Dexmedetomidine in perioperative acute pain management: a non-opioid adjuvant analgesic

Dexmedetomidine for enhanced recovery after non-intubated video-assisted thoracoscopic surgery

BACKGROUND

Non-intubated video-assisted thoracoscopic surgery combines a minimally invasive technique with multimodal locoregional analgesia to enhance recovery. The mainstay sedation protocol involves propofol and fentanyl. Dexmedetomidine, given its opioid-sparing effect with minimal respiratory depression, facilitates sedation in non-intubated patients. This study aimed to evaluate the efficacy of dexmedetomidine during non-intubated video-assisted thoracoscopic surgery.

METHODS

A total of 114 patients who underwent non-intubated video-assisted thoracoscopic surgery between June 2015 and September 2017 were retrospectively evaluated. Of these, 34 were maintained with dexmedetomidine, propofol, and fentanyl, and 80 were maintained with propofol and fentanyl. After a 1:1 propensity score-matched analysis incorporating sex, body mass index, American Society of Anesthesiologists classification, pulmonary disease and hypertension, the clinical outcomes of 34 pairs of patients were assessed.

RESULTS

The dexmedetomidine group showed a significantly lower opioid consumption [10.3 (5.7-15.1) vs. 18.8 (10.0-31.0) mg, median (interquartile range); P = 0.001] on postoperative day 0 and a significantly shorter postoperative length of stay [3 (2-4) vs. 4 (3-5) days, median (interquartile range), P = 0.006] than the control group. During operation, the proportion of vasopressor administration was significantly higher in the dexmedetomidine group [18 (53) vs. 7 (21), patient number (%), P = 0.01]. On the other hand, the difference of the hypotension and bradycardia incidence, short-term morbidity and mortality rates between each group were nonsignificant.

CONCLUSION

Adding adjuvant dexmedetomidine to propofol and fentanyl is safe and feasible for non-intubated video-assisted thoracoscopic surgery. With its opioid-sparing effect and shorter postoperative length of stay, dexmedetomidine may enhance recovery after surgery.

Assessing suicide risk in chronic pain management: a narrative review across drug classes

INTRODUCTION

Chronic pain presents a multifaceted challenge in clinical practice, necessitating a nuanced understanding of pharmacological interventions to optimize treatment outcomes. This review provides an outline of various pharmacological agents commonly used in chronic pain management and highlights their safety considerations, particularly regarding suicide risk.

AREAS COVERED

This review discusses the role of antidepressants, anticonvulsants, GABA receptor agonists, NMDA receptor antagonists, corticosteroids, cannabis and cannabinoids, bisphosphonates, calcitonin, and alpha-2 adrenergic receptor agonists in chronic pain management. It assesses their therapeutic benefits, potential for misuse, and psychiatric adverse effects, including the risk of suicide. Each pharmacological class is evaluated in terms of its efficacy, safety profile, and considerations for clinical practice. We searched peer-reviewed English literature on the topic using the MEDLINE database without time restrictions.

EXPERT OPINION

While pharmacological interventions offer promise in alleviating chronic pain, healthcare providers must carefully weigh their benefits against potential risks, including the risk of exacerbating psychiatric symptoms and increasing suicide risk. Individualized treatment approaches, close monitoring, and multidisciplinary collaboration are essential for optimizing pain management strategies while mitigating adverse effects. Ongoing research efforts are crucial for advancing our understanding of these pharmacological interventions and refining pain management practices.

The Role of Intravenous Anesthetics for Neuro: Protection or Toxicity?

The primary intravenous anesthetics employed in clinical practice encompass dexmedetomidine (Dex), propofol, ketamine, etomidate, midazolam, and remimazolam. Apart from their established sedative, analgesic, and anxiolytic properties, an increasing body of research has uncovered neuroprotective effects of intravenous anesthetics in various animal and cellular models, as well as in clinical studies. However, there also exists conflicting evidence pointing to the potential neurotoxic effects of these intravenous anesthetics. The role of intravenous anesthetics for neuro on both sides of protection or toxicity has been rarely summarized. Considering the mentioned above, this work aims to offer a comprehensive understanding of the underlying mechanisms involved both in the central nerve system (CNS) and the peripheral nerve system (PNS) and provide valuable insights into the potential safety and risk associated with the clinical use of intravenous anesthetics.

Dexmedetomidine and surgical field visibility in nasal surgery: A systematic review and meta-analysis

INTRODUCTION

Nasal and sinus surgery, especially using endoscopy, relies upon adequate haemostasis to be safe and effective. Often other haemostatic methods, such as cautery are not viable, and other methods must be employed. This study examines the effectiveness of dexmedetomidine in controlled hypotension and for surgical field visibility in endoscopic sinus surgery and other nasal surgeries.

REVIEW METHODS

A literature search was conducted in PubMed, Scopus, CINAHL and Central for randomised controlled trials using dexmedetomidine for controlled hypotension in adult patients undergoing endoscopic sinus surgery or other nasal surgery. Meta-analysis of mean differences and single means were performed.

RESULTS

Of 935 identified studies, 31 met the inclusion criteria. A statistically significant difference in Fromme-Boezaart surgical field visibility scores was found comparing dexmedetomidine to placebo (p < 0.00001) and propofol (p < 0.0001), but not other agents. A significant difference in intraoperative blood loss volume was found compared with placebo (51.5mL, p < 0.00001) and propofol (13.6mL, p < 0.0001), but not other agents.

CONCLUSION

Dexmedetomidine demonstrated significantly improved surgical field visibility and blood loss volume compared with placebo and propofol, but not other agents. Dexmedetomidine is viable and useful for controlled hypotension in nasal surgery. Choice of controlled hypotension agent should follow patient and procedure-specific considerations.

Combined Dexamethasone and Dexmedetomidine as Adjuncts to Popliteal and Saphenous Nerve Blocks in Patients Undergoing Surgery of the Foot or Ankle: A Randomized, Blinded, Placebo-controlled Clinical Trial

BACKGROUND

Both dexamethasone and dexmedetomidine increase the duration of analgesia of peripheral nerve blocks. The authors hypothesized that combined intravenous dexamethasone and intravenous dexmedetomidine would result in a greater duration of analgesia when compared with intravenous dexamethasone alone and placebo.

METHODS

The authors randomly allocated participants undergoing surgery of the foot or ankle under general anesthesia and with a combined popliteal (sciatic) and saphenous nerve block to a combination of 12 mg dexamethasone and 1 µg/kg dexmedetomidine, 12 mg dexamethasone, or placebo (saline). The primary outcome was the duration of analgesia measured as the time from block performance until the first sensation of pain in the surgical area as reported by the participant. The authors predefined a 33% difference in the duration of analgesia as clinically relevant.

RESULTS

A total of 120 participants from two centers were randomized and 119 analyzed for the primary outcome. The median [interquartile range] duration of analgesia was 1,572 min [1,259 to 1,715] with combined dexamethasone and dexmedetomidine, 1,400 min [1,133 to 1,750] with dexamethasone alone, and 870 min [748 to 1,138] with placebo. Compared with placebo, the duration was greater with combined dexamethasone and dexmedetomidine (difference, 564 min; 98.33% CI, 301 to 794; P < 0.001) and with dexamethasone (difference, 489 min; 98.33% CI, 265 to 706; P < 0.001). The prolongations exceeded the authors' predefined clinically relevant difference. The duration was similar when combined dexamethasone and dexmedetomidine was compared with dexamethasone alone (difference, 61 min; 98.33% CI, -222 to 331; P = 0.614).

CONCLUSIONS

Dexamethasone with or without dexmedetomidine increased the duration of analgesia in patients undergoing surgery of the foot or ankle with a popliteal (sciatic) and saphenous nerve block. Combined dexamethasone and dexmedetomidine did not increase the duration of analgesia when compared with dexamethasone.

EDITOR’S PERSPECTIVE

Dexmedetomidine in Palliative Care: A Versatile New Weapon Against Delirium and Pain-Systematic Review

Introduction: At the end of life, the prevalence of delirium and pain is high. Current therapy is not satisfactory. Dexmedetomidine could be useful in the control of delirium and pain but is not approved outside of intensive care setting. Our objectives are to evaluate existing evidence in the literature that assessed the efficacy of dexmedetomidine in pain and delirium control and its safety in palliative care patients outside intensive care units. This systematic review was prospectively registered with PROSPERO and included a risk of bias assessment. Methods: PubMed and SCOPUS were examined for literature published until 2023. Experimental, cohort, cross-sectional, case-control studies, and case series/reports were included if they evaluate the use of dexmedetomidine in delirium and/or pain management in hospitalized palliative care adult patients. Studies were excluded if they were carried out in intensive care units. Results: Of the initial 529 records, 14 were included. Although only two studies were randomized trials, most were small and only one had low risk of bias. In most case reports and in the two retrospective cohort studies, dexmedetomidine appears to be a better option for these symptoms, although differences were not significant in the randomized trials. Discussion: Dexmedetomidine seems to be a promising option for refractory pain and delirium and may contribute to a reduction in opioid administration to control pain. This is the first systematic review of dexmedetomidine in palliative care. Quality evidence is limited, but clinical properties of dexmedetomidine justify the conduction of controlled trials in palliative care.

