from January 2013 through September 2021 of all adults 65 years or older on the general medicine service at UCSF Medical Center. Primary exposures included (1) demographic variables including race/ethnicity and limited English proficiency (LEP) status and (2) geriatric-related variables including age, dementia or mild cognitive impairment diagnosis, hearing or visual impairment, end-of-life care, and geriatrics consult involvement. Primary outcomes included (1) adjusted odds of numeric pain assessment versus other assessments and (2) adjusted opioids administered, measured by morphine milligram equivalents (MME).ResultsA total of 15,809 patients were included across 27,857 hospitalizations with 1,378,215 pain assessments, with a mean age of 77.8 years old. Patients were 47.4% White, 26.3% with LEP, 49.6% male, and 50.4% female. Asian (OR 0.75, 95% CI 0.70-0.80), Latinx (OR 0.90, 95% CI 0.83-0.99), and Native Hawaiian or Pacific Islander (OR 0.77, 95% CI 0.64-0.93) patients had lower odds of a numeric assessment, compared with White patients. Patients with LEP (OR 0.70, 95% CI 0.66-0.74) had lower odds of a numeric assessment, compared with English-speaking patients. Patients with dementia, hearing impairment, patients 75+, and at end-of-life were all less likely to receive a numeric assessment. Compared with White patients (86 MME, 95% CI 77-96), Asian patients (55 MME, 95% CI 46-65) received fewer opioids. Patients with LEP, dementia, hearing impairment and those 75+ years old also received significantly fewer opioids.ConclusionOlder, hospitalized, general medicine patients from minoritized groups and with geriatric-related conditions are uniquely vulnerable to inequitable pain assessment and management. These findings raise concerns for pain underassessment and undertreatment.

BACKGROUND: Percutaneous auricular nerve stimulation (neuromodulation) involves implanting electrodes around the ear and administering an electric current. A device is currently available within the USA cleared to treat symptoms from opioid withdrawal, and multiple reports suggest a possible postoperative analgesic effect. The current randomized controlled pilot study was undertaken to (1) determine the feasibility and optimize the protocol for a subsequent definitive clinical trial; and (2) estimate the treatment effect of auricular neuromodulation on postoperative pain and opioid consumption following two ambulatory surgical procedures. METHODS: Within the recovery room following cholecystectomy or hernia repair, an auricular neuromodulation device (NSS-2 Bridge, Masimo, Irvine, California, USA) was applied. Participants were randomized to 5 days of either electrical stimulation or sham in a double-blinded fashion. RESULTS: In the first 5 days, the median (IQR) pain level for active stimulation (n=15) was 0.6 (0.3-2.4) vs 2.6 (1.1-3.7) for the sham group (n=15) (p=0.041). Concurrently, the median oxycodone use for the active stimulation group was 0 mg (0-1), compared with 0 mg (0-3) for the sham group (p=0.524). Regarding the highest pain level experienced over the entire 8-day study period, only one participant (7%) who received active stimulation experienced severe pain, versus seven (47%) in those given sham (p=0.031). CONCLUSIONS: Percutaneous auricular neuromodulation reduced pain scores but not opioid requirements during the initial week after cholecystectomy and hernia repair. Given the ease of application as well as a lack of systemic side effects and reported complications, a definitive clinical trial appears warranted. TRIAL REGISTRATION NUMBER: NCT05521516.

INTRODUCTION: Post-operative prescription opioid use is a known risk factor for persistent opioid use. Despite the increased utilization of robotic-assisted surgery (RAS) for inguinal hernia repair (IHR), little is known whether this minimally invasive approach results in less opioid consumption. In this study, we compare long-term opioid use between RAS versus laparoscopic (Lap) versus open surgery for IHR. METHODS: A retrospective cohort study of opioid-naïve patients who underwent outpatient primary IHR was conducted using the Merative™ MarketScan® (Previously IBM MarketScan®) Databases between 2016 and 2020. Patients not continuously enrolled 180 days before/after surgery, who had malignancy, pre-existing chronic pain, opioid dependency, or invalid prescription fill information were excluded. Among patients exposed to opioids peri-operatively, we assessed long-term opioid use as any opioid prescription fill within 90 to 180 days post-surgery. Secondary outcomes were controlled substance schedule II/III opioid fill, and high-dose opioid fill defined as > 50 morphine milligram equivalent per day. An Inverse-probability of treatment weighted logistic regression was used to compare outcomes between groups with p-value of

