Postoperative Cognitive Decline After Cardiac Surgery: A Narrative Review of Current Knowledge in 2019

Postoperative cognitive disorders and delirium in gynecologic surgery: Which surgery and anesthetic techniques to use to reduce the risk?

Despite their general good health, an increasing proportion of elderly individuals require surgery due to an increase in average lifespan. However, because of their increased vulnerability, these patients need to be handled carefully to make sure that surgery does not cause more harm than good. Age-related postoperative cognitive disorders (POCD) and postoperative delirium (POD), two serious consequences that are marked by adverse neuropsychologic alterations after surgery, are particularly dangerous for the elderly. In the context of gynecologic procedures, POCD and POD are examined in this narrative review. The main question is how to limit the rates of POCD and POD in older women undergoing gynecologic procedures by maximizing the risk-benefit balance. Three crucial endpoints are considered: (1) surgical procedures to lower the rates of POCD and POD, (2) anesthetic techniques to lessen the occurrence and (3) the identification of individuals at high risk for post-surgery cognitive impairments. Risks associated with laparoscopic gynecologic procedures include the Trendelenburg posture and CO2 exposure during pneumoperitoneum, despite statistical similarities in POD and POCD frequency between laparoscopic and laparotomy techniques. Numerous risk factors are associated with surgical interventions, such as blood loss, length of operation, and position holding, all of which reduce the chance of complications when they are minimized. In order to emphasize the essential role that anesthesia and surgery play in patient care, anesthesiologists are vital in making sure that anesthesia is given as sparingly and quickly as feasible. In addition, people who are genetically predisposed to POCD may be more susceptible to the disorder. The significance of a thorough strategy combining surgical and anesthetic concerns is highlighted in this article, in order to maximize results for senior patients having gynecologic surgery.

Incidence and related risk factors for postoperative delirium following revision total knee arthroplasty: a retrospective nationwide inpatient sample database study

BACKGROUND

Postoperative delirium (POD) is a common surgical complication. However, the incidence and risk factors associated with postoperative delirium after revision total knee arthroplasty (rTKA) have not been comprehensively explored through extensive national databases.

METHODS

Utilizing the National Inpatient Sample (NIS), the largest comprehensive U.S. hospital healthcare database, we undertook a retrospective investigation involving 127,400 patients who underwent rTKA between 2010 and 2019. We assessed various aspects, including patient demographics, hospital characteristics, pre-existing medical conditions, and perioperative complications.

RESULTS

The overall incidence of postoperative delirium (POD) in patients undergoing rTKA between 2010 and 2019 was 0.97%. The highest incidence rate of 1.31% was recorded in 2013. Notably, this patient cohort demonstrated advanced age, increased burden of co-morbidities, prolonged hospital stays, increased hospitalization costs, and elevated in-hospital mortality rates (P < 0.001). Moreover, non-elective admissions, non-private insurance payments, and a preference for teaching hospitals were commonly observed among these patients. During their hospitalization, individuals who developed delirium subsequent to rTKA were more prone to experiencing certain perioperative complications. These complications encompassed medical issues like acute myocardial infarction, continuous invasive mechanical ventilation, postoperative shock, sepsis, stroke and other medical problems. Additionally, surgical complications including hemorrhage / seroma / hematoma, irrigation and debridement, prosthetic joint infection, periprosthetic fracture, and wound dehiscence / nonunion were noted. Several risk factors were found to be linked with the development of POD. These included advanced age (≥ 75 years), alcohol abuse, coagulation disorders, congestive heart failure, depression, fluid and electrolyte imbalances, and more. Conversely, female sex, having private insurance, and undergoing elective hospitalization emerged as protective factors against POD.

CONCLUSION

Our findings suggest that the general prevalence of POD in rTKA is relatively low according to NIS. There was a significant connection between the POD of rTKA and advanced age, prolonged length of stay (LOS), more in-patients' costs, higher in-hospital mortality rate, increased comorbidities, postoperative medical complications and postoperative surgical complications. This study helps to understand the risk factors associated with POD to improve poor outcomes.

Association of postoperative delirium with hypotension in critically ill patients after cardiac surgery: a prospective observational study

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Summary of the Clinical Evidence for Non-Pharmacological Management of Postoperative Delirium in Adults: An Evidence Synthesis

Objective

To retrieve, evaluate, and summarise the clinical evidence for non-pharmacological interventions in adult postoperative delirium (POD), encompassing the preoperative, intraoperative, and postoperative phases.

Methods

The methods included conducting searches on UpToDate Clinical Consultants, the Scottish Intercollegiate Guidelines Network, the National Institute for Health and Care Excellence, the Registered Nurses' Association of Ontario, BMJ Best Practice, the Cochrane Library, Web of Science, PubMed, China National Knowledge Infrastructure, Wanfang, VIP, and the Chinese Biomedical Literature Service System. Clinical practice guidelines, clinical decision-making, evidence summaries, evidence synthesis, expert consensus, systematic reviews, and meta-analyses on non-pharmacological interventions for adult POD were examined, and the search period spanned between the establishment of each database and 30 October 2023.

Results

A total of 17 documents were included, comprising three guidelines, one expert consensus, one clinical decision-making article, four evidence summaries, three systematic reviews, and five meta-analyses. These documents primarily focused on the following three aspects: preoperative, intraoperative, and postoperative care. In total, 30 "best evidence" instances were compiled.

Conclusion

Considering the complexity and potential harm of adult POD, an accurate and timely evaluation of high-risk factors, alongside effective medical nursing strategies, is vital in its prevention and treatment. Non-pharmacological interventions remain the preferred choice for preventing and treating POD. Medical institutions should establish standardised processes for non-pharmacological intervention in adult POD, based on evidence-based medicine, to enhance the level of clinical care in this field.

Outcomes associated with postoperative cognitive dysfunction: a systematic review and meta-analysis

BACKGROUND

Postoperative cognitive dysfunction (POCD) manifests as a subtle decline in cognition, potentially leading to unfavourable postoperative outcomes. We explored the impact of POCD on physical function, length of hospital stay (LOS), dementia and mortality outcomes.

METHODS

PubMed and Scopus were searched until May 2023. All studies of major surgical patients that assessed POCD and outcomes of interest were included. POCD effects were stratified by surgery type (cardiac and noncardiac) and time of POCD assessment (<30 and ≥30 days postsurgery).

RESULTS

Of 2316 studies, 20 met the inclusion criteria. POCD was not associated with functional decline postsurgery. Patients who experienced POCD postcardiac surgery had an increased relative risk (RR) of death of 2.04 [(95% CI: 1.18, 3.50); I2 = 0.00%]. Sensitivity analyses showed associations with intermediate-term mortality among noncardiac surgical patients, with an RR of 1.84 [(95% CI: 1.26, 2.71); I2 = 0.00%]. Patients who developed POCD <30 days postcardiac and noncardiac surgeries experienced longer LOS than those who did not [mean difference (MD) = 1.37 days (95% CI: 0.35, 2.39); I2 = 92.38% and MD = 1.94 days (95% CI: 0.48, 3.40); I2 = 83.29%, respectively]. Postoperative delirium (POD) may contribute to the heterogeneity observed, but limited data were reported within the studies included.

CONCLUSIONS

Patients undergoing cardiac and noncardiac surgeries who developed POCD <30 days postsurgery had poorer outcomes and an increased risk of premature death. Early recognition of perioperative neurocognitive disorders in at-risk patients may enable early intervention. However, POD may confound our findings, with further studies necessary to disentangle the effects of POD from POCD on clinical outcomes.

Postoperative Cognitive Decline in Patients Undergoing Major Gynecologic Oncology Surgery: A Pilot Prospective Study

OBJECTIVES

Postoperative cognitive decline (POCD) is characterised by deficits in attention, memory, executive function, and information processing that persist beyond the early postoperative period. Its incidence ranges from 10%-25% after noncardiac surgery. Limited literature exists on POCD after gynecologic oncology surgery. Our primary objective was to identify the incidence of POCD among patients 55 years or older undergoing major gynecologic oncology surgery.

METHODS

This mixed-methods, prospective, observational cohort study followed patients 55 years or older who underwent surgery for gynecologic malignancies between February and July 2022. Semi-structured interviews and the Mini-Mental State Exam (MMSE) were administered before surgery as well as 1 and 3 months after. Assessments were delivered virtually and in-person in the context of the COVID-19 pandemic. POCD was defined as ≥2-point decline from baseline MMSE score.

RESULTS

Twenty-four patients participated; 19 completed the 1-month follow-up, and 15 completed the 3-month follow-up. The average age was 64 (range: 56-90). The mean preoperative MMSE score was 16.6 out of 17 (virtual) and 12.9 out of 13 (in-person). Two patients had a 1-point decline in their 1-month MMSE score; both recovered by 3 months. One patient had a 1-point decline in their 3-month MMSE score. Semi-structured interviews revealed common themes of "brain fog" at the 1-month follow-up and mild, persistent attention and word-finding deficits at 3 months postoperatively.

CONCLUSIONS

This study's qualitative component captured subtle subjective findings suggestive of potential POCD. Larger studies are required, and a more extensive neuropsychological test battery may be required to elicit subtle findings not clearly reflected by MMSE scores.

Intraoperative Dexmedetomidine for Prevention of Postoperative Cognitive Dysfunction and Delirium in Elderly Patients with Lobectomy: A Propensity Score-Matched, Retrospective Study

Purpose

This study aims to investigate whether dexmedetomidine could prevent postoperative cognitive dysfunction and delirium in patients with lobectomy.

Patients and Methods

Patients with lung cancer who underwent thoracoscopic lobectomy under general anesthesia were enrolled in this study and divided into dexmedetomidine group or control group. Propensity-score match (PSM) was used to reduce the bias and imbalance of confounding variables. After PSM, 87 patients in each group were included. Primary outcomes were postoperative cognitive function and delirium. Secondary outcomes include plasma TNF-α, IL-6, and S100 β protein concentrations. Adverse events were also collected.