Trial watch: dexmedetomidine in cancer therapy

Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist that is widely used in intensive and anesthetic care for its sedative and anxiolytic properties. DEX has the capacity to alleviate inflammatory pain while limiting immunosuppressive glucocorticoid stress during major surgery, thus harboring therapeutic benefits for oncological procedures. Recently, the molecular mechanisms of DEX-mediated anticancer effects have been partially deciphered. Together with additional preclinical data, these mechanistic insights support the hypothesis that DEX-induced therapeutic benefits are mediated via the stimulation of adaptive anti-tumor immune responses. Similarly, published clinical trials including ancillary studies described an immunostimulatory role of DEX during the perioperative period of cancer surgery. The impact of DEX on long-term patient survival remains elusive. Nevertheless, DEX-mediated immunostimulation offers an interesting therapeutic option for onco-anesthesia. Our present review comprehensively summarizes data from preclinical and clinical studies as well as from ongoing trials with a distinct focus on the role of DEX in overcoming (tumor microenvironment (TME)-imposed) cancer therapy resistance. The objective of this update is to guide clinicians in their choice toward immunostimulatory onco-anesthetic agents that have the capacity to improve disease outcome.

Effect of Dexmedetomidine on Oxygen and Intrapulmonary Shunt (Qs/Qt) During One-Lung Ventilation in Pediatric Surgery: A Randomized Controlled Trial

Background One-lung ventilation (OLV) is a common ventilation technique used during thoracic surgery. It can cause serious complications in children, and hypoxic pulmonary vasoconstriction (HPV) is a protective mechanism against the resulting hypoxia. Dexmedetomidine does not affect HPV, so we will investigate its impact on the partial pressure of oxygen in arterial blood (PaO2) and pulmonary shunt fraction (Qs/Qt). Methods Children who underwent OLV were divided into two equal groups. The Dex group received 0.4 μg/kg/h of dexmedetomidine intravenously. The placebo group received normal saline. Two blood samples were taken to analyze arterial and central venous blood gasses during four time periods: T1, 10 minutes after anesthesia; T2, 10 minutes after OLV; T3, 60 minutes after OLV; and T4, 20 minutes after the end of OLV. Heart rate, mean arterial pressure (MAP), PaO2, Qs/Qt, and peak inspiratory pressure (PIP) values were recorded at these time points. Results Regarding heart rate, the Dex group remained relatively stable, whereas the placebo group showed a slight increase in T3 and T4. Concerning MAP, the Dex group had a reduction at T1 compared with the placebo group and remained similar for other points. PaO2 decreased with OLV. However, the Dex group consistently maintained higher PaO2 values than the placebo, especially in T3 and T4. Concerning Qs/Qt, the Dex group maintained lower time values than the placebo group at OLV. Regarding PIP, the Dex group had significantly lower T2 and T3 than the placebo group. Conclusion Administration of dexmedetomidine in children with OLV improves PaO2 and reduces pulmonary shunt fraction (Qs/Qt), thereby improving oxygen transport. It reduces the maximum PIP values, thereby reducing pressure-related complications.

Comparison of remimazolam and dexmedetomidine for intraoperative sedation in patients undergoing lower extremity surgery under spinal anesthesia: a randomized clinical trial

BACKGROUND

Dexmedetomidine sedation has advantages, such as low incidence of respiratory depression and prolonged block duration, but also significant disadvantages, such as slow onset, high rate of sedation failure, and a long context-sensitive half-life. Remimazolam provides rapid sedation and recovery, high sedation efficacy and has minimal hemodynamic effects. We hypothesized that patients who received remimazolam would require less rescue midazolam than dexmedetomidine.

METHODS

Patients (n=103) scheduled for surgery under spinal anesthesia were randomized to receive dexmedetomidine (DEX group) or remimazolam (RMZ group) targeting a Modified Observer's Assessment of Alertness/Sedation score of 3 or 4. Rescue midazolam was administered if the patient failed to be sedated after the initial loading dose or despite infusion rate adjustment.

RESULTS

Rescue midazolam administration was significantly higher in the DEX group (0% vs 39.2%; p<0.001). Patients in the RMZ group reached the target sedation level more rapidly. The incidences of bradycardia (0% vs 25.5%; p<0.001) and hypertension (0% vs 21.6%; p<0.001) were higher in the DEX group. Respiratory depression occurred at a higher rate in the RMZ group (21.2% vs 2.0%; p=0.002), but no patients required manual ventilation. Patients in the RMZ group recovered faster, had a shorter PACU stay and higher satisfaction scores. Hypotensive episodes in the PACU were more frequent in the DEX group (1.9% vs 29.4%; p<0.001).

CONCLUSIONS

Remimazolam showed excellent sedation efficacy, minimal hemodynamic effects, and fewer adverse events in the PACU than dexmedetomidine. However, it is important to note that respiratory depression was more frequent with the use of remimazolam.

TRIAL REGISTRATION NUMBER

NCT05447507.

Effectiveness of dexmedetomidine during surgery under general anaesthesia on patient-centred outcomes: a systematic review and Bayesian meta-analysis protocol

INTRODUCTION

Dexmedetomidine is a promising pharmaceutical strategy to minimise opioid use during surgery. Despite its growing use, it is uncertain whether dexmedetomidine can improve patient-centred outcomes such as quality of recovery and pain.

METHODS AND ANALYSIS

We will conduct a systematic review and meta-analysis following the recommendations of the Cochrane Handbook for Systematic Reviews. We will search MEDLINE, Embase, CENTRAL, Web of Science and CINAHL approximately in October 2023. We will include randomised controlled trials evaluating the impact of systemic intraoperative dexmedetomidine on patient-centred outcomes. Patient-centred outcome definition will be based on the consensus definition established by the Standardised Endpoints in Perioperative Medicine initiative (StEP-COMPAC). Our primary outcome will be the quality of recovery after surgery. Our secondary outcomes will be patient well-being, function, health-related quality of life, life impact, multidimensional assessment of postoperative acute pain, chronic pain, persistent postoperative opioid use, opioid-related adverse events, hospital length of stay and adverse events. Two reviewers will independently screen and identify trials and extract data. We will evaluate the risk of bias of trials using the Cochrane Risk of Bias Tool (RoB 2.0). We will synthesise data using a random effects Bayesian model framework, estimating the probability of achieving a benefit and its clinical significance. We will assess statistical heterogeneity with the tau-squared and explore sources of heterogeneity with meta-regression. We have involved patient partners, clinicians, methodologists, and key partner organisations in the development of this protocol, and we plan to continue this collaboration throughout all phases of this systematic review.

ETHICS AND DISSEMINATION

Our systematic review does not require research ethics approval. It will help inform current clinical practice guidelines and guide development of future randomised controlled trials. The results will be disseminated in open-access peer-reviewed journals, presented at conferences and shared among collaborators and networks.

PROSPERO REGISTRATION NUMBER

CRD42023439896.

Efficacy of dexmedetomidine combined with ropivacaine on postoperative analgesia and delirium in elderly patients with total knee arthroplasty

This study aimed to investigate the impact of dexmedetomidine combined with ropivacaine on continuous femoral nerve block (CFNB) in postoperative analgesia and delirium in elderly patients with total knee arthroplasty (TKA). A total of 120 patients who undergone TKA were randomly assigned into group D + R (dexmedetomidine combined with ropivacaine) and group R (only ropivacaine), with 60 cases in each group. The pain scores at rest and exercise at 6 h, 12 h, 24 h, and 48 h postoperatively. The occurrence of delirium on Day 1, Day 2, and Day 3 postoperatively were measured, and the sleep quality was evaluated before surgery, the night of surgery, and 24 h postoperatively to observe the occurrence of postoperative complications. The Visual analogu scale (VAS) of group D + R at 12 h, 24 h, and 48 h postoperatively were lower than those of group R in both rest and exercise states. The incidence of postoperative delirium in group D + R was lower than that in group R on Day 1 and Day 2. Pittsburgh sleep quality index (PSQI) scores in group D + R were lower than those in group R. There was no significant difference in postoperative adverse reactions between the two groups. Dexmedetomidine combined with ropivacaine improves postoperative analgesia and sleep quality, and alleviates the occurrence of postoperative delirium in elderly patients with TKA.

Continuous Serratus - Intercostal Plane Block for Perioperative Analgesia in Upper Abdominal Surgeries: A Prospective Randomized Controlled Study

Objective

Acute pain management after open abdominal surgeries is an essential goal in perioperative management.. Recently, serratus-intercostal plane block (SIPB) was suggested as an analgesic technique for upper abdominal surgeries.

Methods

This prospective, randomized, controlled study included sixty adult patients scheduled for open upper abdominal surgeries. Patients were allocated into two equal groups: SIPB group (S group, n = 30) and control group (the C group, n = 30). In the S group, SIPB was performed in the midaxillary line at the eighth rib level followed by continuous infusion of local anaesthetic for the first postoperative day. In the C group, no block was done. The primary objective of the study was to control postoperative pain on the first postoperative day as assessed by the numerical rating scale (NRS). Secondary outcomes included perioperative hemodynamics, total postoperative analgesic consumption, number of analgesic requests, and incidence of postoperative nausea and vomiting.

