Postoperative opioids, endocrine changes, and immunosuppression

Risk of infections among persons treated with opioids for chronic pain: a systematic review and meta-analysis protocol

INTRODUCTION

Millions of persons with chronic pain across North America and Europe use opioids. While the immunosuppressive properties of opioids are associated with risks of infections, these outcomes could be mitigated through careful patient selection and monitoring practices when appropriate. It is important to recognise that some patients do benefit from a carefully tailored opioid therapy. Enough primary studies have been published to date regarding the role of opioids in potential immunosuppression presenting as an increased rate of infection acquisition, infectious complications and mortality. There is thus a critical need for a consensus in this area.

METHODS AND ANALYSIS

The methodology is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, the MOOSE Guidelines for Meta-Analyses and Systematic Reviews of Observational Studies and the Cochrane Handbook for Systematic Reviews of Interventions. We plan to systematically search Ovid MEDLINE, CINAHL, PsycINFO, EMB Review, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials and Google Scholar databases from their inception date to December 2023. Full-text primary studies that report measurable outcomes in adults with chronic pain, all routes of opioid use, all types of infections and all settings will be included. We will identify a scope of reported infections and the evidence on the association of opioid use (including specific opioid, dosage, formulation and duration of use) with the risk of negative infectious outcomes. Opioid use-associated outcomes, comparing opioid use with another opioid or a non-opioid medication, will be reported. The meta-analysis will incorporate individual risk factors. If data are insufficient, the results will be synthesised narratively. Publication bias and confounding evaluation will be performed. The Grading of Recommendations Assessment, Development and Evaluation framework will be used.

ETHICS AND DISSEMINATION

Approval for the use of published data is not required. The results will be published, presented at conferences and discussed in deliberative dialogue groups.

PROSPERO REGISTRATION NUMBER

CRD42023402812.

The Surgical Stress Response and Anesthesia: A Narrative Review

The human physiological response "to stress" includes all metabolic and hormonal changes produced by a traumatic event at the micro or macro cellular levels. The main goal of the body's first response to trauma is to keep physiological homeostasis. The perioperative non-specific adaptation response can sometimes be detrimental and can produce systemic inflammatory response syndrome (SIRS), characterized by hypermetabolism and hyper catabolism. We performed a narrative review consisting of a description of the surgical stress response's categories of changes (neurohormonal and immunological response) followed by reviewing methods found in published studies to modulate the surgical stress response perioperatively. We described various preoperative measures cited in the literature as lowering the burden of surgical trauma. This article revises the anesthetic drugs and techniques that have an impact on the surgical stress response and proven immune-modulatory effects. We also tried to name present knowledge gaps requiring future research. Our review concludes that proper preoperative measures, adequate general anesthetics, multimodal analgesia, early postoperative mobilization, and early enteral nutrition can decrease the stress response to surgery and ease patient recovery. Anesthetics and analgesics used during the perioperative period may modulate the innate and adaptive immune system and inflammatory system, with a consecutive impact on cancer recurrence and long-term outcomes.

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.

Ultrasound assessment of residual gastric volume in older adults undergoing staged-bilateral total knee arthroplasty after consuming carbohydrate-containing fluids: a prospective observational study

BACKGROUND

We compared preoperative residual gastric volume (GV) between the first and second stages of total knee arthroplasty (TKA) in older adults after drinking carbohydrate-containing fluid 2 h prior to surgery.

METHODS

In this study, 36 patients, aged > 65 years, scheduled for staged bilateral TKA with one-week interval, were enrolled. The patients consumed 400 ml of carbohydrate-containing fluid 2 h prior to surgery. Before the induction of spinal anesthesia, the gastric antral cross-sectional area was measured at the first and second TKA using ultrasound, and the residual GV was calculated. The primary outcome was the residual GV. Qualitative GV (grades 0, 1, and 2) and analgesic consumption after the first TKA were assessed as secondary outcomes.

RESULTS

The GV (median [Q1, Q3]) was greater in the second-stage TKA (41.1 [22.5, 62.8] ml) than in the first-stage TKA (10.3 [0.0, 27.1] ml) (P < 0.001). In the qualitative assessment, the distribution was not different between the two stages of TKA (P = 0.219) and only one patient showed grade 2 gastric content in the second TKA. When opioid consumption was converted to an equivalent dose of morphine, an average of 53.9 mg of morphine was required after the first TKA.

