Dexmedetomidine for prevention of delirium in elderly patients after non-cardiac surgery: a randomised, double-blind, placebo-controlled trial

Dexmedetomidine-mediated improvement of perioperative neurocognitive disorders by miR-184-3p-mediated NLRP3

BACKGROUND

Perioperative neurocognitive disorders (PND) is a neurological complication in the perioperative period, which may lead to severe poor prognosis. Dexmedetomidine (Dex) is a commonly used sedative in the perioperative period. However, the effect of intraoperative anesthetic Dex on PND remains complicated and confusing.

METHODS

PND model was established using aged male mice, treated with Dex, and subjected to behavioral tests. The effect of Dex on pyroptosis was assessed by western blot, enzyme-linked immunosorbent assay and immunofluorescence. In addition, the miRNA expression profile of PND mice was identified by small RNA sequencing and performed PCR to detect miRNAs. Finally, the effect of miRNA on mice neuron pyroptosis was verified in vitro.

RESULTS

We found postoperative cognitive was declined in PND mice compared with control group, while preoperative injection of Dex improved short-term working memory and anxious exploration behavior, alleviated the cognitive impairment. Intriguingly, Dex ameliorated hippocampal inflammation and neuron pyroptosis in PND mice as evidenced by the reduced GSDMD, NLRP3, IL-1β and IL-18. The miRNA expression profile of PND mice hippocampus was disordered, including 5 miRNAs up-regulated and 17 miRNAs down-regulated, compared to the sham group. Dysregulated miRNAs were mainly enriched in biological functions related to neuronal development and signaling pathways related to pyroptosis. MiR-184-3p was the key miRNA, overexpression of miR-184-3p blocked the inhibitory effect of Dex on neuron pyroptosis, which was manifested as increased expression of GSDMD and NLRP3, increased inflammatory factors IL-1β and IL-18.

CONCLUSIONS

This study revealed that miR-184-3p may mediate NLRP3 to prevent the alleviating effect of Dex on PND, which provides a new potential way to improve the therapeutic intervention of PND.

Characteristics associated with effectiveness in postoperative delirium research: a systematic review of randomised controlled trials with meta-regression and meta-analysis

BACKGROUND

Postoperative delirium remains prevalent despite extensive research through randomised trials aimed at reducing its incidence. Understanding trial characteristics associated with interventions' effectiveness facilitates data interpretation.

METHODS

Trial characteristics were extracted from eligible trials identified through two systematic literature searches. Multivariable meta-regression was used to investigate trial characteristics associated with effectiveness estimated using odds ratios. Meta-analysis was used to investigate pooled effectiveness.

RESULTS

We identified 201 eligible trials. Compared with China, trials from the USA/Canada (ratio of odds ratio, 1.89; 95% confidence interval, 1.45-2.45) and Europe/Australia/New Zealand (1.67; 1.29-2.18) had an 89% and 67% higher odds ratio, respectively, suggesting reduced effectiveness. The effectiveness was enhanced when the incidence of postoperative delirium increased (0.85; 0.79-0.92, per 10% increase). Trials with concerns related to deviations from intended interventions reported increased effectiveness compared with those at low risk (0.69; 0.53-0.90). Compared with usual care, certain interventions appeared to have reduced the incidence of postoperative delirium in low-risk trials with low-to-moderate certainty of evidence. However, these findings should be considered inconclusive because of challenges in grouping heterogeneous interventions, the limited number of eligible trials, the prevalence of small-scale studies, and potential publication bias.

CONCLUSIONS

The effectiveness of postoperative delirium trials varied based on the region of trial origin, the incidence of delirium, and the risk of bias. The limitations caution against drawing definitive conclusions from different bodies of evidence. These findings highlight the imperative need to improve the quality of research on a global scale.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42023413984).

The Effect of Low-Dose Dexmedetomidine on Perioperative Neurocognitive Dysfunction in Elderly Patients Undergoing Endoscopic Retrograde Cholangiopancreatography (ERCP): A Randomized, Controlled, Double-Blind Trial

Objective

This study investigates the effect of low-dose dexmedetomidine infusion on perioperative neurocognitive function in elderly patients undergoing endoscopic retrograde cholangiopancreatography (ERCP).

Patients and Methods

This double-blind trial enrolled 80 elderly ERCP patients randomized to receive dexmedetomidine (Group D) or placebo (Group S). Group D received dexmedetomidine at 0.4 μg·kg-1·h-1 starting 15 minutes before surgery until completion, along with propofol at 1.5 mg/kg for anesthesia. Group S received saline and propofol in a similar manner. Anesthesia was maintained with dexmedetomidine at 0.4 μg·kg-1·h-1 and propofol at 1-2 mg/kg during surgery. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) preoperatively and on postoperative days 1, 3, and 5. Primary outcome was perioperative neurocognitive disorder (PND) incidence on day 5; secondary outcomes included changes in perioperative IL-6, cortisol, S100-β, hemodynamics, anesthesia parameters, postoperative pain, agitation scores, and adverse events.

Results

All 80 patients completed the trial. On postoperative day 5, the cumulative probability of PND incidence was significantly lower in Group D than in Group S (12.5% vs 35%, P=0.018). Group D also had lower levels of IL-6 (F=199.472, P<0.001), S100-β (F=2681.964, P<0.001), and cortisol (F=137.637, P<0.001). Propofol doses were lower in Group D (706.1 ± 202.4 vs 1003.3 ± 203.7, P<0.001), and bradycardia rates were higher (45% vs 15%, P=0.003), though atropine use did not significantly differ between groups. Group D showed greater stability in mean arterial pressure. Postoperative complications and adverse reactions were similar across groups.

Conclusion

Perioperative low-dose dexmedetomidine infusion with propofol in elderly ERCP patients ensures safe and effective monitored anesthesia care (MAC), reducing PND incidence by mitigating peripheral inflammation and stress responses. Long-term follow-up is needed to fully evaluate PND incidence.

Potential vicious cycle between postoperative pain and sleep disorders: A bibliometric analysis

Background

Surgical pain affects postoperative sleep quality, and they jointly form a vicious cycle of mutual influence. The cycle of postoperative pain and sleep disorders could lead to delirium, cardiovascular disease, and hyperalgesia, which significantly affect patients' postoperative recovery. Thus, exploring this phenomenon is of great importance for surgical patients, and warrants further investigation.

Objective

By employing bibliometric methods, this study systematically analyzes the publications on postoperative pain-sleep disorders, identifies research trends and field dynamics, and ultimately provides insights for further progress in this research area.

Methods

In this study, we searched the Web of Science database for studies on postoperative pain and sleep disorders from 2013 to 2023, and analyzed the number of publications, journals, authors, institutions, country regions, and keywords by utilizing CiteSpace, VOSviewer, and Bibliometrix.

Results

The 1894 retrieved publications showed a trend of increasing number of publications and correlations between postoperative pain and sleep disorders from 2013 to 2023. The top countries for publications included the USA, China, etc., establishing a global collaborative network centered around the USA, China, and Europe. The top institutions for publications included University of California System, Harvard University, etc. The top authors include Christine Miaskowski, Steven M. Paul, Qiuling Shi, etc. These publications involved multiple disciplines including surgery, neurology, and anesthesiology, and various research funds including NIH, HHS, NSFC, etc. The top journals for publications included the European Archives of Oto-Rhino-Laryngology, etc. Keywords that appear most frequently in this field include "pain", "surgery", "quality of life", "sleep", "depression", and "outcomes". The thematic map indicated that the hot topics in this area include obstructive sleep apnea, tonsillectomy, children, pain, quality of life, and sleep. The undeveloped topics with research potential included postoperative pain, analgesia and dexmedetomidine, breast cancer, fatigue, and lung cancer.

Conclusion

The increased number of publications and correlations between postoperative pain and sleep disorders, and the collaborative network across the USA, China, and Europe indicate a growing global interest in this area. This study also provides valuable insights into the trend of hot topics and frontiers and shows that this is an evolving and dynamic research area.

Electroencephalographic guided propofol-remifentanil TCI anesthesia with and without dexmedetomidine in a geriatric population: electroencephalographic signatures and clinical evaluation

Elderly and multimorbid patients are at high risk for developing unfavorable postoperative neurocognitive outcomes; however, well-adjusted and EEG-guided anesthesia may help titrate anesthesia and improve postoperative outcomes. Over the last decade, dexmedetomidine has been increasingly used as an adjunct in the perioperative setting. Its synergistic effect with propofol decreases the dose of propofol needed to induce and maintain general anesthesia. In this pilot study, we evaluate two highly standardized anesthetic regimens for their potential to prevent burst suppression and postoperative neurocognitive dysfunction in a high-risk population. Prospective, randomized clinical trial with non-blinded intervention. Operating room and post anesthesia care unit at Hospital Base San José, Osorno/Universidad Austral, Valdivia, Chile. 23 patients with scheduled non-neurologic, non-cardiac surgeries with age > 69 years and a planned intervention time > 60 min. Patients were randomly assigned to receive either a propofol-remifentanil based anesthesia or an anesthetic regimen with dexmedetomidine-propofol-remifentanil. All patients underwent a slow titrated induction, followed by a target controlled infusion (TCI) of propofol and remifentanil (n = 10) or propofol, remifentanil and continuous dexmedetomidine infusion (n = 13). We compared the perioperative EEG signatures, drug-induced changes, and neurocognitive outcomes between two anesthetic regimens in geriatric patients. We conducted a pre- and postoperative Montreal Cognitive Assessment (MoCa) test and measured the level of alertness postoperatively using a sedation agitation scale to assess neurocognitive status. During slow induction, maintenance, and emergence, burst suppression was not observed in either group; however, EEG signatures differed significantly between the two groups. In general, EEG activity in the propofol group was dominated by faster rhythms than in the dexmedetomidine group. Time to responsiveness was not significantly different between the two groups (p = 0.352). Finally, no significant differences were found in postoperative cognitive outcomes evaluated by the MoCa test nor sedation agitation scale up to one hour after extubation. This pilot study demonstrates that the two proposed anesthetic regimens can be safely used to slowly induce anesthesia and avoid EEG burst suppression patterns. Despite the patients being elderly and at high risk, we did not observe postoperative neurocognitive deficits. The reduced alpha power in the dexmedetomidine-treated group was not associated with adverse neurocognitive outcomes.