Results

The mean postoperative NRS reported in group S was statistically lower than that in group C (2.4±0.7, 3.9±0.31, P < 0.001). The postoperative morphine consumption was lower in the S group than in the C group [(0 (0-4), 3 (1-4), respectively, P < 0.001]. The incidence of PONV was significantly lower in the S group than in the C group (16.7% and 40%, P < 0.045).

Conclusion

SIPB was associated with a better analgesic profile compared with the control group after upper abdominal surgeries. Further studies are recommended to determine block safety in special patient groups, including bariatric and laparoscopic surgeries.

Comparative Effectiveness of Dual- Versus Mono-Sedative Therapy on Opioid Administration, Sedative Administration, and Sedation Level in Mechanically Ventilated, Critically Ill Children

OBJECTIVE

We estimated the effect of early initiation of dual therapy vs monotherapy on drug administration and related outcomes in mechanically ventilated, critically ill children.

METHODS

We used the electronic medical record at a single tertiary medical center to conduct an active comparator, new user cohort study. We included children <18 years of age who were exposed to a sedative or analgesic within 6 hours of intubation. We used stabilized inverse probability of treatment weighting to account for confounding at baseline. We estimated the average effect of initial dual therapy vs monotherapy on outcomes including cumulative opioid, benzodiazepine, and dexmedetomidine dosing; sedation scores; time to double the opioid or benzodiazepine infusion rate; initiation of neuromuscular blockade within the first 7 days of follow-up; time to extubation; and 7-day all-cause in-hospital death.

RESULTS

The cohort included 640 patients. Children receiving dual therapy received 0.03 mg/kg (95% CI, 0.02-0.04) more dexmedetomidine over the first 7 days after initiation of mechanical ventilation than did monotherapy patients. Dual therapy patients had similar sedation scores, time to double therapy, initiation of neuromuscular blockade, and time to extubation as monotherapy patients. Dual therapy patients had a lower incidence of death.

CONCLUSIONS

In this study, initial dual therapy compared with monotherapy does not reduce overall drug administration during mechanical ventilation. The identified effect of dual therapy on mortality deserves further investigation.

Feasibility of the pupillary pain index as a guide for depth of analgesia during opioid-sparing anesthesia with continuous infusion of dexmedetomidine

BACKGROUND

The pupillary dilation reflex (PDR) is an objective indicator of analgesic levels in anesthetized patients. Through measurement of the PDR during increasing tetanic stimulation (10-60 mA), it is possible to obtain the pupillary pain index (PPI), a score that assesses the level of analgesia.

OBJECTIVES

The depth of analgesia during opioid-sparing anesthesia (OSA) with continuous infusion of dexmedetomidine in addition to general anesthesia was assessed.

DESIGN

Observational prospective feasibility pilot study SETTING: This study was performed in the operating rooms of the Spedali Civili University-affiliated hospital of Brescia, Italy.

PATIENTS

Forty-five adults who underwent elective open (5-cm incision) surgery under general anesthesia (78% inhalation anesthesia), from Feb. 18th to Aug. 1st, 2019, were enrolled. Exclusion criteria were as follows: implanted pacemaker or ICD, ophthalmological comorbidities, chronic opioid use, peripheral neuropathy, other adjuvant drugs, epidural analgesia, or locoregional block.

MAIN OUTCOME MEASURES

The first aim was to verify the feasibility of applying a study protocol to evaluate the depth of analgesia during intraoperative dexmedetomidine administration using an instrumental pupillary evaluation. The secondary outcome was to evaluate appropriate analgesia, drug dosage, anesthesia depth, heart rate, blood pressure, transient side effects, postoperative nausea and vomiting (PONV), and pain numerical rating scale (NRS) score.

RESULTS

Thirty out of 50 patients (60%) treated with dexmedetomidine during the study period were included in the DEX group (8 males, age 42 ± 13 years, BMI 45 ± 8), and 15 other patients were included in the N-DEX group (8 males, age 62 ± 13 years, BMI 26 ± 6). Patients who underwent bariatric, abdominal, or plastic surgery were enrolled. At least 3 pupillary evaluations were taken for each patient. PPI ≤ 3 was observed in 97% of patients in the DEX group and 53% in the N-DEX group. Additionally, the DEX group received less than half the remifentanil dose than the N-DEX group (0.13 ± 0.07 vs 0.3 ± 0.11 mcg kg-1 min-1). The average dose of dexmedetomidine administered was 0.17 ± 0.08 mcg kg-1 h-1.

CONCLUSION

The feasibility of applying the protocol was verified. An OSA strategy involving dexmedetomidine may be associated with improved analgesic stability: a randomized controlled trial is necessary to verify this hypothesis.

TRIAL REGISTRATION

Trial.gov registration number: NCT05785273.

Dexmedetomidine as an Adjuvant in Peripheral Nerve Block

Peripheral nerve block technology is important to balanced anesthesia technology. It can effectively reduce opioid usage. It is the key to enhance clinical rehabilitation as an important part of the multimodal analgesia scheme. The emergence of ultrasound technology has accelerated peripheral nerve block technology development. It can directly observe the nerve shape, surrounding tissue, and diffusion path of drugs. It can also reduce the dosage of local anesthetics by improving positioning accuracy while enhancing the block's efficacy. Dexmedetomidine is a highly selective drug α₂-adrenergic receptor agonist. Dexmedetomidine has the characteristics of sedation, analgesia, anti-anxiety, inhibition of sympathetic activity, mild respiratory inhibition, and stable hemodynamics. Numerous studies have revealed that dexmedetomidine in peripheral nerve blocks can shorten the onset time of anesthesia and prolong the time of sensory and motor nerve blocks. Although dexmedetomidine was approved by the European Drug Administration for sedation and analgesia in 2017, it has not yet been approved by the US Food and Drug Administration (FDA). It is used as a non-label drug as an adjuvant. Therefore, the risk-benefit ratio must be evaluated when using these drugs as adjuvants. This review explains the pharmacology and mechanism of dexmedetomidine, the effect of dexmedetomidine on various peripheral nerve block as an adjuvant, and compare it with other types of adjuvants. We summarized and reviewed the application progress of dexmedetomidine as an adjuvant in nerve block and look forward to its future research direction.

The Effect of Epidural Infusion of Dexmedetomidine on Postoperative Analgesia After Thoracotomy: A Randomized Clinical Trial

Background

The unique analgesic properties of dexmedetomidine have led anesthesiologists to use it as an alternative to relieve pain after major surgeries.

Objectives

We aimed to evaluate the effect of continuous injection of thoracic epidural dexmedetomidine on analgesia after thoracotomy.

Methods

In this randomized, double-blind clinical trial, 46 patients (18 to 70 years old) who were candidates for thoracotomy surgery were randomly assigned to receive ropivacaine alone or combined with dexmedetomidine after epidural anesthesia as postoperative epidural anesthesia. The postoperative sedation rate, pain score, and opioid use were assessed within 48 hours after surgery and compared between the 2 groups.

Results

Comparing the mean postoperative sedation scores indicated no difference between the 2 study groups. The pain score assessment showed a lower pain score 6 to 36 hours after surgery in the group receiving concurrent ropivacaine and dexmedetomidine than in the group receiving ropivacaine alone. In the 2 groups receiving ropivacaine with and without dexmedetomidine, the rate of morphine administration after surgery was 43.4% and 65.2%, respectively, indicating no difference. However, the first group received significantly lower doses of morphine after the end of surgery (3.26 ± 0.90 mg vs. 7.04 ± 1.48 mg; P = 0.035).

Conclusions

A combination of ropivacaine and dexmedetomidine as epidural analgesia can lead to lower postoperative pain scores and reduced doses of opioids required.

Role of adjuvants in regional anesthesia: A systematic review

The combination of drugs and routes of administration produces a synergistic effect, and one of the most important components of multimodal analgesic strategies are, therefore, nerve blocks for pain management. The effect of a local anaesthetic can be prolonged by administering an adjuvant. In this systematic review, we included studies on adjuvants associated with local anaesthetics in peripheral nerve blocks published in the last 5 years in order to evaluate their effectiveness. The results were reported according to the PRISMA guidelines. The 79 studies selected using our criteria showed a clear prevalence of dexamethasone (n=24) and dexmedetomidine (n=33) over other adjuvants. Different meta-analyses comparing adjuvants suggest that dexamethasone administered perineurally achieves superior blockade with fewer side effects than dexmedetomidine. Based on the studies reviewed, we found moderate evidence to recommend the use of dexamethasone as an adjuvant to peripheral regional anaesthesia in surgeries that can cause moderate to severe pain.

Dexmedetomidine promotes ferroptotic cell death in gastric cancer via hsa_circ_0008035/miR-302a/E2F7 axis

Dexmedetomidine (DEX), a common anesthetic, has significant effects on the biological features of cancer cells. Although numerous studies have been published on the impact of DEX on the biological characteristics of GC cells, the mechanism remains unknown. This study aimed to explore the effect of DEX on the biological properties of GC cells. DEX suppressed the viability and increased the apoptosis of GC cells in vitro and inhibited tumor growth in vivo. Besides, DEX raised the levels of reactive oxygen species (ROS) and iron, but decreased the levels of glutathione (GSH), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11) in GC cells, which were abolished by Ferrostatin-1 (the inhibitor of ferroptosis) treatment. In addition, the level of circ0008035 and E2F7 were downregulated, but miR-302a level was upregulated in DEX-treated GC cells. Circ0008035 increased the expression of E2F2 by acting as a sponge for miR-302a. Circ0008035 inhibited DEX-induced ferroptotic cell death in GC cells, which was reversed by miR-302a overexpression or E2F7 reduction. Taken together, DEX mediated ferroptotic cell death in GC through regulating the circ0008035/miR-302a/E2F7 axis, suggesting a feasible therapy option for GC.