Objectives: This study examined the impact of injectable plateletrich fibrin (iPRF) and concentrated growth factor on postoperative pain, edema, trismus, and quality of life in impacted mandibular third molar surgery. The primary aim of this study was to minimize common sequelae following third molar surgery by using iPRF and concentrated growth factor. The secondary objective was to compare the postoperative effects of these products. Method and materials: This study represents a single-center, randomized prospective clinical trial conducted at the Ordu University Faculty of Dentistry. It involved patients who underwent third molar surgery for various reasons between July and October 2022. The predictor variables were the use of concentrated growth factor and i-PRF. They were categorized as concentrated growth factor, i-PRF, and control groups. The outcome variables include pain levels and analgesic consumption measured on a visual analog scale, distances between predetermined anatomical points, maximum mouth opening capacity, and data from the postoperative symptom severity (PoSSe) scale. Some statistical tests were performed with a 95% confidence interval, which was considered significant. Results: Total analgesic use was notably lower in the concentrated growth factor group (P = .044). Concentrated growth factor and iPRF outperformed the control group in all edema measurements by postoperative day 7 (tragus–pogonion, lateral canthus–angulus, tragus–commissura; P < .05). Concentrated growth factor significantly reduced trismus on days 2 and 7. Quality of life was notably higher in the concentrated growth factor group than in the control group (P = .026), although iPRF group differences were not significant. Conclusion: The results indicate that concentrated growth factor has a limited impact on postoperative pain, but significantly reduces edema, trismus, and enhances quality of life. The iPRF group experienced positive effects on pain, edema, and trismus, although the statistically significant differences observed with concentrated growth factor highlight its potential for use instead of iPRF after third molar surgery. An increased sample size is essential for more comprehensive results [ABSTRACT FROM AUTHOR]

Objective: Currently, there is no established treatment protocol to treat interdental papillary loss. This research aimed to evaluate the outcomes of interdental papillary reconstruction using minimally invasive surgery, with injectable hyaluronic acid gel. Method and materials: Seventeen patients were included, each with five sites of class 1 papillary recession (40 sites in the maxilla and 45 sites in the mandible). Subperiosteal tunneling was performed through a horizontal incision made apical to the base of the papilla without penetrating it. The free gingival sulcus was sealed by 000 retraction cord. A total of 0.2 to 0.6 mL hyaluronic acid was injected gradually. The incision was sutured with poly-glycolic sutures. Treated sites underwent clinical and digital evaluation at three follow-up time points (1 month, 3 months, and 6 months). Results: The interdental papillary defect height in the maxillary sites significantly reduced by 60%, 66%, and 42% at 1,3, and 6 months, respectively. In mandibular sites, the reduction was 54%, 55%, and 40% at the same follow-up time points. Regarding interdental papillary defect surface area in the maxilla, the reduction was 65%, 71%, and 45% at 1, 3, and 6 months. In the mandible, a reduction of 60%, 64%, and 48% was noticed at the same time points. Regarding patients' pain level score, during the day of surgery, 16 patients reported pain; the average pain score out of 10 was 3.94, and 11 patients (64.7%) needed to take analgesics. The pain generally subsided in the following days. At the day of treatment, 12 out of the 17 patients (70.6%) reported mild difficulty in speaking and eating. No complication, hypersensitivity, or allergy was noted in any patient. Conclusion: Subperiosteal tunneling with hyaluronic acid injection demonstrates clinical improvements in papilla height and papillary recession surface area reduction after 3 months of follow-up, with reduction in improvement after 6 months. Clinical significance: Adjunctive use of hyaluronic acid injection with minimally invasive surgery in interdental papillary management may improve clinical and esthetic outcomes. [ABSTRACT FROM AUTHOR]

