Opioid-induced immunosuppression. Curr Opin Support Palliat Care. 2008;2:14-18. [PMID: 18685388 DOI: 10.1097/spc.0b013e3282f5272e]

Peripheral inflammation as a potential mechanism and preventive strategy for perioperative neurocognitive disorder under general anesthesia and surgery

General anesthesia, as a commonly used medical intervention, has been widely applied during surgical procedures to ensure rapid loss of consciousness and pain relief for patients. However, recent research suggests that general anesthesia may be associated with the occurrence of perioperative neurocognitive disorder (PND). PND is characterized by a decline in cognitive function after surgery, including impairments in attention, memory, learning, and executive functions. With the increasing trend of population aging, the burden of PND on patients and society's health and economy is becoming more evident. Currently, the clinical consensus tends to believe that peripheral inflammation is involved in the pathogenesis of PND, providing strong support for further investigating the mechanisms and prevention of PND.

Implementation of an Enhanced Recovery After Surgery Protocol for Cleft Palate Repair

OBJECTIVE

This study examines an Enhanced Recovery After Surgery (ERAS) protocol for patients with cleft palate and hypothesizes that patients who followed the protocol would have decreased hospital length of stay and decreased narcotic usage than those who did not.

DESIGN

Retrospective cohort study.

SETTING

The study takes place at a single tertiary children's hospital.

PATIENTS

All patients who underwent cleft palate repair during a 10-year period (n = 242).

INTERVENTIONS

All patients underwent cleft palate repair with the most recent cohort following a new ERAS protocol.

MAIN OUTCOME MEASURES

Primary outcomes included hospital length of stay and narcotic usage in the first 24 hours after surgery.

RESULTS

Use of local bupivacaine during surgery was associated with decreased initial 24-hour morphine equivalent usage: 2.25 vs 3.38 mg morphine equivalent (MME) (P < 0.01), and a decreased hospital length of stay: 1.71 days vs 2.27 days (P < 0.01). The highest 24-hour morphine equivalent a patient consumed prior to the ERAS protocol implementation was 24.53 MME, compared with 6.3 MME after implementation. Utilization of the ERAS protocol was found to be associated with a decreased hospital length of stay: 1.67 vs 2.18 days (P < 0.01).

CONCLUSIONS

Use of the proposed ERAS protocol may lead to lower narcotic usage and decreased length of stay.

The Association of Prescribed Opioids and Incident Cardiovascular Disease

Opioid prescribing remains common despite known overdose-related harms. Less is known about links to nonoverdose morbidity. We determined the association between prescribed opioid receipt with incident cardiovascular disease (CVD) using data from the Veterans Aging Cohort Study, a national prospective cohort of Veterans with/without Human Immunodeficiency Virus (HIV) receiving Veterans Health Administration care. Selected participants had no/minimal prior exposure to prescription opioids, no opioid use disorder, and no severe illness 1 year after the study start date (baseline period). We ascertained prescription opioid exposure over 3 years after the baseline period using outpatient pharmacy fill/refill data. Incident CVD ascertainment began at the end of the prescribed opioid exposure ascertainment period until the first incident CVD event, death, or September 30, 2015. We used adjusted Cox proportional hazards regression models with matching weights using propensity scores for opioid receipt to estimate CVD risk. Among 49,077 patients, 30% received opioids; the median age was 49 years, 97% were male, 49% were Black, and 47% were currently smoking. Prevalence of hypertension, diabetes, current smoking, alcohol and cocaine use disorder, and depression was higher in patients receiving opioids versus those not but were well-balanced by matching weights. Unadjusted CVD incidence rates per 1,000-person-years were higher among those receiving opioids versus those not: 17.4 (95% confidence interval [CI], 16.5-18.3) versus 14.7 (95% CI, 14.2-15.3). In adjusted analyses, those receiving opioids versus those not had an increased hazard of incident CVD (adjusted hazard ratio 1.16 [95% CI, 1.08-1.24]). Prescribed opioids were associated with increased CVD incidence, making opioids a potential modifiable CVD risk factor. PERSPECTIVE: In a propensity score weighted analysis of Veterans Administration data, prescribed opioids compared to no opioids were associated with an increased hazard of incident CVD. Higher opioid doses compared with lower doses were associated with increased hazard of incident CVD. Opioids are a potentially modifiable CVD risk factor.

Effect of Intraoperative Opioid Dose on Perioperative Neutrophil-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio in Glioma

Background

The neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) are inflammatory biomarkers. Until now, it is unknown the impact of opioid dosage on perioperative immunity in glioma patients. The aim of this study was to explore the effect of intraoperative opioid dosage on perioperative immune perturbations using NLR and LMR as inflammatory biomarkers and evaluate the correlation between inflammatory biomarkers and pathological grade of glioma.

Methods

The study included 208 patients with primary glioma who underwent glioma resection from February 2012 to November 2019 at Harbin Medical University Cancer Hospital. Complete blood count (CBC) was collected at 3 time points: one week before surgery, and 24 hours and one week after surgery. Patients were divided into high-dose and low-dose groups, based on the median value of intraoperative opioid dose. The relationships between perioperative NLR, LMR and intraoperative opioid dosage were analyzed using repeated measurement analysis of variance (ANOVA). Correlations between preoperative various factors and pathological grade were analyzed by Spearman analysis. Receiver operating characteristic (ROC) curves were performed to assess the predictive performance of the NLR and LMR for pathological grade.

Results

The NLR (P=0.020) and lower LMR (P=0.037) were statistically significant different between high-dose and low-dose groups one week after surgery. The area under the curve (AUC) of the NLR to identify poor diagnosis was 0.685, which was superior to the LMR (AUC: 0.607) and indicated a correlation between the NLR with pathological grade. The preoperative NLR (P=0.000), LMR (P=0.009), age (P=0.000) and tumor size (P=0.001) exhibited a significant correlation with the pathological grade of glioma.

Conclusion

Intraoperative opioids in the high-dose group were associated with higher NLR and lower LMR in postoperative glioma patients. The preoperative NLR and LMR demonstrated predictive value for distinguishing between high-grade and low-grade gliomas.

Are There Any Advantages of the Low Opioid Anaesthesia and Non-Opioid Postoperative Analgesia Protocol: A Clinical Observational Study

Purpose

The methods of perioperative analgesia and pain control have changed. The principle of opioid-based analgesia has been modified to multimodal analgesia, followed by LOA (low opioid anaesthesia) and OFA (opioid-free anaesthesia). The aim was to describe the effects of LOA on nausea, vomiting, and pain control during general anaesthesia and postoperative period after laparoscopic cholecystectomy.

Patients and Methods

The protocol included the study group-40 patients received low-opioid anaesthesia (LOA), and the control group-40 patients received general anaesthesia with opioid analgesia (OA). The scheme of LOA was based on ketamine, lidocaine, magnesium sulfate, paracetamol, and metamizole. The OA was based on standard opioid (fentanyl) administration in induction and maintenance phase due to clinical observation. Postoperative analgesia included 1g of paracetamol and 1g of metamizol intravenously, with a 6-hour interval between doses.

Results

Significant differences in the pain score in the periods of 2-6, 6-12, and 12-24 hours after anaesthesia between the groups were noticed (p < 0.001). Moreover, a significant difference in the frequency of nausea (p = 0.005) and vomiting (p = 0.04) between groups were presented. Nausea occurred in 54.05% of OA group, while in the LOA group, it occurred in a 23.08%. Vomiting occurred in 32.43% of control group, while in the study group, it occurred in 12.82% of patients.

Conclusion

The LOA protocol was more beneficial in reducing nausea and vomiting than the opioid-based method of anaesthesia. The LOA protocol of general anaesthesia during laparoscopic cholecystectomy and non-opioid postoperative analgesia have better outcomes in pain control, as well as nausea and vomiting, and improve postoperative patient comfort. The LOA protocol during anaesthesia and non-opioid postoperative analgesia should be considered in routine practice.

TEDOFA Trial Study Protocol: A Prospective Double-Blind, Randomized, Controlled Clinical Trial Comparing Opioid-Free versus Opioid Anesthesia on the Quality of Postoperative Recovery and Chronic Pain in Patients Receiving Thoracoscopic Surgery

Introduction

Seeking effective multimodal analgesia and anesthetic regimen is the basis for the success of ERAS. Opioid-free anesthesia (OFA) is a multimodal anesthesia associating hypnotics, N-methyl-D-aspartate (NMDA) antagonists, local anesthetics, anti-inflammatory drugs and α-2 agonists. Although previous studies have confirmed that OFA is safe and feasible for VATS surgery, there is great heterogeneity in how to select and combine anti-harm drugs to replace opioids. We hypothesized that the reduced opioid use during and after surgery allowed by OFA compared with standard of care will be associated with a reduction of postoperative opioid-related adverse events and an improvement in the quality of rehabilitation of patients after partial VATS lung resection.