Efficacy of Dexmedetomidine vs. Remifentanil for Postoperative Analgesia and Opioid-Related Side Effects after Gynecological Laparoscopy: A Prospective Randomized Controlled Trial

Remifentanil is widely used for intraoperative analgesia, but often causes remifentanil-induced hyperalgesia (RIH) and related side effects. Dexmedetomidine, a non-opioid analgesic, has been used as an alternative to remifentanil to prevent RIH. We aimed to investigate the effect of dexmedetomidine on postoperative recovery after gynecological laparoscopy. Ninety-six adult patients undergoing elective gynecological laparoscopy were randomly assigned to the dexmedetomidine or remifentanil groups. The primary outcome was the pain score at 30 min after surgery. The secondary outcomes were intraoperative adverse events (hypotension and bradycardia) and postoperative opioid-related side effects (nausea, vomiting, requirement for rescue analgesics, and shivering). We also performed an ancillary cytokine study to evaluate oxidative stress, one of the causes of RIH. Compared with the remifentanil group, the dexmedetomidine group had lower pain scores at 30 min after surgery (4.0 ± 1.9 vs. 6.1 ± 2.0, mean ± SD, p < 0.001) and lower incidence of intraoperative hypotension and postoperative nausea, vomiting, and shivering. Furthermore, the proportion of patients requiring rescue analgesics was significantly lower in the dexmedetomidine than in the remifentanil group (25% vs. 66.7%, p < 0.001). Cytokine levels did not differ between the groups. Dexmedetomidine showed a better analgesic effect with minimal opioid-related side effects and is considered superior to remifentanil for intraoperative analgesia.

Effects of Peripheral Neural Blocks in Laparoscopic Sleeve Gastrectomy: a Pilot Study on Cognitive Functions in Severe Obese Patients

BACKGROUND

In addition to the analgesic effect, peripheral neural blocks also prevent cognitive impairment and peripheral inflammation induced by surgery. However, it is unknown if there is collateral impact on cognitive improvement after bariatric surgery.

METHODS

In this pilot study, 75 patients with severe obesity for selective laparoscopic sleeve gastrectomy (LSG) were recruited and randomized into three groups (1:1:1) as general anesthesia (GA) group, transverse abdominis plane block (TAPB) group, and quadratus lumborum block (QLB) group. Bilateral TAPB or QLB was performed (0.33% ropivacaine with dexmedetomidine 1 μg/kg) before the standardized general anesthesia. Cognitive test battery was completed before LSG and in 1-month and 3-month follow-up. The levels of peripheral inflammatory cytokines were determined at equivalent time points.

RESULTS

Patients with LSG exhibited massive cognitive improvement in postoperative 3 month without or with TAPB or QLB (P_time < 0.001). Compared to GA, QLB significantly strengthened performance in MoCA (β = 0.56, 95%CI: 0.08, 1.05). IL-6, IL-8, and high-sensitivity CRP significantly verified among three groups. Changes in IL-6 within postoperative 3 months were negatively correlated with MMSE and MoCA, and positively correlated with AVLT-DR for QLB group. Similar correlation was found in the GA group for changes in IL-6 and AVLT-IR.

CONCLUSION

Laparoscopic sleeve gastrectomy ideally improved memory and attention as early as postoperative 1 month. QLB promoted cognitive improvement in MoCA, which was negatively correlated with changes in IL-6. More precise trials are needed to determine the overall effect of peripheral neural block on cognition following bariatric surgery.

Applications of Dexmedetomidine in Palliative and Hospice Care

Although the use of dexmedetomidine is currently approved by the US Food and Drug Administration in the adult population for monitored anesthesia care and sedation during mechanical ventilation, clinical experience suggests the potential application of dexmedetomidine in the palliative care arena. The medication can provide sedation with lower risk of delirium, control or minimize the adverse effects of other medications, and augment analgesia from opioids. We conducted a computerized bibliographic search of the literature regarding dexmedetomidine use for the treatment of pain and provision of sedation during palliative and hospice care in adult and pediatric patients. The objective was to provide a general descriptive account of the physiologic effects of dexmedetomidine and review its potential applications in the field of palliative and hospice care in adult and pediatric patients. The sedative and analgesic effects of dexmedetomidine have been well studied in animal and human models. Published experience from both single case reports and small case series has demonstrated the potential therapeutic applications of dexmedetomidine in palliative and hospice care. In addition to intravenous administration, case reports have demonstrated its successful use by both the intranasal and subcutaneous routes. Although these experiences have suggested its safety and efficacy, larger series and additional clinical experience with prospective comparison to other agents are needed to further define its efficacy and role in palliative and hospice care.

Comparison of Patient-Controlled Caudal Epidural Analgesia and Patient-Controlled Intravenous Analgesia After Perianal Surgery: A Randomized Controlled Trial

INTRODUCTION

This study aimed to compare the efficacy between patient-controlled caudal epidural analgesia (PCCA) and patient-controlled intravenous analgesia (PCIA) after perianal surgery, to provide a feasible solution to postoperative pain.

METHODS

This was a prospective, randomized controlled trial comprising 100 patients who underwent caudal epidural block on perianal surgery at Chengdu Shang Jin Nan Fu Hospital of West China Hospital at Sichuan University between April and August 2020. Patients were randomly divided into the PCCA and PCIA groups. Visual analog scale (VAS) scores were recorded at 2, 4, 6, 24, 48, and 72 h after surgery, and at the first dressing change and first defecation. The lower limb mobility in the post-anesthetic recovery room (PACU) was determined. The analgesic effect, usage amount of patient-controlled analgesia (PCA), usage amount and frequency of remedial analgesic measures, number of individuals who must be catheterized, and incidence of adverse reactions were recorded. Satisfaction of postoperative analgesic effect and convenience of PCA were also assessed.

RESULTS

The patients in the PCCA group had significantly lower VAS scores at 4, 6, 24, 48, 72 h, the first dressing change, and the first defecation compared with the PCIA group. There were more patients receiving postoperative remedial analgesics in the PCIA group than in the PCCA group. The outcome of the number of PCA and catheterization rates did not differ significantly between the groups. There were two cases of sensory numbness below the S3 plane. The major postoperative complications in the PCIA group were pruritus (3/47, 6.4%), nausea, and vomiting (6/47, 12.8%) (one case combined with pruritus). Patients in the PCCA group were more satisfied with the analgesic effect, while those in the PCIA group were more satisfied with the convenience.

CONCLUSION

In the postoperative analgesia program of perianal surgery, PCCA may provide a better analgesic effect without increasing the incidence of complications.

TRIAL REGISTRATION

Chinese Clinical Trial Registry identifier, ChiCTR2000038425, September 2020, retrospectively registered.

Dexmedetomidine Continuous Infusion for Refractory Cancer Pain at End of Life: A Case Report

Refractory cancer-related pain at end-of-life (EoL) is multifaceted and may require utilizing medications with different mechanism of actions beyond opioids. We report the successful use of dexmedetomidine in a 63-year old female with recurrent breast cancer and intractable left arm pain and swelling admitted to University of California, San Diego, Health (UC San Diego Health), palliative care unit. Patient's pain and agitation continued to persist and she declined clinically despite efforts to start methadone, continuous infusion opioids, continuous infusion lidocaine and intravenous chlorpromazine by the palliative care team. On hospital day (HD) 11 patient was started on dexmedetomidine continuous infusion for refractory pain per our protocol at UC San Diego Health. The next day the patient appeared much improved in terms of pain and agitation with grimacing and moaning completely resolved. She was able to have some lucid periods and interacting with her family. With the addition of dexmedetomidine to her pain regiment, the patient was able to peacefully die 5 days later. This case report highlights the clinical utility of demedetomidine in a palliative care unit for refractory pain at EoL.

Dexmededomidine in pediatric unilateral internal inguinal ring ligation

BACKGROUND

Safe and effective analgesia strategy remains one of the priorities for pediatric inguinal hernia treatment.

AIM

To explore safety and efficacy of dexmededomidine monotherapy for postoperative analgesia in children who received laparoscopic unilateral internal inguinal ring ligation.

METHODS

This randomized single-center controlled trial included 390 children (aged 1-3 years, ASA grade I-II), randomly divided into a dexmededomidine group (D group), a dexmededomidine + sufentanil group (DS group), and a sufentanil group (S group). The primary endpoint was percentage of children with the Face, Legs, Activity, Cry, and Consolability (FLACC) score ≤ 3 points 2 h after surgery.