Results

There were no significant differences in the demographic characteristics and hemodynamic parameters between the two groups. Compared with the control group, the MoCA scores were significantly higher (P<0.01), while the incidence of delirium (P<0.01) and the plasma TNF-α (P<0.01), IL-6 (P<0.01), and S100 β protein (P<0.01) concentrations were significantly lower in the dexmedetomidine group at 7 days post-operatively. The incidences of adverse events were similar between the two groups.

Conclusion

Dexmedetomidine could prevent postoperative cognitive dysfunction and delirium in patients with lobectomy by decreasing neuroinflammation.

Comparison of Propofol-Based Total Intravenous Anesthesia versus Volatile Anesthesia with Sevoflurane for Postoperative Delirium in Adult Coronary Artery Bypass Grafting Surgery: A Prospective Randomized Single-Blinded Study

OBJECTIVES

To compare the incidence of delirium and early (at 1 week) postoperative cognitive dysfunction (POCD) between propofol-based total intravenous anesthesia (TIVA) and volatile anesthesia with sevoflurane in adult patients undergoing elective coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass (CPB).

DESIGN

This was a prospective randomized single-blinded study.

SETTING

The study was conducted at a single institution, the Sree Chitra Tirunal Institute for Medical Sciences and Technology, a tertiary care institution and university-level teaching hospital.

PARTICIPANTS

Seventy-two patients undergoing elective CABG under CPB participated in this study.

INTERVENTIONS

This study was conducted on 72 adult patients (>18 years) undergoing elective CABG under CPB who were randomized to receive propofol or sevoflurane. Anesthetic depth was monitored to maintain the bispectral index between 40 and 60. Delirium was assessed using the Confusion Assessment Method for the Intensive Care Unit. Early POCD was diagnosed when there was a reduction of >2 points in the Montreal Cognitive Assessment score compared to baseline. Cerebral oximetry changes using near-infrared spectroscopy (NIRS), atheroma grades, and intraoperative variables were compared between the 2 groups.

MEASUREMENTS & MAIN RESULTS

Seventy-two patients were randomized to receive propofol (n = 36) or sevoflurane (n = 36). The mean patient age was 59.4 ± 8.6 years. The baseline and intraoperative variables, including atheroma grades, NIRS values, hemoglobin, glycemic control, and oxygenation, were comparable in the 2 groups. Fifteen patients (21.7%) patients developed delirium, and 31 patients (44.9%) had early POCD. The incidence of delirium was higher with sevoflurane (n = 12; 34.2%) compared to propofol (n = 3; 8.8%) (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.13-2.62; p = 0.027)*. POCD was higher with sevoflurane (n = 20; 57.1%) compared to propofol (n = 11; 32.3%) (OR, 1.63; 95% CI, 1.01-2.62; p = 0.038)*. In patients aged >65 years, delirium was higher with sevoflurane (7/11; 63.6%) compared to propofol (1/7; 14.2%) (p = 0.03)*.

CONCLUSIONS

Propofol-based TIVA was associated with a lower incidence of delirium and POCD compared to sevoflurane in this cohort of patients undergoing CABG under CPB. Large-scale, multicenter randomized trials with longer follow-up are needed to substantiate the clinical relevance of this observation.

Electroencephalography Monitoring for Preventing Postoperative Delirium and Postoperative Cognitive Decline in Patients Undergoing Cardiothoracic Surgery: A Meta-Analysis

Background

Patients undergoing cardiothoracic surgery frequently encounter perioperative neurocognitive disorders (PND), which can include postoperative delirium (POD) and postoperative cognitive decline (POCD). Currently, there is not enough evidence to support the use of electroencephalograms (EEGs) in preventing POD and POCD among cardiothoracic surgery patients. This meta-analysis examined the importance of EEG monitoring in POD and POCD.

Methods

Cochrane Library, PubMed, and EMBASE databases were searched to obtain the relevant literature. This analysis identified trials based on the inclusion and exclusion criteria. The Cochrane tool was used to evaluate the methodological quality of the included studies. Review Manager software (version 5.3) was applied to analyze the data.

Results

Four randomized controlled trials (RCTs) were included in this meta-analysis, with 1096 participants. Our results found no correlation between EEG monitoring and lower POD risk (relative risk (RR): 0.81; 95% CI: 0.55-1.18; p = 0.270). There was also no statistically significant difference between the EEG group and the control group in the red cell transfusions (RR: 0.86; 95% CI: 0.51-1.46; p = 0.590), intensive care unit (ICU) stay (mean deviation (MD): -0.46; 95% CI: -1.53-0.62; p = 0.410), hospital stay (MD: -0.27; 95% CI: -2.00-1.47; p = 0.760), and mortality (RR: 0.33; 95% CI: 0.03-3.59; p = 0.360). Only one trial reported an incidence of POCD, meaning we did not conduct data analysis on POCD risk.

Conclusions

This meta-analysis did not find evidence supporting EEG monitoring as a potential method to reduce POD incidence in cardiothoracic surgery patients. In the future, more high-quality RCTs with larger sample sizes are needed to validate the relationship between EEG monitoring and POD/POCD further.

Remote ischemic preconditioning and cognitive dysfunction following coronary artery bypass grafting: A systematic review and meta-analysis of randomized controlled trials

Introduction

Postoperative cognitive dysfunction (POCD) is a common neurological issue following cardiopulmonary bypass (CPB)-assisted heart surgery. Remote ischemic preconditioning (RIPC) increases the tolerance of vital organs to ischemia/reperfusion injury, leading to reduced brain injury biomarkers and improved cognitive control. However, the exact mechanisms underlying RIPC's neuroprotective effects remain unclear. This systematic review aimed to explore the hypothesis that RIPC lowers neurocognitive dysfunction in patients undergoing CPB surgery.

Method

All relevant studies were searched in PubMed, ScienceDirect, EBSCOhost, Google Scholar, Semantic Scholar, Scopus, and Cochrane Library database. Assessment of study quality was carried out by two independent reviewers individually using the Cochrane Risk of Bias (RoB-2) tool. Meta-analysis was performed using a fixed-effect model due to low heterogeneity among studies, except for those with substantial heterogeneity.

Results

A total of five studies with 1,843 participants were included in the meta-analysis. RIPC was not associated with reduced incidence of postoperative cognitive dysfunction (five RCTs, odds ratio [OR:] 0.79, 95% confidence interval [CI]: 0.56-1.11) nor its improvement (three RCTs, OR: 0.80, 95% CI: 0.50-1.27). In addition, the analysis of the effect of RIPC on specific cognitive function tests found that pooled SMD for RAVLT 1-3 and RAVLT LT were -0.07 (95% CI: -0.25,012) and -0.04 (95% CI: -0.25-0.12), respectively, and for VFT semantic and phonetic were -0.15 (95% CI: -0.33-0.04) and 0.11 (95% CI: -0.40-0.62), respectively.

Conclusion

The effect of RIPC on cognitive performance in CABG patients remained insignificant. Results from previous studies were unable to justify the use of RIPC as a neuroprotective agent in CABG patients.

Risk Factors for Postoperative Cognitive Decline After Orthopedic Surgery in Elderly Chinese Patients: A Retrospective Cohort Study

Purpose

We aimed to identify the risk factors for postoperative cognitive decline (POCD) by evaluating the outcomes from preoperative comprehensive geriatric assessment (CGA) and intraoperative anesthetic interventions.

Patients and Methods

Data used in the study were obtained from the Aged Patient Perioperative Longitudinal Evaluation-Multidisciplinary Trial (APPLE-MDT) cohort recruited from the Department of Orthopedics in Xuanwu Hospital, Capital Medical University between March, 2019 and June, 2022. All patients accepted preoperative CGA by the multidisciplinary team using 13 common scales across 15 domains reflecting the multi-organ functions. The variables included demographic data, scales in CGA, comorbidities, laboratory tests and intraoperative anesthetic data. Cognitive function was assessed by Montreal Cognitive Assessment scale within 48 hours after admission and after surgery. Dropping of ≥1 point between the preoperative and postoperative scale was defined as POCD.

Results

We enrolled 119 patients. The median age was 80.00 years [IQR, 77.00, 82.00] and 68 patients (57.1%) were female. Forty-two patients (35.3%) developed POCD. Three cognitive domains including calculation (P = 0.046), recall (P = 0.047) and attention (P = 0.007) were significantly worsened after surgery. Univariate analysis showed that disability of instrumental activity of daily living, incidence rate of postoperative respiratory failure (PRF) ≥4.2%, STOP-Bang scale score, Caprini risk scale score and Sufentanil for maintenance of anesthesia were different between the POCD and non-POCD patients. In the multivariable logistic regression analysis, PRF ≥ 4.2% (odds ratio [OR] = 2.343; 95% confidence interval [CI]: 1.028-5.551; P = 0.046) and Sufentanil for maintenance of anesthesia (OR = 0.260; 95% CI: 0.057-0.859; P = 0.044) was independently associated with POCD as risk and protective factors, respectively.

Conclusion

Our study suggests that POCD is frequent among older patients undergoing elective orthopedic surgery, in which decline of calculation, recall and attention was predominant. Preoperative comprehensive geriatric assessments are important to identify the high-risk individuals of POCD.

Early postoperative neurocognitive complications in elderly patients: comparing those with and without preexisting mild cognitive impairment- a prospective study

BACKGROUND

As societies age, increasing numbers of older adults undergo surgeries with anesthesia. Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) frequently occur in older surgical patients. Most of these patients already have preoperative mild cognitive impairment (MCI). However, the correlation between MCI and POD remains unclear. This study aimed to determine the incidence of POD in elderly patients with and without preexisting MCI.

METHODS

A prospective study enrolled patients aged 60 years and above scheduled for major surgeries between December 2017 and April 2022. Preoperative MCI was determined by a Montreal Cognitive Assessment (MoCA) score between 18 and 24. POD was diagnosed using criteria from the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). POCD was characterized by a MoCA score reduction of 2 or more points from the preoperative score. The primary outcome was the incidence of POD within the first 72 h postoperatively. Secondary outcomes encompassed other postoperative complications, including POCD.

RESULTS

The study comprised 223 elderly patients with MCI and 56 without MCI. The incidence of POD was 16.6% in the MCI group and 14.3% in the non-MCI group (P = 0.839). POCD occurred in 24.3% of MCI patients and 50% of non-MCI patients (P = 0.001). There were no significant differences in other postoperative complications between the groups. Postoperatively, the MCI group notably declined in visuospatial, attention, and orientation domains, while the non-MCI group declined in all domains except delayed recall.

