Aims/Background Subsyndromal delirium (SSD) in elderly patients can lead to prolonged hospital stays, reduced quality of life, and cognitive decline. Evidence suggests that nursing interventions play a key role in mitigating SSD risk by facilitating early identification as well as timely and effective interventions. This study aimed to assess the knowledge, attitude, and practice (KAP) levels of nurses in primary hospitals regarding elderly SSD, identify factors influencing these levels, and construct a network-based tiered training program. Methods A literature review and Delphi expert consultation method, based on the KAP theory, were utilized to develop a questionnaire to assess the KAP levels of nurses regarding elderly SSD in primary hospitals. A pilot study was conducted to determine the reliability and validity of the questionnaire. From January 2024 to June 2024, a stratified cluster sampling method was employed to survey nurses from six secondary or higher-level primary hospitals in Shaoxing, China. The self-developed questionnaire was used to evaluate the KAP levels of primary hospital nurses regarding elderly SSD assessment and analyze factors influencing their scores. Based on the findings, a network-based tiered training program was constructed. Results A total of 615 questionnaires were distributed, of which 600 were valid, with an effective response rate of 97.56%. The mean total KAP score for nurses in primary hospitals regarding elderly SSD assessment was 98.11 ± 12.23, with an overall scoring rate of 61.32%. The mean scoring rates for KAP were 48.35%, 81.29%, and 68.84% respectively. Significant differences in KAP scores regarding elderly SSD for nurses in primary hospitals with different characteristics were observed based on age, educational level, years of experience, and professional title (p < 0.001). Multiple linear regression analysis showed that years of experience and professional title (nurse in charge or deputy senior nurse practitioner and above) were significant predictors of total KAP scores (p < 0.05). Conclusion The overall KAP level of primary hospital nurses regarding elderly SSD assessment was suboptimal. While attitudes towards SSD were generally positive, knowledge and practice levels required considerable improvement. A network-based tiered training program was developed to enhance the capacity of primary hospital nurses for timely and accurate identification of SSD risks in elderly patients.

Postoperative delirium (POD), emergence delirium (ED), and postoperative cognitive dysfunction (POCD) are disorders of the neuropsychiatric spectrum affecting the elderly during the postoperative period, potentially sharing a common pathophysiological pathway. Disrupted sleep postoperatively correlates with both POD and POCD, revealing overlapping risk factors. This study investigates the potential of dexmedetomidine anesthesia to reduce the incidence of POD (primary outcome), ED, POCD, impairment of sleep quality, and emergent chronic pain (secondary outcomes) in older adults undergoing major orthopedic surgery under regional anesthesia.

In this double-blind randomized control trial, patients scheduled for major lower limb orthopedic surgery under regional anesthesia were randomized to receive either dexmedetomidine or propofol for sedation at a 1:1 ratio. POD, ED, and POCD were assessed with the Confusion Assessment Method tool, the Riker Sedation-Agitation scale, and the European Battery of psychometric tests, respectively. Sleep quality was assessed using the Pittsburg Sleep Quality Index and chronic pain with the painDETECT tool. Assessments of all outcome variables were performed before surgery, and at 48 hours and 3 months postoperatively.

A total of 80 patients (dexmedetomidine group n = 41) were enrolled in the study and completed the follow-up. POD, ED, and early POCD incidence were significantly lower in dexmedetomidine compared to propofol group (4.8% vs 38.4%, P = .001; 2.4% vs 38.4%, P < .001; 2.4% vs 56.4%, P < .001, respectively). Patients in the dexmedetomidine group reported improved sleep quality in the immediate postoperative period (lower PSQI score) and lower painDETECT scores at 3 months (4.4 ± 0.7 vs 13.4 ± 0.8, P < .001; 2.4 ± 0.9 vs 5.3 ± 0.9, P = .023, respectively). Intraoperative bradycardia and hemodynamic instability episodes were more common in the dexmedetomidine group while a single patient presented airway obstruction (2.4% vs 30.8%, P = .002) in the dexmedetomidine group.

Sedation with dexmedetomidine resulted in a statistically and clinically important reduction in the incidence of POD, ED, and early POCD, while it improved self-reported postoperative sleep quality and reduced chronic pain scores in patients undergoing major elective lower limb surgery under regional anesthesia.

With an estimated 2.1 million hip and knee replacements performed annually in developed countries, orthopedic surgeries can result in complications such as postoperative pain and cognitive dysfunctions. Dexmedetomidine shows potential for reducing pain and opioid use and improving cognitive outcomes, but its efficacy in orthopedic settings needs further evaluation.

A comprehensive literature search was performed across electronic databases (e.g., PubMed) up to 1 June 2024 to identify relevant randomized controlled trials (RCTs) investigating the use of dexmedetomidine for orthopedic surgeries. The primary outcomes included visual analog scale (VAS), opioid consumption, incidence of postoperative cognitive dysfunction (POCD), and postoperative delirium (POD). Meta-analysis was conducted using RevMan 5.3 and Stata 16.0, with statistical significance set at P < 0.05. Sensitivity analyses, along with trial sequential analysis (TSA), were used to evaluate the robustness of the findings.

The meta-analysis included 59 RCTs with 7713 participants and demonstrated that dexmedetomidine significantly reduced postoperative VAS score (mean difference [MD] -0.50, P = 0.0003) and opioid consumption (MD -11.91, P < 0.0001) and decreased the incidence of POCD (risk ratio [RR] 0.59, P = 0.006) and POD (RR 0.49, P < 0.0001). Dexmedetomidine also prolonged motor (MD: 1.70, P < 0.0001) and sensory block durations (MD: 1.80, P < 0.0001) and delayed the time to first rescue analgesics (MD: 1.51, P < 0.0001). TSA and sensitivity analysis confirmed the robustness and reliability of the results, whereas meta-regression revealed no significant effect of variables on primary outcomes.

Our study demonstrates that intravenous dexmedetomidine significantly improved postoperative pain and neurocognitive functions in orthopedic surgery patients.

To date, studies assessing the relationship between intensive care unit acquired weakness (ICU-AW) and postoperative delirium (POD), two of the most common complications in the intensive care unit (ICU), are lacking.

To explore the association of the occurrence of POD, POD subtypes and POD duration with ICU-AW in a surgical intensive care unit (SICU).

This study was a prospective observational study. Four hundred and two postoperative patients in a SICU at a tertiary hospital in Shanghai, China, participated in the study. Data were collected through the electronic medical record system of the hospital between October 2022 and July 2023. POD was assessed using the Richmond agitation-sedation scale (RASS) and the Confusion Assessment Method for the intensive care unit (CAM-ICU). The Medical Research Council score (MRC score) was used to measure ICU-AW. The bivariate logistic regression analysis was used to analyse the relationship between ICU-AW and POD, and further, the influencing factors of ICU-AW.