RESULTS

The comparisons of the FLACC scores at 2, 4, 6, 8, 12, and 24 h were not significantly different among the three groups (P > 0.05). The sedative effects in the D group were significantly better than those in the S group (P > 0.05), but not significantly different from those in the DS group. The incidence of nausea and vomiting was significantly lower in the D group than in the S group and DS group (P > 0.05).

CONCLUSION

Analgesic effects of dexmededomidine monotherapy are comparable to those of sufentanil alone or in combination with dexmededomidine for children who underwent laparoscopic unilateral internal inguinal ring ligation, with better sedative effects and a lower incidence of adverse events.

Effects of Dexmedetomidine Administered Through Different Routes on Kidney Tissue in Rats with Spinal Cord Ischaemia–Reperfusion Injury

Background

Ischaemia–reperfusion (IR) injury, which can be encountered during surgical procedures involving the abdominal aorta, is a complex process that affects distant organs, such as the heart, liver, kidney, and lungs, as well as the lower extremities. In this study, we aimed to contribute to the limited literature by investigating the protective effect of dexmedetomidine, which was administered through different routes, on kidney tissue in rats with spinal cord IR injury.

Methods

A total of 30 rats were randomly divided into five groups: control (C group), IR (IR group), IR-intraperitoneal dexmedetomidine (IRIPD group), IR-intrathecal dexmedetomidine (IRITD group), and IR-intravenous dexmedetomidine (IRIVD group). The spinal cord IR model was established. Dexmedetomidine was administered at doses of 100 µg/kg intraperitoneally, 3 µg/kg intrathecally, and 9 µg/kg intravenously. Histopathologic parameters in kidney tissue samples taken at the end of the reperfusion period and biochemical parameters in serum were evaluated.

Results

When examined histopathologically, tubular dilatation was found to be significantly reduced in the IRIVD, IRITD, and IRIPD groups compared with the IR group (p = 0.012, all). Vascular vacuolization and hypertrophy were significantly decreased in the IRIVD, IRITD, and IRIPD groups compared with the IR group (p = 0.006, all). Tubular cell degeneration and necrosis were significantly reduced in the IRIVD, IRITD, and IRIPD groups compared with the IR group (p = 0.008, p = 0.08, and p = 0.030, respectively). Lymphocyte infiltration was significantly decreased in the IRIVD and IRITD groups compared with the IR group (p = 0.006 and p = 0.06, respectively).

Conclusion

It was observed that dexmedetomidine administered by different routes improved the damage caused by IR in kidney histopathology. We think that the renoprotective effects of dexmedetomidine administered intravenously and intrathecally before IR in rats are greater.

Effect of intratracheal dexmedetomidine combined with ropivacaine on postoperative sore throat: a prospective randomised double-blinded controlled trial

Background

The present study aimed to investigate whether intratracheal dexmedetomidine combined with ropivacaine reduces the severity and incidence of postoperative sore throat after tracheal intubation under general anaesthesia.

Methods

Two hundred patients with American Society of Anaesthesiologists physical status I-II who were subjected to general anaesthesia were randomly divided into four groups, namely, Group D, Group R, Group DR and Group S; these groups received intratracheal dexmedetomidine (1 µg/kg), 0.8% ropivacaine (40 mg), dexmedetomidine (1 µg/kg) combined with 0.8% ropivacaine (40 mg) and normal saline before endotracheal intubation, respectively. The primary outcomes were the incidence and grade of sore throat and hoarseness at 2 h and 24 h after surgery. Moreover, the modified Observer's Assessment of Alertness/Sedation Scale results were recorded at each time point. The secondary outcomes were intraoperative haemodynamic fluctuations, intraoperative anaesthetic drug requirements, and adverse reactions during and after surgery. The patients’ vital signs before induction, before superficial anaesthesia, after superficial anaesthesia, before intubation, after intubation, and 1 min after intubation were recorded. The use of anaesthetic drugs and occurrence of adverse effects were also recorded.

Results

The incidence and severity of sore throat were significantly lower in Group DR than in the other three groups 2 h after the operation, but they were only significantly lower in Group DR than in the control group 24 h after the operation. Moreover, compared with Group S and Group D, Group DR exhibited more stable haemodynamics during intubation. The doses of remifentanil and propofol were significantly lower in Group DR than in the other groups.

Conclusion

The combined use of dexmedetomidine and ropivacaine for surface anaesthesia before intubation significantly reduced the incidence and severity of postoperative sore throat. This treatment also decreased anaesthetic drug requirements and intraoperative haemodynamic fluctuations and caused no adverse effects.

Trial registration

This clinical research was registered at the Chinese Clinical Trial Registry (ChiCTR1900022907, Registration date 30/04/2019).

Ropivacaine with Dexmedetomidine or Dexamethasone in a Thoracic Paravertebral Nerve Block Combined with an Erector Spinae Plane Block for Thoracoscopic Lobectomy Analgesia: A Randomized Controlled Trial

Objective

This study aimed to investigate the effect of ropivacaine with dexmedetomidine or dexamethasone in a thoracic paravertebral nerve block (TPVB) combined with an erector spinae plane block (ESPB) for thoracoscopic lobectomy analgesia.

Methods

A total of 97 patients undergoing thoracoscopic lobectomy under general anesthesia were enrolled in this study and randomly divided into three groups, ie, a ropivacaine group (Group R), a ropivacaine + dexmedetomidine group (Group R1), and a ropivacaine + dexamethasone group (Group R2). Ultrasound-guided TPVB combined with an erector spinae plane block was given after anesthesia induction. The following were applied to each group: Group R received 30 mL of 0.5% ropivacaine + 5 mL of a normal saline mixture; Group R1 received 30 mL of 0.5% ropivacaine + 5 mL of a 1 μg/kg dexmedetomidine mixture; Group R2 received 30 mL of 0.5% ropivacaine + 5 mL of an 8 mg dexamethasone mixture. The primary observation index was the time to the first postoperative remedial analgesia. The secondary observation indexes were the intraoperative consumption of propofol and sufentanil, time to waking from anesthesia, time to extubation, postoperative numerical rating scaltpe (NRS) score, postoperative sufentanil consumption, remedial analgesic dosage, and adverse reactions.

Results

When compared with Group R, the time to first postoperative remedial analgesia was longer, the intraoperative and postoperative sufentanil consumption and flurbiprofen axetil remedial analgesic dose were lower, and the time to waking from anesthesia and time to extubation were shorter in groups R1 and R2 (P < 0.05). The NRS scores at 1, 6, 12, and 24 h postoperatively in groups R1 and R2 were lower than in Group R at the same time points (P < 0.05).

Conclusion

Ropivacaine with dexmedetomidine or dexamethasone in TPVB combined with ESPB could prolong the time to first postoperative remedial analgesia, reduce perioperative sufentanil and postoperative remedial analgesic drug consumption, and decrease the postoperative NRS score in patients undergoing thoracoscopic lobectomy.

Meldonium Ameliorates Hypoxia-Induced Lung Injury and Oxidative Stress by Regulating Platelet-Type Phosphofructokinase-Mediated Glycolysis

Hypoxic environments at high altitudes influence the long-term non-altitude health of residents, by inducing changes in metabolism and the mitochondria, severe lung injury, and endangering life. This study was aimed to determine whether meldonium can ameliorate hypoxia-induced lung injury and investigate its possible molecular mechanisms. We used Swiss mice and exposed type Ⅱ alveolar epithelial cell to hypobaric hypoxic conditions to induce lung injury and found that meldonium has significant preventive effect, which was associated with the regulation of glycolysis. We found using human proteome microarrays assay, molecular docking, immunofluorescence and pull-down assay that the target protein of meldonium is a platelet-type phosphofructokinase (PFKP), which is a rate-limiting enzyme of glycolysis. Also, meldonium promotes the transfer of nuclear factor erythroid 2-related factor 2 (Nrf2) from the cytoplasm to the nucleus, which mitigates oxidative stress and mitochondrial damage under hypoxic condition. Mechanistically, meldonium ameliorates lung injury by targeting PFKP to regulate glycolysis, which promotes Nrf2 translocation from the cytoplasm to the nucleus to alleviate oxidative stress and mitochondrial damage under hypoxic condition. Our study provides a novel potential prevention and treatment strategy against hypoxia-induced lung injury.

Dexmedetomidine combined with ropivacaine for erector spinae plane block after posterior lumbar spine surgery: a randomized controlled trial

Purpose

Due to lumbar spinal surgery is frequently accompanied with moderate-to-severe postoperative pain, it is necessary to find an effective postoperative analgesia for patients with this surgery. This study aimed to observe the analgesic effect of dexmedetomidine combined with ropivacaine erector spinae plane block (ESPB) used in posterior lumbar spine surgery.

Methods

In this clinical trial, patients undergoing posterior lumbar spine surgery were recruited and randomly divided into two groups: intervention and control. The intervention group (Group E) received 0.375% ropivacaine with 1 µg/kg dexmedetomidine in a total of 20 ml for ESPB; the control group (Group C) received 20 ml ropivacaine 0.375% for ESPB. US-guided ESPB was performed preoperatively in all patients. Demographics, anesthesia time, surgery time, and ASA grade from the participants were recorded at baseline. The primary clinical outcome measures were 2-, 4-, 8-, 12-, 24-and 48-h visual analog scale (VAS) pain scores after surgery at rest and movement state. Other end points included opioid consumption, number of PCIA presses, flurbiprofen-axetil consumption, quality of recovery and pain management after surgery.