CONCLUSIONS

The incidence of POD was similar in the MCI and non-MCI groups. However, the non-MCI group demonstrated a higher incidence of POCD than the MCI group. This was identified by a reduction in postoperative MoCA scores for the visuospatial, naming, attention, language, abstraction, and orientation domains. These findings underscore the importance of postoperative cognitive assessments for both elderly patients with preexisting MCI and those with previously intact cognitive functions.

TRIAL REGISTRATION

This trial was retrospectively registered in the Thai Clinical Trials Registry on 15/01/2019 (registration number: TCTR20190115001).

Thoracic delirium index for predicting postoperative delirium in elderly patients following thoracic surgery: A retrospective case-control study

BACKGROUND

Postoperative delirium (POD) is an acute neurological complication in the elderly undergoing thoracic surgery and can result in serious adverse consequences.

AIMS

This study aimed to identify the related risk factors for POD following thoracic surgery, primarily focusing on preoperative serum biomarkers, and further to establish a novel delirium index to better predict POD.

METHODS

A total of 279 patients aged ≥60 years who underwent elective thoracic surgery from August 2021 to August 2022 were enrolled in this observational study. The platelet-to-white blood cell ratio (PWR) was calculated as number the of platelets divided by the number of white blood cells. POD was defined by the confusion assessment method twice daily during the postoperative first 3 days. Multivariate regression analysis was performed to identify all potential variables for POD. Moreover, a novel thoracic delirium index (TDI) was developed based on the related risk factors. The accuracy of TDI and its component factors in predicting POD was determined by the curve of receiver operating characteristic (ROC).

RESULTS

In total, 25 of 279 patients developed POD (8.96%). Age, PWR, and average pain scores within the first 3 days after surgery were regarded as the independent risk factors for POD. Moreover, the ROC analysis showed the TDI, including age, PWR, and average pain scores within the first 3 days after surgery, can more accurately predict POD with the largest area under the curve of 0.790 and the optimal cutoff value of 9.072, respectively.

CONCLUSION

The TDI can scientifically and effectively predict POD to provide optimal clinical guidance for older patients after thoracic surgery.

Relationship between preoperative neutrophil-to-lymphocyte ratio and postoperative delirium: The PNDABLE and the PNDRFAP cohort studies

OBJECTIVES

In this study, the relationship between preoperative neutrophil-to-lymphocyte ratio (NLR) and Alzheimer-related biomarkers in cerebrospinal fluid (CSF) was investigated to determine whether high NLR is a potential risk factor for postoperative delirium (POD) and to evaluate its predictive efficacy.

METHODS

We selected 1000 patients from the perioperative neurocognitive disorder risk factor and prognosis (PNDRFAP) database and 999 patients from the perioperative neurocognitive disorder and biomarker lifestyle (PNDABLE) database. Patients in the PNDABLE database have been measured for Alzheimer-related biomarkers in CSF (Aβ40 , Aβ42 , P-tau, and tau protein). Mini-mental state examination was used to assess the preoperative mental status of patients. POD was diagnosed using the confusion assessment method and assessed for severity using the memorial delirium assessment scale. Logistic regression analysis was utilized to explore the association of preoperative NLR with POD. What's more, we also performed sensitivity analysis by adding corrected confounders, and the results were almost unchanged. Spearman's rank correlation was used to determine the associations between NLR and Alzheimer-related biomarkers. Mediation analyses with 10,000 bootstrapped iterations were used to explore the mediation effects. Finally, we use decision curves and the nomogram model to evaluate the efficacy of preoperative NLR in predicting POD; we also performed external validation using data from Qilu Hospital.

RESULT

Logistic regression results showed that an elevated preoperative NLR was a risk factor for the development of POD in patients (PNDRFAP: OR = 1.067, 95% CI 1.020-1.116; PNDABLE: OR = 1.182, 95% CI 1.048-1.335, p < .05). Spearman's rank correlation analysis showed a positive but weak correlation between NLR and P-tau/T-tau (R = .065). The mediating effect results indicate that NLR likely mediates the occurrence of POD through elevated tau protein levels (proportion: 47.47%). The results of the box plots showed statistically significant NLR and CSF biomarkers between the POD and non-POD (NPOD) groups (p < .05), with higher NLR, P-tau, and T-tau in the POD group than in the NPOD group. In contrast, the NPOD group had higher Aβ42 levels compared to the POD group. In addition, we used R package to plot the decision curve and nomogram both suggesting a good predictive effect of preoperative NLR on the occurrence of POD.

CONCLUSION

Elevated preoperative NLR levels may be a risk factor for POD and likely mediate the development of POD through elevated P-tau/T-tau levels.

Dynamic Nomogram for Subsyndromal Delirium in Adult Intensive Care Unit: A Prospective Cohort Study

Purpose

To develop a dynamic nomogram of subsyndromal delirium (SSD) in intensive care unit (ICU) patients and internally validate its efficacy in predicting SSD.

Patients and Methods

Patients who met the inclusion and exclusion criteria in the ICU of a tertiary hospital in Zhejiang from September 2021 to June 2022 were selected as the research objects. The patient data were randomly divided into the training set and validation set according to the ratio of 7:3. The least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression were used to screen the predictors of SSD, and R software was used to construct a dynamic nomogram. Receiver operating characteristic (ROC) curve, calibration band and decision curve were used to evaluate the discrimination, calibration and clinical effectiveness of the model.

Results

A total of 1000 eligible patients were included, including 700 in the training set and 300 in the validation set. Age, drinking history, C reactive protein level, APACHE II, indwelling urinary catheter, mechanical ventilation, cerebrovascular disease, respiratory failure, constraint, dexmedetomidine, and propofol were predictors of SSD in ICU patients. The ROC curve values of the training set was 0.902 (95% confidence interval: 0.879-0.925), the best cutoff value was 0.264, the specificity was 78.4%, and the sensitivity was 88.0%. The ROC curve values of the validation set was 0.888 (95% confidence interval: 0.850-0.930), the best cutoff value was 0.543, the specificity was 94.9%, and the sensitivity was 70.9%. The calibration band showed good calibration in the training and validation set. Decision curve analysis showed that the net benefit in the model was significantly high.

Conclusion

The dynamic nomogram has good predictive performance, so it is a precise and effective tool for medical staff to predict and manage SSD in the early stage.

The Potential Value of Systemic Inflammation Response Index on Delirium After Hip Arthroplasty Surgery in Older Patients: A Retrospective Study

Purpose

To explore the relationship between the systemic inflammation response index (SIRI) and postoperative delirium (POD) in older patients with hip arthroplasty surgery.

Patients and Methods

Older patients who underwent elective hip arthroplasty surgery were included in this retrospective study. SIRI, neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were collected from blood routine examination at admission. Binary logistic regression analysis was performed to evaluate the association between SIRI levels and POD was analyzed.

Results

Ultimately, 116 older patients who met the inclusion criteria were assessed. Thirty-four (29%) of 116 patients diagnosed with POD were defined as the POD group, and the rest consisted of the Non-POD group. Compared with non-POD patients, POD patients showed significantly higher levels of SIRI (P < 0.001) and NLR (P = 0.002) at admission. There was no significance in the levels of PLR between two groups. SIRI was independently associated with the occurrence of POD in multivariate logistic regression analysis [odds ratio (OR) = 3.34, 95% confidence interval (95% CI) = 1.26-8.85, P = 0.016]. Receiver operating characteristic curve analysis indicated that SIRI with an optimal cutoff value of 0.987 predicted the POD with a sensitivity of 88.2% and specificity of 74.4%, and the area under the curve was 0.82 (95% CI, 0.74-0.90, P < 0.01).

Conclusion

Preoperative SIRI and NLR levels in the blood are associated with the occurrence of POD. Moreover, preoperative SIRI level is a useful candidate biomarker to identify delirium after elective hip arthroplasty surgery in older patients.

Incidence and Factors Related to Prolonged Postoperative Cognitive Decline (POCD) in Elderly Patients Following Surgery and Anaesthesia: A Systematic Review

Aim

The aim of this systematic review is to explore the current literature to provide evidence regarding the incidence and risk factors of prolonged POCD in elderly patients following cardiac and non-cardiac surgical interventions.

Methods

The PubMed and Google Scholar databases were searched using appropriate keywords and search engines for adequate evidence from studies meeting the inclusion criteria so as to reveal the end-point, which was the presence of prolonged POCD in elderly patients following surgery and anaesthesia. The incidence of POCD at different time intervals and the variables predicting the occurrence of POCD were analysed.

Results

The results of 23 articles covering 5077 patients (3694 non cardiac and 1383 cardiac surgeries) were carefully analysed. POCD occurs from the first postoperative day and lasts for potentially long periods. The incidence of POCD in this review ranged from 2.2% to 35.7%. More specifically, it ranged from 2.2% to 31.5% in non-cardiac surgeries and 11.8% to 35.7% in patients who had undergone cardiac surgeries. Some of the independent risk factors (predictors) for the development of POCD were advanced age, high concentration of neuroinflammatory mediators detectable in plasma, low SpO2, longer anaesthetic and surgical duration, and depth of anaesthesia.

Conclusion

This review can only provide limited evidence of prolonged POCD (more than a year) and further research that involves better study designs, larger samples, involving longer follow-up, and at different sites (multicentre) is highly advised. This in turn may help researchers and clinicians to discover the actual causes and risk factors and develop appropriate preventive and treatment protocols to tackle POCD in the ageing surgical population.

The effect of relative cerebral hyperperfusion during cardiac surgery with cardiopulmonary bypass to delayed neurocognitive recovery

OBJECTIVE

Delayed neurocognitive recovery (dNCR) remains a common complication after surgery and the incidence of it is determined 30-80% after cardiac surgery with cardiac bypass (CPB) in eldery patients. Many researchers have identified that neuropsychological complications emerge from insufficient cerebral perfusion. Relative cerebral hyperperfusion also disrupts cerebral autoregulation and might play a significant role in dNCR development. The aim of this study is to determine hyperperfusion in the middle cerebral artery during CPB influence to dNCR development and brain biomarker glial fibrillary acidic protein (GFAP) impact in diagnosing dNCR.

