Patients with chronic pain

Predictive Factors of Postoperative Pain in Patients With Tibiotalocalcaneal Arthrodesis With an Intramedullary Nail: A Retrospective Review

Tibiotalocalcaneal arthrodesis has been shown in literature to have good results in regards to low complication rates and deformity correction. While previous studies have investigated functional outcomes and complication rates, no large-scale studies have looked at pain outcomes. The present study performed a retrospective review of 154 extremities to analyze how a patient's comorbidities and characteristics influence pain outcomes following a tibiotalocalcaneal arthrodesis. The present study found an average change of pain from 7.1 to 3.0 in at least a 6 month follow up. We found that a diagnosis of chronic pain and tobacco use had statistically significant less pain improvement compared to patients without chronic pain or current tobacco use. We determined no statistically significant difference in pain outcomes for patients with or without Charcot deformity. Lastly, we found that with older patients there was more pain improvement observed. We physicians can educate current tobacco users of the improved pain outcomes with tobacco cessation prior to surgery. We recommend a multidisciplinary approach for pain in patients with a pre-operative diagnosis of chronic pain and to educate patients on realistic postoperative pain outcomes.

The α2,3-selective potentiators of GABAA receptors, KRM-II-81 and MP-III-80, produce anxiolytic-like effects and block chemotherapy-induced hyperalgesia in mice without tolerance development

Opiate analgesics are one of the treatment options for severe chronic pain, including late-stage cancer, chronic back pain and other disorders. The recent resurgence in opioid overdose has highlighted the serious need for alternative medicines for pain management. While a role for potentiators of α2/3-containing GABA_A receptors in the modulation of pain has been known for several years, advancements in this area required data from selective compounds. KRM-II-81(5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3- yl)oxazole) and analogs selectively potentiate GABA_A receptors containing α2/3 subunits and have recently been shown to attenuate pain behaviors in several acute and chronic pain models in rodents. The present study was designed to ascertain whether KRM-II-81 and the structural analog MP-III-80 (3-ethyl-5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)-1,2,4-oxadiazole) would block chemotherapeutic agent paclitaxel-induced pain in male, C57BL/6 mice. Both compounds significantly inhibited pain behaviors evoked by cold and tactile stimulation in paclitaxel-treated mice as did the neuropathic pain drug gabapentin. Subchronic dosing for 22 days with KRM-II-81 and MP-III-80 demonstrated enduring analgesic efficacy without tolerance development, while the effects of gabapentin showed evidence of tolerance development. KRM-II-81 and MP-III-80 also decreased marble-burying behavior in this mouse strain as did the anxiolytic drug chlordiazepoxide. In contrast to KRM-II-81 and MP-III-80, chlordiazepoxide had motor-impairing effects at anxiolytic-like doses. The data add to the literature documenting that these selective potentiators of α2/3-containing GABA_A receptors are effective in a host of animal models used to detect novel analgesic drugs. The anxiolytic-like efficacy of these compounds fits well with the comorbidity of anxiety in patients with chronic pain and cancer.

Downregulation of microRNA‑29c reduces pain after child delivery by activating the oxytocin‑GABA pathway