Methods/Analysis

The TEDOFA Study is a prospective double-blind, randomized, controlled clinical trial with a concealed allocation of patients scheduled to undergo elective partial VATS pneumonectomy 1:1 to receive either a standard anesthesia protocol or an OFA. A total of 146 patients were recruited in the study. Primary endpoint was the 15-item recovery quality scale (QoR-15) at 24 hours after surgery.

Ethics and Dissemination

This trial has been approved by the Institutional Review Board of Beijing Friendship Hospital of China Capital University. The TEDOFA trial study protocol was approved on 27 February 2023. The trial started recruiting patients after registered on the Chinese Clinical Trial Registry.

Trial Registration Number

ChiCTR2300069210; Pre-results.

The Effect of Prenatal and Neonatal Fluoride Exposure to Morphine-Induced Neuroinflammation

Physical dependence is associated with the formation of neuroadaptive changes in the central nervous system (CNS), both at the molecular and cellular levels. Various studies have demonstrated the immunomodulatory and proinflammatory properties of morphine. The resulting neuroinflammation in drug dependence exacerbates substance abuse-related behaviors and increases morphine tolerance. Studies prove that fluoride exposure may also contribute to the development of neuroinflammation and neurodegenerative changes. Morphine addiction is a major social problem. Neuroinflammation increases tolerance to morphine, and neurodegenerative effects caused by fluoride in structures related to the development of dependence may impair the functioning of neuronal pathways, change the concentration of neurotransmitters, and cause memory and learning disorders, which implies this element influences the development of dependence. Therefore, our study aimed to evaluate the inflammatory state of selected brain structures in morphine-dependent rats pre-exposed to fluoride, including changes in cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) expression as well as microglial and astroglial activity via the evaluation of Iba1 and GFAP expression. We provide evidence that both morphine administration and fluoride exposure have an impact on the inflammatory response by altering the expression of COX-1, COX-2, ionized calcium-binding adapter molecule (Iba1), and glial fibrillary acidic protein (GFAP) in brain structures involved in dependence development, such as the prefrontal cortex, striatum, hippocampus, and cerebellum. We observed that the expression of COX-1 and COX-2 in morphine-dependent rats is influenced by prior fluoride exposure, and these changes vary depending on the specific brain region. Additionally, we observed active astrogliosis, as indicated by increased GFAP expression, in all brain structures of morphine-dependent rats, regardless of fluoride exposure. Furthermore, the effect of morphine on Iba1 expression varied across different brain regions, and fluoride pre-exposure may influence microglial activation. However, it remains unclear whether these changes are a result of the direct or indirect actions of morphine and fluoride on the factors analyzed.

Opioid Therapy and Implications for Oxidative Balance: A Clinical Study of Total Oxidative Capacity (TOC) and Total Antioxidative Capacity (TAC)

BACKGROUND

Opioids are used in pharmacotherapy for chronic pain. The phenomenon of their influence on the oxidative-antioxidant balance is poorly understood. Additionally, little is known about the oxidative status in patients receiving chronic opioid noncancer pain therapy.

METHODS

The primary goal was to explore oxidative status using the total oxidative capacity (TOC) and total antioxidative capacity (TAC) in patients with chronic lower back pain (LBP) treated with opioids. The secondary task was to present the risk factors connected with the duration of therapy or anthropometric parameters. Plasma TOC and TAC were analyzed in the study group (n = 28), i.e., patients with chronic LBP treated with opioids, and in the control group (n = 11), i.e., healthy volunteers.

RESULTS

The TAC was significantly lower in the study group compared to the control group (p < 0.05), while the TOC did not differ significantly. A statistically lower TOC for buprenorphine compared to oxycodone (p = 0.019) and tramadol (p = 0.036) was observed. The TOC did not differ between tramadol and oxycodone. The highest TAC was described for oxycodone, while the TAC for buprenorphine and tramadol was significantly lower in comparison with oxycodone (p = 0.007 and p = 0.016). The TOC/TAC ratio was higher in patients with nicotinism in both groups.

CONCLUSIONS

Patients receiving chronic opioid therapy presented a lower antioxidative capacity. There were differences in opioid-induced oxidative imbalance, which is very important clinically. Nicotinism increases the oxidative-antioxidative imbalance. The least oxidative capacity was associated with buprenorphine, while oxycodone showed the greatest antioxidant activity. The most favorable TOC/TAC ratio was observed for buprenorphine. It is suggested that buprenorphine or oxycodone has the best profile, and there is no correlation with the duration of opioid therapy or the opioid dose. However, all opioid substances can potentially enhance the oxidative-antioxidative status.

The toll of opioid dependence: A research report on the possible role of Toll-like receptor-4 and related immune markers in opioid dependence

Background

The opioid receptors in the central nervous system and immune system contribute to its reinforcing effect. Xenobiotics-associated molecular pattern of opioids interacts with Toll-like receptor-4 (TLR-4) on the glial cell surface and increases dopaminergic activity in the nucleus accumbens in preclinical studies. We wanted to examine whether treatment with buprenorphine-naloxone (BNX) might be associated with changes in immunological markers in individuals with opioid dependence (OD).

Methods

We recruited 30 individuals with OD on buprenorphine and 30 age- and sex-matched healthy controls (HCs). We measured the neutrophil (N), lymphocyte (L), CD-4, and CD-8 T-cell count and estimated plasma TLR-4 level in the HC group once. We measured the immunological markers, craving, pain, and perceived stress in the OD group at the treatment initiation (baseline) and after 4 weeks (±2 weeks) of treatment with BNX.

Results

The mean severity score on the OD questionnaire was 72.8 (SD 5.4). At baseline, OD had a higher N: L ratio and lower lymphocyte percentage than HC. Plasma TLR-4 concentration increased significantly after 1 month of treatment (t = -3.09, P = 0.004). Craving, pain, and perceived stress correlated with absolute neutrophil count, N: L ratio, and CD-8 T-cell count, although lost significance after corrections for multiple comparisons.

Conclusion

The increase in TLR-4 after treatment with BNX may indicate the rescue from nonprescription opioid-induced immunosuppression or the introduction of a novel xenobiotics-associated molecular pattern of BNX.

Does Preoperative Opiate Choice Increase Risk of Postoperative Infection and Subsequent Surgery?

BACKGROUND

Opioids are commonly prescribed for chronic pain before spinal surgery and research has shown an increased rate of postoperative adverse events in these patients.

OBJECTIVE

This study compared the incidence of 2-year subsequent surgical procedures and postoperative adverse events in patients undergoing lumbar fusion with or without 90-day preoperative opioid use. We hypothesized that patients using preoperative opioids would have a higher incidence of subsequent surgery and adverse outcomes.

METHODS

A retrospective cohort study was performed using the Optum Pan-Therapeutic Electronic Health Records database including adult patients who had their first lumbar fusion between 2015 and 2018. The daily average preoperative opioid dosage 90 days before fusion was determined as morphine equivalent dose and further categorized into high dose (morphine equivalent dose >100 mg/day) and low dose (1-100 mg/day). Clinical outcomes were compared after adjusting for confounders.

RESULTS

A total of 23,275 patients were included, with 2112 patients (10%) using opioids preoperatively. There was a significantly higher incidence of infection compared with nonusers (12.3% vs. 10.1%; P = 0.01). There was no association between subsequent fusion surgery (7.9% vs. 7.5%; P = 0.52) and subsequent decompression surgery (4.1% vs. 3.6%; P = 0.3) between opioid users and nonusers. Regarding postoperative infection risk, low-dose users showed significantly higher incidence (12.7% vs. 10.1%; P < 0.01), but high-dose users did not show higher incidence than nonusers (7.5% vs. 10.1%; P = 0.23).

CONCLUSIONS

Consistent with previous studies, opioid use was significantly associated with a higher incidence of 2-year postoperative infection compared with nonuse. Low-dose opioid users had higher postoperative infection rates than did nonusers.

Management of Pelvic Pain in Patients with Crohn's Disease-Current Overview

Crohn's disease (CD) is a subtype of chronic inflammatory bowel diseases (IBD) with characteristic skip lesions and transmural inflammation that may affect the entire gastrointestinal tract from the mouth to the anus. Persistent pain is one of the main symptoms of CD. This pain has multifactorial pathogenesis, but most often arises from intestinal inflammation itself, as well as from gut distention or partial intestinal obstruction. Some current evidence also suggests sensitization of sensory pathways, as well as modulation of those signals by the central nervous system, which highlights the impact of biopsychosocial factors. To date, most studies have focused only on the pain located in the abdomen, while pelvic pain has rarely been explored, despite it being a common symptom. The aim of this study is to provide an abbreviated summary of the current state of knowledge on the origins and treatment of pelvic pain in CD.