DESIGNS AND METHODS

This prospective - case control study included patients undergoing elective coronary artery bypass grafting or/and valve surgery with CPB. For cognitive evaluation 101 patients completed Addenbrooke's cognitive examination - ACE-III. To determine mild cognitive dysfunction, cut - off 88 was chosen. Mean BFV was monitored with transcranial Doppler ultrasonography (TCD) and performed before surgery, after induction of anaesthesia, during CPB and after surgery. Preoperative BFV was converted to 100% and used as a baseline. The percentage change of cerebral blood flow velocity during CPB was calculated from baseline. Patients with decreased blood flow velocity were included for further investigation. To measure glial fibrillary acidic protein, blood samples were collected after anaesthesia induction, 24 and 48 h after the surgery. According to the ACE-III test results, patients with relative hyperperfusion were divided into two groups: with Delayed neurocognitive recovery and without dNCR (non-dNCR group).

RESULTS

101 patients were examined, 67 (69.1%) men and 29 (29.9%) women, age 67.9 (SD 9.2) Increased percentage of BFV was determined for 40 (39.60%) patients. There were no differences in sex, haematocrit, paCO2, aortic cross-clamping or CPB time between the two groups. Percentage change of BFV was 105.60% in the non-dNCR group and 132.29% in the dNCR group, p = .033. Patients who developed dNCR in the early post-surgical period were significantly older, p < .001 and had a lower baseline of BFV, p = .004. GFAP concentration significantly increased in the dNCR group 48 hours after surgery, compared to the non-dNCR group, p = .01.

CONCLUSIONS

Relative hyperperfusion during CPB may cause dNCR. Elderly patients are sensitive to blood flow velocity acceleration during CPB. GFAP concentration increased 48 h after surgery in dNCR group but did not have any connection with risk factors.

New advances in clinical application of neostigmine: no longer focusing solely on increasing skeletal muscle strength

Neostigmine is a clinical cholinesterase inhibitor, that is, commonly used to enhance the function of the cholinergic neuromuscular junction. Recent studies have shown that neostigmine regulates the immune-inflammatory response through the cholinergic anti-inflammatory pathway, affecting perioperative neurocognitive function. This article reviews the relevant research evidence over the past 20 years, intending to provide new perspectives and strategies for the clinical application of neostigmine.

Development and Validation of a Delirium Risk Prediction Model for Elderly Patients Undergoing Elective Orthopedic Surgery

Purpose

This study aimed to develop and validate a post-operative delirium (POD) nomogram in a population of elderly patients undergoing elective orthopedic surgery.

Patients and Methods

A predictive model was developed based on a training dataset of 474 elderly patients undergoing elective orthopedic surgery from March 2021 to May 2022. POD was identified using the Confusion Assessment Methods (CAM). The least absolute shrinkage and selection operator (LASSO) method was used to screen risk factors, and prediction models were created by combining the outcomes with logistic regression analysis. We employ bootstrap validation for internal validation to examine the model's repeatability. The results were validated using a prospective study on 153 patients operated on from January 2022 to May 2022 at another institution.

Results

The predictors in the POD nomogram included age, the Mini-Mental State Examination(MMSE), sleep disorder, neurological disorders, preoperative serum creatinine (Pre-SCR), and ASA classification. The c-index of the model was 0.928 (95% confidence interval 0.898 ~ 0.957) and the bootstrap validation still achieved a high c-index of 0.912. The c-index of the external validation was 0.921. The calibration curve for the diagnostic probability showed good agreement between prediction by nomogram and actual observation.

Conclusion

By combining preoperative and intraoperative clinical risk factors, we created a POD risk nomogram to predict the probability of POD in elderly patients who undergo elective orthopedic surgery. It could be a tool for guiding individualized interventions.

Effectiveness of cognitive interventions for adult surgical patients after general anaesthesia to improve cognitive functioning: A systematic review

AIMS AND OBJECTIVES

To examine the effectiveness of cognitive interventions after general anaesthesia to improve cognitive functioning.

BACKGROUND

The number of surgical procedures performed worldwide is large and growing. Postoperative cognitive dysfunction is a common complication associated with poor postoperative outcomes. A variety of cognitive interventions have been developed to maintain or improve cognitive function in one or more cognitive domains. Cognitive interventions have shown to be effective in healthy older populations, those with mild cognitive impairment, and those with heart failure. The impact of cognitive interventions in surgical patients after general anaesthesia is a relatively new focus of research and is therefore less well established.

METHODS

Seven bibliographic databases were searched in relation to 'surgery' and 'cognitive interventions'; no date or language limits were imposed. Studies including adult patients who were scheduled for, or who had undergone surgery under general anaesthesia, had a baseline cognitive assessment using a validated measurement, and had engaged with any cognition-based intervention were included. Full-text review for inclusion, quality assessment and data extraction were undertaken independently by two authors. This study is reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.

RESULTS

A total of 550 papers were identified for possible inclusion, of which nine met the inclusion criteria and were included in the review. The majority were randomised controlled trials (RCTs) (n = 6 [66.7%]). Four studies used computerised cognitive interventions, while five used traditional cognitive interventions. Most of the studies used multi-domain cognitive training focusing on two or more domains (n = 7 [77.8%]) while two studies used single-domain cognitive training. Memory (n = 7 [77.8%]) and attention (n = 5 [55.6%]) were the cognitive domains most often targeted during the intervention.

CONCLUSIONS

The use of cognitive interventions demonstrated some efficacy in improving cognitive function after general anaesthesia, particularly those targeting memory.

RELEVANCE FOR CLINICAL PRACTICE

The findings of this review suggest that cognitive interventions show promise at improving cognitive performance in patients with POCD and could be usefully implemented in clinical practice to improve patient outcomes.

Effect of Ketamine on Postoperative Neurocognitive Disorders: A Systematic Review and Meta-Analysis

BACKGROUND

Neurocognitive alterations in the perioperative period might be caused by a wide variety of factors including pain, blood loss, hypotension, hypoxia, micro- and macroemboli, cardiopulmonary bypass (CPB), reperfusion damage, and surgery itself, and all are risk factors for developing postoperative delirium (POD) and postoperative cognitive dysfunction (POCD). The objective of this study was to evaluate the effect of ketamine on neurocognitive dysfunction after anesthesia.

METHODS

We conducted a meta-analysis of randomized controlled trials (RCTs) comparing ketamine use (experimental group) with placebo (controls).

RESULTS

The model favors the control group over the experimental group in terms of frequency of hallucinations (the risk ratio with 95% CI is 1.54 [1.09, 2.19], p-value = 0.02), the number of patients readmitted within 30 days (RR with 95% CI is 0.25 [0.09, 0.70]), and the number of adverse events (overall RR with 95% CI is 1.31 [1.06, 1.62]). In terms of morphine consumption, the model favors the experimental group.

CONCLUSION

There was no statistically significant difference in incidences of postoperative delirium, vasopressor requirement, and fentanyl consumption between the ketamine and control groups. However, hallucinations were more frequently reported in the ketamine group.

Alcohol consumption may be associated with postoperative delirium in the elderly: the PNDABLE study

OBJECTIVES

This study aimed to reveal the relationship between alcohol consumption and Postoperative delirium (POD) in the elderly.

METHODS

We selected 252 patients from the Perioperative Neurocognitive Disorder And Biomarker Lifestyle (PNDABLE ) study. Patients in the PNDABLE database have been measured for Alzheimer-related biomarkers in CSF (Aβ40, Aβ42, P-tau, and tau protein). Mini-Mental State Examination (MMSE) was used to assess the preoperative mental status of patients. POD was diagnosed using the Confusion Assessment Method (CAM) and assessed for severity using the Memorial Delirium Assessment Scale (MDAS). Logistic regression analysis was utilized to explore the association of alcohol consumption with POD. Linear regression analysis was used to study the relationship between alcohol consumption and CSF biomarkers. Mediation analyses with 10,000 bootstrapped iterations were used to explore the mediation effects. Finally, we constructed the receiver operating characteristic (ROC) curve and the nomogram model to evaluate the efficacy of alcohol consumption and CSF biomarkers in predicting POD.  RESULT: The incidence of POD was 17.5%. Logistic regression showed that alcohol consumption (OR = 1.016, 95%CI 1.009-1.024, P < 0.001) is a risk factor for POD. What's more, Aβ42 is a protective factor for POD (OR = 0.993, 95%CI 0.989-0.997, P < 0.05), and P-Tau was a risk factor for POD (OR = 1.093, 95%CI 1.022-1.168, P < 0.05). Linear regression analysis revealed that alcohol consumption was negatively associated with CSF Aβ42 (β = -0.638, P < 0.001) in POD patients. Mediation analyses showed that alcohol consumption is likely to partially mediate POD through Aβ42 (proportion:14.21%). ROC curve showed that alcohol consumption (AUC = 0.904; P < 0.001) exhibited a relatively better discriminatory ability in POD prediction compared to Aβ42 (AUC = 0.798; P < 0.001). The calibration curve indicated a good nomogram prediction (P = 0.797).

CONCLUSION

Alcohol consumption is a risk factor for POD (particularly for those with > 24 g a day on average) in the elderly, and contributes to POD through the mediation of Aβ42.

Frequency and Risk Factors of Subsyndromal Delirium in the Intensive Care Units: A Prospective Cohort Study

Background

Subsyndromal delirium (SSD) is a common neuropsychiatric disorder among the intensive care units (ICU) patients. SSD is characterized by the presence of delirium symptoms but it does not meet the diagnostic criteria of delirium, resulting in poor patient prognosis.

Objective

The aim of this study was to explore the prevalence and risk factors for SSD among adult patients admitted to the ICU of XXX hospital in Southwest China.

Methods

The study participants comprised 309 patients referred to the ICU in XXX hospital between 10th August 2021 and 5th June 2022. Demographic information, medical history, and other patient information were recorded. ICDSC assessment, physical examination and laboratory tests were performed on enrolled patients. Cognitive evaluation was conducted using the MMSE method.

