European Society of Anaesthesiology evidence-based and consensus-based guideline on postoperative delirium

'Transauricular vagus nerve stimulation' for prevention of postoperative delirium in elderly patients undergoing major surgery: a study protocol for a multicentre, participant-blinded and assessor-blinded, randomised, controlled trial

INTRODUCTION

Postoperative delirium (POD) is a frequent complication in elderly patients undergoing major surgery. Research has shown that neuroinflammation, postoperative pain and autonomic nervous system dysfunction play significant roles in its onset. Vagus nerve stimulation (VNS) has the potential to reduce inflammation, ease postoperative pain and aid in recovery by enhancing acetylcholine release and activating the cholinergic anti-inflammatory pathway. This study aims to assess the effectiveness and safety of transauricular VNS (ta-VNS) in preventing POD in elderly patients undergoing major surgery.

METHODS AND ANALYSIS

This multicentre, participant-blinded and assessor-blinded, randomised, parallel-group controlled trial will compare the incidence of POD in elderly patients undergoing major surgery who receive ta-VNS versus sham stimulation. A total of 300 eligible patients will be randomly assigned in a 1:1 ratio to either the active or sham stimulation group. The active stimulation group will receive electrical stimulation to the left cymba conchae at a frequency of 30 Hz and a pulse width of 250 µs, with a 30 s on/30 s off cycle. The intensity will start at 0.4V and be increased in 0.4V increments until a tingling sensation is felt, then adjusted to the highest tolerable level without pain. After obtaining informed consent and randomisation, the initial intervention will begin in the preoperative area and continue throughout the surgery. For the four postoperative days, the intervention will be administered twice daily in 2-hour sessions each morning and afternoon. The sham group will follow the same procedure, with electrodes placed on the left cymba conchae. After adjusting the stimulation intensity, the device will be switched off. The primary outcome is the incidence of POD from postoperative day 0 to day 7 or discharge. Secondary outcomes include the severity of POD, quality of recovery, sleep quality and adverse events.

ETHICS AND DISSEMINATION

The protocol was approved by Sir Run Run Shaw Hospital Affiliated to Zhejiang University School of Medicine on 9 January 2024 (Approval number: 20240014), and the trial was registered on the Chinese Clinical Trial Registry on 21 February 2024, prior to recruitment. The study will be performed according to the guidelines of the Declaration of Helsinki. Written informed consent will be obtained from all participants. The results will be submitted for publication in a refereed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2400081078.

Immersive Virtual Reality Versus Video Distraction for the Management of Emergence Delirium in Children: A Randomized Controlled Study

PURPOSE

Emergence delirium (ED) presents challenges for both parents and health care providers in pediatric surgical settings. This study aims to evaluate the effectiveness of immersive virtual reality (VR) distraction and video distraction combined with parental presence in reducing ED in preschool-aged children undergoing elective surgery.

DESIGN

A prospective, randomized, controlled clinical trial was conducted with 90 children ages 4 to 7. Participants were randomly assigned to three groups: VR distraction (group V), tablet video distraction with parental presence (group T), and standard care (group C). The primary endpoints were the incidence of ED and Pediatric Anesthesia Emergence Delirium Scale scores, with secondary measures encompassing scores from the Parental Separation Anxiety Scale and the Faces, Legs, Activity, Cry, Consolability (FLACC) scale.

METHODS

Participants were assigned to one of the three intervention groups, and relevant scales were used to assess ED, parental separation anxiety, and postoperative pain. The immersive VR distraction and video distraction with parental presence interventions were compared against standard care.

FINDINGS

Immersive VR distraction significantly reduced the incidence of ED (6.67% in group V vs 40% in group T and 60% in group C), and the incidence of ED in group V was notably lower than in the other groups (P = .023 vs group T and P = .004 vs group C). Children in group V displayed significantly lower FLACC compared with the other groups as well (P < .05). However, no significant differences between the 3 groups were observed in perioperative anxiety as assessed by the Parental Separation Anxiety Scale scores (P = .27).

CONCLUSIONS

This study underscores the potential of immersive VR distraction as an effective intervention for mitigating ED in pediatric surgical patients. The findings suggest that incorporating VR technology during the perioperative period can positively impact postoperative outcomes. Further research in diverse surgical contexts is recommended to validate these findings and explore the broader applicability of VR distraction in pediatric health care settings.

Global Research Trends in Postoperative Delirium and Its Risk Factors: A Bibliometric and Visual Analysis

PURPOSE

Postoperative delirium (POD) is one of the most frequent complications after surgery which is closely associated with many adverse outcomes, including high mortality and low quality of life. This study aims to carry out a bibliometric analysis of POD and its risk factors from 2012 to 2022 to reveal the research status and hot spots.

DESIGN

This study is a bibliometric and visualized analysis.

METHODS

Relevant publications between 2012 and 2022 were extracted from the Web of Science Core Collection database. CiteSpace software (v6.1. R2, Drexel University), VOSviewer software (v1.6.18, Leiden University), and the Online Analysis Platform of Literature Metrology were used to analyze research attributes. These publications were used to analyze research attributes, including countries, journals, institutions, authors, keywords, and burst detection, to predict trends and hot spots.

FINDINGS

We included a total of 1,324 related documents from 2012 to 2022. The literature on POD has increased significantly since 2016. The United States and Harvard University were the leading literature publishing country (436/1324, 32.9%) and institution (112/1324, 8.5%). Anesthesia and Analgesia was the most frequently published journal. Keywords analysis with VOSviewer revealed that the keywords could be divided into five clusters, including anesthesia techniques, cardiac surgery, risk factors, intraoperative anesthesia monitoring, and postoperative cognitive dysfunction. We included a total of 198 POD risk factors documents, and the literature on POD risk factors increased. The People's Republic of China and Harvard University were the leading literature publishing country (53/198, 26.8%) and institution (12/198, 6.1%). Elderly, hip surgery, frailty, postoperative pain, cardiac surgery, dementia, and depression are keywords that are risk factors for POD.

CONCLUSIONS

The number of literature on POD in the field of anesthesia has increased significantly. Risk factors and anesthesia techniques are still key areas of research. Encephalogram, the use of sedatives, and perioperative nursing may be the new research focus. Older adults, hip fractures, cardiac surgery, liver transplants, dementia, and depression are hot words in the field of POD risk factors.

Mapping the Nursing Literature on Postoperative Delirium: A Bibliometric Analysis

PURPOSE

To provide a structured, macroscopic overview of nursing research on postoperative delirium through bibliometric analysis, assessing its characteristics and progress.

DESIGN

Bibliometric analysis study.

METHODS

For the bibliometric analysis study, the Web of Science database was selected, and the data analyzed was included until August 28, 2024. The analysis was performed using the "Biblioshiny" application available in the Bibliometrix R package.

FINDINGS

Between 1977 and 2024, 535 nursing articles on postoperative delirium were published in 313 sources. When examining the annual scientific output of nursing studies on postoperative delirium, the most prolific journals were found to be Journal of Clinical Nursing (n = 18), Journal of Perianesthesia Nursing (n = 13), and Journal of the American Geriatrics Society (n = 13). According to Bradford's law-based analyses, there are 313 productive journals in the nursing literature on postoperative delirium. These journals are distributed as follows: 29 in the first zone, 108 in the second zone, and 176 in the third zone. Authors and articles were organized according to Lotka's law. The majority (88.9%) of the authors (n = 2,486) had 1 article, 8.7% had 2 articles (n = 243), and 1.5% had 3 articles (n = 43), while 0.2% (n = 7) had more than 5 publications. Recent trends show a shift toward research on recovery, guidelines, and 3 outcomes, with studies on experience, impact, and cardiac surgery. The countries with the highest number of publications were identified as the United States, Germany, and China. Global collaborations on this topic were: United States-Canada (n = 8), United States-Germany (n = 7), United States -United Kingdom (n = 7).

CONCLUSIONS

This bibliometric study provides a comprehensive and integrative review of the global literature on postoperative delirium in nursing.

Clinical and intracranial electrophysiological signatures of post-operative and post-ictal delirium

OBJECTIVES

(1) Gain insight into the mechanisms of postoperative delirium (POD). (2) Determine mechanistic overlap with post-ictal delirium (PID). Epilepsy patients undergoing intracranial electrophysiological monitoring can experience both POD and PID, and thus are suitable subjects for these investigations.

METHODS

POD was assessed daily after surgery. PID was assessed following seizures. Resting state data were collected following delirium assessments, during a control period, and during sleep. Slow-wave activity (SWA: 1-4 Hz) and resting state functional connectivity were compared between different time points and according to delirium status.

RESULTS

POD was present in 6 of 20 participants. Post-operatively, SWA was globally elevated in all participants but highest in POD+ participants. POD+ participants exhibited altered functional connectivity compared to POD-. These differences persisted even after resolution of delirium. PID was present in 7 of 15 participants and was predicted by seizures involving prefrontal cortex. PID+ participants exhibited higher post-ictal SWA versus PID-; no differences in functional connectivity were observed. Post-operative and post-ictal SWA was comparable to sleep in some participants.

CONCLUSIONS

Elevated SWA may predispose patients to both post-operative and post-ictal delirium and may indicate overlapping mechanisms.

SIGNIFICANCE

Delirium treatments focused on SWA may be most effective for ameliorating cognitive symptoms.