Top Ten Tips Palliative Care Clinicians Should Know About Buprenorphine

Pain management in palliative care (PC) is becoming more complex as patients survive longer with life-limiting illnesses and population-wide trends involving opioid misuse become more common in serious illness. Buprenorphine, a generally safe partial mu-opioid receptor agonist, has been shown to be effective for both pain management and opioid use disorder. It is critical that PC clinicians become comfortable with indications for its use, strategies for initiation while understanding risks and benefits. This article, written by a team of PC and addiction-trained specialists, including physicians, nurse practitioners, social workers, and a pharmacist, offers 10 tips to demystify buprenorphine use in serious illness.

Association between long-term opioid use and cancer risk in patients with chronic pain: a propensity score-matched cohort study

BACKGROUND

Whether long-term opioid use is an independent risk factor for cancer progression remains unclear. Therefore, we conducted a propensity score-matched population-based cohort study to compare cancer incidence between patients with chronic pain with and without opioid use.

METHODS

Data from January 2008 to December 2019 were obtained from the Taiwan National Health Insurance Research Database. Patients were categorised into two groups according to the presence or absence of opioid use, and matched at a 4:1 ratio. The incidence rate ratios for specific cancers were determined.

RESULTS

Propensity score-matching yielded 63 610 patients: 50 888 with opioid use (the opioid group) and 12 722 without (the non-opioid group). In a multivariate Cox regression analysis, the adjusted hazard ratio (95% confidence interval) for cancers in the opioid group compared with the non-opioid group was 2.66 (1.44-2.94; P<0.001). The incidence rate ratios (95% confidence interval) for lung, hepatocellular, colorectal, breast, prostate, head and neck, pancreatic, gastric, oesophageal, and ovarian cancers for the opioid group were 1.87 (1.41-2.43), 1.97 (1.56-2.50), 2.39 (1.87-3.03), 2.43 (1.75-3.33), 2.00 (1.35-3.03), 1.79 (1.14-2.86), 1.87 (1.13-2.12), 2.43 (1.52-3.85), 1.82 (0.92-3.70), and 2.33 (1.01-5.55), respectively.

CONCLUSION

There was an association between long-term opioid use and development of cancer in patients with chronic pain, which should be confirmed in future studies.

Preoperative Opioid Dose and Surgical Outcomes in Colorectal Surgery

BACKGROUND

The worsening opioid epidemic has led to an increased number of surgical patients with chronic preoperative opioid use. However, the impact of opioids on perioperative outcomes has yet to be fully elucidated. The purpose of this study was to assess the association between preoperative opioid dose and surgical outcomes among colectomy patients.

METHODS

Adult colectomy patients in the IBM MarketScan database (2010-2017) were stratified based on preoperative opioid dose, calculated as the average opioid dose in morphine milligram equivalents (MME) in the 90 days prior to surgery: 0 MME, 1 to 49 MME, and 50 or more MME. The association between preoperative opioid dose and anastomotic leak, the primary outcome of interest, as well as other postoperative complications, was assessed using multivariable regression.

RESULTS

Among 45,515 adult colectomy patients, 71.4% did not use opioids (0 MME), 27.4% had an opioid dose between 1 and 49 MME, and 1.2% had an opioid dose at or above 50 MME. Patients with preoperative opioid use exhibited a higher incidence of anastomotic leak (0 MME: 4.8%, 1-49 MME: 5.5%, ≥50 MME: 8.3%; p trend = 0.001). Multivariable analysis demonstrated a dose-response relationship between preoperative opioids and surgical outcomes, as the odds of anastomotic leak worsened with increasing opioid dose (1-49 MME: OR 1.19, 95% CI 1.08-1.31, p < 0.001; ≥50 MME: OR 1.64, 95% CI 1.20-2.24, p = 0.002). Similar dose-response relationships were seen after risk-adjustment for lung complications, pneumonia, delirium, and 30-day readmission (p < 0.05 for all).

CONCLUSIONS

Providers should exercise caution when prescribing opioids preoperatively, as increasing doses of preoperative opioids were associated with worse surgical outcomes and higher 30-day readmission among adult colectomy patients.

Less Well-Known Consequences of the Long-Term Use of Opioid Analgesics: A Comprehensive Literature Review

BACKGROUND

The adverse effects of short-term opioid analgesics are well known and acknowledged; however, the spectrum of the sequelae of long-term use seems less clear. Some effects may remain undetected but still have the potential to cause harm and reduce patients' quality of life.

OBJECTIVE

To review the literature on the adverse effects of long-term opioid therapy.

METHODS

We performed a quasi-systematic search, analyzing articles published in the MEDLINE database between January 2000 and March 2021 that identified adverse effects of opioids used for chronic pain treatment.

RESULTS

Growing evidence indicates that there are multiple serious adverse effects of opioid treatment. Long-term opioid use may have significant effects on the endocrine, immune, cardiovascular, respiratory, gastrointestinal, and neural systems. Studies show that long-term opioid treatment increases the risk of fractures, infections, cardiovascular complications, sleep-disordered breathing, bowel dysfunction, overdose, and mortality. Opioids may potentially affect cancer development. Most consequences of the long-term use of opioids have been identified in studies of patients with non-malignant pain.

CONCLUSION

Studies indicate that long-term use of opioids increases the risk of drug-related events in a significant number of patients. Clinicians should be aware of these complications associated with prescribing opioids, discuss them with patients, prevent complications, if possible, and diagnose them early and manage adequately. More human studies are needed to assess the risk, including trials with individual opioids, because they have different adverse effect profiles.

Intensity of perioperative analgesia but not pre-treatment pain is predictive of survival in dogs undergoing amputation plus chemotherapy for extremity osteosarcoma

The purpose of this bi‐institutional retrospective study was to determine whether, in dogs treated with limb amputation and adjunctive chemotherapy for osteosarcoma, oncologic outcomes are impacted by either: (1) baseline cancer pain severity, or (2) the approaches used for perioperative pain management. Data were extracted from the medical records of 284 dogs that underwent both limb amputation and chemotherapy (carboplatin and/or doxorubicin) between 1997 and 2017 for localized (non‐metastatic) osteosarcoma of the appendicular skeleton. Kaplan–Meier survival curves and Cox proportional hazard (PH) models were used to determine the impact that retrospectively scored baseline pain levels (high vs. low) and various analgesic and local anaesthetic treatments had on both metastasis‐free survival and all‐cause mortality. For the entire population, the median disease free interval and median overall survival times were 253 and 284 days, respectively. Baseline pain was rated as “low” in 84 dogs, and “high” in 190 dogs; pain severity had no detectable effect on either metastasis‐free survival or all‐cause mortality. When accounting for the potential influences of known prognostic factors, dogs treated with what was characterized as a high‐intensity perioperative analgesic plan (including both a non‐steroidal anti‐inflammatory drug [NSAID] and a bupivacaine‐eluting soaker catheter placed at the amputation site) had a higher probability of survival than dogs treated with a low‐intensity perioperative analgesic plan (neither an NSAID, nor a soaker catheter); the median overall survival times were 252 and 378 days, respectively (hazard ratio: 2.922; p = .020).

Effects of the peripherally acting μ-opioid receptor antagonist methylnaltrexone on acute pancreatitis severity: study protocol for a multicentre double-blind randomised placebo-controlled interventional trial, the PAMORA-AP trial

Background

Moderate to severe acute pancreatitis (AP) is associated with a high rate of complications and increased mortality, yet no targeted pharmacologic treatment currently exists. As pain is a dominant symptom in AP, patients are exposed to excess levels of both endo- and exogenous opioids, which may have harmful effects on the course of AP. This trial investigates the effects of the peripherally acting μ-opioid receptor antagonist (PAMORA) methylnaltrexone on disease severity and clinical outcomes in patients with moderate to severe AP.

Methods

PAMORA-AP is a multicentre, investigator-initiated, double-blind, randomised, placebo-controlled, interventional trial, which will be conducted at four referral centres for acute pancreatitis in Denmark. Ninety patients with early-onset AP (pain onset within 48 h) as well as predicted moderate to severe disease (two or more systemic inflammatory response syndrome criteria upon admission) will be prospectively included. Subsequently, participants will be randomised (1:1) to intravenous treatment with either methylnaltrexone or matching placebo (Ringer’s lactate) during 5 days of admission. The primary endpoint will be the group difference in disease severity as defined and measured by the Pancreatitis Activity Scoring System (PASS) score 48 h after randomisation. Secondary endpoints include daily PASS scores; disease severity according to the Atlanta classification; quantification of need for analgesics, nutritional support, intravenous fluid resuscitation and antibiotics; duration of hospital admissions, readmission rates and mortality. Pain intensity and gut function will be self-reported using validated questionnaires. Exploratory endpoints include circulating levels of pro-and anti-inflammatory markers, polyethylene glycol recovery from the urine, circulating levels of blood markers of intestinal permeability, the prevalence of pancreatic complications on computed tomography (CT) scans, and colon transit time assessed using a CT-based radiopaque marker method.

Discussion

This trial aims to evaluate the PAMORA methylnaltrexone as a novel targeted pharmacotherapy in patients with moderate to severe AP with the potential benefit of improved patient outcomes.