Dexmedetomidine Promotes NREM Sleep by Depressing Oxytocin Neurons in the Paraventricular Nucleus in Mice

Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist with sedative effects on sleep homeostasis. Oxytocin-expressing (OXT) neurons in the paraventricular nucleus (PVN) of the hypothalamus (PVNOXT) regulate sexual reproduction, drinking, sleep-wakefulness, and other instinctive behaviors. To investigate the effect of DEX on the activity and signal transmission of PVNOXT in regulating the sleep-wakefulness cycle. Here, we employed OXT-cre mice to selectively target and express the designer receptors exclusively activated by designer drugs (DREADD)-based chemogenetic tool hM3D(Gq) in PVNOXT neurons. Combining chemogenetic methods with electroencephalogram (EEG) /electromyogram (EMG) recordings, we found that cannula injection of DEX in PVN significantly increased the duration of non-rapid eye movement (NREM) sleep in mice. Furthermore, the chemogenetic activation of PVNOXT neurons using i.p. injection of clozapine N-oxide (CNO) after cannula injection of DEX to PVN led to a substantial increase in wakefulness. Electrophysiological results showed that DEX decreased the frequency of action potential (AP) and the spontaneous excitatory postsynaptic current (sEPSC) of PVNOXT neurons through α2-adrenoceptors. Therefore, these results identify that DEX promotes sleep and maintains sleep homeostasis by inhibiting PVNOXT neurons through the α2-adrenoceptor.

Pharmacological and non-pharmacological prevention and management of delirium in critically ill and palliative patients in the inpatient setting: a review

Introduction

This review explores delirium in critically ill patients in the inpatient setting, focusing on its prevention and management. It evaluates the efficacy of both current pharmacological and non-pharmacological interventions, aiming to provide a comprehensive overview.

Methods

A systematic literature search was conducted to identify relevant studies investigating the prevention and management of delirium resulting in a final sample of 26 articles for analysis.

Results

Of the 26 articles analyzed for this review (N = 8,831 participants) of controlled trials, 16 studies examined the prevention of delirium, 9 explored the treatment of delirium, and 1 investigated both prevention and treatment of delirium.

Discussion

Among the reviewed studies, there is evidence that non-pharmacologic methods are effective in the prevention of delirium. Evidence regarding pharmacological interventions for delirium prevention is varied and inconclusive, with some indication that atypical antipsychotics like aripiprazole and quetiapine may reduce the incidence of delirium. Regarding the treatment of delirium, there is limited evidence supporting the use of pharmacological agents. Additional double-blinded, randomized, placebo-controlled clinical trials are needed to investigate the efficacy of pharmacologic agents for diverse hospitalized populations.

Mapping Theme Trends and Research Frontiers in Dexmedetomidine Over Past Decade: A Bibliometric Analysis

Background

Dexmedetomidine, an α2-adrenergic receptor (α2-AR) agonist, is extensively used in clinical and animal studies owing to its sedative, analgesic, and anxiolytic effects. The diverse range of research domains associated with dexmedetomidine poses challenges in defining pivotal research directions. Therefore, this study aimed to conduct a qualitative and quantitative bibliometric study in the field of dexmedetomidine over the past decade to establish current research trends and emerging frontiers.

Methods

Relevant publications in the field of dexmedetomidine between 2014 and 2023 were extracted from the Web of Science Core Collection database. The bibliometric analysis, incorporating statistical and visual analyses, was conducted using CiteSpace (6.1.R6) and R (4.3.1).

Results

The present study encompassed a total of 5,482 publications, exhibiting a consistent upward trend over the past decade. The United States and its institutions had the highest centrality. Ji, Fuhai, and Ebert, Thomas J. were identified as the most productive author and the most cited author, respectively. As anticipated, the most cited journal was Anesthesiology. Moreover, cluster analysis of cited references and co-occurrence of keywords revealed that recent studies were primarily focused on sedation, delirium, and opioid-free anesthesia. Finally, a timeline view of keywords clusters and keywords burst demonstrated that primary research frontiers were stress response, neuroinflammation, delirium, opioid-free anesthesia, peripheral nerve block, and complications.

Conclusion

Current research trends and directions are focused on sedation, delirium, and opioid-free anesthesia, as evidenced by our results. The frontier of future research is anticipated to encompass basic investigations into dexmedetomidine, including stress response and neuroinflammation, as well as clinical studies focusing on delirium, opioid-free anesthesia, peripheral nerve block, and associated complications.

Intravenous Methadone versus Intrathecal Morphine as Part of an Enhanced Recovery After Cardiac Surgery Protocol on Postoperative Pain and Outcomes: A Retrospective Cohort Study

OBJECTIVES

Evaluate the effect of intravenous (IV) methadone versus intrathecal morphine (ITM) within an Enhanced Recovery After Cardiac Surgery (ERACS) pathway on postoperative pain and outcomes (length of hospital stay and postoperative complications) after cardiac surgery.

DESIGN

Retrospective cohort study.

SETTING

Two tertiary academic medical institutions within the same health system.

PARTICIPANTS

Eligible 289 adult patients undergoing elective cardiac surgery with an enhanced recovery pathway from January 2020 through July 2021.

INTERVENTIONS

Patients were administered ITM (0.25 mg) or IV methadone (0.1 mg/kg) if ITM was contraindicated. All patients were enrolled in an ERACS pathway using current Enhanced Recovery After Surgery society guidelines.

MEASUREMENTS AND MAIN RESULTS

Primary outcome measures included postoperative pain scores and opioid consumption measured as oral morphine equivalents. We analyzed patient demographics, procedural factors, intraoperative medications, and outcomes. Adjusted linear mixed models were fit to analyze associations between intervention and pain outcomes. ITM was associated with decrease in pain scores on postoperative day 0 after adjusting for clinical variables (average marginal effect, 0.49; 95% confidence interval, 0.002-0.977; p = 0.049). No difference in opioid consumption could be demonstrated between groups after adjusting for postoperative day and other variables of interest.

CONCLUSIONS

ITM when compared with IV methadone was associated with a decrease in pain scores without any difference in opioid consumption after elective cardiac surgery. Methadone can be considered as a safe and effective alternative to ITM for ERACS protocols. Future large prospective studies are needed to validate this finding and further improve analgesia and safety.

The role of anesthesia in peri‑operative neurocognitive disorders: Molecular mechanisms and preventive strategies

Peri-operative neurocognitive disorders (PNDs) include postoperative delirium (POD) and postoperative cognitive dysfunction (POCD). Children and the elderly are the two populations most vulnerable to the development of POD and POCD, which results in both high morbidity and mortality. There are many factors, including neuroinflammation and oxidative stress, that are associated with POD and POCD. General anesthesia is a major risk factor of PNDs. However, the molecular mechanisms of PNDs are poorly understood. Dexmedetomidine (DEX) is a useful sedative agent with analgesic properties, which significantly improves POCD in elderly patients. In this review, the current understanding of anesthesia in PNDs and the protective effects of DEX are summarized, and the underlying mechanisms are further discussed.

Absorption pharmacokinetics and feasibility of intranasal dexmedetomidine in patients under general anaesthesia

BACKGROUND

The use of intranasal dexmedetomidine is hampered by a limited understanding of its absorption pharmacokinetics.

METHODS

We examined the pharmacokinetics and feasibility of intranasal dexmedetomidine administered in the supine position to adult patients undergoing general anaesthesia. Twenty-eight patients between 35 and 80 years of age, ASA 1-3 and weight between 50 and 100 kg, who underwent elective unilateral total hip or knee arthroplasty under general anaesthesia were recruited. All patients received 100 μg of intranasal dexmedetomidine after anaesthesia induction. Six venous blood samples (at 0, 5, 15, 45, 60, 240 min timepoints from dexmedetomidine administration) were collected from each patient and dexmedetomidine plasma concentrations were measured. Concentration-time profiles after nasal administration were pooled with earlier data from a population analysis of intravenous dexmedetomidine (n = 202) in order to estimate absorption parameters using nonlinear mixed effects. Peak concentration (CMAX) and time (TMAX) were estimated using simulation (n = 1000) with parameter estimates and their associated variability.

RESULTS

There were 28 adult patients with a mean (SD) age of 66 (8) years and weight of 83 (10) kg. The mean weight-adjusted dose of dexmedetomidine was 1.22 (0.15) μg kg-1. CMAX 0.273 μg L-1 was achieved at 98 min after intranasal administration (TMAX). The relative bioavailability of dexmedetomidine was 80% (95% CI 75-91%). The absorption half-time (TABS = 120 min; 95% CI 90-147 min) was slower than that in previous pharmacokinetic studies on adult patients. Perioperative haemodynamics of all patients remained stable.

CONCLUSIONS

Administration of intranasal dexmedetomidine in the supine position during general anaesthesia is feasible with good bioavailability. This administration method has slower absorption when compared to awake patients in upright position, with consequent concentrations attained after TMAX for several hours.

Pharmacologic Sleep Aids in the Intensive Care Unit: A Systematic Review

Background: Patients in the intensive care unit (ICU) often experience poor sleep quality. Pharmacologic sleep aids are frequently used as primary or adjunctive therapy to improve sleep, although their benefits in the ICU remain uncertain. This review aims to provide a comprehensive assessment of the objective and subjective effects of medications used for sleep in the ICU, as well as their adverse effects. Methods: PubMed, Web of Science, Scopus, Embase, and Cochrane Central Register of Controlled Trials were systematically searched from their inception until June 2023 for comparative studies assessing the effects of pharmacologic sleep aids on objective and subjective metrics of sleep. Results: Thirty-four studies with 3498 participants were included. Medications evaluated were melatonin, ramelteon, suvorexant, propofol, and dexmedetomidine. The majority of studies were randomized controlled trials. Melatonin and dexmedetomidine were the best studied agents. Objective sleep metrics included polysomnography (PSG), electroencephalography (EEG), bispectral index, and actigraphy. Subjective outcome measures included patient questionnaires and nursing observations. Evidence for melatonin as a sleep aid in the ICU was mixed but largely not supportive for improving sleep. Evidence for ramelteon, suvorexant, and propofol was too limited to offer definitive recommendations. Both objective and subjective data supported dexmedetomidine as an effective sleep aid in the ICU, with PSG/EEG in 303 ICU patients demonstrating increased sleep duration and efficiency, decreased arousal index, decreased percentage of stage N1 sleep, and increased absolute and percentage of stage N2 sleep. Mild bradycardia and hypotension were reported as side effects of dexmedetomidine, whereas the other medications were reported to be safe. Several ongoing studies have not yet been published, mostly on melatonin and dexmedetomidine. Conclusions: While definitive conclusions cannot be made for most medications, dexmedetomidine improved sleep quantity and quality in the ICU. These benefits need to be balanced with possible hemodynamic side effects.