Of the 402 analysed patients (mean age: 69.2 ± 14.84, 59.7% male), 121 (30.10%) patients developed ICU-AW, and 92 (22.89%) patients developed POD. Of the ICU-AW group, 53 (43.80%) patients screened positive for POD. The occurrence of POD (odds ratio (OR), 0.227 95% CI: 0.052-0.981), hypoactive POD (OR, 4.241 95% CI: 1.490-12.072) and POD duration (OR, 2.649; 95% CI: 1.422-4.935) were independently associated with ICU-AW. Moreover, diabetes (OR, 1.710; 95% CI: 1.036-2.823) and Interleukin-6 (IL-6) (OR, 1.001; 95% CI: 1.000-1.001) were also significantly correlated with ICU-AW.

ICU-AW was associated with POD, POD subtypes and POD duration in the SICU patients. Screening for hypoactive POD should be used as part of routine risk assessment in the SICU focused on identifying ICU-AW and specifying a timely and targeted plan during the early stages of the postoperative period.

While closely monitoring ICU patients with high IL-6 levels and diabetes, nurses should assess the type and duration of POD in patients and implement care interventions to prevent the development of ICU-AW.

In recent years, many pharmacological agents for the prevention of delirium have emerged; however, the efficacy of these agents in preventing delirium remains unclear.

To compare and rank the efficacy of different pharmacological interventions for the prevention of delirium.

A systematic review and network meta-analysis.

Relevant randomized controlled trials on drug prevention of delirium were extracted from three electronic databases. A network meta-analysis was then conducted to assess the relative efficacy of drug interventions in preventing delirium. The quality of the data was evaluated using the Cochrane Risk of Bias tool.

A total of 80 randomized controlled trials on drug interventions were included in the final analysis. Treatment with dexmedetomidine can prevent delirium.

Dexmedetomidine treatment can prevent delirium and reduce patient suffering. Healthcare professionals should be encouraged to use dexmedetomidine for delirium prevention.

Remimazolam is a novel short-acting benzodiazepine. This study compared the effects of remimazolam and propofol on cognitive function in adult patients after surgery or other procedures.

We searched electronic databases, including PubMed, Embase, CENTRAL, Web of Science, and Scopus, for relevant studies. The primary outcome was the proportion of participants who experienced delirium or impaired cognitive function postoperatively. Secondary outcomes included the incidence of hypotension, bradycardia, and postoperative nausea and vomiting. We estimated the odds ratios (OR) and mean differences (MD) with 95% CIs using a random-effects model.

In total, 1295 patients from 11 randomized controlled trials were included. The incidence of postoperative delirium was 8.0% in the remimazolam group and 10.4% in the propofol group that was not significantly different (OR: 0.74, 95% CI [0.39-1.42], P = 0.369, I2 = 32%). More favorable cognitive function, as assessed using the Mini-Mental State Examination, was observed in the remimazolam group compared to the propofol group (MD: 1.06, 95% CI [0.32-1.80], P = 0.005, I2 = 89%). Remimazolam lowered the incidence of hypotension (OR: 0.28, 95% CI [0.21-0.37], P = 0.000, I2 = 0%) compared to propofol.

Remimazolam did not increase the risk of postoperative delirium and maintained cognitive function well, providing hemodynamic stability during surgery compared to propofol.

Propofol, a commonly used anesthetic, is known to cause postoperative cognitive dysfunction (POCD), particularly after prolonged or high-dose administration. Its effects on neural remodeling in the hippocampal region, which is vital for cognitive function, remain poorly understood. This study employs single-cell RNA sequencing (scRNA-seq) and high-throughput transcriptomic analysis to elucidate the molecular mechanisms by which propofol impairs hippocampal neural remodeling. Our findings indicate that propofol suppresses the (5-Hydroxytryptamine Receptor 1A/Glutamate Receptor 2/Phosphoinositide 3-Kinase Regulatory Subunit 1) HTR1A/GRIA2/PIK3R1 signaling pathway, contributing to cognitive dysfunction in mice. In vitro experiments reveal that propofol treatment reduces the expression of HTR1A/GRIA2/PIK3R1-related factors, decreases neuronal activity and synaptic plasticity, and increases apoptosis and inflammation. In vivo experiments demonstrate significant impairments in spatial memory and learning abilities in mice treated with propofol. These results provide new insights into the long-term effects of anesthetic drugs and offer a scientific basis for their judicious use in clinical practice. The study highlights potential strategies and targets for preventing and treating POCD, emphasizing the importance of understanding the molecular mechanisms underlying anesthetic-induced cognitive dysfunction.

This article explored the application of dexmedetomidine (Dex), a highly selective alpha-2 agonist, in managing postoperative cognitive dysfunction (POCD) in elderly patients undergoing radical colon cancer surgery. Aging is associated with a progressive decline in physiological functions and an increased risk of adverse surgical outcomes, including POCD, which encompasses many neurocognitive disorders that manifest during the perioperative period. The aging population is at a higher risk for POCD, which can lead to prolonged hospital stays, delayed recovery, and increased healthcare costs. Dex has neuroprotective, opioid-sparing, and sympatholytic properties, which reduces the incidence and severity of POCD. Dex was introduced for sedation in patients receiving mechanical ventilation but has since been adopted in anesthesia due to its multifaceted benefits. Its application extends to sedation, analgesia, maintenance of anesthesia, and controlling delirium. Its neuroprotective and anti-inflammatory effects have been explored in managing POCD. This article discussed the broad range of patient and procedure-related risk factors for POCD. Early identification and intervention are crucial to prevent the progression of POCD, which can have severe physical, psychological, and economic consequences. The article underscored the importance of a multidisciplinary approach in managing POCD, involving the optimization of comorbidities, depth of anesthesia monitoring, hemodynamic stability, and cerebral oxygenation monitoring.

Postoperative neurocognitive disorders (PND) represent a significant challenge affecting patients undergoing surgical procedures, particularly in the elderly population. These disorders can lead to profound impairments in cognitive function, impacting memory, attention, and overall quality of life. Despite ongoing research efforts to identify risk factors and improve management strategies, PND remains underdiagnosed and poorly understood, complicating postoperative recovery and rehabilitation. This review aims to explore the recent advancement in the literature about PND, focusing on the underlying mechanisms, risk factors, and potential therapeutic approaches. We highlight recent advancements in the understanding of neuroinflammation, and it is implications for novel therapies to prevent PND. By synthesizing the latest research, we hope to provide insights that could lead to improved outcomes for patients at risk for PND and foster a shift towards more effective preventive measures in such population.

This study aims to analyze the global trends and current status of perioperative cognitive function protection for preventing postoperative delirium(PCFP-POD), as well as to predict research hotspots.

We conducted a literature search on the Web of Science Core Collection (WoSCC) and selected articles published between January 1, 2014, and December 31, 2023, related to PCFP-POD. The retrieved data were subjected to bibliometric analysis and visualization using CiteSpace 6.2.R4, VOSviewer 1.6.20 software, and the Bibliometrics website.

A total of 355 articles published between 2014 and 2023 were retrieved from the online databases. The number of publications on perioperative cognitive function protection for preventing postoperative delirium sharply increased from 2018 onwards. Key themes included drug and non-drug interventions, postoperative cognitive dysfunction in cardiac and hip surgery, and the effects of anesthetic drugs. High-frequency keywords included postoperative delirium, intervention, postoperative cognitive impairment, and cognitive training.

