The effect of preoperative cognitive impairment and type of vascular surgery procedure on postoperative delirium with associated cost implications

Infrainguinal bypass for limb salvage has comparable mortality and affords a better chance of home discharge than amputation among octogenarians

OBJECTIVE

Infrainguinal bypass for chronic limb-threatening ischemia in octogenarians is considered a high-risk procedure due to the presumed associated frailty of the patient population. However, the alternative, which is major amputation, may not be a better option. This study retrospectively compares the outcomes of bypass vs major amputation for functionally independent and partially dependent patients.

METHODS

Patients greater than and equal to 80 years old who underwent nonemergent infrainguinal bypasses for chronic limb-threatening ischemia presenting with rest pain/tissue loss were selected from the targeted American College of Surgeons National Surgical Quality Improvement Program database between 2011 and 2022. Patients with major amputations (Current Procedural Terminology codes 27,880, 27,882, 27,590, 27,592) for atherosclerosis by International Classification of Diseases-9/-10 codes were selected from the general database. We stratified the patients based on functional status (independent or partially dependent) and compared outcomes of bypass vs amputation within each group. Multivariable logistic regression was performed for 30-day mortality, major organ dysfunction, length of stay, and discharge destinations.

RESULTS

There were 2419 patients who underwent a bypass and 1326 patients who underwent an amputation in the independent functional group. Patients with bypass were generally healthier. Multivariable analysis revealed that having a bypass was associated with significantly higher major adverse cardiac events (adjusted odds ratio [aOR], 1.7; P < .01), bleeding requiring transfusion (aOR, 4.3; P < .01), and wound complications (aOR, 1.7; P < .01). There was no significant difference in mortality, renal complications, or sepsis. Additionally, bypass patients had longer operation time (P < .01) and return to the operating room (aOR, 2.7; P < .01). However, bypass patients were more likely to be discharged to home rather than to a facility (aOR, 4.2; P < .01). Similar outcomes were observed for partially dependent patients, except that bypass patients had a longer length of stay (12.40 ± 9.86 vs 10.78 ± 9.94 days; P < .01).

CONCLUSIONS

Bypass for limb salvage for octogenarians does incur higher morbidities than amputation but does not increase mortality. The immediate higher morbidities of bypass should be weighed against a better chance of home discharge, which could potentially imply less functional decline.

A Systematic Review of Cognitive Functioning and its Relationship to Outcomes Following Amputation Secondary to Vascular Etiology

Amputation is a major life event, impacting on all aspects of daily living, and has the goal of achieving maximal patient mobility and independence. The level of cognitive function of those patients who are assigned a prosthesis is an important consideration in the rehabilitation process. Therefore we set out to understand the relationship between cognitive functioning and functional and/or health outcomes following amputation secondary to a vascular condition. This systematic review searched five databases: PsycINFO, Cumulative index to nursing and allied health literature (CINAHL), Scopus, MEDLINE, and Web of Science for peer-reviewed English language articles that met the inclusion criteria. Two authors independently assessed suitability for inclusion, determined biases (Cochrane risk of bias assessment) and extracted data. Results are presented as associations determined on the balance of probabilities. A total of 14 studies were included, with a total of 6891 participants across six domains. Evidence of an association between cognitive function and prosthetic use, mobility and activities of daily living (ADLs) were found. Evidence revealed 83.3% association for cognition and mobility, 66.7% for cognition and ADL, and 62.5% for cognition and prosthetic use. The evidence was indeterminate for an association between cognitive function and living/discharge destination. There was insufficient weight of evidence to determine an association between cognitive function and general health or social participation. The associations found between cognitive function and prosthetic use, mobility and ADL highlight the need for cognitive assessment to form part of the postoperative pathway for vascular amputees.

Preoperative cognitive performance and its association with postoperative complications in vascular surgery patients: A prospective study

BACKGROUND

Cognitive impairment affects nearly half of vascular surgery patients, but its association with postoperative outcomes remains poorly understood. This study explores the link between preoperative cognitive performance and postoperative complications, including postoperative delirium, in vascular surgery patients.

METHODS

A prospective cohort study was conducted on vascular surgery patients aged ≥65. Preoperative cognitive performance was assessed using the Montreal Cognitive Assessment, and postoperative complications were evaluated using the Comprehensive Complication Index. The association was analyzed through multivariable logistic regression.

RESULTS

Among 110 patients (18.2 ​% female, mean age 73.8 ​± ​5.7 years), cognitive impairment was evident in 48.2 ​%. Of the participants, 29 (26.3 ​%) experienced postoperative complications, among which 11 (10 ​%) experienced postoperative delirium. The adjusted odds ratio for the association between cognitive performance and postoperative complications was 1.19 (95 ​% CI 1.02-1.38; p ​= ​0.02).

CONCLUSION

Worse preoperative cognitive performance correlated with increased odds of postoperative complications and postoperative delirium in vascular surgery patients.