CONCLUSIONS

Residual GV after drinking carbohydrate-containing fluid differed according to the stage of TKA, showing a larger residual GV in the second TKA than in the first one. In older adults scheduled to undergo bilateral staged TKA, caution is required in preoperative fasting practice, especially in second-stage surgery.

Can Infusion of Lidocaine During Breast Cancer Surgery Promote Higher In-vitro Apoptosis in Comparison with Fentanyl?

Background: Although several numbers of the common anesthetic drugs are frequently used in breast cancer (BC) surgery, their possible effects on the behavior of cancer cells are still unknown. Objectives: The main objective of the present study was to examine the effect of administered lidocaine versus fentanyl during BC surgery on the apoptosis index of BC cells in-vitro. Methods: Patients with BC with the same grade of cancer and American Society of Anesthesiologists (ASA) score I–III, who underwent surgery were randomly divided into 2 groups of lidocaine and fentanyl infusion based on the analgesic drugs they received. Blood samples were drawn before and after the surgery and then cells from the BC cell line (MCF-7) were exposed to them at 24, 48, and 72 hours post-culture. Flow cytometry was performed to measure the mean percentage of apoptosis index; To investigate the cells’ viability, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was also applied. Results: Sixty patients were enrolled. Quantitative cell death analysis revealed that the proportion of apoptotic cells in both lidocaine and fentanyl groups significantly increased when the cells were treated with post-operation sera compared to pre-operation sera exposure at various time intervals. In both groups, intra-group cell death analysis showed that there was not any statistically significant difference among the cultured cells exposed to pre-operation sera at various interval times (P < 0.001) with respect to apoptosis and cell viability. Conclusions: The study findings proposed that lidocaine infusion can reach the apoptosis index of BC cells in-vitro, as much as that fentanyl did; and both drugs had significant effects.

Modifying the Stress Response - Perioperative Considerations and Controversies

The idea that perioperative outcomes may be improved through the implementation of measures that modify the surgical stress response has been around for several decades. Many techniques have been trialled with varying success. In addition, how the response to modification is measured, what constitutes a positive result and how this translates into clinical practice is the subject of debate. Modification of the stress response is the principal tenet behind the enhanced recovery after surgery (ERAS) movement which has seen the development of guidelines for perioperative care across a variety of surgical specialties bringing with them significant improvements in outcomes.

Continuous wound infusion with ropivacaine alone provides adequate analgesia following laparotomy

BACKGROUND

Although continuous wound infusion (CWI) with local anaesthetic has been used as an adjunct for pain relief following laparotomy, its use as the main modality has not been studied. This approach negates side effects related to intravenous opioid administration, therefore promoting enhanced recovery from surgery. We conducted this study to investigate the feasibility and efficacy of CWI following laparotomy.

METHODS

Consecutive patients who underwent laparotomy from June 2016 to December 2019 were analysed. All patients were given CWI with only oral supplementation. Pain was assessed based on the numeric rating scale (NRS).

RESULTS

One hundred and three patients were analysed. Mean age was 61.1 (standard deviation 16.7). 47.6% of patients were operated for intestinal obstruction. Large bowel resection was the most common operation performed (49.5%). 69.9% of patients underwent emergency surgery, whilst 51.5% of patients had surgery for cancer. On postoperative day 0, NRS was 3.2 (standard deviation (sd) 2.6) which decreased to 1.5 (sd 1.9) on day 3, and 1.1 (sd 1.8) on day 5. Mean time to flatus was 2.3 (sd 1.4) days, whilst mean time to first bowel movement was 3.1 (sd 1.7) days. Patients were able to commence ambulation by 2.5 (sd 1.8) days. Patients could tolerate a normal diet on day 3.9 (sd 3.3), and IV drip was removed on day 3.5 (sd 3.0). Mean length of stay was 9.1 (sd 6.9) days. Only two patients suffered from respiratory depression (1.9%) whilst five patients suffered from hypotension (4.9%). No patients had pruritus. 23.3% of patients had nausea or vomiting. Only one patient had a catheter-related complication which was easily addressed.

CONCLUSION

CWI provides adequate pain relief as the principle modality of analgesia after surgery, without opioid side effects.