Results

One hundred twenty patients were enrolled in the study (mean [SD] ages: Group E, 54.77 [8.61] years old; Group C,56.40 [7.87] years old; P = 0.280). The mean anesthesia time was 152.55 (15.37) min in Group E and 152.60 (16.47) min in Group C (P = 0.986). Additionally, the surgery time was 141.70 (15.71) min in Group E compared to 141.48 (17.13) min in Group C (P = 0.943). In addition, we found that the VAS pain scores in the resting state during the postoperative period at 8–48 h were lower in Group E than in Group C. However, the VAS pain scores in the active state were lower in Group E at 12–48 h (P < 0.05). More importantly, the consumption of opioids and flurbiprofen-axetil after surgery was also lower in Group E (P < 0.05). Subsequently, we administered questionnaires on the quality of recovery and pain management after surgery that were positively correlated with the postoperative analgesic effect. It was worth affirming that the QoR-15 scores and APS-POQ-R questionnaire results were different between the two groups, further confirming that the combination of drugs not only could obtain an ideal analgesic effect but also had no obvious adverse reactions (P < 0.05).

Conclusions

All the findings suggested that dexmedetomidine could significantly relieve postoperative pain and reduce the consumption of opioids in patients undergoing posterior lumbar spine surgery without obvious adverse reactions as a local anesthetic adjuvant. Further studies with larger sample sizes and different drug dosages may be useful in understanding the potential clinical benefits of dexmedetomidine.

Can Acute Postoperative Pain Management After Tumour Resection Surgery Modulate Risk of Later Recurrence or Metastasis?

Background

Cancer is a leading cause of mortality worldwide, but death is rarely from the primary tumour: Rather it is multi-organ dysfunction from metastatic disease that is responsible for up to 90% of cancer-related deaths. Surgical resection of the primary tumour is indicated in 70% of cases. The perioperative stress response, tissue hypoxia at the site of surgery, and acute pain contribute to immunosuppression and neo-angiogenesis, potentially promoting tumour survival, proliferation, and metastasis. Poorly controlled acute postoperative pain decreases Natural Killer (NK) immune cell activity, which could potentially facilitate circulating tumour cells from evading immune detection. This consequently promotes tumour growth and distal metastasis.

Methods

We conducted a comprehensive literature search for links between acute pain and cancer outcomes using multiple online databases. Relevant articles from January 1st, 2010 to September 1st, 2021 were analysed and appraised on whether postoperative pain control can modulate the risk of recurrence, metastasis, and overall cancer survival.

Results

Although experimental and retrospective clinical data suggest a plausible role for regional anaesthesia in cancer outcome modulation, this has not been supported by the single, largest prospective trial to date concerning breast cancer. While there are mixed results on anaesthesiology drug-related interventions, the most plausible data relates to total intravenous anaesthesia with propofol, and to systemic administration of lidocaine.

Conclusion

The hypothesis that anaesthetic and analgesic technique during cancer surgery could influence risk of subsequent recurrence or metastasis has been prevalent for >15 years. The first, large-scale definitive trial among women with breast cancer found robust equivalent findings between volatile anaesthesia with opioid analgesia and regional anaesthesia. Therefore, while regional anaesthesia during tumour resection does not seem to have any effect on cancer outcomes, it remains plausible that other anaesthetic techniques (e.g. total intravenous anaesthesia and systemic lidocaine infusion) might influence oncologic outcome in other major tumour resection surgery (e.g. colorectal and lung). Therefore, another large trial is needed to definitively answer these specific research questions. Until such evidence is available, perioperative analgesia for cancer surgery of curative intent should be based on patient co-morbidity and non-cancer endpoints, such as optimising analgesia and minimising postoperative complications.

Central nervous system monoaminergic activity in hip osteoarthritis patients with disabling pain: associations with pain severity and central sensitization

In patients with osteoarthritis undergoing total hip arthroplasty, higher cerebrospinal fluid concentrations of serotonin and dopamine metabolites are associated with increased pain severity and central sensitization.

Introduction:

Objectives:

Methods:

Results:

Conclusions:

The Role of Serratus Anterior Plane Block During in Video-Assisted Thoracoscopic Surgery

Although thoracoscopy has characteristics such as a small surgical incision and low stress response, post-surgical pain after a thoracoscopic operation is no less than that after a thoracotomy. Moreover, poor post-surgical pain management is likely to cause an increased incidence of postoperative pulmonary complications (PPCs) and chronic post-surgical pain. The serratus anterior plane block (SAPB) is a regional anesthesia method whereby local anesthetics (LAs) are injected into the serratus anterior space to block the lateral cutaneous branch of the intercostal nerve, long thoracic nerve, and dorsal thoracic nerve. The block range of the SAPB covers the incisions of video-assisted thoracoscopic surgery (VATS) and the site of the chest tube, which are often located in the antero-lateral chest wall. Therefore, the SAPB can achieve effective analgesia in VATS. For example, 0.125% to 0.25% levobupivacaine (20-25 ml) is widely used for thoracic surgery, which can achieve effective analgesia and avoid adverse reactions. Moreover, it has advantages compared with thoracic segmental epidural block (TEA) and thoracic paravertebral block (TPVB), such as simple operation, increased safety, fewer complications, and hemodynamic stability. In addition, adequate analgesia is helpful for pulmonary function recovery and reduces the incidence of PPCs. This article introduces the anatomical mechanism of the SAPB, diverse operation approaches, how to choose drugs and adjuvants, and the resulting impacted area range. It summarizes the advantages and disadvantages of the SAPB compared with other analgesic methods and posits that the SAPB is beneficial to the recovery of postoperative lung function, which provides more options for postoperative analgesia after VATS.

Ambulatory Anesthesia for a Case of Idiopathic Bronchiolitis Obliterans

Bronchiolitis obliterans is rarely described in the nonlung transplant anesthesia literature. This case report describes a 27-year-old female patient with idiopathic bronchiolitis obliterans and dental anxiety who safely received intravenous deep sedation using diphenhydramine, dexmedetomidine, and ketamine in an ambulatory community dental clinic. This report outlines the anesthetic plan developed following a thorough preoperative assessment and review of the key anesthetic considerations of idiopathic bronchiolitis obliterans (eg, potential respiratory complications and appropriateness for the ambulatory dental environment) and discusses the careful anesthetic management of this patient using deep sedation to facilitate comprehensive restorative dentistry.

Efficacy of perineural versus intravenous dexmedetomidine as a peripheral nerve block adjunct: a systematic review

BACKGROUND

Dexmedetomidine is an effective local anesthetic adjunct for peripheral nerve blocks. The intravenous route for administering dexmedetomidine has been suggested to be equally effective to the perineural route; but comparative evidence is conflicting.

OBJECTIVES

This evidence-based review evaluated trials comparing the effects of intravenous to perineural dexmedetomidine on peripheral nerve block characteristics in adult surgical patients. Our primary aim was to evaluate the durations of sensory and motor blockade. Duration of analgesia, onset times of sensory and motor blockade, analgesic consumption, rest pain, and dexmedetomidine-related adverse events were evaluated as secondary outcomes.

EVIDENCE REVIEW

We sought randomized trials comparing the effects of intravenous to perineural dexmedetomidine on peripheral nerve block characteristics. The Cochrane Risk of Bias tool and the Grades of Recommendation, Assessment, Development, and Evaluation criteria was used to evaluate the quality of evidence for when an outcome was reported by at least three studies.

RESULTS

Ten studies compared intravenous and perineural dexmedetomidine in the setting of upper extremity blocks (seven), lower extremity blocks (two), and truncal block (one). The doses of dexmedetomidine supplementing long-acting local anesthetics varied between a predetermined dose (50 μg) and a weight-based dose (0.5 μg/kg-1.0 μg/kg). Clinical diversity precluded quantitative pooling; and evidence is presented as a systematic review. Compared with the intravenous route, moderate quality evidence found that perineural dexmedetomidine prolonged the duration of sensory blockade in four of six trials and motor blockade in five of seven trials. Perineural dexmedetomidine also hastened the onset of sensory and motor blockade in three of six trials. No differences were reported for the remaining outcomes; and intravenous dexmedetomidine was not superior for any outcome in any of the trials.

CONCLUSIONS

Moderate quality evidence appears to suggest that intravenous dexmedetomidine is an inferior peripheral nerve block adjunct compared with perineural dexmedetomidine. Perineural dexmedetomidine is associated with longer durations and faster onset of sensory and motor blockade.

Dexmedetomidine for hyperactive delirium at the end of life: An open-label single arm pilot study with dose escalation in adult patients admitted to an inpatient palliative care unit

BACKGROUND

Terminal delirium, specifically the hyperactive delirium subtype at the end of life, is common in palliative care patients. Standard care often involves sedation to alleviate distress. The alpha₂-adrenoreceptor agonist dexmedetomidine may have promise in terminal delirium, due to its properties of decreasing delirium and permitting rousable sedation.

AIM

This study aimed to describe the effect of dexmedetomidine on delirium and sedation, when delivered via continuous subcutaneous infusion (CSCI) in patients with terminal delirium.