Results

The results showed that out the 309 patients, 99 had possible SSD (prevalence of 32.0%), with 55 SSD1 cases (ICDSC score of 1, 17.8% prevalence), 29 SSD2 cases (ICDSC score of 2, 9.4% prevalence) and 15 SSD3 cases (ICDSC score of 3, 4.9% prevalence). Previous history of mental illness (OR, 3.741; 95% CI, 1.136-12.324; P <0.05), auxiliary ventilation (OR, 3.364; 95% CI, 1.448-7.813; P <0.01), hemodialysis (OR, 11.369; 95% CI, 1.245-103.840; P <0.05), MMSE score (OR, 0.845; 95% CI, 0.789-0.904; P <0.001) and a temperature ≥ 37.5 °C (OR, 3.686; 95% CI, 1.404-9.732; P <0.01) were independent risk factors for occurrence of SSD among ICU patients.

Conclusion

Approximately one-third of the patients in the intensive care unit had high risk of SSD. Nursing staff should pay attention to management of the high-risk patients to prevent SSD from progressing delirium to improve patient prognosis.

Associations Between Systemic and Cerebral Inflammation in an Ovine Model of Cardiopulmonary Bypass

BACKGROUND

Intraoperative inflammation may contribute to postoperative neurocognitive disorders after cardiac surgery requiring cardiopulmonary bypass (CPB). However, the relative contributions of general anesthesia (GA), surgical site injury, and CPB are unclear.

METHODS

In adult female sheep, we investigated (1) the temporal profile of proinflammatory and anti-inflammatory cytokines and (2) the extent of microglia activation across major cerebral cortical regions during GA and surgical trauma with and without CPB (N = 5/group). Sheep were studied while conscious, during GA and surgical trauma, with and without CPB.

RESULTS

Plasma tumor necrosis factor-alpha (mean [95% confidence intervals], 3.7 [2.5-4.9] vs 1.6 [0.8-2.3] ng/mL; P = .0004) and interleukin-6 levels (4.4 [3.0-5.8] vs 1.6 [0.8-2.3] ng/mL; P = .029) were significantly higher at 1.5 hours, with a further increase in interleukin-6 at 3 hours (7.0 [3.7-10.3] vs 1.8 [1.1-2.6] ng/mL; P < .0001) in animals undergoing CPB compared with those that did not. Although cerebral oxygen saturation was preserved throughout CPB, there was pronounced neuroinflammation as characterized by greater microglia circularity within the frontal cortex of sheep that underwent CPB compared with those that did not (0.34 [0.32-0.37] vs 0.30 [0.29-0.32]; P = .029). Moreover, microglia had fewer branches within the parietal (7.7 [6.5-8.9] vs 10.9 [9.4-12.5]; P = .001) and temporal (7.8 [7.2-8.3] vs 9.9 [8.2-11.7]; P = .020) cortices in sheep that underwent CPB compared with those that did not.

CONCLUSIONS

CPB enhanced the release of proinflammatory cytokines beyond that initiated by GA and surgical trauma. This systemic inflammation was associated with microglial activation across 3 major cerebral cortical regions, with a phagocytic microglia phenotype within the frontal cortex, and an inflammatory microglia phenotype within the parietal and temporal cortices. These data provide direct histopathological evidence of CPB-induced neuroinflammation in a large animal model and provide further mechanistic data on how CPB-induced cerebral inflammation might drive postoperative neurocognitive disorders in humans.

Hematic Antegrade Repriming Reduces Emboli on Cardiopulmonary Bypass: A Randomized Controlled Trial

Particulate and gaseous microemboli (GME) are side effects of cardiac surgery that interfere with postoperative recovery by causing endothelial dysfunction and vascular blockages. GME sources during surgery are multiple, and cardiopulmonary bypass (CPB) is contributory to this embolic load. Hematic antegrade repriming (HAR) is a novel procedure that combines the benefits of repriming techniques with additional measures, by following a standardized procedure to provide a reproducible hemodilution of 300 ml. To clarify the safety of HAR in terms of embolic load delivery, a prospective and controlled study was conducted, by applying Doppler probes to the extracorporeal circuit, to determine the number and volume of GME released during CPB. A sample of 115 patients (n = 115) was considered for assessment. Both groups were managed under strict normothermia, and similar clinical conditions and protocols, receiving the same open and minimized circuit. Significant differences in GME volume delivery (control group [CG] = 0.28 ml vs. HAR = 0.08 ml; p = 0.004) and high embolic volume exposure (>1 ml) were found between the groups (CG = 30.36% vs. HAR = 4.26%; p = 0.001). The application of HAR did not represent an additional embolic risk and provided a four-fold reduction in the embolic volume delivered to the patient (coefficient, 0.24; 95% CI, 0.08-0.72; p = 0.01), which appears to enhance GME clearance of the oxygenator before CPB initiation.

Transcutaneous Electrical Acupoint Stimulation for Preventing Postoperative Delirium: A Meta-Analysis

Objective

This meta-analysis of randomized controlled trials (RCTs) aims to evaluate the efficacy and safety of transcutaneous electrical acupoint stimulation (TEAS) for postoperative delirium (POD) in surgical patients.

Methods

Based on database searches of the Wanfang, China National Knowledge Infrastructure (CNKI), VIP, Chinese Biology Medicine (CBM), PubMed, Cochrane Library, and Web of Science, relevant RCTs published before December 30, 2022, were extracted. Outcome indicators included the incidence of POD, changes in Confusion Assessment Method (CAM) scores, Visual Analogue Scale (VAS) scores, and the intraoperative consumption of anesthetics. Data were pooled and analyzed by Review Manager 5.3, and publication bias detection was conducted using Stata 17.0.

Results

A meta-analysis containing 715 experimental and 717 control participants from 12 RCTs was performed. The overall results showed that TEAS had obvious superiority with a lower incidence of POD on any day during the postoperative 1 week. In subgroup analyses, the CAM scores on the third postoperative day were significantly lower in the TEAS group than in the control group (MD = -0.52, 95% CI: -1.02 to -0.03, P = 0.04), the VAS scores on the first postoperative day were significantly lower in the TEAS group than in the control group (MD = -0.19, 95% CI: -0.36 to -0.02, P = 0.03), the consumption of propofol and remifentanil were both significantly lower in the TEAS group compared with the control group (MD = -23.1, 95% CI: -37.27 to -8.94, P = 0.001; MD = -105.69, 95% CI: -174.20 to -37.19, P = 0.002). No serious adverse events of TEAS were reported in any of the referenced studies.

Conclusion

TEAS has an obvious curative effect in preventing POD and pain in the earlier stage of surgical patients. It could be a promising assisted anesthesia technique in the future.

Targeting neuroinflammation as a preventive and therapeutic approach for perioperative neurocognitive disorders

Perioperative neurocognitive disorders (PND) is a common postoperative complication associated with regional or general anesthesia and surgery. Growing evidence in both patient and animal models of PND suggested that neuroinflammation plays a critical role in the development and progression of this problem, therefore, mounting efforts have been made to develop novel therapeutic approaches for PND by targeting specific factors or steps alongside the neuroinflammation. Multiple studies have shown that perioperative anti-neuroinflammatory strategies via administering pharmacologic agents or performing nonpharmacologic approaches exert benefits in the prevention and management of PND, although more clinical evidence is urgently needed to testify or confirm these results. Furthermore, long-term effects and outcomes with respect to cognitive functions and side effects are needed to be observed. In this review, we discuss recent preclinical and clinical studies published within a decade as potential preventive and therapeutic approaches targeting neuroinflammation for PND.

Emotion recognition dysfunction after anesthesia and cardiac surgery

Cognitive dysfunction after anesthesia and surgery has long been recognized. Recently, researchers provided empirical evidence for social cognition dysfunction (SCD) after anesthesia and surgery. In the present study, we concentrated on the deficits in emotion recognition, one of the most important clinical perspectives in SCD, in patients who underwent cardiac surgery. Biological motion (BM) was considered as the stimulus of interest, and patients' abilities of BM emotion perception and action perception before and after anesthesia and surgery were examined. In total, 60 adult patients (40-72 years old) completed the BM recognition task, which required them to label the types of actions and emotions of perceived BM. The results showed that while action perception remained intact after cardiac surgery, 18.3% of patients exhibited deficits in emotion perception, further confirming the existence of SCD after anesthesia and surgery.

Monitoring of Post-Brain Injuries By Measuring Plasma Levels of Neuron-Derived Extracellular Vesicles

BACKGROUND

Extracellular vesicles (EV) released from neurons into the blood can reflect the state of nervous tissue. Measurement of neuron derived EV (NDE) may serve as an indicator of brain injury.

METHODS

A sandwich immunoassay was established to measure plasma NDE using anti-neuron CD171 and anti-EV CD9 ([CD171 ⁺ CD9⁺]). Plasma samples were obtained from commercial sources, cross-country (n = 9), football (n = 22), soccer (n = 19), and rugby (n = 18) athletes over time. Plasma was also collected from patients undergoing total aortic arch replacement (TAR) with selective cerebral perfusion during cardiopulmonary bypass before and after surgery (n = 36).

RESULTS

The specificity, linearity, and reproducibility of NDE assay (measurement of [CD171 ⁺ CD9⁺]) were confirmed. By scanning electron microscopy and nanoparticle tracking, spherical vesicles ranging in size from 150 to 300 nm were confirmed. Plasma levels of NDE were widely spread over 2 to 3 logs in different individuals with a significant age-dependent decrease. However, NDE were very stable in each individual within a ± 50% change over time (cross-country, football, soccer), whereas rugby players were more variable over 4 years. In patients undergoing TAR, NDE increased rapidly in days post-surgery and were significantly (P = .0004) higher in those developing postoperative delirium (POD) (n = 13) than non-delirium patients (n = 23).

CONCLUSIONS

The blood test to determine plasma levels of NDE was established by a sandwich immunoassay using 2 antibodies against neuron (CD171) and exosomes (CD9). NDE levels varied widely in different individuals and decreased with age, indicating that NDE levels should be considered as a normalizer of NDE biomarker studies. However, NDE levels were stable over time in each individual, and increased rapidly after TAR with greater increases associated with patients developing POD. This assay may serve as a surrogate for evaluating and monitoring brain injuries.