Concomitant Use of Intravenous Remimazolam With Inhalation Anesthesia and Subsequent Emergence Delirium in Children: A Systematic Review and Meta-Analysis

Emergence delirium (ED) is a typical postoperative complication in pediatric anesthesia, especially with inhalational agents. Remimazolam, a short-acting benzodiazepine, shows potential for reducing the occurrence of ED. Given limited evidence of its use in pediatric anesthesia, we evaluated the efficacy and safety of remimazolam by conducting a systematic review and meta-analysis. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and International Clinical Trials Registry Platform (ICTRP) databases were explored for studies on remimazolam in pediatric anesthesia. The studies included were randomized controlled trials (RCTs), prospective and retrospective cohort studies, case series, and case reports. Eligible patients were pediatric patients as American Society of Anesthesiologists Physical Status I or II who underwent sevoflurane-based general anesthesia. Primary outcomes included ED and emergence time. Study quality was assessed using the Risk of Bias 2 tool, and evidence certainty was evaluated by the Grading of Recommendations, Assessment, Development, and Evaluation approach. Random-effects meta-analyses estimated pooled risk ratios (RRs). Three RCTs (n = 310) were included. A 0.2 mg/kg remimazolam bolus may result in a large reduction in ED (RR 0.26, 95% confidence intervals (CIs) 0.16 to 0.44, I² = 0%; low certainty, three studies). Continuous infusion showed similar effects (RR 0.22, 95% CIs 0.08 to 0.60, low certainty, one study). Emergence times varied by dosage and administration method, with continuous infusion associated with prolonged emergence times (mean difference 5.7 minutes, 95% CIs 3.67 to 7.73, low evidence, one study). Evidence certainty ranged from very low to low, with the 0.2 mg/kg bolus rated very low. The concomitant use of intravenous remimazolam with inhalation anesthesia may reduce the ED in pediatric patients. However, evidence on emergence times remains inconclusive. Anesthetists could potentially use remimazolam to reduce the ED in children after inhalation anesthesia, but further investigation regarding its efficacy and safety across diverse populations is warranted.

Sublingual sufentanil after orthopaedic and abdominal surgery: long-term outcome and safety

BACKGROUND

Acute postoperative pain management often requires opioid treatment with patient-controlled analgesia (PCA). Non-invasive PCA with a sublingual sufentanil tablet system (SSTS) may reduce acute pain sufficiently, but opioids are associated with central nerve system side effects and risk of long-term opioid use postoperatively. The objective of this study was to observe the SSTS to assess the incidence of postoperative chronic pain (PCP) and postoperative delirium (POD).

METHODS

This was a longitudinal cohort study based at a university hospital between November 2017 and November 2021. Adults undergoing elective orthopaedic knee or abdominal surgery planned for PCA as postoperative pain management were included. They received the SSTS in addition to a standardised pain medication protocol depending on the surgery they underwent. Exclusion criteria were pregnancy, emergency surgery, concurrent participation in another clinical trial and chronic opioid use before surgery. Patients were followed after surgery in hospital and over 3 and 12 months for pain, cognitive function and side effects.

RESULTS

Altogether N = 80 patients were included with SSTS postoperatively. Daily pain experience decreased from pre-operatively 89.2% of patients to 45.7% and 22.5% at 3 and 12 months. None of our patients developed postoperative delirium after surgery. Patients reported high overall satisfaction with SSTS (median 8.0/10 points, IQR 3). However, 51% of patients had difficulties with handling the SSTS and required acute replacement of the authentication tag.

CONCLUSIONS

SSTS sufficiently treated acute postoperative pain without incidence of POD and demonstrated good tolerability and overall ease. Postoperative pain improved significantly over time but 22% still reported chronic pain related to surgery. Technical issues with the identification thumb tag limited the feasibility of SSTS.

TRIAL REGISTRATION

This prospective longitudinal cohort study was approved by the ethics committee of the Charité Universitätsmedizin Berlin (Ethics committee 2, Campus Charité Virchow Klinikum, EA2/041/17, Prof. Dr. jur. R. Seeland, 21.03.2017) and was registered in the study register ( https://clinicaltrials.gov/ct2/show/NCT03133858 ).

Prevention and management of postoperative delirium in adult patients: a best practice implementation project

OBJECTIVE

To describe the process of implementing evidence-based best practices to improve the prevention and management of Postoperative Delirium in the Post-Anesthesia Care Unit.

METHOD

Report on an evidence implementation project applying the JBI based on the audit and feedback process, with a structured approach to identifying and managing barriers in accordance with recommended clinical practices. Medical records, electronic nursing record systems, and staff interviews were used to assess compliance rates.

RESULTS

In the baseline audit, a zero compliance rate was found in most criteria in relation to the best evidence. Following this phase, interprofessional training was carried out, a validated tool was provided to identify patients at risk of delirium, and changes were made to the electronic nursing records system. In the first follow-up audit, there was an increase in the compliance rate in four of the nine criteria audited. Four criteria achieved 100% compliance in the second follow-up audit.

CONCLUSION

Best practices were implemented that contributed to improving the prevention and management of Postoperative Delirium. Subsequent to new training and re-auditing after one year, an increase in adherence to best practices was observed.

Perioperative Anxiety: Current Status and Future Perspectives

Perioperative anxiety is a multifaceted phenomenon that significantly impacts patients undergoing surgical procedures. Despite advancements in surgical techniques and anesthetic management, the psychological burden associated with anesthesia and surgery remains a significant challenge for healthcare providers. Up to 30% of patients suffer from anesthesia-related preoperative anxiety, irrespective of whether the procedure is elective or emergent. Notably, anxiety can adversely affect patient outcomes, including pain management, patient safety, overall quality of care, and patient satisfaction. Addressing perioperative anxiety requires a comprehensive understanding of its causes, assessment tools, and management strategies to ensure optimal perioperative care. This review examines the historical context, incidence, causes, pathophysiology, assessment tools, and current evidence regarding management strategies for anesthesia-related anxiety, and provides an outlook on future directions for research and everyday practice.

Free Flap Enhanced Recovery Protocols in Head and Neck Surgery

Enhanced recovery after surgery (ERAS) protocols facilitates a standardized patient care regimen with a goal of reducing the metabolic stress of surgery. Adapted to head and neck free flap reconstructive surgery in 2017, these protocols focused on several key domains such as perioperative nutritional optimization, multimodal pain control, and early mobilization. Studies have shown that in addition to ERAS implementation, the maintenance and improvement of ERAS protocol compliance rates improve perioperative outcomes such as hospital length of stay and decrease major postoperative complications.

Recent developments in delirium after oral and maxillofacial free-flap reconstruction

Postoperative delirium (POD), a common complication following surgery and anesthesia, is particularly prone to occur after reconstruction surgery in the oral and maxillofacial region. The occurrence of POD seriously affects the incidence of postoperative complications, the survival of free flaps, the length of hospital stays, and brings great pain to patients and their families, and even increases perioperative mortality. Currently, a large number of studies have reported on the risk factors for POD after oral and maxillofacial free-flap reconstruction. Multiple independent risk factors have been identified, including age, history of excessive alcohol consumption, and perioperative nutritional status. This review summarizes the relevant literature and hopes to provide insights for the prevention of POD in high-risk patients.

Effect of perioperative esketamine use on emergency delirium in children undergoing tonsillectomy and adenoidectomy: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Emergence delirium(ED) is a common postoperative complication in children undergoing tonsillectomy and adenoidectomy under general anesthesia. There is no high-quality evidence on the relationship between esketamine and ED. The systematic review and meta-analysis was performed to investigate the effect of perioperative esketamine use on ED in children undergoing tonsillectomy and adenoidectomy.

METHOD

We searched Embase, The Cochrane Library, PubMed, MEDLINE, Web of Science, China National Knowledge Infrastructure (CNKI), WanFang, VIP, and SinoMed from inception to 1 September, 2024. Two evaluators identified randomized controlled trials comparing perioperative use of esketamine with placebo or other drugs in children undergoing tonsillectomy and adenoidectomy. Incidence of ED was the primary outcome of the study. Data synthesis was performed by using Review Manager 5.4 software.

RESULTS

Twenty-three relevant studies involving a total of 1,996 children were identified. Perioperative use of esketamine reduced the incidence of ED in children undergoing tonsillectomy and adenoidectomy (RR = 0.33, 95% CI: [0.25, 0.44], p < 0.00001, I 2 = 0%). Scores of ED were lower in the esketamine group than in the control group (SMD = -1.20, 95% CI: [-1.56,-0.84], p < 0.00001, I 2 = 88%). Children in the esketamine group have lower postoperative pain scores (SMD = -0.51, 95% CI: [-0.80,-0.39], p < 0.00001, I 2 = 74%). Esketamine was also associated with a lower incidence of adverse events (RR = 0.75, 95% CI: [0.57, 0.99], p = 0.04, I 2 = 62%). We also found that the use of esketamine reduced the length of stay in the post-anesthetic care unit (PACU) but had no effect on the time to extubation.

CONCLUSION

Perioperative use of esketamine could significantly reduce the incidence of ED in children undergoing tonsillectomy and adenoidectomy. However, the optimal dose and timing of esketamine administration for preventing ED remains to be explored.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=558560, PROSPERO: CRD42024558560.

Effectiveness of non-pharmacological intervention protocol for prevention of postoperative delirium in the surgical intensive care unit

Postoperative delirium (POD) is a common adverse event in patients admitted to the intensive care unit (ICU). We aimed to determine the effectiveness of a multicomponent non-pharmacological intervention protocol to reduce the incidence of POD in elderly patients admitted to the surgical ICU (SICU). This before-and-after cohort study included 300 patients aged ≥ 65 years who were admitted to the SICU within 7 days postoperatively with an anticipated SICU stay > 24 h. During the pre-intervention period, patients received medical care based on the attending physicians. While during the intervention, patients received the same medical care plus a multicomponent non-pharmacological intervention protocol. POD was monitored twice daily using the Confusion Assessment Method for the ICU. Demographic and clinical data during SICU stay were collected and compared between the pre-intervention and intervention periods. The primary outcome was POD incidence. The secondary outcomes were POD duration, delirium-free days, and other clinical outcomes. The incidences of POD during the pre-intervention and intervention periods were not different (40.0% vs. 38.0%, P = 0.723; OR 0.92, 95% CI 0.58-1.46). Multivariate regression analyses with two different models demonstrated that the multicomponent non-pharmacological intervention protocol was not associated with POD prevention (OR 0.70, 95% CI 0.39-1.25 for Model 1 and OR 0.63, 95% CI 0.37-1.08 for Model 2). The protocol was associated with lower incidence of SICU events, particularly self-removal of endotracheal tube and nosocomial infection. Implementation of the multicomponent non-pharmacological intervention protocol was not associated with POD prevention in elderly patients admitted to the SICU.Trial registration Thai Clinical Trials Registry. Trial No. TCTR20181201001. Retrospective registered 01 December 2018.