Global research and scientific publications on PND between 1969 and 2022: A bibliometric analysis

Objectives

We hope to offer a comprehensive understanding of the advancements and patterns in research on PND. Methods: We performed a thorough search on the Web of Science Core Collection to locate relevant studies published from 1969 to 2022 and utilized four distinct tools, namely VOSviewer (J Data Inf Sci, 2017, 2, 1; J Am Soc Inf Sci, 1973, 24, 265; Amer Doc, 1963, 14, 10 and Scientometrics, 2010, 82, 581), CiteSpace (Scientometrics, 2010, 84, 523), Scimago Graphica, and R-bibliometrix which allowed us to examine various aspects. Results: We included a total of 6787 articles and reviews for analysis which described PND research, the sources, and the subfields; highlighted the significant developments in this field; identified three main directions in PND.Conclusion: This study highlights the rapid growth of research on PND in recent years and provided an overview of previous studies in the field of PND, thereby establishing the overall landscape of PND research and identifying potential avenues for future investigations.

Methods

We performed a thorough search on the Web of Science Core Collection to locate relevant studies published from 1969 to 2022. To perform bibliometric analysis and network visualization, we utilized four distinct tools, namely VOSviewer (J Data Inf Sci, 2017, 2, 1; J Am Soc Inf Sci, 1973, 24, 265; Amer Doc, 1963, 14, 10 and Scientometrics, 2010, 82, 581), CiteSpace (Scientometrics, 2010, 84, 523), Scimago Graphica, and R-bibliometrix. These tools allowed us to examine various aspects, including the yearly publication output, the contribution of different countries or regions, the involvement of active journals, co-citation analysis, publication status, keywords, and terms, as well as scientific categories. We hope to offer a comprehensive understanding of the advancements and patterns in research on PND. The insights gained from this study can assist researchers and clinicians in enhancing the management and implementation of their work in this field.

Results

In this study, we included a total of 6787 articles and reviews for analysis. First, publication trends and contribution by country analysis described PND research. Second, a historical analysis described PND research, the sources, and the subfields. Third, an analysis of keywords highlighted the significant developments in this field. Fourth, an analysis of research themes identified three main directions in PND.

Conclusion

In summary, the research volume exhibits exponential growth over time. Furthermore, the majority of contributions originate from Western countries and China. The interdisciplinary nature of the field is evident, with its roots in biology and medicine and further branching into psychology and social sciences. POCD, delirium-predominant associated clinical management were major research themes about PND.

Alpha Alert: Utilization of Transdermal Clonidine for Refractory Agitation

Alpha-2 agonists are under-recognized for their class effects yet offer potential benefit in specialty palliative care via decreasing sympathetic output, inducing sedation, and modulating pain. Especially in clinical contexts where agitation predominates and patients are intolerant of oral medication route, transdermal medication delivery is advantageous. We report a case of agitated behaviors in setting of mixed Alzheimer/vascular-type dementia limiting hospital discharge to nursing facility that were ameliorated with transdermal clonidine. We suggest palliative clinicians routinely conceptualize the seemingly disparate alpha-2 agonists as a class for effective symptom palliation especially as new clinical evidence becomes available.

COVID-19 vaccination may prevent postoperative delirium in elderly patients undergoing elective non-cardiac surgery: The PNDRFAP and PNDABLE studies

Background

Postoperative delirium (POD) often occurs in elderly patients after surgery. We conducted two clinical studies to determine whether COVID-19 vaccination has a protective effect on POD and to explore the role of CSF biomarkers in this process.

Methods

We conducted two clinical studies, Perioperative Neurocognitive Disorder Risk Factor and Prognosis (PNDRFAP) and Perioperative Neurocognitive Disorder and Biomarker Lifestyle (PNDABLE), in which patients more than or equal to 65 years old who have had elective non-cardiac surgery were enrolled. The preoperative cognitive status of patients were evaluated by Mini-Mental State Examination (MMSE) one day preoperatively. Confusion Assessment Method (CAM) was used to diagnose POD. We used the mediation model to analyze the relationship between CSF biomarkers, COVID-19 vaccination and POD, as well as Dynamic Nomogram to calculate the incidence of Non-Postoperative Delirium (NPOD). The main outcome of these studies was the incidence of POD during seven days postoperatively or before discharge, which was assessed by CAM.

Results

In the final, 705 participants were enrolled in the PNDRFAP study, and 638 patients in the PNDABLE. In both studies, we found that the occurrence of POD was lower in patients who had injected COVID-19 vaccination before surgery compared with those without vaccination (PNDRFAP: 10.20 % [21/205] vs 25.80 % [129/500], P < 0.001; PNDABLE: 2.40 % [4/164] vs 34.60 % [164/474], P < 0.001). Mediation analysis showed that the protective effect of preoperative COVID-19 vaccine on POD was significantly mediated by CSF Aβ42 (proportion = 17.56 %), T-tau (proportion = 19.64 %), Aβ42/T-tau (proportion = 29.67 %), and Aβ42/P-tau (proportion = 12.26 %).

Conclusions

COVID-19 vaccine is a protective factor for POD in old patients, which is associated with CSF biomarkers.

Dexmedetomidine Attenuates Inflammation in Elderly Patients Following Major Hepatobiliary and Pancreatic Surgery: A Randomized Clinical Trial

Background

Dexmedetomidine (Dex) may have anti-inflammatory properties and potentially reduce the incidence of postoperative organ injury.

Objective

To investigate whether Dex protects pulmonary and renal function via its anti-inflammatory effects in elderly patients undergoing prolonged major hepatobiliary and pancreatic surgery.

Design and Setting

Between October 2019 and December 2020, this randomized controlled trial was carried out at a tertiary hospital in Chongqing, China.

Patients

86 patients aged 60-75 who underwent long-duration (> 4 hrs) hepatobiliary and pancreatic surgery without significant comorbidities were enrolled and randomly assigned into two groups at a 1:1 ratio.

Interventions

Patients were given either Dex or an equivalent volume of 0.9% saline (Placebo) with a loading dose of 1 μg kg-1 for 10 min, followed by 0.5 μg kg-1 hr-1 for maintenance until the end of surgery.

Main Outcome Measures

The changes in serum concentrations of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were primary outcomes.

Results

At one hour postoperatively, serum IL-6 displayed a nine-fold increase (P<0.05) in the Placebo group. Administration of Dex decreased IL-6 to 278.09 ± 45.43 pg/mL (95% CI: 187.75 to 368.43) compared to the Placebo group (P=0.019; 432.16 ± 45.43 pg/mL, 95% CI: 341.82 to 522.50). However, no significant differences in TNF-α were observed between the two groups. The incidence of postoperative acute kidney injury was twice as high in the Placebo group (9.30%) compared to the Dex group (4.65%), and the incidence of postoperative acute lung injury was 23.26% in the Dex group, lower than that in the Placebo group (30.23%), although there was no statistical significance between the two groups.

Conclusion

Dex administration in elderly patients undergoing major hepatobiliary and pancreatic surgery reduces inflammation and potentially protects kidneys and lungs.

Registration

Chinese Clinical Trials Registry, identifier: ChiCTR1900024162, on 28 June 2019.

Effects of Chinese traditional five-element music intervention on postoperative delirium and sleep quality in elderly patients after non-cardiac surgery: a randomized controlled trial

BACKGROUND

Postoperative delirium (POD) is a common neurologic disorder among elderly patients after non-cardiac surgery, which leads to various negative outcomes. Sleep disorder is considered an important cause of POD. The objective of this study was to investigate whether the Chinese traditional five-element music intervention could reduce POD by improving sleep quality in elderly patients undergoing non-cardiac surgery.

METHODS

A total of 132 patients aged 65 to 90 years who underwent non-cardiac surgery were randomized to two groups: the intervention (n = 60) and the control group (n = 63). Patients in the intervention group were subjected to the Chinese traditional five-element music intervention during the perioperative, while patients in the control group had no music intervention. POD was evaluated using the Confusion Assessment Method (CAM) in the first 5 days after surgery. The Richards‒Campbell Sleep Questionnaire (RCSQ) was used to assess subjective sleep quality. The levels of nocturnal melatonin and cortisol in saliva were measured on the preoperative and the first 2 postoperative days.

RESULTS

The incidence of POD within 5 days was 27.0% in the control group and 11.7% in the intervention group. Preoperative PSQI and MMSE scores were associated with POD. The RCSQ scores on the first postoperative day were significantly decreased in the two groups compared to the preoperative day. Compared to the control group, the RCSQ scores showed a significant improvement in the intervention group on the first postoperative day. Compared to the control group, the level of saliva melatonin in the intervention group showed a significant increase on the first postoperative day. However, there was no statistical difference in cortisol levels between the two groups.

CONCLUSIONS

Chinese traditional five-element music intervention decreased the incidence of POD in elderly patients who underwent noncardiac surgery via improving sleep quality, which may be associated with increased levels of melatonin.

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.

Association between pediatric postoperative delirium and regional cerebral oxygen saturation: a prospective observational study

BACKGROUND

Postoperative delirium (POD) represents a prevalent and noteworthy complication in the context of pediatric surgical interventions. In recent times, a hypothesis has emerged positing that cerebral ischemia and regional cerebral oxygen desaturation might serve as potential catalysts in the pathogenesis of POD. The primary aim of this study was to methodically examine the potential relationship between POD and regional cerebral oxygen saturation (rSO2) and to assess the predictive and evaluative utility of rSO2 in the context of POD.