A significant decrease in the expression of spinal microRNA-29c (miR-29c), which is responsible for the regulation of oxytocin receptor (OXTR) expression, was observed in nerve injury pain during childbirth. The present study investigates whether spinal miR-29c could be a potential target for the treatment of pain, via the oxytocin (OT)-γ-aminobutyric acid (GABA) pathway. A spared nerve injury (SNI) rat model was established to induce neuropathic pain, simulating hyperalgesia. Spinal neurons were treated with OT to mimic the hormonal changes in the central nervous system after delivery. A change in the neuronal miniature inhibitory postsynaptic currents (mIPSCs) was observed in neurons, following the silencing of miR-29c or OT treatment with or without OXTR antagonist. The Von-Frey apparatus was used to measure the animal behaviors. Molecular biological experiments and electrophysical recordings in vivo and in vitro were performed to reveal the potential analgesic mechanisms. miR-29c was significantly downregulated (more than 8-fold) in the spinal dorsal horn of delivery+SNI rats compared with the SNI rats. The silencing of miR-29c resulted in increased pain threshold in SNI rats. Bioinformatics analysis indicated that OXTR was a potential target gene of miR-29c. The delivery+SNI rats presented with higher levels of OT in the cerebrospinal fluid compared with SNI rats, which indicated that the OT signaling pathway may participate in pain relief response. The increased expression of OXTR and GABA in delivery+SNI rats were observed in the miR-29c-silenced SNI rat model, suggesting that the silencing of miR-29c can mediate pain relief by enhancing the OT-GABA pathway. In addition, an electrophysiology assay was performed to assess the mIPSCs in neurons. The silencing of miR-29c in neurons increased the frequency and amplitude of mIPSCs but there was no influence on the decay time, which suggested that the spinal inhibitory neurons became more active, subsequently reducing the feeling of pain. The inhibition of OXTR reversed the enhanced inhibitory postsynaptic currents, indicating a crucial role for OXTR in the miR-29c-associated pain regulation. Taken together, the results of the present study suggested that spinal oxytocinergic inhibitory control plays an important role in pain relief in the neuropathic pain rat model undergoing vaginal delivery. Silencing spinal miR-29c may be a potential target for pain relief through the OT-GABA pathway.

Post-operative opioid pain management patterns for patients who receive hip surgery

Background

Identifying optimal, post-operative opioid management strategies is a priority of health providers and government agencies. At present, there are no studies we are aware of that have formally investigated opioid prescribing patterns for post-operative non-arthroplasty orthopedic conditions such as femoroacetabular impingement, nor has any study investigated the influence of opioid prescription patterns on health care costs and utilization. We aimed to investigate a subgrouping scheme associated with post-operative opioid prescription strategies and measure the subgroups’ direct and indirect health care utilization and costs in individuals undergoing non-arthroplasty orthopedic hip surgery.

Methods

The study was an observational cohort of routine military clinical practices. We used cluster analysis to characterize pre-operative (12 months) and post-operative (24 months) opioid prescription patterns. Linear mixed effects modeling (with statistical controls for baseline status) identified opioid prescription pattern subgroups and identified subgroup differences in health care utilization and costs.

Results

Two distinct clusters were identified representing 1) short-duration, high total days’ supply (SD-HD), and 2) long-duration, lesser total days’ supply (LD-LD) post-operative prescription patterns. Significantly higher costs and health care utilization for both hip-related and non-hip-related variables were consistently identified in the SD-HD group.

Conclusions

Long-term opioid prescription use has been identified as a concern, but our findings demonstrate that LD-LD post-operative opioid management for hip surgery recipients was associated with lower costs and utilization. Whether these management patterns were a reflection of pre-operative health status, impacted pain-related outcomes, or can be replicated in other orthopedic procedures remains a consideration for future studies.

Trial registration

NA.

Laser acupuncture reduces pain in pediatric kidney biopsies: a randomized controlled trial

Evaluate laser acupuncture (LA) as an adjuvant therapy in pain management during percutaneous kidney biopsy procedure in children and adolescents. This prospective, double-blinded, randomized controlled trial enrolled patients aged 7 to 26 years admitted to a children's hospital for percutaneous kidney biopsy. Patients received LA to treatment points (acupuncture group) or sham points (control group) before the procedure. The laser delivered a dose of 42 J/cm over 10 acupoints. Patients and parents rated the pain during and after the biopsy, and change in pain scores were calculated for each patient. Anxiety, vital signs, sedation medication, and patient's biopsy experience were secondary outcomes. Sixty-nine treatments (33 in the acupuncture group and 36 in the control group) were eligible for analysis. Patients in the acupuncture group reported a significantly improved change in the pain score after the biopsy compared with the controls (0.8 vs -0.5, P = 0.044). Patients in the acupuncture group had a statistically significant decrease in procedure vital signs including heart rate (-1.8 vs 5.6, P = 0.043) and respiratory rate (-2.4 vs 0.4, P = 0.045) when compared with controls. Parents also perceived a correspondingly greater improvement in their child's pain for those in the acupuncture group compared with the controls (2.3 vs 0.3, P = 0.04). Adjunctive LA significantly improved pain after pediatric percutaneous kidney biopsies.