Development of Predictive Model of Surgical Case Durations Using Machine Learning Approach

Optimizing operating room (OR) utilization is critical for enhancing hospital management and operational efficiency. Accurate surgical case duration predictions are essential for achieving this optimization. Our study aimed to refine the accuracy of these predictions beyond traditional estimation methods by developing Random Forest models tailored to specific surgical departments. Utilizing a comprehensive dataset, we applied several machine learning algorithms, including RandomForest, XGBoost, Linear Regression, LightGBM, and CatBoost, and assessed their performance using Mean Absolute Error (MAE), Root Mean Squared Error (RMSE), and R-Squared (R2) metrics. Our findings highlighted that Random Forest models excelled in department-specific applications, achieving an MAE of 16.32, an RMSE of 31.19, and an R2 of 0.92, significantly outperforming general models and conventional estimates. This improvement emphasizes the advantage of customizing models to fit the distinct characteristics and data patterns of each department. Additionally, our SHAP-based feature importance analysis identified morning operation timing, ICU ward assignments, operation codes, and surgeon IDs as key factors influencing surgical duration. This suggests that a detailed and nuanced approach to model development can substantially increase prediction accuracy. By providing a more accurate, reliable tool for predicting surgical case durations, our department-specific Random Forest models promise to enhance surgical scheduling, leading to more effective OR management. This approach underscores the importance of leveraging tailored, data-driven models to improve healthcare outcomes and operational efficiency.

Polypharmacy and anticholinergic burden as risk factors for postoperative delirium in surgical medicine

PURPOSE

Polypharmacy is a widespread phenomenon in older patients. In particular, the anticholinergic burden of medication is an important risk factor for delirium due to age-related changes in the cholinergic system.

METHODS

Preoperative medication, including the calculation of the anticholinergic burden (ACB), was recorded in a prospective study (421 patients) to identify potential risks associated with medication intake. Postoperative delirium screening was carried out daily.

RESULTS

The study included 199 women (47.3%) and 222 men (52.7%) aged 80.8 ± 6.7 years and 78.8 ± 6.2 years, respectively. Antidepressants odds ratio (OR) 3.16 (95% confidence interval. CI, 1.51-6.64), antidiabetic drugs OR 2.53 (95% CI 1.27-5.03), neuroleptics OR 3.52 (95% CI 1.70-7.28) and Parkinson medication OR 5.88 (95% CI 1.95-17.7) showed a significantly higher risk for delirium. The ACB score revealed an anticholinergic burden in 43 patients (10.4%). The delirium rate was 25.6% (n = 11) and 11.0% (n = 40) had no anticholinergic burden. A significant correlation can be demonstrated with χ2(1) = 7.52, p = 0.006, Cramer's V = 0.136. There was a 2.79-fold higher risk of delirium (OR 2.79, 95% CI 1.31-5.97).

CONCLUSION

The standardized recording of medication is essential, especially when identifying patients at risk of suffering from delirium. The use of the ACB score to assess the anticholinergic burden is a simple and reliable screening tool and should be part of a preoperative geriatric assessment.

Anesthesia/surgery leads to blood-brain barrier disruption via the transcellular and paracellular pathways, and postoperative delirium-like behavior: A comparative study in mice of different ages

AIMS

Postoperative delirium (POD) is a common complication of anesthesia and surgery, with a higher incidence in elderly patients. Disruption of the blood-brain barrier (BBB) is considered one of the key mechanisms underlying POD. Therefore, the present study aimed to investigate the effects of different BBB permeability alteration pathways on POD in mice of various ages.

METHODS

C57BL/6 J mice aged 4 and 16 months underwent exploratory laparotomy under sevoflurane anesthesia. Behavioral tests were conducted 24 h prior to surgery, as well as 6, 9, and 24 h postoperatively. Frontal cortex tissue was collected to detect the levels of BBB-related proteins and mRNA.

RESULTS

At 6 and 9 h after anesthesia/surgery, 4-month-old mice showed poorer performance on behavioral tests than their untreated counterparts. However, 16-month-old mice exhibited worse behavioral test results at 6, 9, and 24 h after surgery. Anesthesia/surgery 6 h postoperatively increased the expression of vesicle-associated proteins, and BBB leakage in 4-month-old mice. In 16-month-old mice, anesthesia/surgery altered the expression of tight junction proteins, vesicle-associated proteins, and BBB leakage at 6 and 24 h postoperatively.

CONCLUSION

Overall, our results suggest that anesthesia/surgery leads to age-dependent cognitive decline, and is associated with differences in the BBB injury pathways among mice of different ages. The transcellular pathway (transcytosis), compared to the paracellular pathway (tight junction), is more vulnerable to damage following anesthesia/surgery. This study provides new evidence for the improvement of POD through protection of the BBB.

Intraoperative hypotension and postoperative delirium in elderly male patients undergoing laryngectomy: a single-center retrospective cohort study

BACKGROUND

Postoperative delirium (POD) is a common, transient postoperative cognitive dysfunction in elderly patients. The relationship between POD and intraoperative hypotension remains unclear. This study aims to determine if intraoperative hypotension predicts POD in elderly male patients undergoing laryngectomy.

METHODS

This study included male patients over 65 years old who underwent laryngectomy between April 2018 and January 2022. The Confusion Assessment Method (CAM) was used to diagnose delirium. Intraoperative hypotension was defined as a Mean Arterial Pressure (MAP) during surgery that was less than 30% of the preoperative level for at least 30 minutes. The relationship between intraoperative hypotension and POD incidence was adjusted for patient demographics and surgery-related factors.

RESULTS

Out of 428 male patients, 77 (18.0%) developed POD, and 166 (38.8%) experienced intraoperative hypotension. Surgery duration ≥ 300 minutes (OR = 1.873, 95% CI 1.041-3.241, p = 0.036), intraoperative hypotension (OR = 1.739, 95% CI 1.039-2.912, p = 0.035), and schooling (OR = 2.655, 95% CI 1.338-5.268) were independent risk factors for POD. The association between intraoperative hypotension and POD was significantly influenced by surgery duration (p for interaction = 0.008), with a stronger association in prolonged surgeries (adjusted OR = 4.902; 95% CI 1.816-13.230).

CONCLUSIONS

Intraoperative hypotension and low education level are associated with an increased risk of POD in elderly male patients undergoing laryngectomy, especially with prolonged surgery duration.

Effects of Remimazolam on Intraoperative Frontal Alpha Band Power Spectrum Density and Postoperative Cognitive Function in Older Adults Undergoing Lower Extremity Fractures Surgeries: A Randomized Controlled Trial

Purpose

Low density of electroencephalogram alpha band power was reported to be associated with perioperative cognitive dysfunction. Few studies have conducted to explore the effects of remimazolam on intraoperative frontal alpha band power spectrum density in older adults. Here, we aimed to explore the impact of remimazolam on intraoperative frontal brain wave alpha band activity and postoperative cognitive function in older adults undergoing lower extremity fractures surgeries.

Methods

Patients undergoing elective general anesthesia for lower extremity fracture surgery were randomly allocated to remimazolam group (Group R) and midazolam group (Group M). Group R was induced with remimazolam bolus 0.1 mg/kg followed by a maintenance dose of 0.1 mg·kg-1·h-1 for general anesthesia. Group M was induced with midazolam 0.05 mg/kg followed by normal saline maintenance of 0.1 mL·kg-1·h-1. The rest anesthesia protocol was the same for both groups. Electroencephalogram data was recorded before anesthesia induction till the end of surgery. Cognitive function was assessed preoperatively, and at the first, third, fifth, and seventh day postoperatively.

Results

Compared with Group M, Group R had significantly higher intraoperative power spectral density of the frontal alpha band (P < 0.001), and significantly lower incidence of postoperative cognitive dysfunction at T8 and T9 (P = 0.031 and P = 0.017, respectively).

Conclusion

Remimazolam can increase frontal brain wave alpha band power spectrum density and improve postoperative cognitive function in older adults undergoing lower extremity fractures surgeries.

Determining influences of intraoperative s-ketamine on postoperative delirium and cognitive function: methodology is important

The letter to the editor was written in response to the recent article by Wang et al. "The influence of low-dose s-ketamine on postoperative delirium and cognitive function in older adults undergoing thoracic surgery", which is published in Journal of Cardiothoracic Surgery. 2024; 19(1):324. This article concludes that intravenous low-dose S-ketamine during thoracic surgery in older patients significantly reduces the incidences of postoperative delirium and cognitive dysfunction, indicating a potential neuroprotective effect of intraoperative low-dose S-ketamine. In view to the retrospective nature of this study and their inconsistent findings with the results of a recent randomized controlled trial performed in patients undergoing non-cardiac thoracic surgery, we believe that several methodological issues and potential confounders in this study deserve further clarification and discussion before accepting their conclusions. Our main concerns include lacking the times and number of delirium monitoring per postoperative day, alone use of the Confusion Assessment Method form for delirium screening, not providing the factors related to the occurrence of postoperative delirium in the ICU stay, and application of a non-standard definition for postoperative cognitive impairment. We believe that clarification of these issues is useful for improving the transparency of their methodology and facilitating the interpretation of their results.

Effects of glucocorticoids on postoperative delirium in patients undergoing elective non-cardiac surgery:A systematic review and meta-analysis

Background

Postoperative delirium (POD) is common postoperative complications in non-cardiac surgery. While delirium prophylaxis has not yielded unequivocal support. The clinical effects of glucocorticoids on POD remains unclear.