Volatile Anaesthesia versus Total Intravenous Anaesthesia for Cardiac Surgery—A Narrative Review

Recent research has contested the previously accepted paradigm that volatile anaesthetics improve outcomes in cardiac surgery patients when compared to intravenous anaesthesia. In this review we summarise the mechanisms of myocardial ischaemia/reperfusion injury and cardioprotection in cardiac surgery. In addition, we make a comprehensive analysis of evidence comparing outcomes in patients undergoing cardiac surgery under volatile or intravenous anaesthesia, in terms of mortality and morbidity (cardiac, neurological, renal, pulmonary).

Persistent Depletion of Neuroprotective Factors Accompanies Neuroinflammatory, Neurodegenerative, and Vascular Remodeling Spectra in Serum Three Months after Non-Emergent Cardiac Surgery

We hypothesized that the persistent depletion of neuroprotective markers accompanies neuroinflammation and neurodegeneration in patients after cardiac surgery. A total of 158 patients underwent elective heart surgery with their blood collected before surgery (t_baseline) and 24 h (t_24hr), seven days (t_7d), and three months (t_3m) post-surgery. The patients’ serum was measured for markers of neurodegeneration (τau, τaup181–183, amyloid β1-40/β2-42, and S100), atypical neurodegeneration (KLK6 and NRGN), neuro-injury (neurofilament light/heavy, UC-HL, and GFAP), neuroinflammation (YKL-40 and TDP-43), peripheral nerve damage (NCAM-1), neuroprotection (apoE4, BDNF, fetuin, and clusterin), and vascular smoldering inflammation (C-reactive protein, CCL-28 IL-6, and IL-8). The mortality at 28 days, incidence of cerebrovascular accidents (CVA), and functional status were followed for three months. The levels of amyloid β1-40/β1-42 and NF-L were significantly elevated at all time points. The levels of τau, S100, KLK6, NRGN, and NCAM-1 were significantly elevated at 24 h. A cluster analysis demonstrated groupings around amyloids, KLK6, and NCAM-1. YKL-40, but not TDP-43, was significantly elevated across all time points. BDNF, apoE4, fetuin, and clusterin levels were significantly diminished long-term. IL-6 and IL-8 levles returned to baseline at t_3m. The levels of CRP, CCL-28, and Hsp-70 remained elevated. At 3 months, 8.2% of the patients experienced a stroke, with transfusion volume being a significant variable. Cardiac-surgery patients exhibited persistent peripheral and neuronal inflammation, blood vessel remodeling, and the depletion of neuroprotective factors 3 months post-procedure.

Association of electroencephalogram epileptiform discharges during cardiac surgery with postoperative delirium: An observational study

Background

Delirium is a frequent and serious complication following cardiac surgery involving cardiopulmonary bypass (CPB). Electroencephalography reflects the electrical activity of the cerebral cortex. The impact of electroencephalographic epileptiform discharges during cardiac surgery on postoperative delirium remains unclear. This study was designed to investigate the relationship between intraoperative epileptiform discharges and postoperative delirium in patients undergoing cardiac surgery.

Methods

A total of 76 patients who underwent cardiac surgery under CPB were included. The baseline cognitive status was measured before surgery. Electroencephalograms were monitored continuously from entry into the operating room to the end of surgery. The presence of delirium was assessed through the Confusion Assessment Method or the Confusion Assessment Method for the Intensive Care Unit on the first 3 days after surgery. Univariate and multivariate logistic regression analyses were performed to evaluate the association between epileptiform discharges and delirium.

Results

Delirium occurred in 31% of patients and epileptiform discharges were present in 26% of patients in the study. Patients with delirium had a higher incidence of epileptiform discharges (52.63% vs. 13.95%, P &lt; 0.001) and longer durations of anesthesia and CPB (P = 0.023 and P = 0.015, respectively). In addition, patients with delirium had a longer length of hospital stay and a higher incidence of postoperative complications. Multivariate logistic regression analysis showed that age and epileptiform discharges were significantly associated with the incidence of postoperative delirium [odds ratio, 4.75 (1.26–17.92), P = 0.022; 5.00 (1.34–18.74), P = 0.017, respectively].

Conclusions

Postoperative delirium is significantly related to the occurrence of epileptiform discharges during cardiac surgery.

Effect of Perioperative Dexmedetomidine Infusion on Postoperative Delirium in Elderly Patients Undergoing Oral and Maxillofacial Surgery: A Randomized Controlled Clinical Trial

Purpose

The aim of the study was to determine whether perioperative dexmedetomidine administration can improve postoperative delirium in elderly patients undergoing oral and maxillofacial surgery.

Patients and Methods

This was a prospective double-blind randomized controlled clinical trial conducted in Cangzhou Central Hospital from December 2021 to March 2022. Patients aged 65 and older underwent oral and maxillofacial surgery under general anesthesia. Eligible patients were randomly assigned to dexmedetomidine or control group. Dexmedetomidine was injected intravenously from 10 min before induction of anesthesia to 30 min before the end of surgery in dexmedetomidine group, while patients in the control group were given normal saline at the same rate during the same time period. The primary measurement indicators were the incidence and duration of delirium in the first five days after surgery. The secondary measurement indicators were Visual Analogue Score (VAS) for the first 24 hours following surgery, subjective sleep quality score within 24 hours postoperatively and intraoperative adverse reactions.

Results

One hundred and twenty patients were randomly assigned. Baseline characteristics were similar between two groups. The incidence and duration of postoperative delirium did not differ statistically between two groups (all P > 0.05). Compared with control group, VAS scores in dexmedetomidine group were significantly lower at 6, 12, and 24 hours after surgery (all P < 0.05); moreover, Richards-Campbell Sleep Questionnaire (RCSQ) results were significantly improved 1 day after surgery in dexmedetomidine group (P < 0.05). Dexmedetomidine-related adverse reactions were similar in both groups (P > 0.05).

Conclusion

Intravenous infusion of dexmedetomidine 10 min before induction of anesthesia to half an hour before the end of surgery did not improve postoperative delirium in elderly patients undergoing oral and maxillofacial surgery; however, dexmedetomidine may be associated with decreased postoperative pain and improved postoperative sleep quality.

Esketamine alleviates postoperative cognitive decline via stimulator of interferon genes/ TANK-binding kinase 1 signaling pathway in aged rats

BACKGROUND

Postoperative cognitive decline (POCD) is a common complication after surgery and anesthesia among the elderly. Yet the potential mechanism of POCD remains ambiguous, with limited therapeutic measures currently available. Ketamine has been reported to attenuate POCD after cardiac surgery. Herein, we tried to determine the effect of esketamine (the S-enantiomer of ketamine) on POCD and the possible molecular mechanisms.

METHODS

We investigated the effects of esketamine (10 mg/kg) on POCD using an exploratory laparotomy model in aged SD rats (24 months). Open field, novel object recognition, and morris water maze tests were performed on day 30 post-surgery. 24 h or 30 d post-surgery, brain tissue from the hippocampus and ventromedial prefrontal cortex (vmPFC) was harvested and subjected to histopathology and molecular biology analysis. During the in vitro experiment, primary astrocytes from the hippocampus and vmPFC were exposed to lipopolysaccharide (LPS) to investigate the pathological changes in astrocytes during the process of POCD.

RESULTS

Our results indicated that exploratory laparotomy could induce significant cognitive and memory decline, accompanied by A2-type astrocytes phenotype loss and increased expression of neuron Aβ-42, astrocytes GABA, stimulator of interferon genes (STING) and TANK-binding kinase 1 (TBK1). In addition, LPS exposure significantly decreased the mitochondrial membrane potential and upregulated the level of pyroptosis-associated proteins, including cleaved caspase-1 and IL-18. Notably, treatment with esketamine reversed these abnormalities in vivo and vitro. However, ADU-S100, a special STING activator, suppressed the protective effects of esketamine to a certain extent. Finally, C-176, an antagonist of STING, further enhanced the protective effects of esketamine against POCD.

CONCLUSIONS

Findings of our study suggest that esketamine can alleviate surgery-induced POCD in rats via inhibition of the STING/TBK1 signaling pathway.

Melatonin intervention to prevent delirium in hospitalized patients: A meta-analysis

BACKGROUND

Evaluation of the effectiveness of melatonin is necessary to prevent the development of delirium in hospitalized patients. Melatonin (N-acetyl-5-methoxytryptamine) is a hormone produced by the pineal gland of the brain from the amino acid tryptophan. Synthetic melatonin supplements have been used for various medical conditions, especially sleep-related diseases, and have proved to be successful.

AIM

To determine the effect of melatonin on the prevention of delirium in hospitalized patients.

METHODS

A literature search of the CNKI, Wanfang Database, VIP Database, China Biomedical Literature Database, PubMed, Embase, Cochrane Library, Web of Science, and other databases was conducted. The CNKI, Wanfang Database, VIP Database (VIP), and China Biomedical Literature Database were searched for Chinese studies, and PubMed, Embase, Cochrane Library, Web of Science and other databases were searched for international studies. It will be established in June 2021 in a randomized controlled trial (RCT) whether melatonin treatment for 6 mo prevents delirium in hospitalized patients. Literature screening, quality review, and data extraction were carried out using the Cochrane Manual 5.1.0 systematic evaluation method, and Stata 15.0 software and Review Manager 5.3 were used for meta-analysis and processing.

RESULTS

A total of 18 new RCT articles and 18 experimental subjects were identified. The results of the meta-analysis showed that following the occurrence of delirium, melatonin reduced the incidence of delirium in patients (RR = 0.69, 95%CI: 0.60-0.80), which is of significance, but heterogeneity was significant I² = 62%. Subgroup analysis was performed to examine the source of heterogeneity, and it was found that different patient types were the source of heterogeneity; the research on subgroup analysis was of high quality and homogeneous. To determine the reliability and robustness of the research results, a sensitivity analysis was carried out. The results showed that after excluding individual studies one by one, the effect size was still within 95%CI, which strengthened the reliability of the original meta-analysis results. Melatonin has a significant preventive effect on delirium in hospitalized medical patients [RR = 0.60, 95%CI: 0.47-0.76), P < 0.001].