Pain and inflammation contribute immeasurably to reduced quality of life, yet modern analgesic and anti-inflammatory therapeutics can cause dependence and side effects. Here, we screened 1444 plant extracts, prepared primarily from native species in California and the United States Virgin Islands, against two voltage-gated K+ channels - T-cell expressed Kv1.3 and nociceptive-neuron expressed Kv7.2/7.3. A subset of extracts both inhibits Kv1.3 and activates Kv7.2/7.3 at hyperpolarized potentials, effects predicted to be anti-inflammatory and analgesic, respectively. Among the top dual hits are witch hazel and fireweed; polymodal modulation of multiple K+ channel types by hydrolysable tannins contributes to their dual anti-inflammatory, analgesic actions. In silico docking and mutagenesis data suggest pore-proximal extracellular linker sequence divergence underlies opposite effects of hydrolysable tannins on different Kv1 isoforms. The findings provide molecular insights into the enduring, widespread medicinal use of witch hazel and fireweed and demonstrate a screening strategy for discovering dual anti-inflammatory, analgesic small molecules.

OBJECTIVE: To evaluate the role of psychosocial well-being on perioperative pain and opioid use among patients with cleft lip and palate (CLP) undergoing alveolar bone grafting (ABG). DESIGN: Retrospective review. SETTING: Tertiary level craniofacial clinic. PARTICIPANTS: 34 patients with CLP (median age: 11.7 years), including 25 (73.5%) unilateral CLP and 9 (26.5%) bilateral CLP, who underwent ABG from 2015 to 2022. INTERVENTIONS: ABG using iliac crest bone graft. Patients were prospectively administered four patient-reported psychosocial instruments from the Patient-Reported Outcomes Measurement Information System. MAIN OUTCOME MEASURES: Perioperative opioid use in morphine equivalent dosage/kilogram, patient-reported pain scores, and length of hospital stay after ABG. RESULTS: Patient-reported anxiety (r = 0.41, p = 0.02) and depressive symptoms (r = 0.35, p = 0.04) correlated to higher perioperative opioid usage. Multivariable regression models including psychosocial scores, total acetaminophen usage, length of surgery, and other simultaneous surgeries were developed for total opioid usage, patient-reported pain, and length of hospital stay. Patient-reported anxiety was independently predictive of higher perioperative opioid use (β=0.36, p = 0.01) and higher pain scores (β=0.39, p = 0.02), but not length of hospital stay. CONCLUSIONS: We identified an association for patient-reported anxiety and perioperative opioid use and pain in a CLP cohort undergoing ABG. Future considerations in preoperative patient and family consultation may be indicated in patients self-reporting higher anxiety in an effort to minimize perioperative opioid usage.

The intensifying global opioid crisis, majorly attributed to fentanyl (FT) and its analogs, has necessitated the development of rapid and ultrasensitive remote/on-site FT sensing modalities. However, current approaches for tracking FT exposure through wastewater-based epidemiology (WBE) are unadaptable, time-consuming, and require trained professionals. Toward developing an extended in situ wastewater opioid monitoring system, we have developed a screen-printed electrochemical FT sensor and integrated it with a customized submersible remote sensing probe. The sensor composition and design have been optimized to address the challenges for extended in situ FT monitoring. Specifically, ZIF-8 metal-organic framework (MOF)-derived mesoporous carbon (MPC) nanoparticles (NPs) are incorporated in the screen-printed carbon electrode (SPCE) transducer to improve FT accumulation and its electrocatalytic oxidation. A rapid (10 s) and sensitive square wave voltammetric (SWV) FT detection down to 9.9 µgL-1 is thus achieved in aqueous buffer solution. A protective mixed-matrix membrane (MMM) has been optimized as the anti-fouling sensor coating to mitigate electrode passivation by FT oxidation products and enable long-term, intermittent FT monitoring. The unique MMM, comprising an insulating polyvinyl chloride (PVC) matrix and carboxyl-functionalized multi-walled carbon nanotubes (CNT-COOH) as semiconductive fillers, yielded highly stable FT sensor operation (> 95% normalized response) up to 10 h in domestic wastewater, and up to 4 h in untreated river water. This sensing platform enables wireless data acquisition on a smartphone via Bluetooth. Such effective remote operation of submersible opioid sensing probes could enable stricter surveillance of community water systems toward timely alerts, countermeasures, and legal enforcement.