Objective

To evaluate the effects of glucocorticoids on postoperative delirium (POD) in patients undergoing non-cardiac surgery.

Design

Systematic review with meta-analysis.

Methods

In strict accordance with the PRISMA statement, a systematic literature search was undertaken across PubMed, EMBASE, Web of Science and Cochrane Library databases in May 2023. We updated the search results on June 28, 2024. We used the Grading of the Recommendation Assessment, Development, and Evaluation (GRADE) system to evaluate the quality of evidence.

Results

This meta-analysis included twelve randomized controlled trials involving 1044 participants undergoing non-cardiac surgery. Compared with the control group, glucocorticoids significantly reduced the incidence of POD in patients undergoing non-cardiac surgery (RR:0.50, 95%CI:0.41 to 0.60, P < 0.00001, I2 = 26 %, GRADE = high). Meanwhile, glucocorticoids was associated with reducing the severity of POD (RR: -0.67, 95%CI: -1.10 to -0.23, P = 0.003, I2 = 89 %, GRADE = low). However, there were no significant differences with regards to patients receiving antipsychotic drug (RR: 0.91, 95%CI:0.43 to 1.92, P = 0.80, I2 = 0 %, GRADE = moderate), length of hospital stay (RR: -0.52, 95%CI: -1.41 to 0.36, P = 0.24, I2 = 0 %, GRADE = moderate), 30-day postoperative mortality (RR: 0.70, 95%CI:0.23 to 2.15, P = 0.54, I2 = 0 %, GRADE = low) and postoperative infection (RR: 0.87 95%CI: 0.58 to 1.30, P = 0.50, I2 = 33 %, GRADE = moderate).

Conclusions

This systematic review and meta-analysis suggests that glucocorticoids reduce the incidence of POD among adults and children undergoing non-cardiac surgery and mitigate the severity of POD in adults, which indicates that glucocorticoids exhibit preventive or therapeutic effects on POD.

Registration

CRD42023426836 (PROSPERO).

Systematic literature review on early detection of postoperative delirium in adult patients after cardiac surgery

BACKGROUND

Postoperative delirium (POD) is a cognitive decline and attention deficit that can occur in patients after cardiac surgery. Despite extensive research identifying the risk factors, POD often remains undiagnosed and untreated in medical settings. Therefore, this systematic literature review (SLR) aimed to summarize the available studies on early POD identification in patients following cardiovascular surgery.

METHOD

Data were obtained from Scopus, PubMed, and the Cochrane International database. The search strategy was designed to identify articles published between January 2000 and January 2024. The keywords and medical subject heading (MeSH) terms used in the search included "postoperative delirium," "cardiac surgery," "early detection," and "risk factors." Studies were included if they met the following criteria: (1) focused on adult patients undergoing cardiac surgery; (2) examined methods for the early identification or prediction of POD; and (3) provided statistical analyses or clinical outcomes related to POD. The exclusion criteria were: studies on non-cardiac surgeries, pediatric populations, or those without clear methodological details.

RESULTS

Seven of the examined studies highlighted high-risk variables (individual characteristics, underlying diseases, and treatment methods) and typical symptoms as crucial components for early POD diagnosis. However, the diagnostic criteria and evaluation methodologies needed to be more consistent, and there was no consensus regarding the most efficient early detection approaches.

CONCLUSION

These findings underscore the need for standardized diagnostic criteria and evaluation methods for the early detection of POD in patients undergoing cardiovascular surgery. Evidence-based recommendations are necessary to enhance early diagnosis and treatment of POD in this population.

The Impact of Non-Pharmacological Sleep Interventions on Delirium Prevention and Sleep Improvement in Postoperative ICU Patients: A Systematic Review and Network Meta-Analysis

OBJECTIVES

Analyze the effectiveness of different non-pharmacological sleep interventions in preventing delirium among postoperative ICU patients.

RESEARCH METHODOLOGY

We conducted a comprehensive search on PubMed, Cochrane Library, Web of Science, Embase, CINAHL, OpenGrey and reference lists up to May 2024.

SETTING

We systematically searched all randomized controlled trials related to non-pharmacological sleep interventions for the prevention of delirium.

RESULTS

The results of the network meta-analysis showed that, compared to Usual Care, multicomponent interventions are the most effective measures for preventing delirium in postoperative ICU patients (RR = 0.32, 95 % CI = 0.20 to 0.51). This is followed by non-pharmacological sleep interventions aimed at stress relief (RR = 0.60, 95 % CI = 0.41 to 0.89) and circadian rhythm (RR = 0.61, 95 % CI = 0.39 to 0.96). Additionally, non-pharmacological sleep interventions focusing on circadian rhythm demonstrated an improvement in sleep quality among postoperative ICU patients (SMD = -0.99, 95 % CI = -1.88 to -0.11).

CONCLUSIONS

Our study found that multicomponent non-pharmacological sleep interventions are effective in reducing the incidence of delirium in postoperative ICU patients. Furthermore, non-pharmacological interventions focused on circadian rhythm regulation significantly enhance sleep quality among these patients.

IMPLICATIONS FOR CLINICAL PRACTICE

Based on this study, intensive care units and nursing staff have an opportunity to implement the most effective non-pharmacological sleep interventions to prevent delirium and improve sleep quality in postoperative ICU patients. This could contribute to a reduction in the incidence of delirium in postoperative ICU patients.

The effectiveness of postoperative delirium prevention, diagnosis, and intervention protocol in patients monitored in the intensive care unit after cardiac surgery: a quasi-experimental study

BACKGROUND

The incidence of delirium is high in the intensive care unit (ICU) after cardiac surgery. The development of evidence-based care protocols for delirium management and training of nurses in this regard can ensure effective management of delirium. This quasi-experimental study aimed to assess the effectiveness of a postoperative delirium prevention, diagnosis, and intervention protocol in patients undergoing monitoring in the ICU after cardiac surgery.

METHODS

This study included 64 patients who underwent cardiac surgery and met the inclusion criteria, along with 14 nurses working in the ICU. Patients were divided into control (n = 32) and intervention (n = 32) groups. The study comprised three phases: determining the incidence of delirium in the control group and the delirium diagnosis status of the nurses; providing training to nurses on postoperative delirium prevention, diagnosis and intervention protocol; implementing a preliminary study of the protocol; and finally, implementing the protocol in the intervention group. Statistical significance was set at p < 0.05.

RESULTS

While there was no significant agreement in delirium diagnosis between researcher and nurses in the control group (kappa: 0.207) (p > 0.05), significant agreement was observed in the intervention group (kappa: 1.00) (p < 0.001). The delirium diagnosis rate of the nurses was 14.3% in the control group and 100% in the intervention group, which was a significant difference. The incidence of delirium was 21.9% in the control group and 9.4% in the intervention group, although the difference was not significant.

CONCLUSION

Postoperative delirium prevention, diagnosis, and intervention protocol effectively enhance delirium diagnosis compliance among researchers and nurses and improve the accuracy of delirium diagnosis among postcardiac surgery ICU patients. The implementation of this protocol is recommended for delirium management in such patients.

TRIAL REGISTRATION

This study was retrospectively registered at Clinicaltrials.gov on 19.02.2024 (Clinical Trials ID: NCT06268119).

Sex-Specific Validity of the PRE-DELIRIC Model and the E-PRE-DELIRIC Model for Predicting Delirium in Patients After Cardiac Surgery

BACKGROUND

Several risk prediction models are used in intensive care units (ICUs) to detect delirium risk.

OBJECTIVE

The aim of this study was to compare the sex-specific validity of the Prediction of Delirium in ICU patients (PRE-DELIRIC) and Early Prediction of Delirium in ICU patients (E-PRE-DELIRIC) models for predicting delirium in ICU patients after cardiac surgery.

METHODS

Retrospective data from electronic medical records of ICU patients who underwent cardiac surgery between January 2019 and December 2022 were examined. Both models were evaluated using sensitivity, specificity, and positive and negative predictive values based on the highest Youden index for female and male patients. Receiver operating characteristic curve analysis was performed.

RESULTS

Delirium incidence was 30.7% and 27.5% in female and male patients, respectively. In the PRE-DELIRIC model, the highest Youden index scores for female and male patients were 67.00 and 57.54, respectively, with sensitivities and specificities of 61% and 88%, and 72% and 79%, respectively. In the E-PRE-DELIRIC model, the highest scores for female and male patients were 14.25 and 14.05, with sensitivities and specificities of 78% and 50%, and 70% and 53%, respectively. The area under the curve of the PRE-DELIRIC model for female and male patients was 0.77 and 0.78, respectively, and that of the E-PRE-DELIRIC model was 0.67 and 0.63, respectively.

CONCLUSIONS

The PRE-DELIRIC model showed higher specificity and was more reliable for male patients, whereas the E-PRE-DELIRIC model demonstrated better sensitivity for female patients due to its inclusion of more female-sensitive factors. A combined approach is recommended for improved reliability and validity in delirium risk assessment in clinical settings.

Risk Factors and Pain Management in the Incidence of Postoperative Delirium in Elderly Patients: A Retrospective Study

Background: Postoperative delirium (POD) is a common surgical complication that increases hospital stay duration, hospitalization costs, readmission rates and mortality. This study aims to describe the incidence of POD in an elderly patient population and to investigate pain assessment as a risk factor for postoperative confusion. Additionally, we aim to determine a predictive model for POD. Methods: We conducted a retrospective, observational, single-center study at La Timone Hospital between September 2020 and September 2021. We included patients aged 65 or older, admitted for scheduled or emergency surgical care, with an expected postoperative stay of three days or more and no history of dementia. Data were collected in three stages of hospitalization: preoperative, perioperative, and postoperative. Preoperative data included medical history and lifestyle; perioperative data included surgical and anesthesia characteristics, and postoperative data were collected. Results: Of the 531 patients admitted for surgical care, we analyzed 109 patients. Among these, 24 (22%) experienced a POD episode within the first three postoperative days. Age, preoperative cognitive impairments, preoperative sensory deficits, and long-term benzodiazepine use were identified as risk factors for POD. A significant difference in pain levels was also observed for all NRS scores during the first three postoperative days. After multivariate analysis, we retained two predictive models for POD. Conclusions: This study identified risk factors for POD and proposed predictive models based on these factors. Two models were particularly notable for their potential use in anesthesia consultations and patient follow-up services to quickly detect patients at risk of POD.