Morphine-mediated release of miR-138 in astrocyte-derived extracellular vesicles promotes microglial activation

Opioids, such as morphine, are the mainstay for the management of postsurgical pain. Over the last decade there has been a dramatic increase in deaths related to opioid overdose. While opioid abuse has been shown to result in increased neuroinflammation, mechanism(s) underlying this process, remain less understood. In recent years, microRNAs have emerged as key mediators of gene expression regulating both paracrine signaling and cellular crosstalk. MiRNAs constitute the extracellular vesicle (EV) cargo and can shuttle from the donor to the recipient cells. Exposure of human primary astrocytes to morphine resulted in induction and release of miR-138 in the EVs isolated from conditioned media of cultured astrocytes. Released EVs were, in turn, taken up by the microglia, leading to activation of these latter cells. Interestingly, activation of microglia involved binding of the GUUGUGU motif of miR138 to the endosomal toll like receptor (TLR)7, leading, in turn, to cellular activation. These findings were further corroborated in vivo in wildtype mice wherein morphine administration resulted in increased microglial activation in the thalamus. In TLR7-/- mice on the other hand, morphine failed to induce microglial activation. These findings have ramifications for the development of EV-loaded anti-miRNAs as therapeutics for alleviating neuroinflammation in opioids abusers.

Effects of anesthetics on post-operative 3-month neuroendocrine function after endoscopic transsphenoidal non-functional pituitary adenoma surgery

BACKGROUND

Anesthetic techniques can affect perioperative neuroendocrine function. The objective of this study was to compare 3-month post-operative neuroendocrine functional outcomes between sevoflurane and propofol anesthesia in patients undergoing endoscopic transsphenoidal surgery (ETS) for removal of non-functional pituitary adenomas (NFPAs) retrospectively.

METHODS

Among 356 patients who underwent ETS for removal of NFPAs under sevoflurane-remifentanil anesthesia (sevoflurane group, n = 103) or propofol-remifentanil anesthesia (propofol group, n = 253), 92 patients in each group were selected and their 3-month post-operative neuroendocrine functional outcomes (primary outcome measure) were compared after propensity score matching.

RESULTS

Overall changes in post-operative 3-month neuroendocrine function compared to pre-operative baseline did not differ between the sevoflurane and propofol groups (worsened: 32.6% vs 29.3%, persistently decreased: 9.8% vs 12.0%, improved: 12.0% vs 20.7%, normalized: 9.8% vs 12.0%, persistently normal: 18.5% vs 19.6%; P = .400). The incidence of pituitary hormone deficiency at 3 months post-operatively did not differ between the sevoflurane and propofol groups (adrenocorticotropic hormone deficiency: 18.5% vs 17.4%, P = 1.000; thyroid-stimulating hormone deficiency: 10.9% vs 3.3%, P = .081; gonadotropin deficiency: 54.3% vs 48.9%, P = .555; growth hormone deficiency: 45.7% vs 48.9%, P = .768; panhypopituitarism: 1.1% vs 1.1%, P = 1.000).

CONCLUSION

In patients undergoing ETS for removal of NFPAs, the effects of both sevoflurane-remifentanil and propofol-remifentanil anesthetic techniques on post-operative 3-month neuroendocrine functional outcomes were similar, suggesting that propofol and sevoflurane can be freely used in such patients in terms of post-operative intermediate-term neuroendocrine functional outcome.

The Association Between Potential Opioid-Related Adverse Drug Events and Outcomes in Total Knee Arthroplasty: A Retrospective Study

INTRODUCTION

Characterization of the clinical and economic impact of opioid-related adverse drug events (ORADEs) after total knee arthroplasty (TKA) may guide provider and hospital system approach to managing postoperative pain after TKA. Our analysis quantifies the rate of potential ORADEs after TKA, the impact of potential ORADEs on length of stay (LOS) and hospital revenue, as well as their association with specific patient risk factors and comorbid clinical conditions.

METHODS

We conducted a retrospective study using the Centers for Medicare and Medicaid Services administrative database to analyze Medicare discharges involving two knee replacement surgery diagnosis-related groups (DRGs) in order to identify potential ORADEs. The impact of potential ORADEs on mean hospital LOS and hospital revenue was analyzed.