BACKGROUND: The pleiotropic effects of the melanocortin system show promise in overcoming limitations associated with large variations in opioid analgesic effectiveness observed in equine practice. Of particular interest is variation in the melanocortin-1-receptor (MC1R) gene, which dictates pigment type expression through its epistatic interaction with the agouti signalling protein (ASIP) gene. MC1R has previously been implicated in opioid efficacy in other species; however, this relationship is yet to be explored in horses. In this study, analgesic effectiveness was scored (1-3) based on noted response to dura penetration during the performance of cerebrospinal fluid centisis after sedation and tested for association with known genetic regions responsible for pigmentation variation in horses. RESULTS: The chestnut phenotype was statistically significant (P < 0.05) in lowering analgesic effectiveness when compared to the bay base coat colour. The 11bp indel in ASIP known to cause the black base coat colour was not significant (P>0.05); however, six single nucleotide polymorphisms (SNPs) within the genomic region encoding the ASIP gene and one within MC1R were identified as being nominally significant (P

BACKGROUND: Patients with limited English proficiency (LEP) may have worse health outcomes and differences in processes of care. Language status may particularly affect situations that depend on communication, such as symptom management or end-of-life (EOL) care. OBJECTIVE: The objective of this study was to assess whether opioid prescribing and administration differs by English proficiency (EP) status among hospitalized patients receiving EOL care. METHODS: This single-center retrospective study identified all adult patients receiving comfort care on the general medicine service from January 2013 to September 2021. We assessed for differences in the quantity of opioids administered (measured by oral morphine equivalents [OME]) by patient LEP status using multivariable linear regression, controlling for other patient and medical factors. RESULTS: We identified 2652 patients receiving comfort care at our institution during the time period, of whom 1813 (68%) died during the hospitalization. There were no significant differences by LEP status in terms of mean OME per day (LEP received 30.8 fewer OME compared to EP, p = .91) or in the final 24 h before discharge (LEP received 61.7 more OME compared to EP, p = .80). CONCLUSION: LEP was not associated with differences in the amount of opioids received for patients whose EOL management involved standardized order sets for symptom management at our hospital.

BACKGROUND: The number of older adults entering opioid treatment programs (OTPs) to treat opioid use disorder (OUD) is increasing. However, the lived experiences of aging in OTPs have not been examined. OBJECTIVE: To explore the aging experience with OUD and barriers to medical care for older adults who receive care in OTPs. DESIGN: From November 2021 to July 2022, we conducted 1-to-1, semi-structured qualitative interviews in English and Spanish, audio-recorded, transcribed, systematically coded, and analyzed to identify key themes regarding the challenges of aging with OUD and managing chronic diseases. PARTICIPANTS: Thirty-six adults aged ≥ 55 enrolled in OTPs in San Diego, California. APPROACH: A descriptive qualitative approach was used. Major themes and subthemes were identified through thematic analysis until thematic saturation was reached. KEY RESULTS: All participants were on methadone and had a mean age of 63.4 (SD 5.1) years; 11 (30.6%) identified as female, 14 (39%) as Hispanic/Latino, and 11 (36%) as Black, with a mean duration of methadone treatment of 5.6 years. Chronic diseases were common, with 21 (58.3%) reporting hypertension, 9 (25%) reporting untreated hepatitis C, and 32 (88.9%) having ≥ 2 chronic diseases. Three major themes emerged: (1) avoidance of medical care due to multiple intersectional stigmas, including those related to drug use, substance use disorder (SUD) treatment, ageism, and housing insecurity; (2) increasing isolation with aging and loss of family and peer groups; (3) the urgent need for integrating medical and aging-focused care with OUD treatment in the setting of increasing health and functional challenges. CONCLUSIONS: Older adults with OUD reported increasing social isolation and declining health while experiencing multilevel stigma and discrimination. The US healthcare system must transform to deliver age-friendly care that integrates evidence-based geriatric models of care incorporated with substance use disorder treatment and addresses the intersectional stigma this population has experienced in healthcare settings.