Disorientation as a delirium feature in non-intubated patients: development and evaluation of diagnostic accuracy of the 'Confusion Assessment Method for Intermediate Care Unit' (CAM-IMC) - a prospective cohort study

BACKGROUND

Disorientation is an early indicator of developing postoperative delirium (POD), which is associated with increased mortality and cognitive decline. The well-established "Confusion-Assessment-Method-for-Intensive-Care-Unit" (CAM-ICU) for diagnosing POD in intubated patients cannot make use of the feature 'disorientation', as this requires verbal communication. Other tools such as the 4AT test for disorientation but are not established in ICU settings. We therefore combined test-variables of the CAM-ICU (level of consciousness, fluctuating mental status and inattention) with verbal testing for disorientation to develop and enhance diagnostic accuracy of the "Confusion Assessment Method for Intermediate Care Unit" (CAM-IMC). In the present study we describe the development and the evaluation of the diagnostic accuracy of the CAM-IMC.

METHODS

We conducted a prospective cohort-study to develop and evaluate the diagnostic accuracy of the CAM-IMC and disorientation for diagnosing POD in non-intubated patients undergoing elective cardiac surgery. All patients were eligible during data collection period. Exclusion criteria were preexisting brain-organic disease, age < 50 years, preoperative intubation, and insufficient language skills. Patients were assessed for POD using the CAM-IMC as the index-test by two independent examiners over three postoperative days. Reference-testing was conducted by experienced reference-raters. The primary outcome was the diagnostic test-performance.

RESULTS

Among 178 eligible patients, 624 paired observations were completed with 155 patients. Of these, 9% experienced POD. Sensitivity and specificity were 0.96 (CI-95%: 0.87-1.00) and 0.94 (CI-95%: 0.92-0.96), respectively. Area-Under-the-Receiver-Operating-Characteristic-Curve (AUROC; equivalent to c-statistic) for CAM-IMC with a cut-off at three points was 0.95 (CI-95%: 0.93-0.98). The interrater reliability was 0.80 (CI-95%: 0.69-0.91).

CONCLUSION

The CAM-IMC demonstrates excellent test performance for diagnosing POD in non-intubated patients by combining features of the CAM-ICU with 'disorientation'. Given an aging community with an increasing delirium risk, the CAM-IMC provides a highly structured assessment tool for POD. It enables early and accurate detection of delirium, which is critical for timely intervention and improved patient outcomes. The CAM-IMC appears to be a useful tool to be implemented in units for not-intubated patients and seems to be the perfect match where the CAM-ICU is already in use for monitoring POD.

TRIAL REGISTRATION

DRKS00026980 (German registry of clinical studies).

The Prediction of Postoperative Delirium Using the Preoperative Assessments of Frailty and Cognitive Impairment in Aged Patients

Purpose

Frailty and cognitive impairment are closely associated with postoperative delirium. The purpose of this study was to compare the ability of screening tools assessing preoperative frailty and cognitive impairment to predict Postoperative delirium (POD) and the association with prevalence of postoperative complications, Intensive Care Unit (ICU) admission, and the hospital length of stay.

Patients and Methods

Two hundred and ninety-nine patients aged ≥60 years presenting for elective major thoracic or abdominal surgery were divided into preoperative frailty and no frailty groups or cognitive impairment and no cognitive impairment groups. The primary outcome was the incidence of postoperative delirium. The secondary outcomes included postoperative complications, ICU admission, and hospital lengths of stay.

Results

Frailty (25.6% VS 14.6%, P = 0.017) and cognitive impairment (32.7% VS 13.4%, P < 0.001) were associated with POD. However, the area under the receiver operating characteristic curve (AUC-ROC) between frailty (0.657 [95% CI 0.60-0.71]) and cognitive impairment (0.661 [95% CI 0.60-0.71]) for POD was not different (P = 0.9) and both lower than the integrated predictive model of age, body mass index (BMI), American Society of Anesthesiologists (ASA) status, duration of surgery, morphine equivalent, surgical risk, frailty and cognitive impairment (0.814 [95% CI 0.77-0.86], P < 0.0001, P < 0.0001). Besides, frailty (15.6% vs 6.3%, P = 0.010) and cognitive impairment (16.3% vs 8.0%, P = 0.029) was associated with the incidence of postoperative complications.

Conclusion

Preoperative frailty and cognitive impairment were associated with POD. However, preoperative frailty or cognitive impairment by themselves were comparably poor predictors of POD. A comprehensive predictive model including age, BMI, ASA status, duration of surgery, morphine equivalent, surgical risk, frailty and cognitive impairment was more useful to predict POD.

Optimization of the cardiac delirium index by including age, decrease in butyrylcholinesterase actitivity, preoperative HbA1c, and postoperative hemoglobin levels: results of a secondary analysis of a prospective observational study

Introduction

Postoperative delirium (POD) after cardiac surgery significantly affects the perioperative morbidity and mortality. Butyrylcholinesterase (BChE) is an enzyme primarily produced in the liver, which plays a crucial role in the hydrolysis of acetylcholine outside of neuronal synapses, referred to as extraneuronal hydrolysis. The integration of BChE activity into the cardiac delirium (CARDEL) index might increase its predictive power for identifying POD after cardiac surgery. Therefore, the primary aim of this study was to assess the applicability of the CARDEL index and determine whether integrating the BChE activity enables optimization of the predictive model.

Methods

This secondary analysis of a prospective observational study included patients undergoing elective coronary artery bypass graft surgery. BChE activity is expressed in units per liter (U/L), while the BChE drop refers to the percentage decrease in BChE activity from pre- to postoperative levels. POD risk factors were identified using multivariate regression analysis. The predictive power of the CARDEL index and an optimized model including BChE was calculated with receiver operating characteristic (ROC) analysis.

Results

Of 93 included patients, 20 (21.5%) developed POD. Elevated preoperative HbA1c [OR 2.5 (1.2-4.8), p = 0.01], a decrease in BChE activity [%, OR 1.1 (1.0-1.2), p = 0.04], age [1 (0.94-1.1), p = 0.55], and a postoperative hemoglobin change [OR 0.86 (0.78-0.96), p < 0.001] were identified as independent risk factors for POD. While the CARDEL index showed a moderate prediction of POD [AUCROC of 0.74 (0.60-0.87)], the optimization including BChE resulted in a significant prognostic improvement: AUCROC of 0.84 (0.72-0.94, p < 0.001).

Conclusion

Despite the small size of this derivation cohort, this study identified elevated HbA1c as the strongest risk factor for the development of POD, followed by a decrease in BChE activity, postoperative anemia, and age, respectively. By including these parameters to the CARDEL index, its predictive power for the identification of POD significantly improved in this derivation cohort. Moving forward, integrating these findings into clinical practice could enhance early risk stratification and targeted intervention for patients at high risk of POD. Therefore, further research should evaluate these results in a larger, external cohort.

Relevance of Preoperative Cognitive Impairment for Predicting Postoperative Delirium in Surgical Medicine: A Prospective Cohort Study

BACKGROUND

Post-operative delirium is a dreaded complication after surgery in older patients. The identification of risk factors for delirium and comprehensive geriatric assessment is an extensive part of recent research. However, the preoperative assessment of risk factors, such as impaired cognition, is frequently not standardized.

METHODS

A comprehensive preoperative assessment was performed in 421 surgical patients to investigate the impact of preoperative cognitive impairment (PCI) on the risk of delirium and to evaluate appropriate screening tools (Six-item screener (SIS) and clock-drawing test (CDT)).

RESULTS

Both screening tools showed a significantly increased risk of delirium with p < 0.001 (OR 12.5, 95% [6.42; 24.4]) in SIS and p = 0.042 (OR 2.02, 95%CI [1.02; 4.03]) in CDT for existing cognitive impairment. A higher level of care (p < 0.001) and statutory care (p < 0.001, OR 5.42, 95%CI [2.34; 12.6]) also proved to be significant risk factors. The ROC curves of the two tests show AUC values of 0.741 (SIS) and 0.630 (CDT). The COP values for the SIS are 4 points with a Youden index of 0.447; for the CDT, the COP is 2 (Youden index = 0.177).

CONCLUSIONS

The recording of PCI should be a central component of the preoperative geriatric assessment. The tools used are simple yet effective and can be easily implemented in routine clinical practice. By reliably identifying patients at risk, the available resources can be personalized and used in a targeted approach.

Association between oxidative stress and postoperative delirium in joint replacement using diacron-reactive oxygen metabolites and biological antioxidant potential tests

Postoperative delirium (POD) is a significant complication of surgery that most severely affects older adults and patients with cognitive impairment. This study investigated the relationship between POD and oxidative stress, hypothesizing that increased oxidative stress, measured using diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) tests, is associated with the incidence of POD. This prospective cohort study, involving female patients who underwent unilateral or bilateral joint replacement, was conducted at the Osaka University Graduate School of Medicine from June 2022 to July 2023. Blood samples were collected preoperatively and postoperatively to measure oxidative stress markers using the REDOXLIBRA system. The primary endpoint was the association between changes in oxidative stress markers and the occurrence of POD as diagnosed using the Confusion Assessment Method for the Intensive Care Unit and Richmond Agitation-Sedation Scale. Of the 144 patients screened, 60 were eligible, of which 5 developed POD (8.3%). Analysis of oxidative stress markers revealed no significant changes between preoperative and postoperative values of d-ROMs (mean increase + 6.3 ± 54.2 U CARR) and BAP (mean decrease - 37.4 ± 322.9 µM) tests, or BAP/d-ROMs ratio (mean decrease - 0.4 ± 1.7). Further, no significant differences were observed in oxidative stress markers between patients who underwent unilateral and bilateral procedures. However, patients with POD exhibited a significantly higher increase in d-ROMs than those without complications (p = 0.015), whereas changes in BAP and BAP/d-ROM ratios were not statistically significant. Although general oxidative stress markers do not significantly change postoperatively, increased d-ROM levels are associated with POD occurrence, indicating that oxidative stress could be a contributing factor to its development. This study underscores the need for further research into specific oxidative markers that may predict POD and guide the development of targeted interventions to prevent this debilitating condition.Trial registration Name of the registry Association Between Changes in Blood Oxidative Stress and Postoperative Delirium Following Joint Replacement Surgery: A Retrospective Study. Trial registration number 22021. Date of registration 6/29/2022. URL of trial registry record https://bvits.dmi.med.osaka-u.ac.jp/esct/Apply/project.aspx?PROJECT_ID=6987 .