Trial registration

ClinicalTrials.govNCT04743570. Registered on 28 January 2021. EudraCT 2020-002313-18.

Epidemiology, Outcomes, and Trends of Patients With Sepsis and Opioid-Related Hospitalizations in U.S. Hospitals

OBJECTIVES

Widespread use and misuse of prescription and illicit opioids have exposed millions to health risks including serious infectious complications. Little is known, however, about the association between opioid use and sepsis.

DESIGN

Retrospective cohort study.

SETTING

About 373 U.S. hospitals.

PATIENTS

Adults hospitalized between January 2009 and September 2015.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Sepsis was identified by clinical indicators of concurrent infection and organ dysfunction. Opioid-related hospitalizations were identified by the International Classification of Diseases, 9th Revision, Clinical Modification codes and/or inpatient orders for buprenorphine. Clinical characteristics and outcomes were compared by sepsis and opioid-related hospitalization status. The association between opioid-related hospitalization and all-cause, in-hospital mortality in patients with sepsis was assessed using mixed-effects logistic models to adjust for baseline characteristics and severity of illness.The cohort included 6,715,286 hospitalizations; 375,479 (5.6%) had sepsis, 130,399 (1.9%) had opioid-related hospitalizations, and 8,764 (0.1%) had both. Compared with sepsis patients without opioid-related hospitalizations (n = 366,715), sepsis patients with opioid-related hospitalizations (n = 8,764) were younger (mean 52.3 vs 66.9 yr) and healthier (mean Elixhauser score 5.4 vs 10.5), had more bloodstream infections from Gram-positive and fungal pathogens (68.9% vs 47.0% and 10.6% vs 6.4%, respectively), and had lower in-hospital mortality rates (10.6% vs 16.2%; adjusted odds ratio, 0.73; 95% CI, 0.60-0.79; p < 0.001 for all comparisons). Of 1,803 patients with opioid-related hospitalizations who died in-hospital, 928 (51.5%) had sepsis. Opioid-related hospitalizations accounted for 1.5% of all sepsis-associated deaths, including 5.7% of sepsis deaths among patients less than 50 years old. From 2009 to 2015, the proportion of sepsis hospitalizations that were opioid-related increased by 77% (95% CI, 40.7-123.5%).

CONCLUSIONS

Sepsis is an important cause of morbidity and mortality in patients with opioid-related hospitalizations, and opioid-related hospitalizations contribute disproportionately to sepsis-associated deaths among younger patients. In addition to ongoing efforts to combat the opioid crisis, public health agencies should focus on raising awareness about sepsis among patients who use opioids and their providers.

Opiates Possibly Boosted Human Civilization

: Testosterone is a fundamental biological drive for human survival. Evidence documents an association between the evolutionary suppression of testosterone and the civilization processes, especially their socialization and family colonization abilities, among early humans. Interestingly, opiates suppress testosterone as a side effect. However, in clinical practice, clients undergoing opioid substitution therapy have subnormal, normal, or even above-normal testosterone. This paper discusses a possibility indicating that opiates promoted civilization processes among early humans. We further suggest that modern humans might have inherited the positive impact of opiates on early humans as a biological propensity for using opioids. Some users may use opioids for self-medication to decrease their extraordinarily high testosterone levels.

Transdermal buprenorphine for pain management in children

Pain is one of the main symptoms reported by sick children, particularly by those suffering from cancer. Opioids are very useful in controlling this symptom but they are burdened with significant side effects that limit their use in children. Buprenorphine is a strong opioid that, due to its particular pharmacological characteristics, ensures excellent pain relief with fewer side effects than other opioids. The transdermal formulation allows for good pain control associated with optimal compliance by patients and few limitations on daily life. Unfortunately, transdermal buprenorphine use remains off-label for the control of chronic pain in children; therefore, it is desirable that new studies can validate its use in the paediatric population. This review aims to analyse the clinical advantages of transdermal buprenorphine in the paediatric population and the possible side effects registered in daily clinical practice.

Buprenorphine Increases HIV-1 Infection In Vitro but Does Not Reactivate HIV-1 from Latency

BACKGROUND

medication-assisted treatment (MAT) with buprenorphine is now widely prescribed to treat addiction to heroin and other illicit opioids. There is some evidence that illicit opioids enhance HIV-1 replication and accelerate AIDS pathogenesis, but the effect of buprenorphine is unknown.

METHODS

we obtained peripheral blood mononuclear cells (PBMCs) from healthy volunteers and cultured them in the presence of morphine, buprenorphine, or methadone. We infected the cells with a replication-competent CCR5-tropic HIV-1 reporter virus encoding a secreted nanoluciferase gene, and measured infection by luciferase activity in the supernatants over time. We also surveyed opioid receptor expression in PBMC, genital epithelial cells and other leukocytes by qPCR and western blotting. Reactivation from latency was assessed in J-Lat 11.1 and U1 cell lines.

RESULTS

we did not detect expression of classical opioid receptors in leukocytes, but did find nociception/orphanin FQ receptor (NOP) expression in blood and vaginal lymphocytes as well as genital epithelial cells. In PBMCs, we found that at physiological doses, morphine, and methadone had a variable or no effect on HIV infection, but buprenorphine treatment significantly increased HIV-1 infectivity (median: 8.797-fold increase with 20 nM buprenorphine, eight experiments, range: 3.570-691.9, p = 0.0078). Using latently infected cell lines, we did not detect reactivation of latent HIV following treatment with any of the opioid drugs.

CONCLUSIONS

our results suggest that buprenorphine, in contrast to morphine or methadone, increases the in vitro susceptibility of leukocytes to HIV-1 infection but has no effect on in vitro HIV reactivation. These findings contribute to our understanding how opioids, including those used for MAT, affect HIV infection and reactivation, and can help to inform the choice of MAT for people living with HIV or who are at risk of HIV infection.

Association between preoperative administration of gabapentinoids and 30-day hospital readmission: A retrospective hospital registry study

STUDY OBJECTIVE

To evaluate the effectiveness of preoperative gabapentinoid administration.

DESIGN

Retrospective hospital registry study.

SETTING

Tertiary referral center (Boston, MA).

PATIENTS

111,008 adult non-emergency, non-cardiac surgical patients between 2014 and 2018.

INTERVENTIONS

Preoperative administration of gabapentinoids (gabapentin or pregabalin).

MEASUREMENTS

We tested the primary hypothesis that preoperative gabapentinoid use was associated with lower odds of hospital readmission within 30 days. Contingent on this hypothesis, we examined whether lower intraoperative opioid utilization mediated this effect. Secondary outcome was postoperative respiratory complications.

MAIN RESULTS

Gabapentinoid administration was associated with lower odds of readmission (adjusted odds ratio [OR_adj] 0.80 [95% CI, 0.75-0.85]; p < 0.001). This effect was in part mediated by lower intraoperative opioid utilization in patients receiving gabapentinoids (8.2% [2.4-11.5%]; p = 0.012). Readmissions for gastrointestinal disorders (OR_adj 0.74 [0.60-0.90]; p = 0.003), neuro-psychiatric complications (OR_adj 0.66 [0.49-0.87]; p = 0.004), non-surgical site infections (OR_adj 0.68 [0.52-0.88; p = 0.004) and trauma or poisoning (OR_adj 0.25 [0.16-0.41]; p < 0.001) occurred less frequently in patients receiving gabapentinoids. The risk of postoperative respiratory complications was lower in patients receiving gabapentinoids (OR_adj 0.77 [0.70-0.85]; p < 0.001). Lower doses of pregabalin (< 75 mg) and gabapentin (< 300 mg) compared to both, no and high-dose administration of gabapentinoids, were associated with a lower risk of postoperative respiratory complications (OR_adj 0.61 [0.50-0.75]; p < 0.001 and OR_adj 0.70 [0.53-0.92]; p = 0.012, respectively). These lower gabapentinoid doses prevented 30-day readmission (OR_adj 0.74 [0.65-0.85]; p < 0.001). The results were robust in several sensitivity analyses including surgical procedure defined subgroups and patients undergoing ambulatory surgery.

CONCLUSIONS

The preoperative use of pregabalin and gabapentin, up to doses of 75 and 300 mg respectively, mitigates the risks of hospital readmission and postoperative respiratory complications which can in part be explained by lower intraoperative opioid use. Further research is warranted to elucidate mechanisms of the preventive action.

Anesthesia Medications and Interaction with Chemotherapeutic Agents

Cancer is now a leading health concern worldwide. In an effort to provide these patients with adequate care, coordination between anesthesiologists and surgeons is crucial. In cancer-related treatment, it is very clear that radio-chemotherapy and medical procedures are important. There are some obstacles to anesthesia when dealing with cancer treatment, such as physiological disturbances, tumor-related symptoms, and toxicity in traditional chemotherapy treatment. Therefore, it is important that a multisystemic, multidisciplinary and patient-centered approach is used to preserve perioperative homeostasis and immune function integrity. Adding adjuvants can help increase patient safety and satisfaction and improve clinical efficacy. Correctly paired anesthetic procedures and medications will reduce perioperative inflammatory and immune changes that could potentially contribute to improved results for future cancer patients. Further research into best practice strategies is required which will help to enhance the acute and long-term effects of cancer care in clinical practice.