DESIGN

The trial was prospectively registered in the ANZCTR database (ACTRN12618000658213) and conducted in accordance with CONSORT (pilot study extension). Twenty-two adult patients were treated with a CSCI of dexmedetomidine with a two-tier dose schedule, low and high dose. Delirium severity was measured by the Memorial Delirium Assessment Scale (MDAS, target <13), and sedation by the Richmond Agitation-Sedation Scale, Palliative Version (RASS-PAL, target -1 to -3).

RESULTS

All patients had a response to dexmedetomidine as measured by decrease in MDAS after initiation; 59% required escalation to high dose to maintain control of delirium. All responses to high dose were sustained. RASS-PAL scores showed significant variability, however mean scores remained within target range on both doses, and the majority of patients were rousable. Fifty percent of patients treated crossed over to standard care; no patients who crossed over were experiencing moderate-severe delirium. Predominant reason for crossover was family request for deeper sedation.

CONCLUSION

Dexmedetomidine shows potential for the management of terminal delirium with improved interactivity. Further research is needed to determine efficacy compared to current standard care.

Dexmedetomidine with sufentanil in intravenous patient-controlled analgesia for relief from postoperative pain, inflammation and delirium after esophageal cancer surgery

BACKGROUND AND AIMS

Postoperative pain can cause serious adverse reactions that severely affect postoperative outcome. The present study evaluated the effect of dexmedetomidine (DEX) added to sufentanil in intravenous patient-controlled analgesia (PCA) on the relief of pain and inflammatory responses during postoperative recovery of patients undergoing a combined thoracoscopic-laparoscopic esophagectomy (TLE).

METHODS

Sixty patients undergoing TLE were randomly allocated to receive 1 μg/ml of sufentanil alone (Group S) or 1 μg/ml of sufentanil plus 2.5 μg/ml of DEX (Group D) for postoperative intravenous (IV) PCA. Postoperative pain relief, cumulative PCA requirements, inflammatory marker levels, delirium and recovery were assessed.

RESULTS

A joint DEX and sufentanil regimen significantly reduced the area under the curve of numerical rating scores for pain at rest (NRSR) and coughing (NRSC) at 1-48 h postoperatively (P = 0.000) that were associated with lower PCA-delivered cumulative sufentanil consumption and less PCA frequency until 48 h postoperatively (P < 0.05 and P < 0.0001, respectively). The simultaneous administration of DEX and sufentanil significantly reduced plasma IL-6 and TNF-α concentrations and increased IL-10 level (P < 0.0001, P = 0.0003 and P = 0.0345, respectively), accompanied by better postoperative delirium categories and health statuses of patients (P = 0.024 and P < 0.05, respectively). There was no hypotension, bradycardia, respiratory depression or oversedation in Group D.

CONCLUSION

Patients receiving DEX in addition to IV PCA sufentanil for TLE exhibited better postoperative analgesia, fewer inflammatory responses and lower postoperative delirium categories and better health statuses.

Feasibility of Intranasal Dexmedetomidine in Treatment of Postoperative Restlessness, Agitation, and Pain in Geriatric Orthopedic Patients

Objective

The aim of this study was to report preliminary data on the use of intranasal dexmedetomidine to treat postoperative restlessness, agitation, and pain in 23 patients aged > 70 years and undergoing orthopedic surgery.

Background

Postoperative agitation and delirium are common among older adult patients undergoing orthopedic surgery. Most preparations used to treat agitation and delirium carry a risk for adverse events such as respiratory failure. Moreover, mere opioid therapy may be insufficient in treatment of pain. Dexmedetomidine, an α2-adrenoreceptor agonist with sedative and analgesic properties, has been shown to reduce opioid requirement and reduce postoperative delirium in older adults.

Methods

We studied the use of post-operative intranasal dexmedetomidine in a retrospective study cohort of geriatric patients undergoing orthopedic surgery. Primary outcomes included alterations in heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peripheral oxygen saturation (SpO2), Modified Richmond Agitation and Sedation Score (mRASS), and opioid consumption following dexmedetomidine administration.

Results

We identified 23 patients with a mean (SD) age of 79.9 (7.5) years who received dexmedetomidine 100 µg intranasally postoperatively. After dexmedetomidine administration, HR decreased by 10.4 (3.7) beats/min (95% CI 2.9–17.8; p = 0.004) and MAP by 16.2 (4.4) mmHg (95% CI 7.3–25.1; p < 0.001). HR decrease was significant at 2 h and MAP decrease at 1, 2, and 3 h following dexmedetomidine administration. Dexmedetomidine administration was associated with significant reductions in opioid consumption (p < 0.001) and mRASS score (p < 0.001). SpO₂ and RR remained unchanged.

Conclusions

These preliminary findings suggest that intranasal dexmedetomidine reduces opioid consumption without causing respiratory depression and may be used to treat postoperative restlessness, agitation, and pain in geriatric patients. However, hemodynamic effects of dexmedetomidine may require close observation for 3 hours following administration in older adult patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40266-021-00846-6.

HTX-011 (bupivacaine and meloxicam) for the prevention of postoperative pain - clinical considerations

HTX-011 is an extended-release, dual-acting local anesthetic consisting of bupivacaine (sodium-channel blocker) and low-dose meloxicam (non-steroidal anti-inflammatory drug [NSAID]) applied needle-free during surgery. Introducing low-dose meloxicam addresses the limited efficacy of liposomal bupivacaine in acidic inflamed tissues and allows enhanced analgesic effects over three days. It has great promise to be an extremely effective postoperative pain regimen and produce an opioid-free surgical recovery, as it has consistently significantly reduced pain scores and opioid consumption through 72 h. This manuscript provides an updated, concise narrative review of the pharmacology, clinical efficacy, safety and tolerability of this drug and its applications to prevent postoperative pain.

Dexmedetomidine as an adjunct to local anesthetics in nerve block relieved pain more effectively after TKA: a meta-analysis of randomized controlled trials

Background

Dexmedetomidine has shown potential in pain control in patients undergoing total knee arthroplasty (TKA). However, the combination of nerve block and dexmedetomidine may be a preferred alternative for postoperative analgesia after TKA. The aim of this study was to perform a meta-analysis on existing randomized controlled trials (RCTs) to determine the efficacy and safety of dexmedetomidine as an adjunct to local anesthetics in nerve block after TKA.

Methods

A literature survey was conducted in the databases of PubMed, Embase, Cochrane Library, Web of science, and ScienceDirect for the RCTs completed before February 1st, 2020 that met pre-specified inclusion criteria. The primary outcomes included the pain scores, duration of analgesia, opioid consumption within 24 h postoperatively, and the level of patient satisfaction. The secondary outcomes included the motor strength, degree of sedation, postoperative nausea and vomiting, and other related complications. The methodological quality was assessed by the Cochrane risk of bias tool.

Results

The initial literature search yielded 143 studies, out of which seven studies met the inclusion criteria. The pooled data indicated that dexmedetomidine combined with local anesthetics in nerve block in TKA decreased the postoperative pain scores at rest as well as at motion (SMD = − 1.01 [95% CI − 1.29 to − 0.72], p < 0.01; SMD = − 1.01 [− 1.25 to − 0.77], p < 0.01) respectively, decreased the total opioid consumption within 24 h (SMD = − 0.63 [− 0.86 to − 0.40], p < 0.01), prolonged the duration of analgesia (SMD = 0.90 [0.64 to 1.17], p < 0.01), improved motor strength (SMD = 0.23 [0.01 to 0.45], p = 0.04), improved the degree of sedation (SMD = 0.94 [0.70 to 1.18], p < 0.01), and increased the level of patient satisfaction (SMD = 0.88 [0.60 to 1.17], p < 0.01) without increasing nausea and vomiting (RD = − 0.05 [− 0.11 to 0.01], p = 0.14), as well as other complications (RD = − 0.01 [− 0.08 to 0.07], p = 0.89), compared with local anesthetics alone.

Conclusions

It is effective and safe for dexmedetomidine as an adjunct to local anesthetics in nerve block in TKA to relieve postoperative pain, decrease total opioid consumption, prolong analgesic duration, and increase patient satisfaction without increasing related complications. Based on the quality of evidence, this meta-analysis recommends that dexmedetomidine can be used in a regular treatment regimen and as an adjunct addition to local anesthetics in nerve block for patients undergoing TKA.

Registration

This meta-analysis was prospectively registered on PROSPERO (International prospective register of systematic reviews) and the registering number was CRD42020169171.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02105-7.

Review of nonopioid multimodal analgesia for surgical and trauma patients

Purpose

Pain is a frequent finding in surgical and trauma patients, and effective pain control remains a common challenge in the hospital setting. Opioids have traditionally been the foundation of pain management; however, these agents are associated with various adverse effects and risks of dependence and diversion.

Summary

In response to the rising national opioid epidemic and the various risks associated with opioid use, multimodal pain management through use of nonopioid analgesics such as acetaminophen, nonsteroidal anti-inflammatory drugs, α 2 agonists, N-methyl-d-aspartate (NMDA) receptor antagonists, skeletal muscle relaxants, sodium channel blockers, and local anesthetics has gained popularity recently. Multimodal analgesia has synergistic therapeutic effects and can decrease adverse effects by enabling use of lower doses of each agent in the multimodal regimen. This review discusses properties of the various nonopioid analgesics and encourages pharmacists to play an active role in the selection, initiation, and dose-titration of multimodal analgesia. The choice of nonopioid agents should be based on patient comorbidities, hemodynamic stability, and the agents’ respective adverse effect profiles. A multidisciplinary plan for management of pain should be formulated during transitions of care and is an area of opportunity for pharmacists to improve patient care.