Background and Aims: Anterior cruciate ligament (ACL) repair is a common sports-related surgery requiring early rehabilitation. Injection between the popliteal artery and the capsule of the knee (iPACK) provides analgesia to the posterior knee and, when combined with adductor canal block (ACB), can provide complete analgesia for knee surgery. A 4-in-1 block, a single injection, has been studied for analgesia in TKR but not ACL repair. This study was done with the objective of comparing the postoperative analgesia of iPACK + ACB versus 4-in-1 block in ACL repair. Methods: The study was conducted on 184 participants undergoing ACL repair in the age group of 18-70 years. Patients were randomly allocated to iPACK +ACB or 4-in-1 block. After the preoperative and intraoperative protocol, a guided nerve block was performed. The duration of motor blockade of spinal anaesthesia and pain scores were monitored using the visual analogue scale (VAS), and the time for first rescue analgesia was noted at 3, 6, 12, 24, and 36 hours. An independent sample t-test was used to find the association of all quantitative variables, and a Chi-square test was used to find the association of categorical variables with both groups of patients (P < 0.05). Results: VAS scores were statistically similar between the two groups at 3, 6, 12, and 24 hours but were significantly less at 36 hours in group B (P < 0.001). The time to perform the regional block was lower in group B, a single injection technique (P < 0.001). None of the patients showed muscle weakness in the postoperative period and could cooperate reasonably with physiotherapy. Conclusion: The 4-in-1 block provides non-inferior analgesia compared to the established iPACK plus ACB for arthroscopic ACL surgery. Keywords: Analgesia, anterior cruciate ligament, muscle weakness, nerve block, visual analog scale, Author(s): Ritesh Roy [1]; Gaurav Agarwal (corresponding author) [2]; Priyanka Ahuja [3]; Ankita Mohta [2] INTRODUCTION Anterior cruciate ligament (ACL) injury, the most common sports-related injury of the knee, has [...]

The New Zealand white rabbit (Oryctolagus cuniculus) is a frequently used surgical model. Pain management after surgery is a critical aspect of animal welfare. Recently, a long-acting buprenorphine formulation (Ethiqa XR; EXR) was approved for use in rats and mice but has not yet been investigated in rabbits. The current study aimed to determine whether a single subcutaneous dose of 0.15mg/kg of EXR could achieve and maintain therapeutic buprenorphine plasma concentrations (0.1ng/mL) for 72h in male and female rabbits. We also evaluated the safety profiles of EXR and the fentanyl patch (FP) by assessing fecal output after surgery, because opioids are known to decrease intestinal motility. Behavior and pain scores were compared for rabbits that received either EXR or the FP after undergoing an annulus puncture procedure to induce osteoarthritis. EXR at 0.15mg/kg SC provided a shorter time to onset and sustained analgesia for 72h in male and female rabbits, whereas the FP provided suboptimal analgesia after 48h. Both EXR and FP reduced fecal output after surgery. Output returned to baseline levels within 72h for the EXR group and remained slightly below baseline at 96h after surgery for the fentanyl group. Grimace pain scores revealed no significant difference between treatment groups. These results suggest that EXR is a safe and effective option for postoperative pain management in rabbits.

OBJECTIVES: Patients receiving chiropractic spinal manipulation (CSM) for low back pain (LBP) are less likely to receive any opioid prescription for subsequent pain management. However, the likelihood of specifically being prescribed tramadol, a less potent opioid, has not been explored. We hypothesised that adults receiving CSM for newly diagnosed radicular LBP would be less likely to receive a tramadol prescription over 1-year follow-up, compared with those receiving usual medical care. DESIGN: Retrospective cohort study. SETTING: US medical records-based dataset including >115 million patients attending academic health centres (TriNetX, Inc), queried 9 November 2023. PARTICIPANTS: Opioid-naive adults aged 18-50 with a new diagnosis of radicular LBP were included. Patients with serious pathology and tramadol use contraindications were excluded. Variables associated with tramadol prescription were controlled via propensity matching. INTERVENTIONS: Patients were divided into two cohorts dependent on treatment received on the index date of radicular LBP diagnosis (CSM or usual medical care). PRIMARY AND SECONDARY OUTCOME MEASURES: Risk ratio (RR) for tramadol prescription (primary); markers of usual medical care utilisation (secondary). RESULTS: After propensity matching, there were 1171 patients per cohort (mean age 35 years). Tramadol prescription was significantly lower in the CSM cohort compared with the usual medical care cohort, with an RR (95% CI) of 0.32 (0.18 to 0.57; p