Opioid Use and Chronic Infections: The Value of Addressing the Syndemic in Correctional Settings Via Telemedicine Guidance and Broader Use of Long-Acting Medications

In the United States, we are experiencing linked epidemics (a syndemic) of substance use disorders (SUDs) and infections associated with drug use, including unsafe injecting and unsafe sex in exchange for drugs or money. Current drug laws, together with risk-taking behavior among persons with SUDs, contribute to disproportionately high prevalences of these conditions in correctional settings. Detection and treatment of diseases with a high impact on public health are best addressed in the settings where such conditions are most prevalent (ie, jails and prisons for SUDs and chronic infections). The effectiveness, safety, cost of care. and public health impact of these conditions can be improved by means of broader screening and expanded access to specialty consultations through telemedicine/telehealth, along with broader use of long-acting medications for the treatment of human immunodeficiency virus and SUDs. Expanding telemedicine/telehealth, first for specialties which do not require advanced technology (eg, infectious diseases, addictions), can eventually lead to further advancements in correctional healthcare.

The Reasons for Higher Mortality Rate in Opium Addicted Patients with COVID-19: A Narrative Review

The outbreak of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) caused COVID-19 has developed into an unexampled worldwide pandemic. The most important cause of death in patients with COVID-19 is Acute Respiratory Distress Syndrome (ARDS). Opium is widely used for its analgesic features in control of acute and chronic pain related to different diseases. Opium consumption is increased over the last three decades and leads to adverse effects on the respiratory system; opium also affects the lungs' functions and respiration. The contemplative issue is the higher mortality rate due to SARS-CoV-2 infection in opium addicts' patients. Studies have shown that despite the decrease in proinflammatory cytokines production in opium addicts, there are at least 4 reasons for this increase in mortality rate: downregulation of IFNs expression, development of pulmonary edema, increase thrombotic factors, increase the expression of Angiotensin-converting enzyme 2 (ACE2). Therefore, identifying the causes of mortality and approved therapies for the treatment of COVID-19 patients who use opium for any reason is an important unmet need to reduce SARS-CoV-2 infection-related mortality. This review study demonstrated the effects of opium on immune responses and the reasons for the higher mortality rate in opium addicts' patients with COVID-19.

Meta-analysis of retrospective studies suggests that the pre-operative opioid use is associated with an increased risk of adverse outcomes in total hip and or knee arthroplasty

BACKGROUND

Opioid use is prevalent in the general population. This systematic review and meta-analysis sought to evaluate whether it affects patient-reported outcomes (PROs) following total hip or knee arthroplasty.

METHODS

The following databases were systematically searched on February 5, 2020: Medline, Embase (Ovid), Cochrane Library, and Web of Science. Studies were included if they compared patients who received opioids or not before total hip or knee arthroplasty. Outcomes of interest were rates of post-operative revision, peri-prosthetic infection, and readmission.

RESULTS

Ten retrospective studies were included for review. Pre-operative opioid use was identified as a risk factor for post-operative revision [odds ratio (OR) 1.58, 95% confidence interval (CI) 1.15-1.73, p<0.01], peri-prosthetic infection (OR 1.36, 95% CI 1.08-1.71, p=0.01), and readmission (OR 1.41, 95% CI 1.20-1.75, p<0.01).

CONCLUSION

The available evidence indicates that pre-operative opioid use increases the risk of adverse outcomes following total hip or knee arthroplasty. Orthopedic physicians should consider these risks when treating their patients.

Opioid use prior to admission for chemotherapy induced febrile neutropenia is associated with increased documented infection, sepsis, and death

PURPOSE

Cancer patients on chemotherapy are at risk for developing febrile neutropenia and infections. Opioids have been associated with immune suppression and risk of infection. We aimed to investigate opioid use associated with infections and death among cancer patients admitted with febrile neutropenia.

METHODS

A total of 481 patients admitted for chemotherapy-induced febrile neutropenia were reviewed. There were 274 patients with opioid prescriptions (OP) within 10 days of hospitalization and 207 patients without opioid prescriptions (NOP) for >1 year of hospitalization. The primary outcomes were microbiologically and clinically documented infection as defined by the International Immunocompromised Host Society (IHS), sepsis by clinician, systemic inflammatory response syndrome (SIRS) criteria, and sequential organ failure assessment (SOFA) score.

RESULTS

Documented infection occurred in 192 (70%) of patients with opioids compared to 99 (48%) with non-opioids, p < 0.001. Similar results were observed in sepsis by SOFA score with 173 (63%) opioids versus 92 (44%) non-opioids, p < 0.001, and sepsis by SIRS with 225 (82%) and 115 (56%) respectively, p < 0.001. Multivariable analysis showed opioid use has an increased adjusted odds of documented infection by 7.13 fold (95% CI 3.97-12.78), Sepsis by SOFA by 2.39 fold (95% CI 1.33-4.29), and Sepsis by SIRS by 1.87 fold (95% CI 1.13-3.10). Multivariable analysis for death/hospice showed that opioids had 2.30 fold (95% CI 1.16-4.57) increase in adjusted odds of death/hospice within 30 days of discharge.

CONCLUSION

The data supports that patients with prior opioid use is associated with increased odds for infection, sepsis and death than non-opioid users admitted with febrile neutropenia.

Effect of Dexmedetomidine on Perioperative Stress Response and Immune Function in Patients With Tumors

Objective:

This study aims to investigate the effect of dexmedetomidine on perioperative stress response and immune function in patients with tumors.

Methods:

Sixty patients who underwent selective radical gastrectomy for cancer were randomly divided into 3 groups: remifentanil group (group R), dexmedetomidine group (group D), and sufentanil group (group S). Remifentanil, dexmedetomidine, and sufentanil were used as general anesthetics. Endotracheal intubation and mechanical ventilation were performed after the spontaneous respiration disappeared. Then, the data were recorded, and blood samples were collected at all time points.

Results:

The heart rate significantly increased (P < 0.05) at T1 in group S, and both heart rate and mean arterial pressure significantly increased (P < 0.05) in group R when compared to group D. The heart rate significantly increased (P < 0.05) at T2 in group S and group R. Furthermore, the heart rate significantly increased (P < 0.05) at T3 and T4 in group S and group R. Intra-group comparison: The heart rate at T1–T4 and mean arterial pressure at T1–T4 significantly increased (P < 0.05) in group S, and the heart rate at T1 and T4, and mean arterial pressure at T2–T4 significantly increased (P < 0.05) in group R when compared to T0. The serum IL-6, IFN-γ, and β-EP significantly increased (P < 0.05) at T0’ in group S and group R when compared to group D. Blood glucose, and serum IL-10, IFN-γ, and β-EP significantly increased (P < 0.05), while IL-18 significantly decreased (P < 0.05) at T1’ in group S and group R.

Conclusion:

Continuous infusion of dexmedetomidine in combination with the inhalation of sevoflurane is superior to sevoflurane + remifentanil or sufentanil in patients undergoing tumor surgery.

One-Year Results of Prospective Research Study Using 10 kHz Spinal Cord Stimulation in Persistent Nonoperated Low Back Pain of Neuropathic Origin: Maiden Back Study

PURPOSE

Spinal cord stimulation (SCS) is a recommended treatment for chronic neuropathic pain. Persistent nonoperative low back pain of neuropathic origin has profound negative impacts on patient's lives. This prospective, open label, research study aimed to explore the use of SCS in patients with associated features of central sensitisation such as allodynia and hyperalgesia.

MATERIALS AND METHODS

Twenty-one patients with back pain and hyperalgesia or allodynia who had not had prior spinal surgery underwent a SCS trial followed by full implantation. SCS comprised administering electrical impulses epidurally at a frequency of 10 kHz and pulse width of 30 μsec. Patients attended follow-up visits after 6 and 12 months of SCS. Repeated measure ANOVAs/Friedman tests explored change after 6 and 12 months of 10 kHz SCS. Independent sample t-tests/Mann-Whitney U tests examined differences in response after 12 months of 10 kHz SCS.

RESULTS

Back and leg pain, quality of life (QoL), pain-related disability, and morphine equivalence significantly improved compared with baseline following 6 and 12 months of 10 kHz SCS. There were no increases in the consumption of opioids, amitriptyline, gabapentin or pregabalin in any patient. After 12 months of treatment, 52% encountered ≥50% improvement in back pain, 44% achieved remission (0-3 cm back pain VAS), 40% reported ODI scores between 0 and 40 and 60% experienced a reduction of at least 10 ODI points. Patients reporting ≥10-point improvement in ODI had significantly longer pain history durations and experienced significantly greater improvements in back pain, leg pain and QoL than those reporting <10-point improvement in ODI.