METHODS

This prospective observational study was conducted at the Children's Hospital, Zhejiang University School of Medicine, Zhejiang, China, spanning the period from November 2020 to March 2021. The research cohort comprised children undergoing surgical procedures within this clinical setting. To measure rSO2 dynamics, cerebral near-infrared spectroscopy (NIRS) was used to monitor rSO2 levels both before and after surgery. In addition, POD was assessed in the paediatric patients according to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5) criteria. The analysis of the association between the rSO2 index and the incidence of POD was carried out through the application of either the independent samples t-test or the nonparametric rank-sum test. To ascertain the threshold value of the adjusted rSO2 index for predictive and evaluative purposes regarding POD in the pediatric population, the Receiver Operating Characteristics (ROC) curve was employed.

RESULTS

A total of 211 cases were included in this study, of which 61 (28.9%) developed POD. Participants suffering delirium had lower preoperative rSO2mean, lower preoperative rSO2min, and lower postoperative rSO2min, higher ∆rSO2mean, higher amount of ∆rSO2mean, lower ∆rSO2min (P < 0.05). Preoperative rSO2mean (AUC = 0.716, 95%CI 0.642-0.790), ∆rSO2mean (AUC = 0.694, 95%CI 0.614-0.774), amount of ∆rSO2mean (AUC = 0.649, 95%CI 0.564-0.734), preoperative rSO2min (AUC = 0.702, 96%CI 0.628-0.777), postoperative rSO2min (AUC = 0.717, 95%CI 0.647-0.787), and ∆rSO2min (AUC = 0.714, 95%CI 0.638-0.790) performed well in sensitivity and specificity, and the best threshold were 62.05%, 1.27%, 2.41%, 55.68%, 57.36%, 1.29%.

CONCLUSIONS

There is a close relationship between pediatric POD and rSO2. rSO2 could be used as an effective predictor of pediatric POD. It might be helpful to measure rSO2 with NIRS for early recognizing POD and making it possible for early intervention.

A Comparison of Efficacy between Low-dose Dexmedetomidine and Propofol for Prophylaxis of Postoperative Delirium in Elderly Patients Undergoing Hip Fracture Surgery: A Randomized Controlled Trial

Aims and background

The efficacy of dexmedetomidine and propofol in preventing postoperative delirium is controversial. This study aims to evaluate the efficacy of dexmedetomidine and propofol for preventing postoperative delirium in extubated elderly patients undergoing hip fracture surgery.

Materials and methods

This randomized controlled trial included participants undergoing hip fracture surgery. Participants were randomly assigned to receive dexmedetomidine, propofol, or placebo intravenously during intensive care unit (ICU) admission (8 p.m. to 6 a.m.). The drug dosages were adjusted to achieve the Richmond Agitation Sedation Scale (RASS) of 0 to -1. The primary outcome was postoperative delirium. The secondary outcomes were postoperative complications, fentanyl consumption, and length of hospital stay.

Results

108 participants were enrolled (n = 36 per group). Postoperative delirium incidences were 8.3%, 22.2%, and 5.6% in the dexmedetomidine, propofol, and placebo groups, respectively. The hazard ratios of dexmedetomidine and propofol compared with placebo were 1.49 (95% CI, 0.25, 8.95; p = 0.66) and 4.18 (95% CI, 0.88, 19.69; p = 0.07). The incidence of bradycardia was higher in the dexmedetomidine group compared with others (13.9%; p = 0.01) but not for hypotension (8.3%; p = 0.32). The median length of hospital stays (8 days, IQR: 7, 11) and fentanyl consumption (240 µg, IQR: 120, 400) were not different among groups.

Conclusion

This study did not successfully demonstrate the impact of nocturnal low-dose dexmedetomidine and propofol in preventing postoperative delirium among elderly patients undergoing hip fracture surgery. While not statistically significant, it is noteworthy that propofol exhibited a comparatively higher delirium rate.

How to cite this article

Ekkapat G, Kampitak W, Theerasuwipakorn N, Kittipongpattana J, Engsusophon P, Phannajit J, et al. A Comparison of Efficacy between Low-dose Dexmedetomidine and Propofol for Prophylaxis of Postoperative Delirium in Elderly Patients Undergoing Hip Fracture Surgery: A Randomized Controlled Trial. Indian J Crit Care Med 2024;28(5):467-474.

Advancing Perioperative Neurocognitive Health: A Critical Review of Predictive Tools, Diagnostic Methods, and Interventional Strategies

Perioperative neurocognitive disorders (PNDs) affect a large percentage of people who undergo surgeries that need general anesthesia. There is an increased risk of death and a major disruption to postoperative self-care as a result of this. This study compiles all the relevant materials that the authors have found to investigate postnatal depression and its causes, as well as the methods used to determine the probability and severity of PNDs and how to reduce their risk before surgery. Postnatal depression can have many causes, and this text explores some of them. These include a history of alcohol or opiate use, immunological dysregulation, advanced age, educational background, infections, neurocognitive impairment, and pre-existing chronic inflammatory disorders. It also delves into various methods used to gauge the likelihood and severity of postpartum depression. The following assessment tools were covered: the Clock Drawing Test, Domain-Specific Tests, the Mini-Mental State Examination, and the Montreal Cognitive Assessment. In addition to biochemical markers, neuroimaging techniques play an important role in diagnosis. The Frailty Fried assessment, which measures inertia, sluggishness, lack of physical activity, fatigue, and unintentional weight loss, is a key prognostic sign that is highlighted. There is strong evidence that the index, which is derived from these five characteristics, may accurately predict the likelihood of PNDs. Risk mitigation strategies are also covered in this research. Preoperative brain plasticity-based therapies, such as physical exercise and intensive cognitive training, can significantly reduce the incidence and severity of postoperative neurocognitive disorders. A peripheral nerve block, monitoring cerebral oxygen saturation, dexmedetomidine, and a reduction in anesthesia depth are all ways to improve anesthetic procedures. Methods that lower blood pressure should be avoided, the body temperature should be kept down during surgery, or the time without liquids should be lengthened; all of these raise the risk of postoperative nausea and vomiting and make it worse. Potential approaches include a Mediterranean diet, physical activity, cognitive stimulation, smoking cessation, alcohol reduction, avoidance of anticholinergic medications, and non-steroidal anti-inflammatory drug stewardship, although there is no definitive evidence for successful postoperative neurocognitive rehabilitation procedures. More standardized diagnostic criteria, evaluation methods, and PND classification are urgently needed, according to this study. Different cases of PNDs are characterized by different combinations of tests, cutoff values, and methods because there is a broad variety of diagnostic tests used to make the diagnosis. Until now, PNDs and pre-existing neurocognitive disorders have been diagnosed using the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). With an aging population comes an increase in the occurrence and prevalence of PNDs, which calls for a specific way to classify and describe the condition.

Association Between Preoperative Sleep Disturbance and Postoperative Delirium in Elderly: A Retrospective Cohort Study

Purpose

Postoperative sleep disturbance, characterized by diminished postoperative sleep quality, is a risk factor for postoperative delirium (POD); however, the association between pre-existing sleep disturbance and POD remains unclear. This study aimed to evaluate the association between preoperative sleep disturbance and POD in elderly patients after non-cardiac surgery.

Patients and methods

This retrospective cohort study was conducted at a single center and enrolled 489 elderly patients who underwent surgery between May 1, 2020, and March 31, 2021. Patients were divided into the sleep disorder (SD) and non-sleep disorder (NSD) groups according to the occurrence of one or more symptoms of insomnia within one month or sleep- Numerical Rating Scale (NRS)≥6 before surgery. The primary outcome was the incidence of POD. Propensity score matching analysis was performed between the two groups. Multiple logistic regression analysis was performed to identify the risk factors for POD.

Results

In both the unmatched cohort (16.0% vs 6.7%, P=0.003) and the matched cohort (17.0% vs 6.2%, P=0.023), the incidence of POD was higher in the SD group than in the NSD group. In addition, the postoperative sleep quality and the VAS score at postoperative 24 h were significantly lower in the SD group than in the NSD group. Multivariate logistic regression analysis indicated that age (Odds Ratio, 1.13 [95% CI: 1.04-1.23], P=0.003) and preoperative sleep disturbance (Odds Ratio, 3.03 [95% CI: 1.09-9.52], P=0.034) were independent risk factors for the development of POD.

Conclusion

The incidence of POD was higher in patients with pre-existing sleep disturbance than those without it. Whether improving sleep quality for preoperative sleep disturbance may help prevent POD remains to be determined.

Knowledge mapping and research trends on perioperative neurocognitive disorder from 1990 to 2022: a bibliometric analysis

Introduction

Perioperative neurocognitive disorder (PND) has attracted consistently increasing attention worldwide. However, there are few bibliometric studies that systematically evaluate this field. This study aimed to visualize the knowledge structure and research trends in PND through bibliometrics to help understand the future development of basic and clinical research.

Methods

Literature related to PND in Web of Science and PubMed from 1990 to 2022 were collected through keywords retrospectively. Additionally, the source information, citation information, etc. of these publications were extracted. Finally, bibliometric analysis was performed by visualization software and statistical software.

Results

There were 2837 articles and reviews in total. An exponential rise in PND-related publications was observed. China had the most publication, followed by the US and Germany. The institution with the most output and citations was Harvard University (149 papers, 8966 citations). The most prominent author was Marcantonio Edward R with 66 publications and 5721 citations. The journal with the highest productivity for PND research was Frontiers in Aging Neuroscience followed by Anesthesia and Analgesia. Keywords were identified as six topics, including postoperative delirium, postoperative neurocognitive disorder, cardiac surgery, anaesthesia, orthopedic surgery, and dementia. According to keyword analysis, the most recent popular keywords in PND research were prevention, older patients, emergence delirium, orthopedic surgery, and dexmedetomidine.

Conclusions

Publications on PND are increasing at an alarming rate from 1990 to 2022. Current research and future trends will concentrate on the prevention and treatment of PND, as well as PND associated with orthopedic surgery in older adults.

Dexmedetomidine adjunct to ropivacaine for ultrasound-guided transversus abdominis plane block for open inguinal hernia repair in the older adults: A randomised clinical trial

OBJECTIVE

The aim of this study was to evaluate the effect of adding dexmedetomidine to ropivacaine on pain relief and quality of recovery in older patients undergoing open inguinal hernia repair surgeries.