The number of research articles on PCFP-POD increased significantly from 2014 to 2023. Future research trends may focus on cognitive function protection related to surgical categories, anesthesia methods, electroencephalogram monitoring, and nursing care.

Previous studies have shown that perioperative use of adjuvants, such as the alpha-2 agonist dexmedetomidine, may reduce postoperative pain and opioid requirements. However, information about optimal dosing is lacking. We investigated if premedication with intranasal dexmedetomidine compared with placebo reduces postoperative pain in patients undergoing total knee arthroplasty under spinal anaesthesia.

This single-centre, double-blind, two-arm study compared premedication with intranasal dexmedetomidine (single 1 μg kg-1 dose) to intranasal saline in 101 consecutive elective patients undergoing total knee arthroplasty under spinal anaesthesia. The primary outcome was postoperative pain measured with the numerical rating scale during the first 24 h. Secondary outcomes were postoperative opioid requirement, perioperative haemodynamic variables, requirement of additional intraoperative sedation, incidence of postoperative nausea and vomiting, and patient satisfaction at 30 days after surgery.

Patients in the dexmedetomidine group had lower numerical rating scale scores [median (interquartile range) 2.0 (0.0-3.0)] at 3 h when compared with the control group [3.0 (2.0-4.0)] (P=0.037). Cumulative 24 h opioid requirements (in morphine equivalents) did not differ between dexmedetomidine [45 mg (30-68 mg)] and control groups [53 mg (38-88 mg)] (P=0.334). More patients in the dexmedetomidine group were satisfied with pain management in the ward (P=0.0013). The groups did not differ in the incidence of postoperative nausea and vomiting (P=0.310) or haemodynamic adverse events (P>0.27 for all).

Our results indicate that intranasal dexmedetomidine may reduce postoperative pain and the requirement for additional sedation and increase short-term patient satisfaction in patients undergoing total knee arthroplasty.

ClinicalTrials.gov (NCT04859283).

Anesthesia has been thought to impact cognitive function in the elderly, although the exact pathophysiology remains uncertain. This systematic review aimed to analyze the impact of ketamine and propofol on cognitive function in elderly patients. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted across PubMed/Medline, Cochrane Central Register of Controlled Trials (CENTRAL), Europe PMC, ScienceDirect, ClinicalTrials.gov, and EBSCO Open Dissertations on November 17, 2024. After screening, the methodological quality of the included studies was assessed using the Cochrane Risk-of-Bias-2 Tool and the Newcastle Ottawa Scale. Studies were included if they focused on patients aged 60 and older, encompassing 3,149 participants across 19 studies, predominantly randomized controlled trials. Key outcomes assessed included postoperative cognitive dysfunction (POCD) and postoperative delirium (POD). Results indicated that many studies found no significant differences in cognitive outcomes between certain anesthetic drugs. However, ketamine was likely associated with an increased risk of POCD, similar to propofol, when compared to remimazolam and dexmedetomidine. Notably, ketofol reduced POD incidence compared to placebo, while higher propofol doses were linked to an increased incidence, and severity of hypoactive POD. The most evident finding was that propofol attenuated POCD compared to inhaled anesthetic agents. Given this, it is crucial for clinicians to carefully consider anesthetic choices for elderly patients. Future research should focus on larger multicenter trials to further validate these results and explore the long-term cognitive effects of various anesthetic agents.

Intertrochanteric femoral fracture (IFF) is a public issue in the old. Combined spinal-epidural anesthesia (CSEA) is commonly utilized for lower limb orthopedic surgery in elderly patients. Therefore, this study explored the application of dexmedetomidine (Dex) and ropivacaine (Rop) assisted CSEA in elderly IFF patients.

Totally 187 elderly IFF patients were assigned into the Rop assisted CSEA (Rop-CSEA), low-dose Dex-Rop assisted CSEA (low Dex and Rop-CSEA) and high-dose Dex-Rop assisted CSEA (high Dex and Rop-CSEA) groups. We compared block effects, hemodynamic indicators [heart rate (HR)/respiratory rate (RR)/mean arterial pressure (MAP)] at time before anesthesia (T0)/skin incision (T1)/10 min postoperatively (T2)/suture postoperatively (T3)/anesthesia recovery (T4), postoperative pain mediator release [substance P (SP)/prostaglandin E2 (PGE2)/5-hydroxytryptamine (5-HT)], neutrophil-lymphocyte ratio (NLR), adverse reactions, delirium and cognitive dysfunction incidence.

Compared with the Rop-CSEA group, low/high Dex and Rop-CSEA groups had shortened onset times, prolonged recovery times in sensory/motor block, elevated HR/RR/MAP, repressed pain mediator release, and reduced postoperative delirium and cognitive dysfunction incidences. HR/RR/MAP exhibited reductions followed by elevations at T2-T4, and SP/PGE2/5-HT levels revealed elevations in all groups postoperatively. NLR level displayed enhancement followed by reduction, and NLR in the low/high Dex and Rop-CSEA groups was abated on postoperative days 1-5. Total incidence of adverse reactions in the high Dex and Rop-CSEA group was enhanced.

Dex and Rop assisted CSEA shortens the onset time of anesthesia, maintains perioperative hemodynamic stability, inhibits pain mediator release, reduces postoperative NLR level and the incidence of delirium and cognitive dysfunction in IFF patients.

Dexmedetomidine effectively prevents emergence delirium in children. However, intravenous dexmedetomidine is frequently associated with hemodynamic instability and delayed recovery. Intranasal dexmedetomidine has been proposed as a method of reducing these side effects. This study aimed to evaluate the effects of intranasal versus intravenous dexmedetomidine on emergence recovery and hemodynamics in children undergoing adenotonsillectomy.

A total of 139 children, aged 3-10 years, who were scheduled for elective adenotonsillectomy were randomly assigned to receive intravenous dexmedetomidine (IV DEX group) or intranasal dexmedetomidine (IN DEX group), or saline (control group) after anesthesia induction. The primary outcome was the highest score on the pediatric anesthesia emergence delirium (PAED) score during the first 30 min after awakening. Secondary outcomes included the perioperative blood pressure and heart rate, time to awakening, postoperative pain score, and length of post-anesthesia care unit (PACU) stay.

The highest PAED and pain scores were significantly lower in the IV and IN DEX groups than those in the control group during the first 30 min after awakening. However, no significant differences were observed between the IV and IN DEX groups. Notably, patients in the IN DEX group exhibited a significantly lower PAED score at 2 h and lower pain scores at 2, 4, and 6 h postoperatively than those in the IV DEX group. Patients in the IV DEX group exhibited a significantly longer awakening time and length of PACU stay than those in the IN DEX and control groups. In the IV DEX group, the heart rate was significantly lower perioperatively than at baseline, while this effect was not observed in the IN DEX group.

Both intravenous and intranasal administration of dexmedetomidine after induction of anesthesia effectively improved emergence delirium and pain intensity in children undergoing adenotonsillectomy. Intranasal administration of dexmedetomidine provided more stable hemodynamics and more prolonged analgesia and sedation than intravenous infusion of dexmedetomidine.

https://www.chictr.org.cn/showproj.html?proj=180658.