Pharmacogenetic Testing for Analgesic Adverse Effects: Pediatric Case Series

OBJECTIVES

Genetic variants in pharmacokinetic genes can alter the effectiveness and increase the risks of using analgesics to treat pain. The purpose of this retrospective study is to describe the clinical experiences that led to pharmacogenetic testing of pediatric pain management program patients for alterations in the CYP2D6, CYP2C19, and CYP2C9 genes and correlate the analgesic efficacy and adverse analgesic effects with the gene-specific findings and Metabolic Reserve (MR) index.

MATERIALS AND METHODS

Nineteen patients were referred for pharmacogenetic testing between February 2010 and December 2013 due to analgesic ineffectiveness or adverse analgesic effects. CYP2D6, CYP2C19, and CYP2C9 functional status was inferred from genotyping; and MR calculated. Data from the available inpatient and outpatient medical records from January 2007 to May 2014 for these patients were reviewed and extracted to characterize patient analgesic response phenotype.

RESULTS

Significant CYP2D6 genetic variants were identified in 16 of the 19 (84%) patients: 4 were ultra-rapid metabolizers, 8 were deficient, 3 were poor metabolizers, and 1 was CYP2D6 null metabolizer. Of the 3 patients with functional CYP2D6 status, 2 were CYP2C19 null metabolizers. The MR scores ranged from 3.0 to 7.0, with a bimodal distribution with high frequencies corresponding to 4.0/4.5 and 7.0.

DISCUSSION

Clinical evaluation of analgesic ineffectiveness and adverse effects led to the high likelihood of identifying patients with CYP2D6, CYP2C19, and CYP2C9 alleles associated with alterations in analgesic metabolism. Further research is needed to integrate pharmacogenetic and clinical information into anticipatory guidance for pharmacogenetic testing and analgesic prescribing to children with pain.

Multimodal pain management and the future of a personalized medicine approach to pain

In the soon-to-be-released clinical practice guidelines from the American Pain Society, multimodal analgesia is recommended for pain management after all surgical procedures. Multimodal analgesia is a surgery-specific population-based approach to optimize pain relief by treating pain through multiple mechanisms along multiple sites of the nociceptive pathway. The reliance on multiple medications and therapies inherent to the multimodal approach also may address individual patient differences in analgesic pharmacogenetics (ie, the influence of allelic differences in single genes and the associated variability in specific medication responses). Perioperative nurses may see a shift from surgery-specific population-based multimodal analgesic protocols to a personalized medicine approach as knowledge of the genetic influences of analgesic metabolism and pain sensitivity is translated into clinical practice. Personalized medicine is proposed as an individualized pain management treatment plan that eventually may be based on each patient's genetic coding for metabolism of analgesics and pain sensitivity.

The effect of emotional stress and depression on the prevalence of digestive diseases

Background/Aims

Epidemiological data indicate that emotional stress and depression might influence the development of gastrointestianl disorders and cancers, but the relationship between the two is still unclear. The aim was to investigate the effect of stress/depression on the prevalence of digestive diseases. In addition, we tried to identify whether stress and depression are risk factors for these diseases.

Methods

A total of 23 698 subjects who underwent a medical check-up including upper and lower endoscopy were enrolled. By review -ing the subject’s self-reporting questionnaire and endoscopic findings, we investigated the digestive diseases, including functional dyspepsia (FD), irritable bowel syndrome (IBS), reflux esophagitis, peptic ulcer disease, and adenoma and carcinoma of the stomach and colon. Stress and depression scores were measured by the Brief Encounter Psychosocial Instrument and Beck’s Depression Inventory, respectively (Korean version).

Results

Stress and depression were related to FD, IBS, and reflux esophagitis. Depression was also linked to peptic ulcer disease and adenoma/carcinoma of the colon and stomach. Multivariate analysis revealed that stress and depression were independent risk factors for FD (OR, 1.713 and 1.984; P < 0.001) and IBS (OR, 1.730 and 3.508; P < 0.001). In addition, depression was an independent risk factor for gastric adenoma/carcinoma (OR, 4.543; P < 0.001).

Conclusions

Stress and depression are related to various digestive diseases, and they may be predisposing factors for FD and IBS. Depression may also be a cause of gastric cancer. Psychological evaluation of gastroenterology patients may be necessary, but more study is needed.