METHODS

This was a prospective and randomised clinical trial of 102 patients aged over 65 years who received an ultrasound-guided transversus open mesh herniorrhaphy abdominis plane (TAP) block with either 0.375% ropivacaine 20 ml (Group R, n = 47) or 0.375% ropivacaine combined with 1 μg/kg dexmedetomidine 20 ml (Group RD, n = 45) in the pre-anaesthesia care unit before elective open inguinal hernia surgeries. The primary outcome measure was Visual Analogue Scale (VAS) pain scores at rest and on movement at 2, 4, 8, 12 and 24 h and at 1 and 3 months' postoperatively. The secondary outcome measures were the incidence of post-operative delirium (POD), nausea and vomiting and the occurrence of side effects or complications on post-operative day 1.

RESULTS

Group RD had lower VAS scores at rest and on movement at 8 and 12 h postoperatively and a lower incidence of POD on the post-operative day 1 than Group R. Transient bradycardia was more frequent in Group RD than in Group R, and side effects or post-operative complications were reported in either group.

CONCLUSION

The addition of dexmedetomidine to ropivacaine in a TAP block enhances postoperative analgesia during hospitalisation and improves the quality of recovery without affecting chronic pain in older patients undergoing open inguinal hernia repair surgery.

Impact of anesthetics on rat hippocampus and neocortex: A comprehensive proteomic study based on label-free mass spectrometry

Anesthesia is regarded as an important milestone in medicine. However, the negative effect on memory and learning has been observed. In addition, the impact of anesthetics on postoperative cognitive functions is still discussed. In this work, in vivo experiment simulating a general anesthesia and ICU sedation was designed to assess the impact of two intravenous (midazolam, dexmedetomidine) and two inhalational (isoflurane, desflurane) agents on neuronal centers for cognition (neocortex), learning, and memory (hippocampus). More than 3600 proteins were quantified across both neocortex and hippocampus. Proteomic study revealed relatively mild effects of anesthetics, nevertheless, protein dysregulation uncovered possible different effect of isoflurane (and midazolam) compared to desflurane (and dexmedetomidine) to neocortical and hippocampal proteins. Isoflurane induced the upregulation of hippocampal NMDAR and other proteins of postsynaptic density and downregulation of GABA signaling, whereas desflurane and dexmedetomidine rather targeted mitochondrial VDAC isoforms and protein regulating apoptotic activity.

Postoperative cognitive dysfunction in elderly patients with colorectal cancer: A randomized controlled study comparing goal-directed and conventional fluid therapy

To investigate the impact of goal-directed fluid therapy (GDFT) on postoperative cognitive dysfunction (POCD) in elderly patients with colorectal cancer, we conducted a randomized controlled trial. Eighty elderly patients who underwent elective laparoscopic radical resection of colorectal cancer were randomly assigned to either the GDFT group or the conventional fluid therapy group. The primary outcome was the incidence of POCD during the initial 7 postoperative days, while secondary outcomes included inflammatory marker levels such as interleukin-6 (IL-6) and S100β protein, hemodynamics, level of lactic acid, postoperative functional recovery, and complications. Among 88 randomized patients, 80 were evaluable for the primary outcome. The incidence of POCD was significantly lower in the GDFT group (15.0%) compared to the conventional fluid therapy group (30.0%), with the highest occurrence observed on day 3 postoperatively in both groups (P < 0.05). IL-6 and S100β concentrations were consistently lower in the GDFT group than in the conventional fluid therapy group at the corresponding time points (P < 0.05). The GDFT group exhibited more stable perioperative hemodynamics and lower lactate levels (P < 0.05). Moreover, patients in the GDFT group exhibited better postoperative functional recovery indicators and a lower incidence of postoperative complications (P < 0.05). In summary, GDFT appears to reduce the incidence of early POCD, accelerate postoperative recovery, and enhance overall prognosis.

The feasibility of dexmedetomidine-led anesthesia maintenance strategy during major abdominal surgery

Background

Dexmedetomidine is known for its selective action on α2-adrenoceptor sites and is recognized for its neuroprotective capabilities. It can improve postoperative cognitive function. Commonly used anesthetics, such as sevoflurane and propofol, have been reported to affect postoperative cognitive function. Therefore, it could be valuable to explore dexmedetomidine-led anesthesia strategy. This study was designed to assess the performance, safety, and effective infusion rate in anesthesia maintenance, to explore a feasible dexmedetomidine-led anesthesia maintenance protocol, and to provide a foundation for potential combined anesthesia.

Methods

Thirty patients aged 18-60 years, classified as ASA I or II, undergoing abdominal surgery were involved. The anesthesia maintenance was achieved with dexmedetomidine, remifentanil and rocuronium. Dixon up-and-down sequential methodology was utilized to ascertain the ED50 of dexmedetomidine for maintaining Patient State Index (PSI) 25-40 (depth of stage III anesthesia). Intraoperative HR, BP and depth of anesthesia were monitored and controlled. The wake-up time from anesthesia, the incidence of intraoperative awareness and postoperative delirium, and the patients' satisfaction were assessed.

Results

The results indicated that dexmedetomidine-led anesthesia could maintain the depth of stage III anesthesia during abdominal surgery. The ED50 and ED95 of dexmedetomidine infusion rates during anesthesia maintenance were 2.298 μg/kg·h (95%CI: 2.190-2.404 μg/kg·h) and 3.765 μg/kg·h (95%CI: 3.550-4.050 μg/kg·h). Continuous infusion of dexmedetomidine and 0.1-0.3 μg/kg·min remifentanil could maintain PSI 25-40, and provide appropriate anesthesia depth for abdominal surgery. Perioperative bradycardia and hypertension could be rapidly corrected with atropine and nitroglycerin. The median wake-up time after anesthesia was 4.8 min, the perioperative maximum HR had significant correlation with wake-up time and intraoperative dexmedetomidine dose. No intraoperative awareness and postoperative delirium occurred; the patients were satisfied with dexmedetomidine-led anesthesia.

Conclusions

dexmedetomidine-led strategy could maintain stable depth of anesthesia throughout surgery, and the ED50 of dexmedetomidine infusion rates was 2.298 μg/kg·h. Intraoperative HR, BP and depth of anesthesia require monitoring, the bradycardia and hypertension could be rapidly corrected.

Melatonin regulates the circadian rhythm to ameliorate postoperative sleep disorder and neurobehavioral abnormalities in aged mice

BACKGROUND

Postoperative sleep disorder (PSD) and delirium, which may be associated with surgery and inhalational anesthetics, induce adverse effects in old adults. Emerging evidence indicates that circadian rhythm contributes to various neuropathological diseases, including Alzheimer's disease. Thus, we analyzed the potential role of circadian rhythm in PSD and delirium-like behavior in aged mice and determined whether exogenous melatonin could facilitate entrainment of the circadian rhythm after laparotomy under sevoflurane anesthesia.

METHODS

We selected old C57BL/6J mice which receiving laparotomy/sevoflurane anesthesia as model animals. We employed buried food, open field, and Y maze test to assess delirium-like behavior, and electroencephalography/electromyography (EEG/EMG) were used to investigate sleep changes. We analyzed the transcription rhythm of clock genes in superchiasmatic nucleus (SCN) to explore the effects of surgery and melatonin pretreatment on the circadian rhythm. Then, we measured melatonin receptor levels in SCN and ERK/CREB pathway-related proteins in hippocampus and prefrontal cortex to assess their role in PSDs and delirium-like behavior.

RESULTS

Laparotomy under sevoflurane anesthesia had a greater influence than sevoflurane alone, leading to sleep disorder, a shift in sleep-wake rhythm, and delirium-like behavior. Bmal1, Clock, and Cry1 mRNA expression showed a peak shift, MT1 melatonin receptor expression level was increased in the SCN, and p-ERK/ERK and p-CREB/CREB were decreased in hippocampus and prefrontal cortex of aged mice 1 day after laparotomy. Melatonin showed significant efficacy in ameliorating PSD and delirium-like behavior and restoring the circadian rhythm, reversing melatonin receptor and ERK/CREB pathway expression abnormalities. In addition, most of the beneficial effect of melatonin was antagonized by luzindole, a melatonin receptor antagonist.

CONCLUSIONS

Melatonin receptors in SCN, circadian rhythm, and ERK/CREB signaling pathway participate in the pathophysiological processes of PSD and delirium-like behavior. Melatonin intervention could be a potential preventative approach for PSD and delirium.

Association of sleep quality on the night of operative day with postoperative delirium in elderly patients: A prospective cohort study

BACKGROUND

Sleep disturbances in the peri-operative period have been associated with adverse outcomes, including postoperative delirium (POD). However, research on sleep quality during the immediate postoperative period is limited.

OBJECTIVES

This study aimed to investigate the association between sleep quality on the night of the operative day assessed using the Sleep Quality Numeric Rating Scale (SQ-NRS), and the incidence of POD in a large cohort of surgical patients.

DESIGN

A prospective cohort study.

SETTING

A tertiary hospital in China.

PATIENTS

This study enrolled patients aged 65 years or older undergoing elective surgery under general anaesthesia. The participants were categorised into the sleep disturbance and no sleep disturbance groups according to their operative night SQ-NRS.

MAIN OUTCOME MEASURES

The primary outcome was delirium incidence, whereas the secondary outcomes included acute kidney injury, stroke, pulmonary infection, cardiovascular complications and all-cause mortality within 1 year postoperatively.

RESULTS

In total, 3072 patients were included in the analysis of this study. Among them, 791 (25.72%) experienced sleep disturbances on the night of operative day. Patients in the sleep disturbance group had a significantly higher risk of developing POD (adjusted OR 1.43, 95% CI 1.11 to 1.82, P  = 0.005). Subgroup analysis revealed that age 65-75 years; male sex; ASA III and IV; haemoglobin more than 12 g l -1 ; intra-operative hypotension; surgical duration more than 120 min; and education 9 years or less were significantly associated with POD. No interaction was observed between the subgroups. No significant differences were observed in the secondary outcomes, such as acute kidney injury, stroke, pulmonary infection, cardiovascular complications and all-cause mortality within 1 year postoperatively.

CONCLUSIONS

The poor subjective sleep quality on the night of operative day was independently associated with increased POD risk, especially in certain subpopulations. Optimising peri-operative sleep may reduce POD. Further research should investigate potential mechanisms and causal relationships.