We conducted a meta-analysis to investigate the effect of dexmedetomidine on postoperative delirium in elderly orthopedic surgery patients.

A meta-analysis was conducted to identify randomized controlled trials of dexmedetomidine in elderly patients undergoing orthopedic surgery. The data was published on October 25, 2024. PubMed, Embase, and Cochrane Library databases were searched. Outcome measures included incidence of delirium, length of hospital stay, visual analogue scale, and postoperative complications. Estimates are expressed as relative risk (RR) or mean difference (MD) with a 95% confidence interval (CI). The publications were reviewed according to the guidelines of the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

This study was registered with INPLASY (number INPLASY2024110004). A total of 3159 patients were included in 9 randomized controlled trials. The results showed that dexmedetomidine exhibited a preventive effect on delirium compared with the control group in elderly patients after orthopedic surgery (RR: 0.55, 95% CI: 0.45-0.66, P < 0.01, I2 = 0%). Subgroup analysis suggested that dexmedetomidine was significantly different from saline(RR: 0.56; 95% CI: 0.44-0.73, P<0.01, I²=31%) and propofol(RR: 0.52; 95% CI: 0.39-0.70, P<0.01, I²=0%) in reducing postoperative delirium in elderly fracture patients. No statistically significant differences were observed in length of hospital stay, visual analogue scale, and postoperative complications (P > 0.05). Certainty of evidence for postoperative delirium was moderate.

Dexmedetomidine has been shown to have a protective effect on postoperative delirium in elderly patients following orthopedic surgery.

Administration of cholinesterase inhibitors in combination with anticholinergic drugs for reversal of neuromuscular blocks may precipitate delirium through impairment of central cholinergic transmission, which could be avoided by using sugammadex. Therefore, we tested the primary hypothesis that postoperative delirium is less common when neuromuscular block is reversed with sugammadex than with neostigmine combined with glycopyrrolate or atropine.

We conducted a single-center retrospective cohort study, analyzing all adult patients having general anesthesia for noncardiac surgery who received neostigmine or sugammadex from January 2016 to March 2022. Inverse propensity score weighting and propensity score calibration were used to adjust for appropriate confounders. Our primary outcome was presence of delirium within the first 4 days after surgery, defined as at least 1 positive brief Confusion Assessment Method (bCAM) screening. The secondary outcome was the presence of early delirium within 24 hours of surgery.

Among 49,468 cases in our analysis, 6881 received sugammadex and 42,587 received neostigmine. After propensity weighting, the incidence of delirium was 1.09% in the sugammadex group and 0.82% in the neostigmine group. The odds of postoperative delirium did not differ between the sugammadex and neostigmine groups, with an estimated odds ratio (95% confidence interval) of 1.33 (0.91-1.95), P = .147. A sensitivity analysis restricted to only include cases with at least 6 bCAM measurements over postoperative day (POD) 1 to 4 had consistent results, as sugammadex compared with neostigmine was associated with an estimated odds ratio for postoperative delirium of 1.20 (0.82-1.77), P = .346. Sugammadex was significantly associated with an increased incidence of early postoperative delirium, with an estimated odds ratio of 1.71 (1.07-2.72), P = .025. Further analysis showed no treatment-by-age interaction for either postoperative delirium ( P = .637) or postoperative early delirium ( P = .904).

Compared to neostigmine, use of sugammadex for reversal of neuromuscular block was not associated with an increased risk of postoperative delirium in this retrospective single-center study. Though sugammadex was associated with a statistically significant increased risk of postoperative early delirium, the difference was small and not clinically relevant, and may reflect the presence of unknown confounders.

Dexmedetomidine (DexM), a highly selective α2-adrenoceptor agonist, significantly reduces postoperative adverse effects, including sleep and circadian rhythm disruptions. Vasoactive intestinal peptide neurons in the suprachiasmatic nucleus (SCNVIP) regulate the synchronization of circadian rhythms with the external environment in mammals. We investigate the effects of DexM on sleep and circadian rhythms, as well as the underlying mechanisms. Using electrophysiological and chemogenetic methods, along with locomotor activity and electroencephalogram/electromyogram recordings, we found that DexM accelerates the rate of re-entrainment following an 8-hour phase advance in the 12-hour light:12-hour dark cycle, increases the amount of non-rapid eye movement sleep, and decreases the mean duration of rapid eye movement sleep. Chemogenetic inhibition of SCNVIP neurons hinders the acceleration of re-entrainment and the changes in the sleep-wakefulness cycle induced by DexM. Electrophysiological results show that DexM increases the firing rate and the frequency of spontaneous glutamatergic postsynaptic currents while decreasing the frequency of spontaneous GABAergic PSCs in SCNVIP neurons through the α2-adrenergic receptor. Additionally, DexM reduces the frequency of miniature GABAergic PSCs in SCNVIP neurons. In conclusion, these findings suggest that DexM promotes sleep and maintains the coordination of circadian rhythms with the external environment by activating SCNVIP neurons through the α2-adrenoceptor.

Dexmedetomidine has received increasing attention for its sedative, analgesic, anxiolytic, anti-inflammatory and anti-stress effects in perioperative medicine. Numerous studies have been carried out to explore its influence on perioperative patients.

This study aimed to identify the most influential literature, trends and hotspots in dexmedetomidine research by bibliometric analysis.

Articles and reviews related to dexmedetomidine in perioperative medicine were collected from Web of Science Core Collection. VOSviewer and Citespace software were used for bibliometric analysis and data visualization.

A total of 1652 suitable publications were extracted from the database for analysis, including 1,497 articles and 155 reviews. The number of publications in the field of dexmedetomidine research has increased markedly since 2013, with China being the major contributor, followed by United States. BMC Anesthesiology published the highest number of papers on this topic. Anesthesiology ranked first in terms of average citations per paper and co-citation journal. Ji Fuhai was the most prolific author, and Ma Daqing was the most cited authors. The main hotspots during this period were "elderly patients", "postoperative cognitive dysfunction", "injury" and "risk factors".

This study presents an overview of the development related to dexmedetomidine in perioperative medicine using bibliometric analysis. Dexmedetomidine research is thriving and expanding rapidly around the world. The effect of dexmedetomidine on cognitive function has been the latest research hotspot. To advance research in this field, more rigorous and scientific multi-center studies should be designed and further cooperation and academic exchange should be strengthened.

Postoperative delirium (POD) is a common complication that has important implications for surgical patients, often leading to both short- and long-term cognitive deficits, worse outcomes, and increased healthcare costs. Given these implications, there may be a benefit in reducing the incidence of POD. Pharmacologic interventions may have the potential to reduce the risk of a patient developing POD.

Recently studied therapies include dexmedetomidine, propofol, haloperidol, ketamine, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, acetaminophen, melatonin/ramelteon, corticosteroids, midazolam, physostigmine, and neostigmine. In addition, the implementation of regional anesthesia and reduction of overall anesthetic depth have been examined. Of these therapies, dexmedetomidine has been studied the most and has the most supporting evidence for prevention of POD, but current studies lack clarity on optimal dosing and timing of dexmedetomidine administration. Acetaminophen, corticosteroids, and melatonin/ramelteon are other plausible medications that have potential for reducing POD incidence, but they all require further investigation. Reduction of anesthetic depth and regional anesthetics are options for anesthetic management that show promise but still lack enough supporting evidence in recent literature to receive a strong recommendation. Future research should focus on identifying optimal strategies for the implementation of the pharmacological options listed, including doses and timing of administration. Attention should be given to dexmedetomidine given its promise demonstrated by recent literature.