PURPOSE: The pupil displays chaotic oscillations, also referred to as pupillary unrest in ambient light (PUAL). As pain has previously been shown to increase pupillary unrest, the quantitative assessment of PUAL has been considered a possible tool to identify and quantify pain. Nevertheless, PUAL is affected by various states, such as vigilance, cognitive load, or emotional arousal, independent of pain. Furthermore, systematically applied opioids are known to reduce PUAL, thus potentially limiting its usefulness to detect pain or changes in pain intensity. To test the hypothesis that PUAL can reliably identify changes in pain intensity in a clinical setting, we measured PUAL in patients experiencing substantial pain relief when regional anesthesia interventions were applied after surgery. METHODS: We conducted an observational study at an academic surgery centre following institutional review board approval. Eighteen patients with unsatisfactory pain control following surgery underwent regional anesthesia procedures to improve pain control. We used infrared pupillometry to assess pupillary unrest before and after the regional block. We then compared the changes in pupillary unrest with the changes in pain scores (numeric rating scale [NRS], range 0-10). RESULTS: Eighteen patients received epidural anesthesia (n = 14) or peripheral nerve blocks (n = 4), resulting in improvement of mean (standard deviation [SD]) NRS pain scores from 7.2 (1.7) to 1.9 (1.8) (difference in means, -2.2; 95% confidence interval [CI], -6.3 to -4.1; P

The supraspinal descending pain modulatory system (DPMS) shapes pain perception via monoaminergic modulation of sensory information in the spinal cord. However, the role and synaptic mechanisms of descending noradrenergic signaling remain unclear. Here, we establish that noradrenergic neurons of the locus coeruleus (LC) are essential for supraspinal opioid antinociception. While much previous work has emphasized the role of descending serotonergic pathways, we find that opioid antinociception is primarily driven by excitatory output from the ventrolateral periaqueductal gray (vlPAG) to the LC. Furthermore, we identify a previously unknown opioid-sensitive inhibitory input from the rostroventromedial medulla (RVM), the suppression of which disinhibits LC neurons to drive spinal noradrenergic antinociception. We describe pain-related activity throughout this circuit and report the presence of prominent bifurcating outputs from the vlPAG to the LC and the RVM. Our findings substantially revise current models of the DPMS and establish a supraspinal antinociceptive pathway that may contribute to multiple forms of descending pain modulation.

BACKGROUND: Buprenorphine is an effective treatment for opioid use disorder (OUD); however, buprenorphine initiation can be complicated by withdrawal symptoms including precipitated withdrawal. There has been increasing interest in using low dose initiation (LDI) strategies to reduce this withdrawal risk. As there are limited data on withdrawal symptoms during LDI, we characterize withdrawal symptoms in people with daily fentanyl use who underwent initiation using these strategies as outpatients. METHODS: We conducted a retrospective chart review of patients with OUD using daily fentanyl who were prescribed 7-day or 4-day LDI at 2 substance use disorder treatment clinics in San Francisco. Two addiction medicine experts assessed extracted chart documentation for withdrawal severity and precipitated withdrawal, defined as acute worsening of withdrawal symptoms immediately after taking buprenorphine. A third expert adjudicated disagreements. Data were analyzed using descriptive statistics. RESULTS: There were 175 initiations in 126 patients. The mean age was 37 (SD 10 years). 71% were men, 26% women, and 2% non-binary. 21% identified as Black, 16% Latine, and 52% white. 60% were unstably housed and 75% had Medicaid insurance. Substance co-use included 74% who used amphetamines, 29% cocaine, 22% benzodiazepines, and 19% alcohol. Follow up was available for 118 (67%) initiations. There was deviation from protocol instructions in 22% of these initiations with follow up. 31% had any withdrawal, including 21% with mild symptoms, 8% moderate and 2% severe. Precipitated withdrawal occurred in 10 cases, or 8% of initiations with follow up. Of these, 7 had deviation from protocol instructions; thus, there were 3 cases with follow up (3%) in which precipitated withdrawal occurred without protocol deviation. CONCLUSIONS: Withdrawal was relatively common in our cohort but was mostly mild, and precipitated withdrawal was rare. Deviation from instructions, structural barriers, and varying fentanyl use characteristics may contribute to withdrawal. Clinicians should counsel patients who use fentanyl that mild withdrawal symptoms are likely during LDI, and there is still a low risk for precipitated withdrawal. Future studies should compare withdrawal across initiation types, seek ways to support patients in initiating buprenorphine, and qualitatively elicit patients withdrawal experiences.