CONCLUSION

The 10 kHz SCS improved back and leg pain, QoL, pain-related disability and medication consumption in patients with nonoperative back pain of neuropathic origin. With further research incorporating a sham control arm, the efficacy of 10 kHz SCS in this patient cohort will become more established.

A double-edged sword of using opioids and COVID-19: a toxicological view

Today, COVID-19 is spreading around the world. Information about its mechanism, prognostic factors, and management is minimal. COVID-19, as a human disease, has several identifying phases. Physicians of patients with COVID-19 may be interested in knowing whether opioid use disorder may affect their patients' course or prognosis. This information may be crucial when considering the opioid epidemic in the US and other parts of the world. Opioid use at high doses and over several months duration can mitigate the immune system's function, which may complicate the course of COVID-19 disease. Potential suppression of parts of the immune response may be important in prevention, clinical support, and therapeutic use of medications in various phases of the COVID-19. Specifically, opioid use disorders via an inhalation route may enhance the "late hyper-inflammatory phase" or result in end-organ damage. It is well established that opioids decrease ventilation as their effect on the medullary respiratory centers increases the risk of pneumonia. This increased risk has been associated with immune-suppressive opioids. The ultimate role of opioids in COVID-19 is not clear. This paper endorses the need for clinical studies to decipher the role and impact of chronic opioid use on viral diseases such as COVID-19.

The Role of Anesthetic Management in Surgical Site Infections After Pediatric Intestinal Surgery

BACKGROUND

Although surgical site infections (SSIs) remain a significant health care issue, a limited number of studies have analyzed risk factors for SSIs in children, particularly the role of intraoperative anesthetic management. Pediatric patients are less likely to have major adult risk factors for SSIs such as smoking and diabetes. Thus children may be more suitable as a cohort for examining the role of intraoperative anesthetics in SSIs.

AIM

We examined an association between SSI incidence and anesthetic management in children who underwent elective intestinal surgery in a single institution.

METHODS

We performed a retrospective study of 621 patients who underwent elective intestinal surgery under general anesthesia between January 2017 and September 2019, with primary outcome as the incidence of SSIs. We compared patients who were dichotomized in accordance with the median of the sevoflurane dose. We used propensity score (PS) pairwise matching of these patients to avoid selection biases. PS matching yielded 204 pairs of patients.

RESULTS

We found that higher doses of sevoflurane were associated with a higher incidence of SSIs (9.8% versus 3.9%, P = 0.019). We adjusted for intraoperative factors that were not included in the PS adjustment factors, and multivariate regression analysis after PS matching showed compatible results (odds ratio: 2.58, 95% confidence interval: 1.11-6.04, P = 0.028).

CONCLUSIONS

Higher doses of sevoflurane are associated with increased odds of SSIs after pediatric elective intestinal surgery. A randomized controlled study of volatile anesthetic-based versus intravenous anesthetic-based anesthesia will be needed to further determine the role of anesthetic drugs in SSI risk.

The Association Between Prescribed Opioid Receipt and Community-Acquired Pneumonia in Adults: a Systematic Review and Meta-analysis

BACKGROUND

In the current opioid epidemic, opioid addiction and overdose deaths are a public health crisis. Researchers have uncovered other concerning findings related to opioid use, such as the association between prescribed opioids and respiratory infection, including pneumonias. Potential mechanisms include the immunosuppressive effects of certain opioids, respiratory depression, and cough suppression. We conducted a systematic review assessing whether prescribed opioid receipt is a risk factor for community-acquired pneumonia (CAP).

METHODS

A systematic literature search of published studies was conducted using Ovid MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, Web of Science, AMED, and CINAHL from database inception through March 11, 2020. We included any clinical trial, cohort, or case-control study that reported an association between prescribed opioid receipt and CAP in adults. Two reviewers independently performed data extraction and quality assessment using the Newcastle-Ottawa Quality Assessment Scale. The risk of CAP from prescribed opioid receipt was studied by pooling studies using random effects meta-analysis.

RESULTS

We identified 3229 studies after removing duplicates. After detailed selection, 33 articles were reviewed in full and eight studies (representing 567,472 patients) met inclusion criteria. The pooled effect for the four case-control studies and three cohort studies showed a significant increase in the risk of CAP requiring hospitalization among those with prescribed opioid receipt compared with those without opioid prescribed receipt (OR 1.57 [95% CI (1.34, 1.84)]; HR 1.18 [95% CI (1.00, 1.40)]).

CONCLUSION

The findings suggest prescribed opioid receipt is a risk factor for CAP. The included studies examined post-operative patients and patients with chronic medical conditions. Further research is needed to examine the impact of opioids on the incidence of CAP in an otherwise healthy population.

Collaboration between a tertiary pain centre and community teams during the pandemic

People with chronic pain faced potential treatment disruption during the COVID-19 pandemic in Singapore, as the focus of healthcare shifted. A model of rapid integration of a pain centre with community healthcare teams was implemented to care for vulnerable older patients with chronic pain and multiple comorbidities. Telemedicine and home visits by community nurses were used, with risk-mitigation measures, ensuring comprehensive assessment and treatment compliance. Medications from pain physicians were delivered at home through a hospital pharmacy. A secure national electronic health records system used by all teams ensured seamless access and documentation. Potential emergency department visits, admissions and delayed discharges were thus avoided. Integration of community teams with chronic pain management services can be recommended to ensure pandemic preparedness.

Chronic Opioid Use and Risk of Cancer in Patients with Chronic Noncancer Pain: A Nationwide Historical Cohort Study

BACKGROUND

To investigate whether chronic opioid therapy is associated with a higher risk of cancer among noncancer patients with chronic pain.

METHODS

A population-based historical cohort study of the South Korean adult population was conducted using data from the National Health Insurance Service. We included patients registered with a diagnostic code of M00-M99 (musculoskeletal system and connective tissue diseases) according to the International Classification of Diseases, 10th revision, in 2010. Patients prescribed a continuous supply of any opioid drug for ≥90 days were defined as chronic opioid users.

RESULTS

A total of 351,701 patients were analyzed. Among them, 25,153 (7.2%) were chronic opioid users. Using a multivariate time-dependent Cox regression model, the risk of cancer in chronic opioid users was 1.20-fold higher than that in controls [HR, 1.20; 95% confidence interval (CI), 1.15-1.25; P < 0.001]. On subgroup analysis according to opioid potency, the cancer risk in chronic weak and strong opioid users was 1.18-fold (HR, 1.18; 95% CI, 1.13-1.23; P < 0.001) and 1.32-fold (HR, 1.32; 95% CI, 1.10-1.59; P = 0.003) higher than that in controls, respectively.

CONCLUSIONS

Chronic opioid therapy was associated with an increased risk of cancer among noncancer patients with chronic pain. This association was more evident in chronic strong opioid users. However, as unmeasured and potential confounders may have affected the results, the relationship between chronic opioid use and cancer risk should be evaluated with caution.

IMPACT

Chronic opioid therapy was associated with an increased risk of cancer among noncancer patients.

Clinical Challenges and Considerations in Management of Chronic Pain Patients During a COVID-19 Pandemic

Since the coronavirus disease 2019 (COVID-19) was deemed a pandemic on 11 March 2020, we have seen exponential increases in the number of cases and deaths worldwide. The rapidly evolving COVID-19 situation requires revisions to clinical practice to defer non-essential clinical services to allocate scarce medical resources to the care of the COVID-19 patient and reduce risk to healthcare workers. Chronic pain patients require long-term multidisciplinary management even during a pandemic. Fear of abandonment, anxiety and depression may increase during this period of social isolation and aggravate pain conditions.Whilst physical consults for chronic pain patients were reduced, considerations including continuity of support and analgesia, telemedicine, allied health support and prioritising necessary pain services and interventions, were also taken to ensure biopsychosocial care for them. Chronic pain patients are mostly elderly with multiple comorbidities, and are more susceptible to morbidity and mortality from COVID-19. It is imperative to review pain management practices during the COVID-19 era with respect to infection control measures, re-allocation of healthcare resources, community collaborations, and analgesic use and pain interventions. The chronic pain patient faces a potential risk of functional and emotional decline during a pandemic, increasing healthcare burden in the long term. Clinical decisions on pain management strategies should be based on balancing the risks and benefits to the individual patient. In this commentary, we aim to discuss the basis behind some of the decisions and safeguards that were made at our tertiary pain centre over the last 6 months during the COVID-19 outbreak.