Remimazolam is often used for perioperative sedation due to its rapid onset and offset. However, the possible association between remimazolam and postoperative delirium (POD) remains undetermined. The present study evaluated whether remimazolam increased the incidence of POD compared with dexmedetomidine in elderly patients undergoing orthopedic surgery of the lower extremities.

This retrospective study included patients aged ≥ 65 years who had undergone orthopedic surgery of the lower extremities under spinal anesthesia from January 2020 to November 2022 and were sedated with continuous intravenous infusion of dexmedetomidine or remimazolam. The incidence of POD was assessed through a validated comprehensive review process of each patient's medical records. The effect of remimazolam on the occurrence of POD compared with dexmedetomidine was evaluated by propensity score weighted multivariable logistic models.

A total of 447 patients were included in the final analysis. The crude incidence of POD within 3 days after surgery was 7.5% (17/226) in the dexmedetomidine group and 11.8% (26/221) in the remimazolam group, increasing to 9.7% (22/226) and 15.8% (35/221), respectively (p = 0.073), within 5 days. The multivariable models showed that, compared with dexmedetomidine, intraoperative sedation with remimazolam significantly increased the occurrence of POD within 3 days (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.31 to 3.82, p = 0.003) and 5 days (OR 2.10, 95% CI 1.32 to 3.40, p = 0.002).

Compared with dexmedetomidine, remimazolam infusion may be associated with a higher risk of POD in elderly patients undergoing orthopedic surgery of the lower extremities under spinal anesthesia.

Postoperative cognitive dysfunction (POCD) is a common complication after surgery in elderly patients, and its prevalence can be up to 25.6% at one week after noncardiac surgery. This study mainly evaluates the combined effects of esketamine and dexmedetomidine on the incidence of POCD in elderly patients undergoing lumbar spine surgery and explores the underlying mechanisms.

A total of 162 elderly patients undergoing lumbar spine surgery were randomized into three groups: esketamine combined with dexmedetomidine group (ED group), esketamine group (E group), and dexmedetomidine group (D group). Primary outcome measures included the incidence of POCD on the first postoperative day. Secondary outcomes included the incidence of POCD on the third postoperative day, first postoperative day serum levels of neuron-specific enolase (NSE) and calcium-binding protein β (S100β), patient visual analog scale (VAS) scores at 2, 24, and 48 hours postoperatively, and the incidence of adverse events.

The incidence of POCD on the first postoperative day was significantly lower in the ED group compared to the E group (P = 0.017), with no significant differences when compared to the D group (P = 0.064). The levels of serum NSE in patients in the ED group on the first postoperative day were significantly lower than those in E group and D group (ED group vs E group, P = 0.028; ED group vs D group, P = 0.048). The results for the S100β were similar to those for the NSE (ED group vs E group, P = 0.005; ED group vs D group, P = 0.011).

The combination of esketamine and dexmedetomidine effectively reduces the incidence of POCD on the first postoperative day in elderly patients undergoing lumbar spine surgery.

Spinal anesthesia for transurethral resection of the prostate (TURP) has a short duration, which poses challenges for postoperative pain management. The present study aimed to investigate the effects of intravenous (IV) dexmedetomidine at a dosage of 0.4 µg/kg in prolonging the duration of spinal anesthesia and minimizing postoperative pain in elderly patients undergoing TURP.

This prospective randomized controlled trial enrolled 38 patients aged 60-80 years who underwent elective TURP with spinal anesthesia. The patients were randomly assigned to two treatment groups: Group D received IV 0.4 µg/kg dexmedetomidine, whereas Group C received IV normal saline after spinal anesthesia administration. The primary outcome was the time to 2-dermatome regression.

The 2-dermatome regression time was longer in Group D than in Group C (104.44 ± 16.97 min vs. 80.63 ± 15.59 min, p < 0.05). The peak sensory block levels were significantly higher in Group D [T7 (T6-T8)] than in Group C [T10 (T7-T10)] (p = 0.017). The incidence of hypotension and bradycardia and postoperative pain at 0, 6, 12, and 24 h were not different between two groups.

Intravenous dexmedetomidine at a dosage of 0.4 µg/kg significantly prolongs the duration of spinal sensory blockade. Although postoperative analgesia was not different, it provided hemodynamic stability without increasing the side effects.

To investigate the impact of surgical intervention on hemodynamic parameters and postoperative delirium in Stanford Type A aortic dissection patients.

A retrospective analysis was conducted on 139 patients who underwent surgery for Stanford Type A aortic dissection from February 2022 to February 2024. Hemodynamic parameters, including maximum ascending aortic diameter (MAAD), left ventricular end-diastolic diameter (LVEDd), and ejection fraction (LVEF), were compared pre- and post-surgery. Patients were divided into two groups based on delirium occurrence postoperatively: Group A (n=49, with delirium) and Group B (n=90, without delirium). Differences in surgical factors and intensive care conditions were analyzed, and risk factors for postoperative delirium were identified. Group sizes differ due to retrospective categorization based on observed outcomes rather than controlled sampling.

① Hemodynamic parameters: Postoperative MAAD and LVEDd were significantly reduced, while LVEF increased compared to preoperative levels (P < 0.05). ② Surgical and postoperative conditions: Group A had longer surgery, cardiopulmonary bypass, and deep hypothermic circulatory arrest times than Group B (P < 0.05). ③ Univariate analysis of baseline data: Group A had higher rates of patients aged ≥60, hypertension, history of stroke, and elevated preoperative D-dimer levels (P < 0.05). ④ Multivariate logistic analysis: Independent risk factors for postoperative delirium included age ≥60, hypertension, history of stroke, surgery time >6 hours, cardiopulmonary bypass time >3 hours, and deep hypothermic circulatory arrest time >40 minutes (OR > 1, P < 0.05).

Surgical treatment of Stanford Type A aortic dissection has a good effect, significantly improving long-term cardiac function. However, the incidence of postoperative delirium is relatively high and is closely related to factors such as age, hypertension, history of stroke, surgery time, cardiopulmonary bypass time, and deep hypothermic circulatory arrest time.

To explore the clinical presentations and outcomes among different ages and subtypes of post-operative delirium patients.

Systematic review of Published Cases.

We comprehensively searched PubMed, EMBASE, and MEDLINE for published case reports of post-operative delirium up to April 2023. The systematic review has been registered with PROSPERO. Two researchers independently conducted unblinded reviews of the full-text articles.