CONCLUSION

Melatonin can reduce the rate of delirium in medical patients, and the role of melatonin in reducing the incidence of delirium in surgical patients and critical care unit patients requires further study.

Differential Cognitive Functioning and Benefit From Surgery in Patients Undergoing Coronary Artery Bypass Grafting and Carotid Endarterectomy

Background

Stenosing atherosclerosis in both coronary and carotid arteries can adversely affect cognition. Also their surgical treatments, coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA), are associated with cognitive changes, but the mechanisms of cognitive decline or improvement may not be the same. This study was designed to compare the cognitive profile and outcome in patients undergoing surgical treatment for coronary or carotid disease.

Methods

A total of 100 CABG patients and 44 CEA patients were recruited in two previously reported studies. They were subjected to a comprehensive neuropsychological examination prior to surgery and in the acute (3-8 days) and stable (3 months) phase after operation. A group of 17 matched healthy controls were assessed with similar intervals. We used linear mixed models to compare cognitive trajectories within six functional domains between the CABG, CEA and control groups. Postoperative cognitive dysfunction (POCD) and improvement (POCI) were determined with the reliable change index method in comparison with healthy controls.

Results

Before surgery, the CEA patients performed worse than CABG patients or healthy controls in the domains of executive functioning and processing speed. The CABG patients exhibited postoperative cognitive dysfunction more often than the CEA patients in most cognitive domains in the acute phase but had regained their performance in the stable phase. The CEA patients showed more marked postoperative improvement in executive functioning than the CABG group in the acute phase, but the difference did not reach significance in the stable phase.

Conclusion

Our findings suggest that anterior cerebral dysfunction in CEA patients impairs preoperative cognition more severely than global brain dysfunction in CABG patients. However, CEA may have more beneficial effects on cognition than CABG, specifically in executive functions mainly operated by the prefrontal lobes. In addition, the results underline that POCD is a heterogeneous condition and dependent on type of revascularization surgery.

Potential Neuroprotective Role of Sugammadex: A Clinical Study on Cognitive Function Assessment in an Enhanced Recovery After Cardiac Surgery Approach and an Experimental Study

Background

Postoperative cognitive dysfunction affects the quality of recovery, particularly affecting the elderly, and poses a burden on the health system. We hypothesize that the use of sugammadex (SG) could optimize the quality of postoperative cognitive function and overall recovery through a neuroprotective effect.

Methods

A pilot observational study on patients undergoing cardiac surgery with enhanced recovery after cardiac surgery (ERACS) approach, was designed to compare SG-treated (n = 14) vs. neostigmine (NG)-treated (n = 7) patients. The Postoperative Quality Recovery Scale (PQRS) was used at different times to evaluate cognitive function and overall recovery of the patients. An online survey among anesthesiologists on SG use was also performed. Additionally, an animal model study was designed to explore the effects of SG on the hippocampus.

Results

Sugammadex (SG) was associated with favorable postoperative recovery in cognitive domains particularly 30 days after surgery in patients undergoing aortic valve replacement by cardiopulmonary bypass and the ERACS approach; however, it failed to demonstrate a short-term decrease in length of intensive care unit (ICU) and hospital stay. The survey information indicated a positive appreciation of SG recovery properties. SG reverts postoperative memory deficit and induces the expression of anti-inflammatory microglial markers.

Conclusion

The results show a postoperative cognitive improvement by SG treatment in patients undergoing aortic valve replacement procedure by the ERACS approach. Additionally, experimental data from an animal model of mild surgery confirm the cognitive effect of SG and suggest a potential effect over glia cells as an underlying mechanism.

Intraoperative Glycemic Variability and Mean Glucose are Predictors for Postoperative Delirium After Cardiac Surgery: A Retrospective Cohort Study

Purpose

Postoperative delirium (POD) is a common but serious complication after cardiac surgery and is associated with various short- and long-term outcomes. In this study, we investigated the effects of intraoperative glycemic variability (GV) and other glycemic variables on POD after cardiac surgery.

Patients and Methods

A retrospective single-center cohort analysis was conducted using data from electronic medical record from 2018 to 2020. A total of 705 patients undergoing coronary artery bypass graft surgery and/or valve surgery, and/or aortic replacement surgery were included in the analysis. Intraoperative GV was assessed with a coefficient of variation (CV), which was defined as the standard deviation of five intraoperative blood glucose measurements divided by the mean. POD assessment was performed three times a day in the ICU and twice a day in the ward until discharge by trained medical staff. POD was diagnosed if any of the Confusion Assessment Method for the Intensive Care Unit was positive in the ICU, and the Confusion Assessment Method was positive in the ward. Multivariable logistic regression was used to identify associations between intraoperative GV and POD.

Results

POD occurred in 306 (43.4%) patients. When intraoperative glycemic CV was compared as a continuous variable, the delirium group had higher intraoperative glycemic CV than the non-delirium group (22.59 [17.09, 29.68] vs 18.19 [13.00, 23.35], p < 0.001), and when intraoperative glycemic CV was classified as quartiles, the incidence of POD increased as intraoperative glycemic CV quartiles increased (first quartile 29.89%; second quartile 36.67%; third quartile 44.63%; and fourth quartile 62.64%, p < 0.001). In the multivariable logistic regression model, patients in the third quartile of intraoperative glycemic CV were 1.833 times (OR 1.833, 95% CI: 1.132–2.967, p = 0.014), and patients in the fourth quartile of intraoperative glycemic CV were 3.645 times (OR 3.645, 95% CI: 2.235–5.944, p < 0.001) more likely to develop POD than those in the first quartile of intraoperative glycemic CV.

Conclusion

Intraoperative blood glucose fluctuation, manifested by intraoperative GV, is associated with POD after cardiac surgery. Patients with a higher intraoperative GV have an increased risk of POD.

Incidence of Postoperative Cognitive Dysfunction Following Inhalational vs Total Intravenous General Anesthesia: A Systematic Review and Meta-Analysis

Postoperative cognitive dysfunction (POCD) has been increasingly recognized as a contributor to postoperative complications. A consensus-working group recommended that POCD should be distinguished between delayed cognitive recovery, ie, evaluations up to 30 days postoperative, and neurocognitive disorder, ie, assessments performed between 30 days and 12 months after surgery. Additionally, the choice of the anesthetic, either inhalational or total intravenous anesthesia (TIVA) and its effect on the incidence of POCD, has become a focus of research. Our primary objective was to search the literature and conduct a meta-analysis to verify whether the choice of general anesthesia may impact the incidence of POCD in the first 30 days postoperatively. As a secondary objective, a systematic review of the literature was conducted to estimate the effects of the anesthetic on POCD between 30 days and 12 months postoperative. For the primary objective, an initial review of 1913 articles yielded ten studies with a total of 3390 individuals. For the secondary objective, four studies with a total of 480 patients were selected. In the first 30 days postoperative, the odds-ratio for POCD in TIVA group was 0.46 (95% CI = 0.26-0.81; p = 0.01), compared to the inhalational group. TIVA was associated with a lower incidence of POCD in the first 30 days postoperatively. Regarding the secondary objective, due to the small number of selected articles and its high heterogeneity, a metanalysis was not conducted. Given the heterogeneity of criteria for POCD, future prospective studies with more robust designs should be performed to fully address this question.

Influences of remote ischemic preconditioning on postoperative delirium and cognitive dysfunction in adults after cardiac surgery: a meta-analysis of randomized controlled trials

Background

Remote ischemic preconditioning (RIPC) has been suggested to confer neuroprotective effect. However, influences of RIPC on postoperative delirium (POD) and cognitive dysfunction (POCD) in adults after cardiac surgery are less known. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of RIPC on POD and POCD.

Methods

Relevant studies were obtained by search of PubMed, Embase, and Cochrane’s Library databases. A random-effect model was used to pool the results.

Results

Ten RCTs including 2303 adults who received cardiac surgery were included. Pooled results showed that RIPC did not significantly affect the incidence of POD (six RCTs, odds ratio [OR] 1.07, 95% confidence interval [CI] 0.81 to 1.40, P = 0.65) with no significant heterogeneity (I² = 0%). In addition, combined results showed that RIPC did not significantly reduce the incidence of POCD either (six RCTs, OR 0.64, 95% CI 0.37 to 1.11, P = 0.11) with moderate heterogeneity (I² = 44%). Sensitivity analysis by excluding one RCT at a time showed consistent results (P values all > 0.05).

Conclusions

Current evidence from RCTs did not support that RIPC could prevent the incidence of POD or POCD in adults after cardiac surgery. Although these findings may be validated in large-scale RCTs, particularly for the results of POCD, based on these findings, RIPC should not be routinely used as a preventative measure for POD and POCD in adult patients after cardiac surgery.

An Association Between C-Reactive Protein Levels and the Occurrence of Cognitive Dysfunction After Heart Valve Replacement

Background

Postoperative cognitive dysfunction (POCD) is defined as cognitive dysfunction related to inflammation after surgical procedures, which is common following cardiac surgery. Cognitive deficits are thought to result from a systemic inflammatory response. C-reactive protein (CRP) and other proinflammatory cytokines, which are released in response to inflammation, disrupt the blood–brain barrier and neurotransmission, resulting in POCD. This study aimed to determine the correlation between POCD and increased levels of CRP in patients who had undergone heart valve replacement.

Methods

This study comprised 32 patients with normal cognitive function undergoing heart valve replacement. The CRP levels were measured before surgery and on the second postoperative day, and cognitive function was examined via the Indonesian-adapted Montreal Cognitive Assessment (MOCA-INA) on the third postoperative day. Data were analyzed using Spearman correlation test.

Results

Of the 32 patients, 28 (87.5%) experienced POCD. The median level of CRP was 6.6 mg/dL (interquartile range: 4.0, 8.3 g/dL). According to Spearman correlation test, increased levels of CRP were significantly related to POCD following heart valve replacement (p = 0.003, r = 0.501). The receiver operating characteristic curve indicated that the CRP cutoff level was 3.345 mg/dL, and the sensitivity and specificity were 89.3% and 75%, respectively.

Conclusion

High expression level of CRP was correlated with POCD following heart valve replacement.