Conclusion

Multimodal analgesia effectively treats pain while decreasing adverse effects. There is mounting evidence to support use of this strategy to decrease opioid use. As medication experts, pharmacists can play a key role in the selection, initiation, and dose-titration of analgesic agents based on patient-specific factors.

Neuroprotective Effects of Dexmedetomidine Preconditioning on Oxygen-glucose Deprivation-reoxygenation Injury in PC12 Cells via Regulation of Ca2+-STIM1/Orai1 Signaling

Dexmedetomidine (DEX), a potent and highly selective agonist for α₂-adrenergic receptors (α₂AR), exerts neuroprotective effects by reducing apoptosis through decreased neuronal Ca²⁺ influx. However, the exact action mechanism of DEX and its effects on oxygen-glucose deprivation-reoxygenation (OGD/R) injury in vitro are unknown. We demonstrate that DEX pretreatment reduced OGD/R injury in PC12 cells, as evidenced by decreased oxidative stress, autophagy, and neuronal apoptosis. Specifically, DEX pretreatment decreased the expression levels of stromal interaction molecule 1 (STIM1) and calcium release-activated calcium channel protein 1 (Orai1), and reduced the concentration of intracellular calcium pools. In addition, variations in cytosolic calcium concentration altered apoptosis rate of PC12 cells after exposure to hypoxic conditions, which were modulated through STIM1/Orai1 signaling. Moreover, DEX pretreatment decreased the expression levels of Beclin-1 and microtubule-associated protein 1A/1B-light chain 3 (LC3), hallmark markers of autophagy, and the formation of autophagosomes. In conclusion, these results suggested that DEX exerts neuroprotective effects against oxidative stress, autophagy, and neuronal apoptosis after OGD/R injury via modulation of Ca²⁺-STIM1/Orai1 signaling. Our results offer insights into the molecular mechanisms of DEX in protecting against neuronal ischemia-reperfusion injury.

Effect of Intraoperative Dexmedetomidine on Postoperative Pain and Pulmonary Function Following Video-assisted Thoracoscopic Surgery

Context:

Acute postoperative pain following video-assisted thoracoscopic surgery (VATS) needs considerable attention, if untreated leads to chronic pain and postoperative lung dysfunction. Dexmedetomidine, α₂ adrenoceptor agonist has shown promising results of opioid-sparing effects.

Aims:

The objectives of this study are to investigate the effect of dexmedetomidine on postoperative analgesia and pulmonary mechanics in patients undergoing VATS.

Settings and Design:

This is a randomized controlled trial.

Subjects and Methods:

We conducted a prospective, randomized, double-blind study on lung cancer patients undergoing VATS. Each patient received either dexmedetomidine or comparable volume of normal saline during the intraoperative period. In the recovery unit, postoperative visual analog scale (VAS) score, rescue analgesic requirements, arterial blood gas values, and pulmonary function tests were recorded.

Statistical Analysis Used:

Data are analyzed using unpaired t-test, Mann–Whitney U-test, and Fischer's exact test. P < 0.05 was considered statistically significant.

Results:

VAS scores were significantly lower (P < 0.05) in the dexmedetomidine group at rest, on coughing and on mobilization from supine to sitting position. The partial pressure of arterial oxygen measured in postanesthesia care unit was significantly higher in the dexmedetomidine group (88 ± 8.2 vs 78 ± 9.1 mmHg). Forced expiratory volume in 1 was significantly greater in the dexmedetomidine group compared to the control group on the first 2 postoperative days (P < 0.05). The length of hospital stay was significantly reduced by dexmedetomidine.

Conclusions:

Intraoperative dexmedetomidine administration improves the quality of analgesia and postoperative lung function in patients undergoing VATS.

Dexmedetomidine in cancer surgeries: Present status and consequences with its use

Dexmedetomidine is a centrally acting α2 adrenoreceptor agonist used in perioperative medicine due to its sedative, analgesic and sympatholytic properties. Recently animal data has pointed towards potential role of dexmedetomidine in promoting cancer recurrence and metastasis when used perioperatively especially after breast surgeries. This is because of presence of α2 adrenoreceptors in breast cancer tissue. We reviewed existing literature in which dexmedetomidine was used in cancer surgeries and investigated its role in recurrence and metastasis.

Dexmedetomidine for reduction of atrial fibrillation and delirium after cardiac surgery (DECADE): a randomised placebo-controlled trial

BACKGROUND

Atrial fibrillation and delirium are common consequences of cardiac surgery. Dexmedetomidine has unique properties as sedative agent and might reduce the risk of each complication. This study coprimarily aimed to establish whether dexmedetomidine reduces the incidence of new-onset atrial fibrillation and the incidence of delirium.

METHODS

A randomised, placebo-controlled trial was done at six academic hospitals in the USA. Patients who had had cardiac surgery with cardiopulmonary bypass were enrolled. Patients were randomly assigned 1:1, stratified by site, to dexmedetomidine or normal saline placebo. Randomisation was computer generated with random permuted block size 2 and 4, and allocation was concealed by a web-based system. Patients, caregivers, and evaluators were all masked to treatment. The study drug was prepared by the pharmacy or an otherwise uninvolved research associate so that investigators and clinicians were fully masked to allocation. Participants were given either dexmedetomidine infusion or saline placebo started before the surgical incision at a rate of 0·1 μg/kg per h then increased to 0·2 μg/kg per h at the end of bypass, and postoperatively increased to 0·4 μg/kg per h, which was maintained until 24 h. The coprimary outcomes were atrial fibrillation and delirium occurring between intensive care unit admission and the earlier of postoperative day 5 or hospital discharge. All analyses were intention-to-treat. The trial is registered with ClinicalTrials.gov, NCT02004613 and is closed.

FINDINGS

798 patients of 3357 screened were enrolled from April 17, 2013, to Dec 6, 2018. The trial was stopped per protocol after the last designated interim analysis. Among 798 patients randomly assigned, 794 were analysed, with 400 assigned to dexmedetomidine and 398 assigned to placebo. The incidence of atrial fibrillation was 121 (30%) in 397 patients given dexmedetomidine and 134 (34%) in 395 patients given placebo, a difference that was not significant: relative risk 0·90 (97·8% CI 0·72, 1·15; p=0·34). The incidence of delirium was non-significantly increased from 12% in patients given placebo to 17% in those given dexmedetomidine: 1·48 (97·8% CI 0·99-2·23). Safety outcomes were clinically important bradycardia (requiring treatment) and hypotension, myocardial infarction, stroke, surgical site infection, pulmonary embolism, deep venous thrombosis, and death. 21 (5%) of 394 patients given dexmedetomidine and 8 (2%) of 396 patients given placebo, had a serious adverse event as determined by clinicians. 1 (<1%) of 391 patients given dexmedetomidine and 1 (<1%) of 387 patients given placebo died.

INTERPRETATION

Dexmedetomidine infusion, initiated at anaesthetic induction and continued for 24 h, did not decrease postoperative atrial arrhythmias or delirium in patients recovering from cardiac surgery. Dexmedetomidine should not be infused to reduce atrial fibrillation or delirium in patients having cardiac surgery.

FUNDING

Hospira Pharmaceuticals.

Dexmedetomidine pretreatment attenuates myocardial ischemia reperfusion induced acute kidney injury and endoplasmic reticulum stress in human and rat

BACKGROUND

Patients undergoing cardiopulmonary bypass (CPB) often develop acute kidney injury (AKI) caused by myocardial ischemia reperfusion (MI/R), and this renal injury can be resolved notably by dexmedetomidine. Endoplasmic reticulum (ER) stress was reported to get involved in organ injury including AKI.

OBJECTIVES

The current study aimed to address the correlation between MI/R induced AKI with ER stress and to assess the effects of dexmedetomidine pretreatment on AKI protection.

METHOD

Patients selected for heart valve replacement surgery were randomly assigned to NS group (pre-anesthesia with 0.9% NaCl) and DEX group (pre-anesthesia with dexmedetomidine). Rat MI/R model was induced by occluding coronary artery for 30 min followed by 48-hour reperfusion. Rats were randomized into Sham (0.9% NaCl), I/R (MI/R + 0.9% NaCl) and I/R + DEX (MI/R + dexmedetomidine). Organ function and ER stress condition were evaluated by blood chemistry, pathology, and molecular test.

RESULTS

Clinical data indicated dexmedetomidine pretreatment attenuated AKI and oxidative stress as well as postischemic myocardial injury in patients. Accordingly animal results suggested dexmedetomidine reduced cellular injury and improved postischemic myocardial and renal function. Dexmedetomidine also reduced myocardial and renal cells apoptosis and down-regulated ER stress.

CONCLUSIONS

These results suggested that dexmedetomidine pretreatment attenuates MI/R injury-induced AKI by relieving the ER stress.