Brain health: A concern for anaesthesiologists and intensivists

Damage to the brain can have disastrous and long-lasting consequences. The European Society of Anaesthesiology and Intensive Care (ESAIC) is aware of the importance of taking good care of the brain, both of patients and of anaesthesia and intensive care unit (ICU) caregivers, and has organised a complete learning track on brain health to bring this concern to the attention of practitioners. This learning track included an online Focus Meeting on Brain Health (November 25, 2023). We here provide readers with a digest of the information that was delivered during that meeting in an opinion paper driven by the authors' own reading of the literature. It is divided according to the meeting's sessions, including how to improve the health of an injured brain, how to keep a young or old brain healthy, how to keep a healthy adult brain unimpaired, how monitoring can impact brain health in the operating room and in the intensive care unit, and how to keep the anaesthesia and ICU caregivers' brain healthy. Each part is a brief and focused summary. The main delivered messages are that the management of injured brain patients involves an adequate choice of sedation, adequate brain monitoring, and focused attention to specific points depending on the underlying pathology; that several measures can be undertaken to protect the brain of the very young needing anaesthesia; that it is possible to detect older patients at risk of postoperative neurocognitive disorders, and that dedicated perioperative management by a multidisciplinary expert team may improve their outcomes; that apparently healthy adult brains may suffer during anaesthesia; that the electroencephalogram may track peri-operative brain dysfunction, and that female patients should be given special care in this respect; that multimodal brain monitoring helps to detect pathological processes and to maintain brain homeostasis; and that burnout in anaesthesiologists can be effectively fought using personal, organisational, managerial and legal approaches.

Pharmacological Prevention of Postoperative Delirium in Adults: A Review of Recent Literature

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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.

Overcoming age: Slow anesthesia induction may prevent geriatric patients from developing burst suppression and help developing intraoperative EEG signatures of a younger brain

Elderly patients are prone to develop postoperative neurocognitive deficits potentially precipitated by inadequate anesthetic management. To investigate the potential of EEG-guided individualized anesthetic titration we evaluated the effect of the patient's age on the spectral composition of the EEG during slow propofol induction. Twenty-six young (<65 years) and 25 old (≥65 years) patients received propofol until loss of responsiveness (LOR). After LOR, we switched from a flow rate-based to a target-controlled infusion mode keeping the calculated effect-site concentration at LOR stable. We recorded a frontal EEG and calculated the power spectral density (PSD) and the band powers. For the comparison of the spectral composition of old and young patients, we used an effect size, the area under the receiver operating characteristic curve. The older patients received significantly less propofol (p < 0.001). No patient showed a burst suppression pattern. Whereas the absolute power in all frequency bands decreased significantly with the patient's age, the spectral composition did not change throughout the extended induction period. Slow anesthesia induction may be a suitable approach for geriatric patients to preserve spectral composition patterns typically found in younger brains and to individually identify anesthetic requirements reducing the risk of excessive anesthetic effects.

Retrospective comparison of the effects of remimazolam and dexmedetomidine on postoperative delirium in elderly patients undergoing orthopedic surgery of the lower extremities under spinal anesthesia

PURPOSE

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.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

Applying a transformer architecture to intraoperative temporal dynamics improves the prediction of postoperative delirium

BACKGROUND

Patients who experienced postoperative delirium (POD) are at higher risk of poor outcomes like dementia or death. Previous machine learning models predicting POD mostly relied on time-aggregated features. We aimed to assess the potential of temporal patterns in clinical parameters during surgeries to predict POD.

METHODS

Long short-term memory (LSTM) and transformer models, directly consuming time series, were compared to multi-layer perceptrons (MLPs) trained on time-aggregated features. We also fitted hybrid models, fusing either LSTM or transformer models with MLPs. Univariate Spearman's rank correlations and linear mixed-effect models establish the importance of individual features that we compared to transformers' attention weights.

RESULTS

Best performance is achieved by a transformer architecture ingesting 30 min of intraoperative parameter sequences. Systolic invasive blood pressure and given opioids mark the most important input variables, in line with univariate feature importances.

CONCLUSIONS

Intraoperative temporal dynamics of clinical parameters, exploited by a transformer architecture named TRAPOD, are critical for the accurate prediction of POD.

Risk of sarcopenia, frailty and malnutrition as predictors of postoperative delirium in surgery

BACKGROUND

The risk factors for postoperative delirium are numerous and complex. One approach to identifying patients at risk is to evaluate their nutritional status. The aim of this prospective study is to better understand nutrition as a potential risk factor for postoperative delirium.

METHODS

A comprehensive preoperative assessment (Clinical Frailty Scale (CFS), the SARC-F questionnaire, Mini Nutritional Assessment-Short Form (MNA-SF)) were carried out as a prospective clinical study on 421 patients (70+) from 4 different surgical disciplines. Postoperatively, patients are examined daily for the presence of delirium using the 4AT screening tool (Arousal, Attention, Abbreviated Mental Test - 4, Acute change), the Nursing Delirium Screening Scale (NuDesc) and the Confusion Assessment Method (CAM) with its adaptation for the intensive care unit (CAM-ICU).

RESULTS

If there were indications of frailty or sarcopenia in the CFS or SARC-F, the association with delirium was increased 5.34-fold (OR of 5.34 [95% CI: 2.57;11.1]) and 5.56-fold (OR of 5.56 [95% CI: 2.97;10.4]) respectively. Delirium also occurred significantly more frequently with the risk of malnutrition or manifest malnutrition (MNA-SF) than with a normal nutritional status.

CONCLUSIONS

Patients' preoperative and nutritional status significantly impact the risk of developing postoperative delirium. Factors such as frailty, sarcopenia and possible malnutrition must be considered when implementing an effective and targeted preoperative assessment.

TRAIL REGISTRATION

German Clinical Trials Registry at https://www.drks.de/DRKS00028614 , Registered 25 March 2022.

Effect of Low-Dose Esketamine on Postoperative Delirium in Elderly Patients Undergoing Total Hip or Knee Arthroplasty: A Randomized Controlled Trial

Purpose

Postoperative delirium (POD) is a prevalent and severe complication in elderly patients undergoing major surgery, associated with increased morbidity and mortality. This randomized controlled trial aimed to investigate the effects of low-dose esketamine on the incidence of POD in elderly patients underwent total hip or knee arthroplasty.

Patients and Methods

Two hundred and sixty elderly participants were randomly assigned to either the esketamine group (Group E) (0.20mg/kg loading, 0.125mg/kg/h infusion, 0.5 mg/kg for postoperative analgesia) or the placebo group (Group P) (received normal saline). The primary outcome was the incidence of POD, with secondary outcomes including delirium subtypes, duration, intraoperative analgesic consumption, operative and anesthesia times, hemodynamic changes, postoperative pain scores, sleep quality, and common postoperative adverse events.

Results

There was no significant difference in the incidence of POD between Group E (8.5%) and Group P (10.8%). No significant differences were observed for the time of delirium onset, duration of delirium, and delirium subtype between the two groups. Patients in the esketamine group had more stable hemodynamic profile after induction and reduced the pain score of motion on the first two days postoperatively but increased the incidence of postoperative dizziness.

Conclusion

The repeated infusion of low-dose esketamine did not reduce the incidence of POD during the initial three postoperative days in elderly patients following total hip or knee arthroplasty.

Risk factors for delirium occurring after deep brain stimulation surgery in patients with Parkinson's disease

OBJECTIVE

Postoperative delirium (POD) may cause cognitive morbidities and prolonged hospital stay. This study aimed to evaluate the risk factors associated with postoperative delirium in patients undergoing deep brain stimulation (DBS) for Parkinson's disease (PD).

METHOD

We retrospectively reviewed 83 patients with idiopathic PD who underwent bilateral DBS between 2016 and 2023. The target of DBS was the globus pallidus interna (Gpi) or the subthalamic nucleus (STN) in 84.3% and 15.7% of patients, respectively. Patients were evaluated using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and categorized into two groups: those with delirium and those without. Demographic features, disease duration, preoperative cognitive status (Mini-Mental State Examination) and silent ischemia, brain atrophy rates, DBS target location, surgical type and duration, Unified PD Rating Scale-3 scores, Hoehn and Yahr scores, postoperative perilead edema, and electrolyte imbalance were compared between patients with and without post-DBS delirium. Apart from univariate analysis, receiver operating characteristic (ROC) curve analysis for disease duration and multivariate logistic regression analyses were used to determine independent risk factors for post-DBS delirium.

RESULTS

Five out of the 83 patients (6%) developed post-DBS delirium. Age (> 68 years), disease duration, preoperative cerebral atrophy rates, and postoperative perilead edema were significantly higher in patients who developed delirium (p < 0.05 each). The ROC curve analysis revealed disease duration of ≥ 11 years as a risk factor for delirium (p = 0.001; odds ratio, OR: 58.4, 95% confidence interval, CI: 5.45-625.49). Age and disease duration were independent risk factors for post-DBS delirium (OR: 1.243, 95% CI: 1.070-1.592 and OR: 22.52, 95% CI: 1.21-383.96, respectively).