This study included 116 patients with post-operative delirium. Compared to post-operative delirium patients aged 65 and above, those between 18 and 65 years old have lower rates of a history of hypertension, cardiovascular disease and urinary system disorder comorbidities, as well as higher usage rates of fentanyl analogs and lorazepam. Additionally, these patients exhibit lower incidences of anemia and renal failure, along with a lower mortality rate. Compared to post-operative delirium patients aged 65 and above, those under 18 years old have a higher rate of fentanyl analog usage and a higher incidence of post-operative delirium following neurological surgeries. Among the hypoactive, hyperactive, and mixed subtypes, the reasons for surgery, such as cardiovascular diseases, reproductive system diseases, and neurological disorders, significantly varied among these three subtypes. Furthermore, substance abuse history and medication usage patterns also significantly varied among these three subtypes.

Our investigation has revealed noteworthy insights into post-operative delirium in different patient populations. Notably, age emerged as a pivotal factor. Compared to elderly patients (≥65 years), those aged 18 to 65 demonstrate better prognosis. Additionally, patients younger than 18 years with post-operative delirium have a higher incidence of delirium following neurosurgical procedures compared to those elderly patients. Additionally, a strong association was found between a history of substance abuse and hyperactive delirium. Variations in drug use patterns were observed across different subtypes. Importantly, post-operative delirium patients younger than 18 years, as well as those aged 18 to 65 with mixed-subtype delirium, exhibited similar high mortality rates as elderly patients. This underscores the need for increased attention to post-operative delirium patients under 65 and highlights the necessity of rapid identification and early intervention for these populations at risk of poor outcomes.

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023473383, Identifier [Registration ID: CRD 42023473383].

We aimed to identify a safe and effective method to assist older adults with pneumonia in tolerating the prone position for a longer duration.

This was a randomized, controlled, double-blinded study performed at the Shanghai Fourth People's Hospital. Eighty patients with pneumonia aged ≥ 65 years were included. The patients were able to spontaneous breath in the prone position and were administered intravenous dexmedetomidine or an isotonic sodium chloride solution. The cumulative daily durations of prone positioning for all patients in the two groups were recorded. The primary outcome was the percentage of patients who completed ≥ 9 h/day in the prone position. The secondary outcomes included the incidence of complications in the prone position and patient outcomes.

Eighty patients were included (average age: 79.6 ± 8.9 years). The percentage of patients who completed ≥ 9 h/day in the prone position was significantly higher in the dexmedetomidine group than in the placebo group (P = 0.011). The percentage of patients who completed ≥ 12 h/day in the prone position was also significantly greater in the dexmedetomidine group than in the placebo group (P = 0.008). There were no significant differences in other variables between the two groups.

The results of this study demonstrate that intravenous dexmedetomidine injection can significantly prolong the duration of spontaneous breathing in the prone position in elderly pneumonia patients without obvious adverse events. We provide a safe and effective method to help patients with pneumonia, especially those with delirium or cognitive impairment, who cannot tolerate the length of time needed for spontaneous breathing in the prone position to be effective.

The study was registered with the Chinese Clinical Trial Center (registration number: ChiCRT2300067383) on 2023-01-05.

Dexmedetomidine is considered to have neuroprotective effects and may reduce postoperative delirium in both cardiac and major non-cardiac surgeries. Compared with non-cardiac surgery, the delirium incidence is extremely high after cardiac surgery, which could be caused by neuroinflammation induced by surgical stress and CPB. Thus, it is essential to explore the potential benefits of dexmedetomidine on the incidence of delirium in cardiac surgery under CPB.

Randomized controlled trials studying the effect of perioperative dexmedetomidine on the delirium incidence in adult patients undergoing cardiac surgery with CPB were considered to be eligible. Data collection was conducted by two reviewers independently. The pre-specified outcome of interest is delirium incidence. RoB 2 was used to perform risk of bias assessment by two reviewers independently. The random effects model and Mantel-Haenszel statistical method were selected to pool effect sizes for each study.

PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from inception to June 28, 2023. Sixteen studies including 3381 participants were included in our systematic review and meta-analysis. Perioperative dexmedetomidine reduced the incidence of postoperative delirium in patients undergoing cardiac surgery with CPB compared with the other sedatives, placebo, or normal saline (RR 0.57; 95% CI 0.41-0.79; P = 0.0009; I2 = 61%).

Perioperative administration of dexmedetomidine could reduce the postoperative delirium occurrence in adult patients undergoing cardiac surgery with CPB. However, there is relatively significant heterogeneity among the studies. And the included studies comprise many early-stage small sample trials, which may lead to an overestimation of the beneficial effects. It is necessary to design the large-scale RCTs to further confirm the potential benefits of dexmedetomidine in cardiac surgery with CPB.

CRD42023452410.

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.

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.

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.

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.

PROSPERO (CRD42023413984).

Dexmedetomidine (DEX) has demonstrated potential as an effective agent for enhancing early postoperative cognitive function. However, there is ongoing debate regarding its optimal dosage and impact on early postoperative inflammatory response. This study aimed to assess and prioritize the effects of varying doses of DEX on early postoperative cognitive function and inflammatory response, in order to identify the most effective intervention dosage.

Randomised controlled trials (RCTs) and retrospective cohort studies (RCS) from PubMed, Embase, and Cochrane Library up to January 28, 2024, were included. The Mini-Mental State Examination (MMSE) was utilized to assess the impact of varying doses of DEX on cognitive function during the early postoperative period as the primary outcome, peripheral blood levels of IL-6 and TNF-α were considered as secondary outcomes. Meta-analysis and Bayesian Network Meta-Analysis (NMA) were conducted using R. Funnel plots were generated using Stata 15.0.

A total of 29 studies involving 2,807 patients and 25 different doses of DEX were included. DEX was given at a loading dose of 0.3-1.0 μg/kg followed by a maintenance dose of 0.1-0.5 μg/kg/h, or at a uniform intraoperative dose of 0.4-0.7 μg/kg/h. Network meta-analysis revealed most doses of DEX were significantly more effective than normal saline (NS) in improving postoperative MMSE scores (on days 1, 3, and 7) and lowering IL-6 and TNF-α levels. Probability results showed that a 1 μg/kg loading dose followed by a 0.6 μg/kg/h maintenance dose was the best dosing regimen for improving MMSE scores on postoperative days 1 (97.3%), 3 (100%), and 7 (99.9%), as well as for reducing postoperative blood IL-6 levels (1.3%). On the other hand, 0.3 μg/kg followed by 0.2 μg/kg/h was the optimal dosing regimen for reducing postoperative blood TNF-α levels (6.6%).

Compared with NS, intraoperative intravenous DEX improved early postoperative cognitive function and postoperative inflammatory response in patients undergoing elective surgery. In particular, a 1 μg/kg loading dose and a 0.6 μg/kg/h maintenance dose resulted in the best improvement in postoperative MMSE scores and blood IL-6 levels, while a 0.3 μg/kg loading dose followed by a 0.2 μg/kg/h maintenance dose is the optimal regimen for lowering postoperative blood TNF-α levels.Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=433932, identifier CRD42023433932.

Dexmedetomidine is a selective α2 receptor agonist with sedative, analgesic, anxiolytic, and anti-sympathetic effects. Dexmedetomidine is widely used for various surgical procedures performed under general anaesthesia and sedation in the intensive care unit. Dexmedetomidine was known to relieve or improve the symptoms of delirium. Schizophrenia is a common psychiatric disease, and the number of surgical patients with schizophrenia is increasing gradually. Dexmedetomidine-induced delirium in patients with schizophrenia is a particular case.