Predictors of cognitive dysfunction after cardiac surgery: a systematic review

AIMS

Postoperative cognitive dysfunction (POCD) is often experienced by cardiac surgery patients; however, it is not known if some groups of patients experience this more frequently or severely than others.The aim of this systematic review was to identify preoperative and postoperative predictors of cognitive dysfunction in adults following cardiac surgery.

METHODS AND RESULTS

Eight bibliographic databases were searched (January 2005 to March 2021) in relation to cardiac surgery and cognition. Studies including adult patients who had undergone open cardiac surgery and using a validated measurement of cognitive function were included. Full-text review for inclusion, quality assessment, and data extraction were undertaken independently by two authors.A total of 2870 papers were identified, of which 36 papers met the inclusion criteria and were included in the review. The majority were prospective observational studies [n = 28 (75.7%)]. In total, 61 independent predictors (45 preoperative and 16 postoperative) were identified as significant in at least one study; advancing age and education level appear important. Age has emerged as the most common predictor of cognitive outcome.

CONCLUSION

Although a number of predictors of POCD have been identified, they have inconsistently been reported as significantly affecting cognitive outcome. Consistent with previous research, our findings indicate that older patients and those with lower educational levels should be prioritized when developing and trialling interventions to improve cognitive function. These findings are less than surprising if we consider the methodological shortcomings of included studies. It is evident that further high-quality research exploring predictors of POCD is required.

Diagnosis and Risk Factors for Delirium in Elderly Patients in the Emergency Rooms and Intensive Care Unit of the National Geriatric Hospital Emergency Department: A Cross-Sectional Observational Study

Purpose

To diagnose delirium and identify risk factors for its development in elderly patients in the emergency department (ED) and intensive care units (ICU) at the National Geriatric Hospital (Vietnam).

Patients and Methods

A cross-sectional observational study was conducted with a convenience sample of non-surgical patients admitted to ED and ICU at Hanoi National Geriatric Hospital in Vietnam. In total, 163 patients met the selection criteria and were included in the study. Screening involved using the Confusion Assessment Method (CAM) and the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). The diagnosis was established according to the DSM-5 and ICD-10 codes.

Results

Delirium was found in a total of 106 (63.1%) patients. The factors significantly affecting its development were vision impairment (OR, 3.3; 95% CI, 1.5 to 7.4, P=0.003), hearing impairment (OR, 3.6; 95% CI, 1.77 to 7.36, P=0.0001), acute or chronic kidney failure (OR, 7.1; 95% CI, 2.05 to 6.39, P<0.001), respiratory disorders (OR, 2.7; 95% CI, 1.4 to 5.2, P=0.004), and malnutrition (OR, 9.17; 95% CI, 3.43–24.5, P=0.0001). The list also include the fall risk factors (OR, 12.2; 95% CI, 4.1–36.3, P=0.0001), frailty (OR, 8.35; 95% CI, 3.4–20.6, P=0.0001), activities of daily living (OR, 8.35; 95% CI, 3.4–20.6, P=0.0001), hyponatremia (OR, 2.48; 95% CI, 1.07 to 5.75, P=0.001), hypernatremia (OR, 13.1; 95% CI, 1.67 to 2.5, P=0.001), and treatment interventions. In addition, delirium was linked to the duration of ICU admission (OR, 6.53; 95% CI, 4.5–25.5, P < 0.0001).

Conclusion

The CAM/CAM-ICU diagnostic algorithm makes it possible to diagnose delirium successfully. The present study confirmed the role of several premorbid and triggering factors in the occurrence of delirium in elderly patients in ED and ICU. There is a need for further research into risk factors for delirium in elderly patients.

Regulatory role of microRNA-320 during off-pump coronary artery bypass grafting with dexmedetomidine adjunct anesthesia

The present study investigated the effects of dexmedetomidine on the expression level of microRNA-320 (miR-320) and neuroglobin (NGB) in patients undergoing off-pump coronary artery bypass grafting (OPCABG). A total of 40 patients undergoing OPCABG were recruited and randomly divided into the dexmedetomidine and normal saline groups (treated before anesthesia), respectively. The NGB levels in the blood samples before and after surgery were analyzed and compared. The CATH.a cells were cultured and induced with dexmedetomidine, and the NGB expression level was detected. CATH.a cells were treated with NGB and lipopolysaccharide (LPS), and the cell survival rate was determined. The miR-320 expression levels in the blood samples and dexmedetomidine-induced cells were detected. Dual-luciferase reporter assay was performed. Compared with control subjects, patients in the dexmedetomidine group had higher NGB levels in the blood. In the CATH.a cells, the dexmedetomidine treatment upregulated the NGB levels. Moreover, upon pre-incubation with NGB and LPS stimulation, dexmedetomidine elevated cell viability. Furthermore, miR-320 expression levels were significantly downregulated in the blood of patients in the dexmedetomidine group, as well as in the dexmedetomidine-induced cells. Dual-luciferase reporter assay confirmed that miRNA-320a directly targeted on NGB, and upregulated miRNA-320a in CATH.a cells decreased cell proliferation activity. Pre-administration of dexmedetomidine can decrease miR-320 expression level in the blood of patients undergoing OPCABG, stimulating the high expression of NGB and increasing the proliferation activity of neuronal cells, which may decrease the postoperative cognitive impairment.

Early Warning Value of ASL-MRI to Estimate Premorbid Variations in Patients With Early Postoperative Cognitive Dysfunctions

Background: Postoperative cognitive dysfunction (POCD) is a general complication following cardiac and major non-cardiac surgery amongst the elderly, yet its causes and mechanisms are still unknown. The present study aimed to detect whether regional cerebral blood flow (CBF) is altered in the brain before surgery in POCD patients compared with non-POCD (NPOCD) patients, thus, CBF variation may potentially predict the occurrence of early POCD.

Methods: Fifty patients scheduled for spinal stenosis surgery were enrolled in the study. All study participants completed a battery of neuropsychological tests (NPTs) by a well-trained neuropsychologist before the surgery and 1 week after the surgery. POCD was defined when the preoperative to postoperative difference of at least two of the NPTs’ |Z|-scores with reference to a control group exceeded 1.96. Pulsed arterial spin-labeling (ASL) MRI was scanned at least 1 day before surgery. The ASLtbx toolkit and SPM12 were applied to preprocess and correct the images, which were then normalized to the MNI brain template space to obtain standardized cerebral perfusion images.

Results: POCD was identified in 11 out of 50 patients (22%). The CBF of the right superior temporal lobe, right and left middle cingulate gyrus, and the right hippocampus, and parahippocampal gyrus in POCD group was lower than that in NPOCD group (P < 0.001). The CBF of the pars triangularis of inferior frontal gyrus in POCD group was higher than that in NPOCD group (P < 0.001).

Conclusions: These preliminary findings suggest that CBF premorbid alterations may happen in cognitively intact elderly patients that develop early POCD. Alterations of preoperative CBF might be a bio-marker for early POCD that can be detected by noninvasive MRI scans.

Optimizing cerebral perfusion and hemodynamics during cardiopulmonary bypass through cannula design combining in silico, in vitro and in vivo input

Cardiopulmonary bypass (CPB) is a standard technique for cardiac surgery, but comes with the risk of severe neurological complications (e.g. stroke) caused by embolisms and/or reduced cerebral perfusion. We report on an aortic cannula prototype design (optiCAN) with helical outflow and jet-splitting dispersion tip that could reduce the risk of embolic events and restores cerebral perfusion to 97.5% of physiological flow during CPB in vivo, whereas a commercial curved-tip cannula yields 74.6%. In further in vitro comparison, pressure loss and hemolysis parameters of optiCAN remain unaffected. Results are reproducibly confirmed in silico for an exemplary human aortic anatomy via computational fluid dynamics (CFD) simulations. Based on CFD simulations, we firstly show that optiCAN design improves aortic root washout, which reduces the risk of thromboembolism. Secondly, we identify regions of the aortic intima with increased risk of plaque release by correlating areas of enhanced plaque growth and high wall shear stresses (WSS). From this we propose another easy-to-manufacture cannula design (opti²CAN) that decreases areas burdened by high WSS, while preserving physiological cerebral flow and favorable hemodynamics. With this novel cannula design, we propose a cannulation option to reduce neurological complications and the prevalence of stroke in high-risk patients after CPB.

Decreased brain-derived neurotrophic factor levels may predict early perioperative neurocognitive disorder in patients undergoing coronary artery bypass surgery: A prospective observational pilot study

STUDY OBJECTIVE

To determine the prognostic value of the change in intraoperative BDNF (Brain-derived neurotrophic factor) levels during cardiac surgery with cardiopulmonary bypass (CPB) on early perioperative neurocognitive disorder (PND).

DESIGN

Prospective observational pilot study.

SETTING

The study was performed in the Medical Faculty Hospital, from January 2020 to August 2020.

PATIENTS

45 adult patients undergoing elective coronary artery bypass surgery (CABG) with CPB.

INTERVENTIONS

None.

MEASUREMENTS

Cognitive function was evaluated 1 day before and 4 days after the surgery. Serum BDNF levels were measured at four time points (T1: after induction; T2: with aortic cross-clamp; T3: without aortic cross-clamp; T4: 4 days after surgery) by enzyme-linked immunosorbent assay.

MAIN RESULTS

The incidence of PND was 37.8% four days after surgery. Serum BDNF (T2 and T4) levels were significantly lower in PND group compared to non- PND group (p = 0.003 and p = 0.016, respectively). Moreover, lactate, rSO₂ (regional cerebral oxygen saturation), aortic cross-clamp time, CPB duration, and the amount of blood transfusion differed between the groups. Logistic regression analysis identified serum BDNF-T2, age, cross-clamp time, and rSO₂-T2 as independent risk factors for PND. Based on the ROC analysis, the area under curve (AUC) of BDNF-T2 concentration for prediction of PND was 0.759 with sensitivity of 71.4% and specificity of 64.7% (p < 0.01).

CONCLUSION

Intraoperative BDNF serum levels may be a useful biomarker in predicting PND in patients undergoing CABG surgery. More comprehensive studies is needed in order to confirm the effect of decreasing intraoperative BDNF serum levels on the development of PND.

TRIAL REGISTRATION NUMBER

NCT04250935 www.clinicaltrials.gov.