CONCLUSIONS

Older age and longer disease duration are independent risk factors for postoperative delirium in patients with PD. This study highlights the need to identify high-risk patients when undertaking DBS to facilitate early diagnosis and timely management.

Poor sleep quality is a risk factor for adverse clinical outcomes in patients with acute aortic dissection: A prospective cohort study

The decrease in sleep quality leads to an increased risk of cardiovascular disease and is closely related to the prognosis of various diseases. However, the relationship between preoperative sleep quality and postoperative clinical outcomes in patients with acute aortic dissection is still unclear. We aimed to assess the relationship between sleep quality and the clinical outcomes of acute aortic dissection. We assessed participants' sleep quality and the clinical outcomes of acute aortic dissection, which included prolonged mechanical ventilation, postoperative delirium, in-hospital death, continuous renal replacement therapy, intensive care unit stay time, and length of stay. Patients were divided into good sleep quality group (n = 103) and poor sleep quality group (n = 113). Postoperative delirium, in-hospital death, prolonged mechanical ventilation and intensive care unit stay time were significantly increased in the poor sleep quality group when compared with the good sleep quality group (p < 0.05). Multivariate regression analysis showed that the poorer sleep quality, the greater the risk of in-hospital death (odds ratio = 3.451, 95% confidence interval 1.19-10.004) and prolonged mechanical ventilation (odds ratio = 6.302, 95% confidence interval 3.105-12.791), and the longer intensive care unit stay time (β = 62.37, 95% confidence interval 22.411-102.329). In addition, the higher the incidence of smoking history (odds ratio = 7.417, 95% confidence interval 2.425-22.684), poor sleep quality (odds ratio = 11.59, 95% confidence interval 3.844-34.942) and postoperative delirium (odds ratio = 5.1, 95% confidence interval 1.793-14.504), the greater the risk of prolonged mechanical ventilation. Our findings revealed that poor sleep quality may be a risk factor for adverse clinical outcomes of acute aortic dissection. Rapid assessment of self-reported sleep quality may be a simple and effective way to identify patients with acute aortic dissection who are at high risk for prolonged mechanical ventilation.

Automated EEG-Based Brainwave Analysis for the Detection of Postoperative Delirium Does Not Result in a Shorter Length of Stay in Geriatric Hip Fracture Patients: A Multicentre Randomized Controlled Trial

Introduction: Delirium in postoperative geriatric hip fracture patients is a serious and often preventable condition. If detected in time, it can be treated, but a delay in the diagnosis and initiation of treatment impairs outcomes. A novel approach to detect delirium is to use point-of-care electro-encephalogram (EEG) recording with automated analysis. In this study, the authors investigated whether screening for delirium with EEG recording and automated analysis resulted in reduced length of stay after surgery and superior screening performance in comparison to the Delirium Observation Screening Scale (DOS). Methods: This randomized control trial was conducted at two geriatric trauma centres in the Netherlands. Patients were eligible for inclusion if they were aged 70 years or above, were admitted to the geriatric trauma unit and undergoing surgery for a hip fracture. Patients were randomized to either the intervention (EEG-based brainwave analysis) or control group (DOSS screening tool). Participants were screened for delirium twice a day during three consecutive days starting at day 0 of the surgery, with the first measurement before the surgery. The primary outcome was length of stay. In addition, the screening performance for both automated EEG-based brainwave analysis and DOS was determined. Results: A total of 388 patients were included (189 per arm). There were no differences between groups in terms of median hospital length of stay (DOS 7 days (IQR 5.75-9) vs. EEG-based brainwave analysis 7 days (IQR 5-9); p = 0.867). The performance of EEG-based brainwave analysis was considerably lower than that of the DOSS in terms of discrimination between patients with and without postoperative delirium. Conclusions: Screening for postoperative delirium in geriatric hip fracture patients using automated EEG-based brainwave analysis did not result in a shorter length of stay. Additionally, the results of this study show no clear advantage in terms of the screening performance of EEG-based brainwave analysis over the current standard of care for geriatric patients with a hip fracture.

National survey on perioperative cognitive dysfunction

BACKGROUND

Perioperative cognitive dysfunction (PCD) is a very prevalent clinical syndrome due to the progressive aging of the surgical population.The aim of our study is to evaluate the clinical practice of Spanish anesthesiologists surveyed regarding this entity.

MATERIAL AND METHODS

Prospective online survey conducted by the Neurosciences Section and distributed by SEDAR.

RESULTS

544 responses were obtained, with a participation rate of 17%. 54.4% of respondents never make a preoperative assessment of cognitive impairment, only 7.5% always do it. 79.6% lack an intraoperative management protocol for the patient at risk of PCD. In the anesthetic planning, only 23.3% of the patients was kept in mind. Eighty-nine percent considered regional anesthesia with or without sedation preferable to general anesthesia for the prevention of PCD. 88.8% considered benzodiazepines to present a high risk of PCD. 71.7% considered that anesthetic depth monitoring could prevent postoperative cognitive deficit. Routine evaluation of postoperative delirium is low, only 14%. More than 80% recognize that PCD is underdiagnosed.

CONCLUSIONS

Among Spanish anesthesiologists surveyed, PCD is still a little known and underappreciated entity. It is necessary to raise awareness of the need to detect risk factors for PCD, as well as postoperative assessment and diagnosis. Therefore, the development of guidelines and protocols and the implementation of continuing education programs in which anesthesiologists should be key members of multidisciplinary teams in charge of perioperative care are suggested.

Sex Differences in Delirium after Coronary Artery Bypass Graft Surgery and Perioperative Neuropsychiatric Conditions: A Secondary Analysis of a Cohort Study

BACKGROUND

Biological sex influences the risk of depression and cognitive impairment, but its role in relation to postoperative delirium is unclear. This analysis investigates sex differences in delirium risk after coronary artery bypass graft (CABG) surgery and sex-related differences in relation to affective and cognitive symptoms.

METHODS

This is a secondary analysis of the Neuropsychiatric Outcomes After Heart Surgery (NOAHS) study, a single-site, observational study of a CABG surgery cohort (n = 149). Preoperative characteristics are stratified by sex, and baseline variables that differ by sex are evaluated to understand whether sex modifies their relationships with delirium. We also evaluate sex differences in one-month depression and cognition.

RESULTS

Female sex is associated with several delirium risk factors, including higher risk of preoperative depression and middle cerebral artery (MCA) stenosis. MCA stenosis was statistically associated with delirium only among women (OR 15.6, 95% CI 1.5, 164.4); mild cognitive impairment (MCI) was associated with delirium only in men (OR 4.6, 95% CI 1.2, 17.9). Other sex-based differences failed to reach statistical significance. Depression remained commoner among women 1 month post-CABG.

CONCLUSIONS

Women in this CABG cohort were more likely to have depression at baseline and 1 month postoperatively, as well as MCA stenosis and postoperative delirium. Sex might modify the relationship between post-CABG delirium and its risk factors including MCA stenosis and MCI. Cerebrovascular disease deserves study as a potential explanation linking female sex and a range of poor outcomes among women with coronary heart disease.

Intranasal Dexmedetomidine-Esketamine Combination Premedication versus Monotherapy for Reducing Emergence Delirium and Postoperative Behavioral Changes in Pediatric Tonsillectomy and/or Adenoidectomy: A Randomized Controlled Trial

Purpose

Emergence delirium and postoperative negative behavioral changes (PNBC) are common complications in pediatric anesthesia. This study evaluated whether intranasal premedication combining dexmedetomidine and esketamine more effectively reduces these complications compared to either drug alone in children undergoing tonsillectomy and/or adenoidectomy with sevoflurane anesthesia.

Patients and Methods

This randomized, double-blind trial involved 198 children aged 2-5 years undergoing tonsillectomy and/or adenoidectomy. Participants received intranasal premedication with either dexmedetomidine (2 μg/kg), esketamine (1 mg/kg), or their combination (dexmedetomidine 1 μg/kg plus esketamine 0.5 mg/kg). The primary outcome was the incidence of emergence delirium, defined as a Pediatric Anesthesia Emergence Delirium (PAED) scale score ≥ 10. Secondary outcomes included the incidence of PNBC, sedation depth, easiness of separation from parents, acceptance of the mask for induction, emergence time, postoperative pain score, parental satisfaction, and adverse events.

Results

The combination premedication significantly reduced emergence delirium incidence (9.4%) compared to esketamine alone (38.1%; relative risk [RR] 0.25, 95% confidence interval [CI] 0.11-0.57, p < 0.001), but not compared to dexmedetomidine alone (17.2%; RR 0.55, 95% CI 0.21-1.39, p = 0.193). PNBC incidence at day 7 was lower with the combination (28.1%) versus dexmedetomidine (48.4%; RR 0.58, 95% CI 0.36-0.93, p = 0.018), but not significantly different from esketamine alone (20.6%; RR 1.38, 95% CI 0.74-2.58, p = 0.326). The combination also provided significantly superior sedation, improved ease of separation from parents, better acceptance of the mask for induction, shorter emergence time, and higher parental satisfaction than both monotherapies.

Conclusion

In children undergoing tonsillectomy and/or adenoidectomy with sevoflurane anesthesia, intranasal dexmedetomidine-esketamine premedication more effectively reduces emergence delirium compared to esketamine alone and PNBC compared to dexmedetomidine alone. This combination also improves sedation, shortens emergence times, and enhances parental satisfaction compared to monotherapy without significant adverse effects.

Trial Registration

The Chinese Clinical Trial Registry, ChiCTR2300076709.

Preoperative frailty tendency predicts delirium occurrence in older people undergoing spinal surgery

BACKGROUND

This prospective cohort study focused on the predictive value of frailty or pre-frailty assessed by Edmonton Frailty Scale (EFS) for postoperative delirium in spinal surgery patients.