This patient was a 75-year-old woman (height: 156 cm; weight: 60 kg) with a 5-year history of schizophrenia. Her schizophrenia was well controlled with medications. She was scheduled for open reduction and internal fixation for a patellar fracture. Spinal anaesthesia was administered for surgery, and dexmedetomidine was administered intravenously to maintain sedation. The patient became delirious half an hour after the surgery began. The intravenous infusion of dexmedetomidine was discontinued immediately, intravenous propofol was subsequently administered, and the patient stopped experiencing dysphoria and fell asleep. After surgery, the patient stopped using propofol and recovered smoothly. She was transferred back to the general ward and was discharged from the hospital without any abnormal conditions on the 9th day after surgery.

To the best of our knowledge, this is the first report of a patient with schizophrenia who developed delirium during the infusion of a normal dose of dexmedetomidine without an intravenous injection of any other sedative. The exact mechanism causing dexmedetomidine-induced delirium remains unclear, and this adverse reaction is rare and easy to ignore. Clinicians and pharmacists should be vigilant in identifying this condition.

Postoperative delirium (POD), an acute and variable disturbance in cognitive function, is an intricate and elusive phenomenon that occurs after cardiac surgery. Despite progress in surgical techniques and perioperative management, POD remains a formidable challenge, imposing a significant burden on patients, caregivers, and healthcare systems.

This prospective observational study involved 307 patients who underwent cardiac surgery. Data on the occurrence of delirium, clinical parameters, and postoperative characteristics were collected. A multivariate analysis was performed to assess the relationship between POH and POD.

Sixty-one patients (21%) developed delirium, with an average onset of approximately 5 days postoperatively and a duration of approximately 6 days. On multivariate analysis, POH was significantly associated with POD, and the adjusted odds ratios indicated that patients with POH were more likely to develop delirium (OR, 5.61; p = 0.006). Advanced age (OR, 1.11; p = 0.002), emergency surgery (OR, 8.31; p = 0.001), and on-pump coronary artery bypass grafting were identified as risk factors of POD. Patients who developed delirium were typically older, more likely to be male, and had higher morbidity rates than those who did not.

POH is significantly associated with delirium in critically ill patients after cardiac surgery. Surgical complexity and advanced age contribute to the risk of developing POD and poor postoperative outcomes.

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, 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.

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).

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.

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.

The number of elderly patients who require surgery as their primary treatment has increased rapidly in recent years. Among 300 million people globally who underwent surgery every year, patients aged 65 years and over accounted for more than 30% of cases. Despite medical advances, older patients remain at higher risk of postoperative complications. Early diagnosis and effective prediction are essential requirements for preventing serious postoperative complications. In this study, we aim to provide new biomarker combinations to predict the incidence of postoperative intensive care unit (ICU) admissions > 24 h in elderly patients.

This investigation was conducted as a nested case-control study, incorporating 413 participants aged ≥ 65 years who underwent non-cardiac, non-urological elective surgeries. These individuals underwent a 30-day postoperative follow-up. Before surgery, peripheral venous blood was collected for analyzing serum creatinine (Scr), procalcitonin (PCT), C-reactive protein (CRP), and high-sensitivity CRP (hsCRP). The efficacy of these biomarkers in predicting postoperative complications was evaluated using receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) values.

Postoperatively, 10 patients (2.42%) required ICU admission. Regarding ICU admissions, the AUCs with 95% confidence intervals (CIs) for the biomarker combinations of Scr × PCT and Scr × CRP were 0.750 (0.655-0.845, P = 0.007) and 0.724 (0.567-0.882, P = 0.015), respectively. Furthermore, cardiovascular events were observed in 14 patients (3.39%). The AUC with a 95% CI for the combination of Scr × CRP in predicting cardiovascular events was 0.688 (0.560-0.817, P = 0.017).

The innovative combinations of biomarkers (Scr × PCT and Scr × CRP) demonstrated efficacy as predictors for postoperative ICU admissions in elderly patients. Additionally, the Scr × CRP also had a moderate predictive value for postoperative cardiovascular events.

China Clinical Trial Registry, ChiCTR1900026223.

Postoperative delirium is associated with morbidity and mortality, and its incidence varies widely. Using known predisposing and precipitating factors, we sought to develop postoperative delirium prediction models for noncardiac surgical patients.

Retrospective prediction model study.

Major quaternary medical center.

Our January 2016 to June 2020 training dataset included 51,677 patients of whom 2795 patients had delirium. Our July 2020 to January 2022 validation dataset included 14,438 patients of whom 912 patients had delirium.

None.

We trained and validated two static prediction models and one dynamic delirium prediction model. For the static models, we used random survival forests and traditional Cox proportional hazard models to predict postoperative delirium from preoperative variables, or from a combination of preoperative and intraoperative variables. We also used landmark modeling to dynamically predict postoperative delirium using preoperative, intraoperative, and postoperative variables before onset of delirium.

In the validation analyses, the static random forest model had a c-statistic of 0.81 (95% CI: 0.79, 0.82) and a Brier score of 0.04 with preoperative variables only, and a c-statistic of 0.86 (95% CI: 0.84, 0.87) and a Brier score of 0.04 when preoperative and intraoperative variables were combined. The corresponding Cox models had similar discrimination metrics with slightly better calibration. The dynamic model - using all available data, i.e., preoperative, intraoperative and postoperative data - had an overall c-index of 0.84 (95% CI: 0.83, 0.85).

Using preoperative and intraoperative variables, simple static models performed as well as a dynamic delirium prediction model that also included postoperative variables. Baseline predisposing factors thus appear to contribute far more to delirium after noncardiac surgery than intraoperative or postoperative variables. Improved postoperative data capture may help improve delirium prediction and should be evaluated in future studies.

Dexmedetomidine plays a pivotal role in mitigating postoperative delirium and cognitive dysfunction while enhancing the overall quality of life among surgical patients. Nevertheless, the influence of dexmedetomidine on such complications in various anaesthesia techniques remains inadequately explored. As such, in the present study, a meta-analysis was conducted to comprehensively evaluate its effects on postoperative delirium and cognitive dysfunction.

A number of databases were searched for randomised controlled trials comparing intravenous dexmedetomidine to other interventions in preventing postoperative delirium and cognitive dysfunction in non-cardiac and non-neurosurgical patients. These databases included PubMed, Embase, and Cochrane Library. Statistical analysis and graphing were performed using Review Manager, STATA, the second version of the Cochrane risk-of-bias tool for randomised controlled trials, and GRADE profiler.