TRIAL REGISTRY

chictr.org.cn: ChiCTR1900028545.

Effect of dexmedetomidine infusion on postoperative sleep disturbances in women with breast cancer: A monocentric randomized-controlled double-blind trial

BACKGROUND

Most women with breast cancer are prone to postoperative sleep disturbances (POSD). Little is known about the differences between sevoflurane and propofol combined with dexmedetomidine on POSD in the same context. We investigated the effect of intra-operative sevoflurane or propofol combined with intravenous dexmedetomidine on the incidence of POSD and postoperative sleep structures.

METHODS

A monocentric, randomized-controlled, double-blind trial. Female patients undergoing radical surgery for breast cancer were randomly assigned to receive sevoflurane and placebo, sevoflurane and dexmedetomidine, propofol and placebo, or propofol and dexmedetomidine. Dexmedetomidine was administered at 1.0 μg kg-1 infusion 15 min before induction, then infused at 0.4 μg kg-1 h-1 until the surgical drain started to be placed. The primary outcome was the incidence of POSD within the postoperative first three days (defined as an Athens Insomnia Scale score ≥ 6 points on at least one day of postoperative first three days). The secondary outcome was the duration of sleep structures, collected from the Fitbit Charge 2® smart bracelet (Fitbit, Inc., San Francisco, CA, USA).

RESULTS

There were 188 women analyzed with the modified intention-to-treat method. The incidences of POSD in the dexmedetomidine and placebo groups were similar (p = 0.649). In the sevoflurane sedation strategy, dexmedetomidine decreased nocturnal wakefulness on postoperative first day (p = 0.001). In the propofol sedation strategy, dexmedetomidine increased nocturnal deep sleep on postoperative first (p < 0.001) and third (p < 0.001) days.

CONCLUSION

Intra-operative infusion of dexmedetomidine had no significant effect on POSD but decreased nocturnal wakefulness in the sevoflurane group and increased nocturnal deep sleep in the propofol group.

TRIAL REGISTRATION

Registered at www.chictr.org.cn (ChiCTR2300070136).

Update of the European Society of Anaesthesiology and Intensive Care Medicine evidence-based and consensus-based guideline on postoperative delirium in adult patients

Postoperative delirium (POD) remains a common, dangerous and resource-consuming adverse event but is often preventable. The whole peri-operative team can play a key role in its management. This update to the 2017 ESAIC Guideline on the prevention of POD is evidence-based and consensus-based and considers the literature between 01 April 2015, and 28 February 2022. The search terms of the broad literature search were identical to those used in the first version of the guideline published in 2017. POD was defined in accordance with the DSM-5 criteria. POD had to be measured with a validated POD screening tool, at least once per day for at least 3 days starting in the recovery room or postanaesthesia care unit on the day of surgery or, at latest, on postoperative day 1. Recent literature confirmed the pathogenic role of surgery-induced inflammation, and this concept reinforces the positive role of multicomponent strategies aimed to reduce the surgical stress response. Although some putative precipitating risk factors are not modifiable (length of surgery, surgical site), others (such as depth of anaesthesia, appropriate analgesia and haemodynamic stability) are under the control of the anaesthesiologists. Multicomponent preoperative, intra-operative and postoperative preventive measures showed potential to reduce the incidence and duration of POD, confirming the pivotal role of a comprehensive and team-based approach to improve patients' clinical and functional status.

Enhanced recovery pathways for head and neck surgery with free tissue transfer reconstruction

The enhanced recovery after surgery (ERAS) pathway is designed to facilitate recovery after surgery by packaging evidence-based protocols specific to each aspect of the perioperative period, including the preoperative, intraoperative, postoperative, and post-discharge periods. The ERAS pathway, which was originally developed for use with colonic resection, is now being expanded to include a variety of surgical procedures, and the ERAS Society has published a consensus review of the ERAS pathway for head and neck surgery with free tissue transfer reconstruction (HNS-FTTR). The ERAS pathway for HNS-FTTR consists of various important protocols, including early postoperative mobilization, early postoperative enteral nutrition, abolition of preoperative fasting, preoperative enteral fluid loading, multimodal pain management, and prevention of postoperative nausea and vomiting. In recent years, meta-analyses investigating the utility of the ERAS pathway in head and neck cancer surgery have also been presented, and all reports showed that the length of the postoperative hospital stay was reduced by the implementation of the ERAS pathway. The ERAS pathway is now gaining traction in the field of head and neck surgery; however, the details of its efficacy remain uncertain. We believe the future direction will require research focused on improving the quality of postoperative patient recovery and patient satisfaction. It will be important to use patient-reported outcomes to determine whether the ERAS pathway is actually beneficial.

Postoperative cognitive dysfunction-current research progress

Postoperative cognitive dysfunction (POCD) commonly occurs after surgery, particularly in elderly individuals. It is characterized by a notable decline in cognitive performance, encompassing memory, attention, coordination, orientation, verbal fluency, and executive function. This reduction in cognitive abilities contributes to extended hospital stays and heightened mortality. The prevalence of POCD can reach 40% within 1 week following cardiovascular surgery and remains as high as 17% 3 months post-surgery. Furthermore, POCD exacerbates the long-term risk of Alzheimer's disease (AD). As a result, numerous studies have been conducted to investigate the molecular mechanisms underlying POCD and potential preventive strategies. This article provides a review of the research progress on POCD.

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.

Dexmedetomidine Infusion Versus Placebo During Light or Deep Anesthesia on Postoperative Delirium in Older Patients Undergoing Major Noncardiac Surgery: A Pilot Randomized Factorial Trial

BACKGROUND

Postoperative delirium (POD) is common among older surgical patients and may be affected by dexmedetomidine and depth of anesthesia. We designed this pilot study to assess the feasibility of comparing dexmedetomidine with normal saline during light versus deep anesthesia on POD in older patients undergoing major noncardiac surgery.

METHODS

In this pilot randomized factorial study, 80 patients aged 60 years or older undergoing major noncardiac surgery were randomized (1:1:1:1) to receive dexmedetomidine infusion 0.5 μg/kg/h or normal saline placebo during light (bispectral index [BIS] target 55) or deep (BIS target 40) anesthesia. Feasibility end points included consent rate and dropout rate, timely enrollment, blinded study drug administration throughout surgery, no inadvertent unmasking, achieving BIS target throughout >70% of surgery duration, and the process of twice-daily POD screening. In addition, we estimated the POD incidences in the 2 control groups (placebo and deep anesthesia) and treatment effects of dexmedetomidine and light anesthesia.

RESULTS

Between November 1, 2021, and June 30, 2022, 78 patients completed the trial (mean [standard deviation, SD] age, 69.6 [4.6] years; 48 male patients [62%]; dexmedetomidine-deep, n = 19; dexmedetomidine-light, n = 20; placebo-deep, n = 19; placebo-light, n = 20). This study had a high consent rate (86%) and a low dropout rate (2.5%). Average recruitment was 5 patients at each center per month. Dexmedetomidine and normal saline were administered in a blinded fashion in all patients. Unmasking did not occur in either group. Approximately 99% of patients received the scheduled study drug infusion throughout the surgery. Approximately 81% of patients achieved the BIS targets throughout >70% of the surgery duration. The scheduled twice-daily POD screening was completed without exception. Overall, 10 of the 78 patients (13%; 95% confidence interval [CI], 7%-22%) developed POD. For the 2 reference groups, POD was observed in 7 of the 39 patients (17.9%; 95% CI, 9%-32.7%) in the placebo group and 7 of the 38 patients (18.4%; 95% CI, 9.2%-33.4%) in the deep anesthesia group. Regarding the treatment effects on POD, the estimated between-group difference was -10% (95% CI, -28% to 7%) for dexmedetomidine versus placebo, and -11% (95% CI, -28% to 6%) for light versus deep anesthesia.

CONCLUSIONS

The findings of this pilot study demonstrate the feasibility of assessing dexmedetomidine versus placebo during light versus deep anesthesia on POD among older patients undergoing major noncardiac surgery, and justify a multicenter randomized factorial trial.

A Rapid Systematic Review of Pharmacologic Sleep Promotion Modalities in the Intensive Care Unit

Background: The Society of Critical Care Medicine Clinical Practice Guidelines for Management of Pain, Agitation, Delirium, Immobility, and Sleep recommend protocolized non-pharmacologic sleep improvement. Pharmacologic interventions are frequently initiated to promote sleep but the evidence supporting these strategies remains controversial. Purpose: To systematically search and synthesize evidence evaluating pharmacologic sleep promotion modalities in critically ill adults. Methods: A rapid systematic review protocol was used to search Medline, Cochrane Library, and Embase for reports published through October 2022. We included randomized controlled trials (RCTs) and before-and-after cohort studies evaluating pharmacologic modalities intended to improve sleep in adult intensive care unit (ICU) patients. Sleep-related endpoints were the primary outcome of interest. Study and patient characteristics and relevant safety and non-sleep outcome data were also collected. The Cochrane Collaboration Risk of Bias or Risk of Bias in Non-Randomized Studies of Interventions were used to assess the risk of bias for all included studies. Results: Sixteen studies (75% RCTs) enrolling 2573 patients were included; 1207 patients were allocated to the pharmacologic sleep intervention. Most studies utilized dexmedetomidine (7/16; total n = 505 patients) or a melatonin agonist (6/16; total n = 592 patients). Only half of the studies incorporated a sleep promotion protocol as standard of care. Most (11/16, 68.8%) studies demonstrated a significant improvement in ≥1 sleep endpoint (n = 5 dexmedetomidine, n = 3 melatonin agonists, n = 2 propofol/benzodiazepines). Risk of bias was generally low for RCTs and moderate-severe for cohort studies. Conclusions: Dexmedetomidine and melatonin agonists are the most studied pharmacologic sleep promotion modalities, but current evidence does not support their routine administration in the ICU to improve sleep. Future RCTs evaluating pharmacologic modalities for ICU sleep should consider patients' baseline and ICU risks for disrupted sleep, incorporate a non-pharmacologic sleep improvement protocol, and evaluate the effect of these medication interventions on circadian rhythm, physiologic sleep, patient-perceived sleep quality, and delirium.