METHODS

The primary outcome measurement was postoperative delirium (POD) evaluated by Confusion Assessment Method at day 1, day 2, and day 3 after the surgery. Secondary outcomes included severity and duration of POD, severe postoperative pain measured by Faces Pain Scale-Revised. Patients scheduled for elective spinal surgery were enrolled and assessed for frailty by EFS before surgery. Demographic data, preoperative, intraoperative, and postoperative information were collected.

RESULTS

231 out of 325 patients were enrolled and analyzed in this study at last. The cohort with 36.8% being frail and 28.5% being vulnerable. Postoperative delirium was detected in 41 in 231 patients. Multivariate logistic regression analysis revealed that vulnerable to frailty (OR = 4.681, 95% CI: 1.199 to 18.271, P = 0.026), after adjusted duration of surgery more than 3 h, using flumazenil at the end of surgery, using butorphanol only in postoperative patient-controlled intravenous analgesia, moderate-to-severe pain at day 1 and 2, is a strong predictor of postoperative delirium. Frailty was associated with longer duration (frailty vs. fit, P = 0.364) and stronger severity of postoperative delirium in the first two days (P < 0.001). High EFS score was independent risk factor of severe postoperative pain (Frailty vs. Fit: OR = 5.007, 95% CI: 1.903 to 13.174, P = 0.001; Vulnerable vs. Fit: OR = 2.525, 95% CI: 1.008 to 6.329, P = 0.048). In stratified tests, Sufentanil regimen in intravenous PCA significantly increase the proportion of POD in vulnerable group (P = 0.030), instead of frailty group (P = 0.872) or fit group (P = 0.928).

CONCLUSIONS

Frailty can increase the risk, severity, duration of delirium and severe postoperative pain in the first 3 days after surgery of patients.

TRIAL REGISTRATION

The protocol of this study has been approved by the Ethic Committee of Shanghai Changzheng Hospital (Approval file number: 2022SL044) and informed consent was obtained from all the patients. The trial was retrospectively registered at chictr.org.cn (ChiCTR2300073306) on 6th July 2023.

The impact of diurnal variations on emergence delirium following general anesthesia and surgery in children

Background

Emergence delirium (ED) is a widely recognized issue that prolongs mechanical ventilation and post-anesthesia care unit (PACU) resuscitation time, consequently increasing hospital costs and mortality. Postoperative disturbance in circadian rhythms, commonly leading to sleep disorders, has been identified as a significant risk factor for ED. However, the influence of surgery timing (morning vs. afternoon) on the incidence of ED in pediatric patients undergoing general anesthesia remains unknown.

Methods

Patients aged 2-6 years who were operated on under general anesthesia with a bispectral index value between 50 and 60 were categorized based on anesthesia start time into either the morning surgery group (Group M, 8:00-12:00) or the afternoon surgery group (Group A, 13:00-17:00). The primary outcome was the post-extubation incidence of ED assessed by the Cornell Assessment of Pediatric Delirium (CAPD) score. Secondary outcomes included extubation time, duration of PACU stay, and adverse postoperative events and complications.

Results

We recruited a total of 560 patients, 280 in group M and 280 in group A. Compared to Group M, Group A exhibited a significantly higher incidence of ED (p < 0.001), elevated CAPD scores (p < 0.001), and prolonged PACU stays (p < 0.001). Notably, there was no significant difference in extubation time and anesthesia-related adverse events or other postoperative complications between the groups.

Conclusion

Our study highlights that the time of surgery significantly affects the incidence of ED, CAPD scores, and PACU stay duration in children. Further validation of these findings may guide future strategies to reduce ED.

Post-operative delirium in different age groups and subtypes: a systematic review of case reports

Aims

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

Design

Systematic review of Published Cases.

Methods and data sources

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.

Results

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.

Conclusions

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.

Systematic review registration

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

Registered nurses' experiences of caring for patients with hypoactive delirium after cardiac surgery - A qualitative study

OBJECTIVES

Delirium is a common post-cardiac surgery complication that presents as acute changes in mental abilities with confused thinking and a lack of awareness of the surroundings. Delirium symptoms present in hyperactive- and hypoactive forms. Hypoactive delirium is often overlooked. Although nursing interventions are important in preventing and treating hypoactive delirium, studies focusing on nurses' experiences of hypoactive delirium are scarce. This study describes registered nurses' experiences of caring for patients with hypoactive delirium after cardiac surgery.

RESEARCH METHODOLOGY/DESIGN

This was a qualitative descriptive study with an inductive approach. Data was collected through focus group interviews with 12 registered nurses with experience in caring for cardiac surgery patients with hypoactive delirium. The study complied with the Consolidated Criteria for Reporting Qualitative Research.

SETTING

A cardiac surgery department at a Swedish University Hospital.

FINDINGS

The analysis resulted in one main category; "Navigating the complexities of care when caring for patients with hypoactive delirium" and three sub-categories: "Challenges, "Nursing interventions" and "Promoting a team approach".

CONCLUSION

Delirium assessment and nursing interventions are perceived as essential yet demanding. when caring for patients with hypoactive delirium. Nursing interventions like maintaining the circadian rhythm and offering emotional support need to be prioritised by the nurses, in line with the autonomy of the registered nurse's profession. Moreover, the team around the patient is crucial for detecting and treating hypoactive delirium, and it is important to involve other professionals as well as the patient's relatives. Future research is needed to develop assessment instruments that more accurately capture hypoactive delirium in the postoperative setting.

IMPLICATIONS FOR CLINICAL PRACTICE

Despite the use of screening tools, nurses still experience challenges in detecting the symptoms of hypoactive delirium, indicating a need for more clinically effective screening tools for hypoactive delirium. Nursing interventions are emphasised in the care of patients with hypoactive delirium.

Determination of the ED90 of Dexmedetomidine Infusion to Prevent Emergence Agitation in Children Undergoing Dental Rehabilitation With Sevoflurane Anesthesia: A Biased-Coin Up-and-Down Sequential Allocation Trial

BACKGROUND

Emergence agitation (EA) is an adverse complication during early recovery from sevoflurane anesthesia. Continuous intravenous infusion of dexmedetomidine (DEX) is commonly used for EA prevention. However, a wide dose range is used for preventing EA, and the optimal dose remains unknown. This study was aimed at determining the optimal dose (the 90% effective dose [ED90]) of DEX for continuous intraoperative infusion for EA prevention in children.

METHODS

We enrolled children aged 3 to 7 years who underwent dental treatment under sevoflurane anesthesia. DEX was continuously infused from the time of the establishment of the intravenous access until 5 minutes before the end of surgery. The initial DEX dose was 0.5 µg/kg/h, and subsequent dose adjustments were determined based on the response of the previous patient by using an up-down sequential allocation with a biased-coin design. The primary outcome was the ED90 for continuous DEX infusion based on the success or failure of the EA-preventing dose.

RESULTS

Forty-five patients were enrolled in the study. The DEX dose ranged from 0.50 to 0.90 µg/kg/h. The estimated ED90 (95% confidence interval [CI]) for preventing EA was 0.74 µg/kg/h (0.67-1.05 µg/kg/h). The duration of surgery (mean ± standard deviation [SD]) was 113 ± 30 minutes. The times (mean ± SD) for extubation, time to emergence, and recovery time were 5 ± 2 minutes, 27 ± 9 minutes, and 39 ± 7 minutes, respectively.

CONCLUSIONS

The ED90 for continuous intraoperative DEX infusion for EA prevention in pediatric patients receiving dental treatment under sevoflurane anesthesia was 0.74 µg/kg/h (95% CI, 0.67-1.05 µg/kg/h).

Association between Intraoperative Hypotension and Postoperative Delirium: A Retrospective Cohort Analysis

BACKGROUND

Intraoperative hypotension might contribute to the development of postoperative delirium through inadequate cerebral perfusion. However, evidence regarding the association between intraoperative hypotension and postoperative delirium is equivocal. Therefore, the hypothesis that intraoperative hypotension is associated with postoperative delirium in patients older than 70 yr having elective noncardiac surgery was tested .

METHODS

This was a retrospective cohort analysis of patients older than 70 yr who underwent elective noncardiac surgery in a single tertiary academic center between 2020 and 2021. Intraoperative hypotension was quantified as the area under a mean arterial pressure (MAP) threshold of 65 mmHg. Postoperative delirium was defined as a collapsed composite outcome including a positive 4 A's test during the initial 2 postoperative days, and/or delirium identification using the Chart-based Delirium Identification Instrument. The association between hypotension and postoperative delirium was assessed using multivariable logistic regression, adjusting for potential confounding variables. Several sensitivity analyses were performed using similar regression models.

RESULTS

In total, 2,352 patients were included (median age, 76 yr; 1,112 [47%] women; 1,166 [50%] American Society of Anesthesiologists Physical Status III or greater; 698 [31%] having high-risk surgeries). The median [interquartile range] intraoperative area under the curve below a threshold of MAP less than 65 mmHg was 28 [0, 103] mmHg · min. The overall incidence of postoperative delirium was 14% (327 of 2,352). After adjustment for potential confounding variables, hypotension was not associated with postoperative delirium. Compared to the first quartile of area under the curve below a threshold of MAP less than 65 mmHg, patients in the second, third, and fourth quartiles did not have more postoperative delirium, with adjusted odds ratios of 0.94 (95% CI, 0.64 to 1.36; P = 0.73), 0.95 (95% CI, 0.66 to 1.36; P = 0.78), and 0.95 (95% CI, 0.65 to 1.36; P = 0.78), respectively. Intraoperative hypotension was also not associated with postoperative delirium in any of the sensitivity and subgroup analyses performed.

CONCLUSIONS

To the extent of hypotension observed in our cohort, our results suggest that intraoperative hypotension is not associated with postoperative delirium in elderly patients having elective noncardiac surgery.

EDITOR’S PERSPECTIVE