This meta-analysis comprised a total of 24 randomised controlled trials, including 20 trials assessing postoperative delirium and 6 trials assessing postoperative cognitive dysfunction. Across these 24 studies, a statistically significant positive association was observed between intravenous administration of dexmedetomidine and a reduced incidence of postoperative delirium (RR: 0.55; 95% CI 0.47 to 0.64, p < 0.00001, I2 = 2%) and postoperative cognitive dysfunction (RR: 0.60; 95% CI 0.38 to 0.96, p = 0.03, I2 = 60%). Subgroup analysis did not reveal a significant difference in the incidence of postoperative delirium between the general anaesthesia and non-general anaesthesia groups, but a significant difference was observed in the incidence of postoperative cognitive dysfunction. Nonetheless, when the data were pooled, it was evident that the utilisation of dexmedetomidine was associated with an increased incidence of hypotension (RR: 1.42; 95% CI 1.08 to 1.86, p = 0.01, I2 = 0%) and bradycardia (RR: 1.66; 95% CI 1.23 to 2.26, p = 0.001, I2 = 0%) compared with other interventions. However, there was no significantly higher occurrence of hypertension in the DEX groups (RR = 1.35, 95% CI 0.81-2.24, p = 0.25, I2 = 0%).

Compared with other interventions, intravenous dexmedetomidine infusion during non-cardiac and non-neurosurgical procedures may significantly reduce the risk of postoperative delirium and cognitive dysfunction. The results of subgroup analysis reveal a consistent preventive effect on postoperative delirium in both general and non-general anaesthesia groups. Meanwhile, continuous infusion during general anaesthesia was more effective in reducing the risk of cognitive dysfunction. Despite such findings, hypotension and bradycardia were more frequent in patients who received dexmedetomidine during surgery.

This meta-analysis aimed to assess whether continuous intravenous administration of DEX during surgery can be part of the measures to prevent the onset of postoperative delirium and postoperative cognitive dysfunction in elderly individuals following regional anesthesia.

We searched the databases of PubMed, Embase, the Cochrane Library and China National Knowledge Infrastructure (by June 1, 2023) for all available randomized controlled trials assessing whether intravenous application of dexmedetomidine can help with postoperative delirium and postoperative cognitive dysfunction in the elderly with regional anesthesia. Subsequently, we carried out statistical analysis and graphing using Review Manager software (RevMan version 5.4.1) and STATA software (Version 12.0).

Within the scope of this meta-analysis, a total of 18 randomized controlled trials were included. Among them, 10 trials aimed to assess the incidence of postoperative delirium as the primary outcome, while the primary focus of the other 8 trials was on the incidence of postoperative cognitive dysfunction. The collective evidence from these 10 studies consistently supports a positive relationship between the intravenous administration of dexmedetomidine and a decreased risk of postoperative delirium (RR: 0.48; 95%CI: 0.37 to 0.63, p < 0.00001, I2 = 0%). The 8 literature articles and experiments evaluating postoperative cognitive dysfunction showed that continuous intravenous infusion of dexmedetomidine during the entire surgical procedure exhibited a positive preventive effect on cognitive dysfunction among the elderly population with no obvious heterogeneity (RR: 0.35; 95%CI: 0.25 to 0.49,p < 0.00001, I2 = 0%).

Administering dexmedetomidine intravenously during surgery can potentially play a significant role in preventing postoperative delirium and postoperative cognitive dysfunction in patients older than 60 years with regional anesthesia according to this meta-analysis.

Postoperative delirium (POD) is considered the most common postoperative neurological complication in elderly patients. The aim of this study was to evaluate the efficacy of the administration of ketofol versus dexmedetomidine (DEX) for minimizing POD in elderly patients undergoing urgent exploration for intestinal obstruction.

This prospective double-blinded randomized clinical trial was conducted on 120 elderly patients undergoing urgent exploration for intestinal obstruction. Patients were randomly allocated to one of the three groups: Group C (control group) patients received normal saline 0.9%, group D received dexmedetomidine, and group K received ketofol (ketamine: propofol was 1:4). The primary outcome was the incidence of POD. Secondary outcomes were incidence of emergence agitation, postoperative pain, consumption of rescue opioids, hemodynamics, and any side effects.

The incidence of POD was statistically significantly lower in ketofol and DEX groups than in the control group at all postoperative time recordings. Additionally, VAS scores were statistically significantly decreased in the ketofol and DEX groups compared to the control group at all time recordings except at 48 and 72 h postoperatively, where the values of the three studied groups were comparable. The occurrence of emergence agitation and high-dose opioid consumption postoperatively were found to be significant predictors for the occurrence of POD at 2 h and on the evening of the 1st postoperative day.

The administration of ketofol provides a promising alternative option that is as effective as DEX in reducing the incidence of POD in elderly patients undergoing urgent exploration for intestinal obstruction.

This clinical trial was approved by the Institutional Review Board (IRB) at Zagazig University (ZU-IRB# 6704// 3/03/2021) and ClinicalTrials.gov (NCT04816162, registration date 22/03/ 2021). The first research participant was enrolled on 25/03/2021).

Postoperative delirium (POD) is of great concern as a complication of surgery in older adult patients. Sedation strategies influence the development of POD. This study compared how sedation strategies administered during spinal anesthesia influenced POD in patients aged ≥65 years undergoing elective surgery for hip fracture repair.

A randomized clinical trial was conducted from 1 August 2021 to 30 June 2022 at a single academic medical center. Two hundred and twenty-six patients were randomly divided into four groups: lighter sedation with propofol (LP), heavier sedation with propofol (HP), lighter sedation with dexmedetomidine (LD), and heavier sedation with dexmedetomidine (HD). The incidence of delirium was the primary outcome and was assessed daily by the blinded Confusion Assessment Method.

There was a significant association between dexmedetomidine (LD+HD group) and a lower incidence of delirium (11.9% [13/109] vs the propofol group (23.6% [26/110]; Risk ratio, 0.51; 95% CI, 0.274 to 0.929; p=0.024). In the propofol group, heavier sedation had a higher rate of POD (32.7% [18/55] vs the lighter sedation group (14.5% [8/55]; Risk ratio, 2.25; 95% CI, 1.069 to 4.736; p=0.025).

Dexmedetomidine was associated with a lower incidence of delirium than that with propofol among older patients with hip fractures. In patients that received propofol, heavier sedation was associated with high incidence of POD.

Reducing hypotension is crucial as hypotension is the most common side effect of spinal anesthesia, and in older patients with various comorbidities, it can lead to fatality. We hypothesized that continuous infusion of norepinephrine could effectively prevent hypotension in older patients undergoing hip surgery under spinal anesthesia with propofol sedation. The study randomly assigned patients aged ≥ 70 years to either a control (Group C, n = 35) or a norepinephrine group (Group N, n = 35). After spinal anesthesia, continuous infusion of propofol and normal saline or norepinephrine was initiated. The number of hypotensive episodes, the primary outcome, as well as other intraoperative hemodynamic events and postoperative complications were compared. In total, 67 patients were included in the final analysis. The number of hypotensive episodes was significantly higher in Group C than in Group N (p < 0.001). Furthermore, Group C required a greater amount of fluid to maintain normovolemia (p = 0.008) and showed less urine output (p = 0.019). However, there was no difference in postoperative complications between the two groups. Continuous intravenous infusion of prophylactic norepinephrine prevented hypotensive episodes, reduced the requirement of fluid, and increased the urine output in older patients undergoing unilateral hip surgery under spinal anesthesia with propofol sedation.Clinical trial registration number: KCT0005046 ( https://cris.nih.go.kr ). IRB number: 2020-0533 (Institutional Review Board of Asan Medical Center, approval date: 13/APR/2020).