RESULTS

The potential ORADE rate in patients who underwent TKA was 25,523 out of 316,858 records analyzed (8.0%). The mean LOS for patients who experienced a potential ORADE was 1.04 days longer than those without an ORADE. The mean hospital revenue per day with a potential ORADE was $1334 (USD) less than without an ORADE. Potential ORADEs were significantly associated with poor patient outcomes such as pneumonia, septicemia, and shock.

CONCLUSION

Potential ORADEs in TKA are associated with longer hospitalizations, decreased hospital revenue, and poor patient outcomes. Certain risk factors may predispose patients to experiencing an ORADE, and thus perioperative pain management strategies that reduce the frequency of ORADEs particularly in at-risk patients can improve patient satisfaction and increase hospital revenue following TKAs.

Opioid-induced immunosuppression and carcinogenesis promotion theories create the newest trend in acute and chronic pain pharmacotherapy

Opioids are the main group of pharmacological agents used during the perioperative period and provide a sedative and analgesic component. The observations of opioid consumption in West Europe indicate that this group of drugs is widely used in chronic noncancer pain therapy. Nearly 20 years ago, the first publications indicating that opioids, as an element of perioperative pharmacotherapy in oncologic patients, increase the risk of tumor recurrence and affect further prognosis were presented. The actual publications suggest that there are multifactorial, complex mechanisms underlying the immunological impact and carcinogenesis promotion of opioids and that the intensity varies depending on the type of opioid. There are also questions about the immunosuppressive effects among patients receiving opioids in the treatment of chronic noncancer pain. The aim of the review article is to present information about the action of opioids on the immune system in carcinogenic settings and to define the clinical usefulness of this pharmacological phenomenon.

Potential opioid-related adverse events following spine surgery in elderly patients

OBJECTIVE

Understanding the clinical and economic impact of opioid-related adverse drug events (ORADEs) within spine surgery may guide both the clinician's and hospital administration's approach to treating perioperative pain, thus improving patient care and reducing hospital costs. The objective of this analysis is to understand how potential ORADEs after spine surgery in elderly patients affect length of stay, hospital revenue and their association with comorbid conditions.

PATIENTS AND METHODS

We conducted a retrospective study utilizing the Center for Medicare/Medicaid Services Administrative Database to analyze Medicare discharges between April 2016 and March 2017 involving 14 spine surgery DRGs for major spine procedures in order to identify potential ORADEs. An analysis was conducted using this database to identify the incidence of potential ORADEs as well as their impact on mean hospital length of stay and hospital revenue.

RESULTS

There were 177,432 discharges during the study period. The ORADE rate in patients undergoing spine surgery was 13.9% (24,642/177,432). The mean length of stay (LOS) for discharges with an ORADE was 3.13 days longer than without an ORADE (6.29 days with an ORADE vs 3.16 days without an ORADE). The adverse post-operative outcomes most strongly associated with potential ORADEs included shock, pneumonia, and septicemia. The mean hospital revenue per day with an ORADE was $3,076 less than without an ORADE ($7,263 with an ORADE vs $10,339 without an ORADE).

CONCLUSION

Potential ORADEs in spine surgery in elderly patients are common and are associated with longer hospitalizations and decreased hospital revenue. Perioperative pain management strategies that reduce ORADEs may improve patient care and increase hospital revenue.

Procedure-Specific Pain Management (PROSPECT) - An update

Post-operative pain management protocols may be optimised by examining procedure-specific evidence and outcomes. This recognition led to the formation of the PROcedure-SPECific Pain ManagemenT (PROSPECT) collaboration of anaesthesiologists and surgeons. The aim of PROSPECT is to provide practical and evidence-based recommendations to prevent and treat post-operative pain after specific surgical procedures, thereby overcoming the limitations of generic, non-specific guidelines. Updates in the methodology of PROSPECT in 2017 have placed an increased emphasis on the clinical relevance of studies, including a focus on interventions in the context of multimodal analgesia strategies and consideration of risks and benefits of interventions in specific surgical settings. Evidence-based reviews of analgesic measures, including advice on surgical techniques and adjuvants after diverse surgical procedures, have been completed by the PROSPECT collaboration and are accessible on the website (www.postoppain.org) and published in the peer-reviewed literature. These reviews continue to identify significant gaps in clinically relevant research on post-operative analgesia and are possibly leading to a closing of some of these gaps.