Pain Management During the COVID-19 Pandemic

Chronic pain management during the coronavirus disease 2019 (COVID-19) pandemic is a challenging process, especially with growing evidence that COVID-19 infection is associated with myalgias, referred pain, and widespread hyperalgesia. In light of the limited data available for COVID-19-related impact on chronic pain patients, this review explores the changes in the healthcare delivery system due to social distancing and safety precautions to provide the appropriate management of chronic pain patients during the COVID-19 pandemic. Understanding both the general problems facing chronic pain patients as well as specific problems in the COVID-19 era including deconditioning, increased mental health concerns, financial burdens, and potential for medication-induced immune-suppression is vital in the appropriate management of patients. Telemedicine, the practice of caring for patients remotely when the provider and patient are not physically present with each other, is becoming increasingly used and recognized as a valuable tool to both health care providers and patients. This paper concentrates on the proper utilization of the available resources to help patients with the most severe conditions as well as the most vulnerable group. COVID-19 may be associated with a profound effect on both the health care system and patients with chronic pain. As a result, delaying, or stopping, treatment for chronic pain patients will have negative consequences, and strong pain evaluations must be administered to triage patients appropriately. Recent recommendations for the safe use of non-opioid analgesics, opioid analgesics, and interventional pain management procedures are vital to know and understand specifically during the pandemic era. Further researches are needed to identify the advance planning and rapid responses to reduce the impact of the pandemic.

The impact of the COVID-19 pandemic on patients awaiting spinal cord stimulation surgery in the United Kingdom: a multi-centre patient survey

Introduction

Spinal cord stimulation (SCS) is a recommended treatment for chronic refractory neuropathic pain. During the COVID-19 pandemic, elective procedures have been postponed indefinitely both to provide capacity to deal with the emergency caseload and to avoid exposure of elective patients to COVID-19. This survey aimed to explore the effect of the pandemic on chronic pain in this group and the views of patients towards undergoing SCS treatment when routine services should resume.

Methods

This was a prospective, multi-centre telephone patient survey that analysed data from 330 patients with chronic pain who were on an SCS waiting list. Questions focussed on severity of pain, effect on mental health, medication consumption and reliance on support networks during the COVID-19 pandemic. Views towards undergoing SCS therapy were also ascertained. Counts and percentages were generated, and chi-square tests of independence explored the impact of COVID-19 risk (very high, high, low) on survey responses.

Results

Pain, mental health and patient's ability to self-manage pain deteriorated in around 47%, 50% and 38% of patients, respectively. Some patients reported increases in pain medication consumption (37%) and reliance on support network (41%). Patients showed a willingness to attend for COVID-19 testing (92%), self-isolate prior to SCS (94%) and undergo the procedure as soon as possible (76%).

Conclusion

Our findings suggest that even during the COVID-19 pandemic, there remains a strong clinical need for patients with chronic pain identified as likely SCS responders to be treated quickly. The current prioritisation of new SCS at category 4 (delayed more than 3 months) is challenged judging by this national survey. These patients are awaiting SCS surgery to relieve severe intractable neuropathic pain. A priority at category 3 (delayed up to 3 months) or in some selected cases, at category 2 are the appropriate priority categories.

Opioid free anesthesia: evidence for short and long-term outcome

The introduction of synthetic opioids in clinical practice played a major role in the history of anesthesiology. For years, anesthesiologists have been thinking that opioids are needed for intraoperative anesthesia. However, we now know that opioids (especially synthetic short-acting molecules) are definitely not ideal analgesics and may even be counterproductive, increasing postoperative pain. As well, opioids have revealed important drawbacks associated to poor perioperative outcomes. As a matter of fact, efforts in postoperative pain management in the last 30 years were driven by the idea of reducing/eliminating opioids from the postoperative period. However, a modern concept of anesthesia should eliminate opioids already intra-operatively towards a balanced, opioid-free approach (opioid-free anesthesia - OFA). In OFA drugs and techniques historically proven for their efficacy are combined in rational and defined protocols. They include ketamine, alpha-2 agonists, lidocaine, magnesium, anti-inflammatory drugs and regional anesthesia. Promising results have been obtained on perioperative outcome. For sure, analgesia is not reduced with OFA, but it is effective and with less opioid-related side effects. These benefits may be of particular importance in some high-risk patients, like OSAS, obese and chronic opioid-users/abusers. OFA may also increase patient-reported outcomes; despite it is difficult to specifically rule out the effect of intraoperative opioids. Finally, few data are available on long-term outcomes (persistent pain and opioid abuse, cancer outcome). New studies and data are required to elaborate the optimal approach for each patient/surgery, but interest and publication are increasing and may open the road to the wider adoption of OFA.

Preoperative opioid use and incidence of surgical site infection after repair of ventral and incisional hernias

BACKGROUND

Preoperative opioid use is a risk factor for complications after some surgical procedures. The purpose of this study was to investigate the influence of preoperative opiates on outcomes after ventral hernia repair.

METHODS

With institutional review board approval, we conducted a retrospective review of consecutive ventral hernia repair cases during a 4-y period.

RESULTS

A striking 48% of the total 234 patients met criteria for preoperative opioid use. Preoperative characteristics and operative details were similar between patient groups (preoperative opioid use versus no preoperative opioid use). Median duration of hospital stay trended toward an increase for opioid users versus nonopioid users (P = .06). Return of bowel function was delayed in opioid users compared with nonopioid users (P = .018). Incidence of superficial surgical site infection was increased among patients who used opioids preoperatively (27% vs 8.3%; P <.001) and remained so after multivariable logistic regression, (adjusted odds ratio 2.9, 95% confidence interval 1.2-6.7; P = .013).

CONCLUSION

Among patients undergoing ventral hernia repair, those with preoperative opioid use experienced an increased incidence of superficial surgical site infection compared with patients without preoperative opioid use. Further study is needed to understand the relationship between opioid use and surgical site infection after ventral hernia repair.

Genetics and Opioids: Towards More Appropriate Prescription in Cancer Pain

Opioids are extensively used in patients with cancer pain; despite their efficacy, several patients can experience ineffective analgesia and/or side effects. Pharmacogenetics is a new approach to drug prescription based on the “personalized-medicine” concept, i.e., the ability of tailoring treatments to each individual’s genetic/genomic profile. Pharmacogenetics aims to identify specific genetic variants that influence pharmacokinetics and pharmacodynamics of drugs, better determining their effectiveness/safety profile. Opioid response is a complex scenario, but some gene variants have shown a correlation with pain sensitivity, as well as with opioid metabolism and clinical efficacy/adverse events. Although questions remain unanswered, some of these gene variants may already be used to identify specific patients’ phenotypes that are more prone to experience better clinical response (i.e., better analgesia and/or less adverse events). Once adopted, this approach to opioid prescription may improve a patient’s outcome. This review summarizes the available data on genetic variants and opioid response: we will focus on basic pharmacogenetic and its impact in the clinical scenario discussing how they may lead to more appropriate opioid prescription in cancer patients.

Five-year mortality trends associated with chronic pancreatitis in South Korea: A population based cohort study

BACKGROUND

Chronic pancreatitis (CP) is associated with all-cause and cancer-related mortality; however, the risk of mortality associated with alcoholic and non-alcoholic CP remains controversial. This study investigated whether CP increased the risk of 5-year all-cause and cancer-specific mortality compared to a control population.

METHODS

This population-based study used data from a sample cohort of the National Health Insurance Service (NHIS) database in South Korea. CP was defined as disease code K86.0 (alcohol-induced CP) and K86.1 (other CP and non-alcoholic CP) from the tenth edition of the International Classification of Diseases.

RESULTS

The prevalence of chronic alcoholic pancreatitis increased from 0.01% in 2002 to 0.07% in 2015, and the prevalence of chronic non-alcoholic pancreatitis increased from 0.08% in 2002 to 0.50% in 2015. In the 2010 NHIS cohort (n = 826,909), CP was associated with an increased risk of 5-year all-cause mortality (hazard ratio [HR] = 1.25, 95% confidence interval [CI]: 1.25 to 1.66, P < 0.001). Additionally, non-alcoholic CP was associated with an increased risk of 5-year all-cause mortality (HR = 1.47, 95% CI: 1.27 to 1.71, P < 0.001); in contrast, alcohol-induced CP was not significantly associated with mortality risk (P = 0.569). Similar tendencies were observed for the 5-year cancer-related mortality risk.

CONCLUSIONS

In South Korea, the prevalence of alcoholic and non-alcoholic CP increased during 2002-2015. CP may be an independent risk factor for 5-year all-cause and cancer-related mortality. In this study, this association was more evident in patients with non-alcoholic CP.