Risk factors, preventive interventions, overlapping symptoms, and clinical measures of delirium in elderly patients

Delirium is an acute reversible neuropsychiatric syndrome caused by multiple factors. It is associated with many adverse clinical outcomes including cognitive impairment, functional decline, prolonged hospitalization, and increased nursing service. The prevalence of delirium was high in department of cardiology, geriatric, and intensive care unit of hospital. With the increase in the aged population, further increases in delirium seem likely. However, it remains poorly recognized in the clinical practice. This article comprehensively discusses the latest research perspectives on the epidemiological data, risk factors, preventive interventions, overlapping symptoms, and clinical measures of delirium, including specific measures to manage delirium in clinical real-world situations. This article helps readers improve their knowledge and understanding of delirium and helps clinicians quickly identify and implement timely therapeutic measures to address various delirium subtypes that occur in the clinical settings to ensure patients are treated as aggressively as possible.

A pre-anesthetic bolus of ketamine versus dexmedetomidine for prevention of postoperative delirium in elderly patients undergoing emergency surgery: a randomized, double-blinded, placebo-controlled study

BACKGROUND

We aimed to evaluate whether a single dose of ketamine or dexmedetomidine before induction of general anesthesia could reduce the incidence of postoperative delirium (primary outcome) or cognitive dysfunction (secondary outcome) in elderly patients undergoing emergency surgery.

PATIENTS AND METHODS

This randomized, double-blinded, placebo-controlled trial included 60 elderly patients who were scheduled for emergency surgery. The patients were randomly assigned into one of three groups (n = 20): group I received 0.9% normal saline, group II received 1 µg/kg dexmedetomidine, and group III received 1 mg/kg ketamine right before anesthesia induction. Patients were observed for three days after surgery and tested for postoperative delirium and cognitive dysfunction using the delirium observation screening scale and the mini-mental state examination score, respectively.

RESULTS

The dexmedetomidine group had the lowest incidence of delirium (p = 0.001) and cognitive dysfunction (p = 0.006) compared to the ketamine and placebo groups. The multivariate logistic regression model revealed that dexmedetomidine reduced the incidence of postoperative delirium by 32% compared to placebo (reference) (OR = 0.684, 95% CI: 0.240-0.971, p = 0.025), whereas ketamine increased the risk by threefold (OR = 3.012, 95% CI: 1.185-9.681, p = 0.013). Furthermore, dexmedetomidine reduced the incidence of postoperative cognitive dysfunction by 62% (OR = 0.375, 95% CI: 0.091-0.543, p = 0.012), whereas ketamine increased the risk by 4.5 times (OR = 4.501, 95% CI: 1.161-8.817, p = 0.006).

CONCLUSION

A single pre-anesthetic bolus of dexmedetomidine is a practical choice for preventing postoperative delirium in elderly patients undergoing emergency surgery.

TRIAL REGISTRATION

This study was approved by the Ethics Committee of Aswan University Hospital (approval number: aswu/548/7/2021; registration date: 06/07/2021) and registered on ClinicalTrials.gov (NCT05341154) (22/04/2022).

Effectiveness of sleep interventions to reduce delirium in critically ill patients: A systematic review and meta-analysis

PURPOSE

To analyze the effectiveness of sleep interventions in reducing the incidence and duration of delirium in the ICU.

MATERIALS AND METHODS

We searched the PubMed, Embase, CINAHL, Web of Science, Scopus, and Cochrane databases for relevant randomized controlled trials from inception to August 2022. Literature screening, data extraction, and quality assessment were performed independently by two investigators. Data from the included studies were analyzed using Stata and TSA software.

RESULTS

Fifteen randomized controlled trials were eligible. Meta-analysis showed that the sleep intervention was associated with a reduced incidence of delirium in the ICU (RR = 0.73, 95% CI = 0.58 to 0.93, p < 0.001) compared to the control group. The results of the trial sequence analysis further confirm that sleep interventions are effective in reducing the occurrence of delirium. Pooled data from the three dexmedetomidine trials showed significant differences in the incidence of ICU delirium between groups (RR = 0.43, 95% CI = 0.32 to 0.59, p < 0.001). The respective pooled results of other sleep interventions (e.g., light therapy, earplugs, melatonin, and multicomponent nonpharmacologic treatments) did not find a significant effect on reducing the incidence and duration of ICU delirium (p > 0.05).

CONCLUSIONS

The current evidence suggests that non-pharmacological sleep interventions are not effective in preventing delirium in ICU patients. However, limited by the number and quality of included studies, future well-designed multicenter randomized controlled trials are still needed to validate the results of this study.

Role of Cardiac Anesthesiologists in Intraoperative Enhanced Recovery After Cardiac Surgery (ERACS) Protocol: A Retrospective Single-Center Study Analyzing Preliminary Results of a Yearlong ERACS Protocol Implementation

INTRODUCTION

Enhanced recovery after cardiac surgery (ERACS) has been gaining rapid acceptance after multiple studies have demonstrated promising results in improved outcomes of enhanced recovery after surgery in other surgical fields (eg, colorectal, orthopedic, thoracic, etc). Cardiac surgery has several unique challenges, including sternotomy, cardiopulmonary bypass and associated coagulopathy, blood transfusion, and postoperative intensive care requirement. Nonetheless, selective cardiac surgical patients can still benefit from ERACS. Guidelines for perioperative care in cardiac surgery, previously published by the ERACS Society, are weighted heavily in preoperative and postoperative management without much focus on intraoperative care provided by anesthesiologists. To address this gap and to explore anesthesiology's contribution in achieving ERACS, the study authors' cardiac anesthesiology division, in collaboration with cardiac surgery, introduced the ERACS protocol in their institution in February 2020.

METHODS

The cardiac anesthesiology division, in collaboration with cardiac surgery, introduced the ERACS protocol consisting of multimodal opioid-sparing analgesia, including the introduction of regional blocks, hemostasis management protocol, reversal of neuromuscular blockade, and administration of antiemetics in the authors' institution in February 2020. They have conducted a retrospective chart review study comparing patients who have received ERACS measures with a similar historic cohort who underwent cardiac surgery prior to initiation of an ERACS protocol. The primary outcomes of the study were to determine patients' time to extubation, postoperative opioid consumption, intensive care unit (ICU) length of stay (LOS), and incidence of postoperative complications (eg, postoperative nausea vomiting [PONV], bleeding, ICU readmission, delirium.

RESULTS

The ERACS patients showed reduced opioid consumption (intraoperative fentanyl; postoperative fentanyl, as well as oxycodone, in the first 6 hours postoperatively), lesser mechanical ventilation (2.5 hours less), shorter ICU stays (5 hours less), shorter hospital LOS (1 day), and lesser incidence of PONV. None of the ERACS patients required blood transfusion. The study authors performed an anonymous survey among the anesthesiologists and ICU providers to assess providers' satisfaction, which showed 92% of survey takers agreed that the ERACS protocol should be continued for future cardiac patients, and 61% of survey takers reported superior pain control in ERACS group of patients while managing those patients.

DISCUSSION

The ERACS is achievable after the careful implementation of a series of measures. It does not signify only fast-track extubation and opioid-sparing analgesia, and must be implemented in the entire perioperative period beginning from preoperative clinic to postoperative rehabilitation. Cardiac anesthesiologists play a vital role in execution of intraoperative ERACS measures. Both providers and patients themselves are key stakeholders. A larger randomized prospective trial is warranted to solidify the inference.

Pediatric Neurocritical Care: Maximizing Neurodevelopmental Outcomes Through Specialty Care

The field of pediatric neurocritical care (PNCC) has expanded and evolved over the last three decades. As mortality from pediatric critical care illness has declined, morbidity from neurodevelopmental disorders has expanded. PNCC clinicians have adopted a multidisciplinary approach to rapidly identify neurological injury, implement neuroprotective therapies, minimize secondary neurological insults, and establish transitions of care, all with the goal of improving neurocognitive outcomes for their patients. Although there are many aspects of PNCC and adult neurocritical care (NCC) medicine that are similar, elemental difference between adult and pediatric medicine has contributed to a divergent evolution of the respective fields. The low incidence of pediatric critical care illness, the heterogeneity of neurological insults, and the limited availability of resources all shape the need for a PNCC clinical care model that is distinct from the established paradigm adopted by the adult neurocritical care community at large. Considerations of neurodevelopment are fundamental in pediatrics. When neurological injury occurs in a child, the neurodevelopmental stage at the time of insult alters the impact of the neurological disease. Developmental variables contribute to a range of outcomes for seemingly similar injuries. Despite the relative infancy of the field of PNCC, early reports have shown that implementation of a specialized PNCC service elevates the quality and safety of care, promotes education and communication, and improves outcomes for children with acute neurological injuries. The multidisciplinary approach of PNCC clinicians and researchers also promotes a culture that emphasizes the importance of quality improvement and education initiatives, as well as development of and adherence to evidence-based guidelines and family-focused care models.

Effects of the response to the COVID-19 pandemic in chest trauma patients in China: a multicenter retrospective study

BACKGROUND

An international pandemic of severe coronavirus disease (COVID-19) has been caused by the novel coronavirus SARS-CoV-2. A large number of patients with chest trauma were infected with COVID-19. The COVID-19 pandemic had a significant impact on the management of chest trauma.

OBJECTIVE

The present observational study was conducted to evaluate the clinical characteristics and outcomes of chest trauma patients with or without COVID-19 infection.

METHODS

A multicenter observational study was performed at three Chinese hospitals between November 1, 2022, and January 31, 2023. All enrolled patients were diagnosed with chest trauma. We analyzed data from existing medical records, including all baseline data and prognostic follow-up data, such as 30-day mortality, hospital stays, hospitalization costs, and complications.

RESULTS

All 375 eligible patients completed the follow-up. There was no significant difference in baseline characteristics between chest trauma combined with COVID-19 (p > 0.05). Chest trauma combined with COVID-19 infection may lead to higher 30-day mortality (16.36% vs. 7.14%, p = 0.005), longer hospital stays (22.5 ± 5.9 vs. 12.8 ± 4.2, p < 0.001), larger hospitalization costs (p < 0.001), and increased hospitalization complications, such as pulmonary embolism (10.30% vs. 4.76%, p = 0.039), deep vein thrombosis (DVT, 33.33% vs. 18.57%, p = 0.001), the incidence of 7-day delirium (69.70% vs. 46.19%, p < 0.001), and respiratory failure (38.18% vs. 24.77%, p = 0.005).