Characterizing the risk and outcome profiles of lumbar fusion procedures in patients with opioid use disorders: a step toward improving enhanced recovery protocols for a unique patient population

OBJECTIVEThe authors set out to conduct the first national-level study assessing the risks and outcomes for different lumbar fusion procedures in patients with opioid use disorders (OUDs) to help guide the future development of targeted enhanced recovery after surgery (ERAS) protocols for this unique population.METHODSData for patients with or without OUDs who underwent an anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), or lateral transverse lumbar interbody fusion (LLIF) for lumbar disc degeneration (LDD) were collected from the 2013-2014 National (Nationwide) Inpatient Sample database. Multivariable logistic regression was implemented to analyze how OUD status impacted in-hospital complications, length of hospital stay, discharge disposition, and total charges by procedure type.RESULTSA total of 139,995 patients with LDD were identified, with 1280 patients (0.91%) also having a concurrent OUD diagnosis. Overall complication rates were higher in OUD patients (48.44% vs 31.01%, p < 0.0001). OUD patients had higher odds of pulmonary (p = 0.0006), infectious (p < 0.0001), and hematological (p = 0.0009) complications. Multivariate regression modeling of outcomes by procedure type showed that after ALIF, OUD patients had higher odds of nonhome discharge (p = 0.0007), extended hospitalization (p = 0.0002), and greater total charges (p = 0.0054). This analysis also revealed that OUD patients faced higher odds of complication (p = 0.0149 and p = 0.0471), extended hospitalization (p = 0.0439 and p = 0.0001), and higher total charges (p < 0.0001 and p < 0.0001) after PLIF and LLIF procedures, respectively.CONCLUSIONSObtaining a better understanding of the risks and outcomes that OUD patients face perioperatively is a necessary step toward developing more effective ERAS protocols for this vulnerable population. This study, which sought to characterize the outcome profiles for lumbar fusion procedures in OUD patients on a national level, found that this population tended to experience increased odds of complications, extended hospitalization, nonhome discharge, and higher total costs. Results from this study warrant future prospective studies to better the understanding of these associations and to further the development of better ERAS programs that may improve patient care and reduce cost burden.

Opioids and Cancer Mortality

OPINION STATEMENT

Opioids are the gold standard for the treatment of cancer-related pain. Preclinical studies have associated opioids with cancer progression and overall survival. In mice models, opioids have been shown to possess pro-tumor activity secondary to immunosuppression, migration of tumor cells, increased activity of vascular endothelial growth factor receptors, and angiogenesis leading to tumor progression. In contrast, opioids have also been associated with having antitumor activity by activation of apoptosis and phagocytosis. However, high-quality randomized controlled trials in humans that are focused on the association between opioids and survival in cancer patients are lacking, which underscores the importance of being cautious when interpreting the results of the preclinical studies. Cancer-related pain is complex and multifactorial and may worsen as the disease progresses leading to higher opioid utilization. Moreover, cancer pain by itself has been associated with poor survival. The survival in these advanced cancer patients taking opioids may be more likely to be associated with cancer progression and not the opioid use. Adequate treatment of cancer pain has the potential to improve quality of life and performance status, highlighting the importance of continuing to use opioids to manage pain efficiently. More research is clearly needed.

Quantitative and Qualitative Behavioral Measurements to Assess Pain in Axolotls (Ambystoma mexicanum)

Effective pain relief in animals relies on the ability to discern pain and assess its severity. However, few objective measures exist to assess the presence and severity of pain in axolotls, and few resources are available regarding drugs and appropriate doses to provide pain relief in this species. This study evaluated behavioral tools for cageside pain assessment and validated a reproducible and reliable quantitative method to evaluate analgesic efficacy in axolotls. Animals were divided into control and treatment groups (n = 6 per group); treatment groups received buprenorphine through injection (50 mg/kg every 24 h for 48 h intracelomically) or butorphanol immersion (0.50 or 0.75 mg/L every 24 h for 48 h). Qualitative behavioral tests, adapted from other amphibian studies, included tapping on the home tank, directing water jets or physically touching specific anatomic points on the animal, and placing a novel object in the home tank. Quantitative methods used to produce noxious stimuli were the acetic acid test and von Frey aesthesiometers. Animals that were treated with analgesics did not demonstrate a significant difference compared with controls during behavioral assessment at 1, 6, 12, 25, 30, and 48 h after analgesia administration. The acetic acid test revealed a reproducible, concentration-dependent pain response. However, a significant difference in the AAT response was not observed between control and treated groups with the tested analgesics and doses.

Kinetic Modelling of [68Ga]Ga-DOTA-Siglec-9 in Porcine Osteomyelitis and Soft Tissue Infections

BACKGROUND

[⁶⁸Ga]Ga-DOTA-Siglec-9 is a positron emission tomography (PET) radioligand for vascular adhesion protein 1 (VAP-1), a protein involved in leukocyte trafficking. The tracer facilitates the imaging of inflammation and infection. Here, we studied the pharmacokinetic modelling of [⁶⁸Ga]Ga-DOTA-Siglec-9 in osteomyelitis and soft tissue infections in pigs.

METHODS

Eight pigs with osteomyelitis and soft tissue infections in the right hind limb were dynamically PET scanned for 60 min along with arterial blood sampling. The fraction of radioactivity in the blood accounted for by the parent tracer was evaluated with radio-high-performance liquid chromatography. One- and two-tissue compartment models were used for pharmacokinetic evaluation. Post-mortem soft tissue samples from one pig were analysed with anti-VAP-1 immunofluorescence. In each analysis, the animal's non-infected left hind limb was used as a control.

RESULTS

Tracer uptake was elevated in soft tissue infections but remained low in osteomyelitis. The kinetics of [⁶⁸Ga]Ga-DOTA-Siglec-9 followed a reversible 2-tissue compartment model. The tracer metabolized quickly; however, taking this into account, produced more ambiguous results. Infected soft tissue samples showed endothelial cell surface expression of the Siglec-9 receptor VAP-1.

CONCLUSION

The kinetics of [⁶⁸Ga]Ga-DOTA-Siglec-9 uptake in porcine soft tissue infections are best described by the 2-tissue compartment model.

The rising crisis of illicit fentanyl use, overdose, and potential therapeutic strategies

Fentanyl is a powerful opioid anesthetic and analgesic, the use of which has caused an increasing public health threat in the United States and elsewhere. Fentanyl was initially approved and used for the treatment of moderate to severe pain, especially cancer pain. However, recent years have seen a growing concern that fentanyl and its analogs are widely synthesized in laboratories and adulterated with illicit supplies of heroin, cocaine, methamphetamine, and counterfeit pills, contributing to the exponential growth in the number of drug-related overdose deaths. This review summarizes the recent epidemic and evolution of illicit fentanyl use, its pharmacological mechanisms and side effects, and the potential clinical management and prevention of fentanyl-related overdoses. Because social, economic, and health problems that are related to the use of fentanyl and its analogs are growing, there is an urgent need to implement large-scale safe and effective harm reduction strategies to prevent fentanyl-related overdoses.

Opioid use trajectory groups and changes in a physical health biomarker among HIV-positive and uninfected patients receiving opioid agonist treatment

BACKGROUND

Objective outcomes for measuring the physical health effects of substance use disorder treatment are needed. We compared the responsiveness of CD4, HIV-1 RNA and a biomarker index (VACS Index 2.0) to changes in opioid use among people with HIV (PWH) and uninfected individuals receiving opioid agonist treatment (OAT).

METHODS

Electronic health record data were used to identify patients who received ≥90 days of OAT and had ≥1 urine toxicology test in the Veterans Aging Cohort Study. Trajectory models identified patterns of opioid urine toxicology results. We used linear regression adjusted for age and race/ethnicity to determine associations between opioid toxicology groups and biomarker changes from up to one-year pre OAT to 3-15 months after OAT initiation.

RESULTS

Among 266 with detectable HIV-1 RNA, 366 with suppressed HIV-1 RNA, and 1183 uninfected patients, we identified five opioid toxicology groups ranging from consistently negative (54%) to consistently positive (9%). Among PWH with detectable HIV-1 RNA, all three biomarkers improved more for those consistently negative compared to those consistently positive (all p < .05). Among PWH with suppressed HIV-1 RNA, CD4 improved for those consistently negative; and worsened for those in the slow decrease toward negative group (p = .04). Among those uninfected, VACS Index 2.0 did not differ by opioid toxicology groups.

CONCLUSIONS

Among patients on OAT, changes in biomarkers are associated with opioid toxicology groups among PWH, but vary by HIV-1 RNA. These findings may be useful for measuring the health effects of OAT.

Neuroimmune mechanisms of psychostimulant and opioid use disorders

Substance use disorders are global health problems with few effective treatment options. Unfortunately, most potential pharmacological treatments are hindered by abuse potential of their own, limited efficacy, or adverse side effects. As a consequence, there is a pressing need for the development of addiction treatments with limited abuse potential and fewer off target effects. Given the difficulties in developing new pharmacotherapies for substance use disorders, there has been growing interest in medications that act on non-traditional targets. Recent evidence suggests a role for dysregulated immune signaling in the pathophysiology of multiple psychiatric diseases. While there is evidence that immune responses in the periphery and the central nervous system are altered by exposure to drugs of abuse, the contributions of neuroimmune interactions to addictive behaviors are just beginning to be appreciated. In this review, we discuss the data on immunological changes seen in clinical populations with substance use disorders, as well as in translational animal models of addiction. Importantly, we highlight those mechanistic findings showing causal roles for central or peripheral immune mediators in substance use disorder and appropriate animal models. Based on the literature reviewed here, it is clear that brain-immune system interactions in substance use disorders are much more complex and important than previously understood. While much work remains to be done, there are tremendous potential therapeutic implications for immunomodulatory treatments in substance use disorders.