CONCLUSIONS

Compared to chest trauma alone, it may lead to higher mortality, larger hospitalization costs, and more complications. To better respond to the future of COVID-19 or other similar virus-borne disease pandemics, it is important to understand the clinical characteristics and complications, such as pulmonary embolism, DVT, and respiratory failure after COVID-19 infection. To guide the future treatment of chest trauma combined with COVID-19 infection or other infectious diseases.

Protocol: dexmedetomidine on myocardial injury after noncardiac surgery-a multicenter, double-blind, controlled trial

AIMS

Myocardial injury after noncardiac surgery (MINS) is common in elderly patients and considered as an independent predictor of 30-day mortality after noncardiac surgery. Dexmedetomidine possesses cardiac-protective profile. Previous clinical studies have found that perioperative application of dexmedetomidine is associated with decreased 1-year mortality in patients undergoing cardiac surgery. The current study protocol aims to investigate the effects of dexmedetomidine on the incidence of MINS, complications, and 30-day mortality in elderly patients subjected to noncardiac surgery.

METHODS

A multicenter, randomized, controlled, double-blind, prospective trial is designed to explore cardiac protection of dexmedetomidine in the elderly patients undergoing noncardiac surgery. A total of 960 patients aged over 65 years will be recruited and randomly assigned to dexmedetomidine group (group Dex) and normal saline placebo group (group NS) in a ratio of 1:1. Patients in group Dex will receive a bolus dose of 0.5 μg/kg dexmedetomidine within 10 min before surgical incision, followed by a consistent infusion at the rate of 0.3-0.5 μg/kg/h throughout the operation. Group NS patients will receive the same volume of normal saline. The primary outcome is the incidence of MINS via detecting the hs-TnT level within 3 days after the operation. The secondary outcome includes myocardial ischemic symptoms, the incidence of major adverse cardiovascular events (MACE) in hospital, length of ICU and postoperative hospital stay, the incidence of inhospital complications, and 30-day all-cause mortality.

DISCUSSION

The results of the current study will illustrate the effect of dexmedetomidine on myocardial injury for elderly patients undergoing major noncardiac surgery.

TRIAL REGISTRATION

The trial was registered with Chinese Clinical Trial Registry (CHICTR) on Aug 24, 2021 (ChiCTR2100049946, http://www.chictr.org.cn/showproj.aspx?proj=131804 ).

Neurologic complications after cardiopulmonary bypass - A narrative review

Neurologic complications, associated with cardiac surgery and cardiopulmonary bypass (CPB) in adults, are common and can be devastating in some cases. This comprehensive review will not only consider the broad categories of stroke and neurocognitive dysfunction, but it also summarises other neurological complications associated with CPB, and it provides an update about risks, prevention and treatment. Where appropriate, we consider the impact of off-pump techniques upon our understanding of the contribution of CPB to adverse outcomes.

Taming Postoperative Delirium with Dexmedetomidine: A Review of the Therapeutic Agent's Neuroprotective Effects following Surgery

Postoperative delirium (POD) represents a perioperative neurocognitive disorder that has dreaded ramifications on a patient's recovery from surgery. Dexmedetomidine displays multiple mechanisms of neuroprotection to assist in preventing POD as a part of a comprehensive anesthetic care plan. This review will cover dexmedetomidine's pharmacological overlap with the current etiological theories behind POD along with pre-clinical and clinical studies on POD prevention with dexmedetomidine. While the body of evidence surrounding the use of dexmedetomidine for POD prevention still requires further development, promising evidence exists for the use of dexmedetomidine in select dosing and circumstances to enhance recovery from surgery.

Clinical observation of dexmedetomidine nasal spray in the treatment of sleep disorders on the first night after undergoing maxillofacial surgery: a single-center double-blind randomized controlled study

Purpose: Dexmedetomidine exerts a sedative effect by promoting the sleep pathway endogenously and producing a state similar to N2 sleep. This study aimed to study the efficacy and safety of dexmedetomidine nasal spray in the treatment of postoperative sleep disturbance. Methods: This study enrolled 120 participants [men and women; age, 18-40 years; American Society of Anesthesiologists grade, I or II] who underwent maxillofacial surgery under general anesthesia through nasotracheal intubation. The participants were randomly divided into three groups: blank control group (BC group), 1.0 μg/kg dexmedetomidine group (1.0 Dex group), and 1.5 μg/kg dexmedetomidine group (1.5 Dex group), with 40 patients allocated to each group. At 21:30 on the night after the operation, the intervention groups were administered their corresponding doses of dexmedetomidine nasal spray. The Pittsburgh Sleep Quality Index (PSQI) scale was used to evaluate the baseline sleep status of participants 1 month preoperatively and on the night after the operation. Polysomnography (PSG) was used to record the sleep status on the night after the operation. We recorded the rescue times of sedative and analgesic drugs on the first night after surgery, adverse reactions, total hospital stay duration, and total costs. Results: Compared with patients in the BC group, those in 1.0 Dex and 1.5 Dex groups had longer N2 sleep duration, were awake for a shorter time after dose administration, woke up less often, and had significantly improved sleep efficiency (p < 0.05). Compared with the BC group, the PSQI scores of 1.0 Dex and 1.5 Dex groups were significantly lower on the night after operation, and the proportion of PSQI > 5 was significantly lower (p < 0.05). Compared with patients in the BC group and the 1.0 Dex group, those in the 1.5 Dex group had significantly prolonged N3 sleep, reduced frequency of requiring sufentanil rescue, lower incidence of sore throat after surgery, and shorter average length of hospital stay (all, p < 0.05). Conclusion: The sleep quality of participants on the night after having undergone maxillofacial surgery was safely and effectively improved by 1.0-1.5 μg/kg dexmedetomidine atomized nasal sprays. Notably, only the latter could prolong N3 sleep. Level of Evidence II: Evidence was obtained from at least one properly designed randomized controlled trial.

Postoperative infusion of dexmedetomidine via intravenous patient-controlled analgesia for prevention of postoperative delirium in elderly patients undergoing surgery

BACKGROUND

Postoperative delirium (POD) is a common clinical complication in elderly patients after surgery and predicts poor outcomes.

AIM

We researched whether postoperative infusion of dexmedetomidine (DEX) had prophylactic effect on POD in elderly patients.

METHODS

A total of 236 patients over the age of 60 years undergoing thoracoabdominal tumor surgery were enrolled in Zhejiang Cancer Hospital from November 2016 to October 2020. The patients were randomly assigned into DEX group (group D) and control group (Group C). DEX was provided via PCIA pump 1-3 days after surgery, which consisted of 3 ug/kg sufentanil and 3 ug/kg DEX in group D, and 3 ug/kg sufentanil without DEX in group C. The PCIA parameters were programmed as follows: total amount 150 ml, 2 ml bolus dose with a lock-out of 10 min and background infusion rate 2 ml/h. The primary endpoint was the incidence of POD, assessed twice daily within 7 days after surgery by Richmond Agitation-Sedation Scale (RASS) and the Confusion Assessment Method-Intensive Care Unit (CAM-ICU). The secondary endpoint was postoperative hospitalization days, ICU stay time, adverse events and non-delirium complications.

RESULTS

The incidence of POD in all patients was 7%. The incidence of POD in group C was significantly higher than that in group D (10.1% vs 3.4%, P = 0.042). There were no significant differences in length of hospital stay after operation, ICU stay time, the percentage of patients discharged within 7 days after surgery, non-delirium complications, and 30-day all-cause deaths between the two groups. The incidence of hypertension in group D was lower than that in group C (P = 0.003), and there were no differences in other adverse events.

CONCLUSION

Patients aged over 60 years received DEX in addition to intravenous patient-controlled analgesia (PCIA) for major thoracoabdominal surgery experienced less delirium.

Critical care for patients with substance use disorders

PURPOSE OF REVIEW

To examine the impact of substance use disorders (SUDs) on critical illness and the role of critical care providers in treating SUDs. We discuss emerging evidence supporting hospital-based addiction treatment and highlight the clinical and research innovations needed to elevate the standards of care for patients with SUDs in the intensive care unit (ICU) amidst staggering individual and public health consequences.

RECENT FINDINGS

Despite the rapid increase of SUDs in recent years, with growing implications for critical care, dedicated studies focused on ICU patients with SUDs remain scant. Available data demonstrate SUDs are major risk factors for the development and severity of critical illness and are associated with poor outcomes. ICU patients with SUDs experience mutually reinforcing effects of substance withdrawal and pain, which amplify risks and consequences of delirium, and complicate management of comorbid conditions. Hospital-based addiction treatment can dramatically improve the health outcomes of hospitalized patients with SUDs and should begin in the ICU.

SUMMARY

SUDs have a significant impact on critical illness and post-ICU outcomes. High-quality cohort and treatment studies designed specifically for ICU patients with SUDs are needed to define best practices and improve health outcomes in this vulnerable population.

Benzodiazepines and postoperative delirium: should we be as cautious as we are?

A recent systematic review and meta-analysis by Wang and colleagues in the British Journal of Anaesthesia calls into question the concept that perioperative benzodiazepine administration is associated with development of postoperative delirium in older individuals after anaesthesia and surgery. This editorial focuses on potential bias within the systematic review and addresses major concerns surrounding benzodiazepine use in the older perioperative population.

Sleep and Perivascular Spaces

PURPOSE OF REVIEW

The glymphatic system is hypothesized to act as the brain's filtration system to remove toxic solutes that accumulate throughout the day. Perivascular spaces (PVSs) play a fundamental role in the ability of the glymphatic system to function, and sleep influences the effectiveness of this system. This article reviews the complexity of the interplay between sleep, the glymphatic system, and PVS.

RECENT FINDINGS

New imaging techniques have illuminated the structure of PVS and their associations with differing disease states. Research has shown that sleep may play a key role in the function of PVS and the influence of adenosine, astrocyte, and aquaporin-4 channel in the function of the glymphatic system. Emerging data suggest that differing pathological states such as neuroinflammatory conditions, neurodegenerative diseases, and cognitive dysfunction may be associated with underlying glymphatic system dysfunction, and sleep disorders could be a potential intervention target.