Postoperative cognitive dysfunction: Review of pathophysiology, diagnostics and preventive strategies

Postoperative cognitive impairment is a common disorder after major surgery. Advances in medicine and treatment have resulted in an increasingly ageing population undergoing major surgical procedures. Since age is the most important risk factor for postoperative cognitive decline, it is not surprising that impairment of cognitive functions after surgery was recorded in almost a third of elderly patients. Postoperative cognitive dysfunction is part of the spectrum of postoperative cognitive impairment and researchers often confuse it with postoperative delirium and delayed neurocognitive recovery. This is the cause of great differences in the results of research that is focused on the incidence and possible prevention of postoperative cognitive dysfunction. In this review, we focused on current recommendations for a uniform nomenclature of postoperative cognitive impairment and diagnosis of postoperative cognitive dysfunction, the presumed pathophysiology of postoperative cognitive dysfunction and recommendations for its treatment and possible prevention strategies.

The utility of the Montreal cognitive assessment (MoCA) in detecting cognitive impairment in surgical populations - A systematic review and meta-analysis

STUDY OBJECTIVE

To determine the diagnostic accuracy of the Montreal Cognitive Assessment (MoCA) in detecting cognitive impairment (CI) and assess the association of MoCA scores with adverse postoperative outcomes in surgical populations.

DESIGN

Systematic review and meta-analysis.

SETTING

Perioperative setting.

PATIENTS

Adults undergoing elective or emergent surgery screened for CI preoperatively using the MoCA.

MEASUREMENTS

The outcomes included the diagnostic accuracy of the MoCA in screening for CI and the pooled prevalence of CI in various surgical populations. CI and its association with adverse events including delirium, hospital length-of-stay (LOS), postoperative complications, discharge destination, and mortality was determined.

MAIN RESULTS

Twenty-six studies (5059 patients, 18 non-cardiac studies, 8 cardiac studies) were included. With a MoCA cut-off score of <26, the prevalence of preoperative CI was 48% (95% CI: 41%-54%). The MoCA had 0.87 (95% CI: 0.79-0.93) sensitivity, 0.72 (95% CI: 0.62-0.80) specificity, PPV of 0.74 (95% CI: 0.65-0.81), and NPV of 0.86 (95% CI: 0.77-0.92) when validated against Petersen criteria, the Diagnostic and Statistical Manual of Mental Disorders, or the National Institute on Aging and the Alzheimer's Association criteria to identify CI. Using the MoCA as a screening tool, the LOS was 3.75 (95% CI: -0.03-7.53, P = 0.05, not significant) days longer in the CI group after non-cardiac surgeries and 3.33 (95% CI: 1.24-5.41, P < 0.002) days longer after cardiac surgeries than the non-cognitively impaired group.

CONCLUSIONS

MoCA had been validated in the surgical population. MoCA with a cut-off score of <26 was shown to have 87% sensitivity and 72% specificity in identifying CI. A positive screen in MoCA was associated with a 3-day longer hospital LOS in cardiac surgery in the CI group than in the non-CI group.

New Horizons in Peripheral Artery Disease

Peripheral artery disease (PAD) is the lower limb manifestation of systemic atherosclerotic disease. PAD may initially present with symptoms of intermittent claudication, whilst chronic limb-threatening ischaemia (CLTI), the end stage of PAD, presents with rest pain and/or tissue loss. PAD is an age-related condition present in over 10% of those aged ≥65 in high-income countries. Guidelines regarding definition, diagnosis and staging of PAD and CLTI have been updated to reflect the changing patterns and presentations of disease given the increasing prevalence of diabetes. Recent research has changed guidelines on optimal medical therapy, with low-dose anticoagulant plus aspirin recommended in some patients. Recently published randomised trials highlight where bypass-first or endovascular-first approaches may be optimal in infra-inguinal disease. New techniques in endovascular surgery have increased minimally invasive options for ever more complex disease. Increasing recognition has been given to the complexity of patients with CLTI where a high prevalence of both frailty and cognitive impairment are present and a significant burden of multi-morbidity and polypharmacy. Despite advances in minimally invasive revascularisation techniques and reduction in amputation incidence, survival remains poor for many with CLTI. Shared decision-making is essential, and conservative management is often appropriate for older patients. There is emerging evidence of the benefit of specialist geriatric team input in the perioperative management of older patients undergoing surgery for CLTI. Recent UK guidelines now recommend screening for frailty, cognitive impairment and delirium in older vascular surgery patients as well as recommending all vascular surgery services have support and input from specialist geriatrics teams.

Risk factors and associated outcomes of postoperative delirium after open abdominal aortic aneurysm repair

OBJECTIVE

Open abdominal aortic aneurysm repair (OAR) is a major vascular procedure that incurs a large physiologic demand, increasing the risk for complications such as postoperative delirium (POD). We sought to characterize POD incidence, identify delirium risk factors, and evaluate the effect of delirium on postoperative outcomes. We hypothesized that POD following OAR would be associated with increased postoperative complications and resource utilization.

METHODS

This was a retrospective study of all OAR cases from 2012 to 2020 at a single tertiary care center. POD was identified via a validated chart review method based on key words and Confusion Assessment Method assessments. The primary outcome was POD, and secondary outcomes included length of stay, non-home discharge, 90-day mortality, and 1-year survival. Bivariate analysis as appropriate to the data was used to assess the association of delirium with postoperative outcomes. Multivariable binary logistic regression was used to identify risk factors for POD and Cox regression for variables associated with worse 1-year survival.

RESULTS

Overall, 198 OAR cases were included, and POD developed in 34% (n = 67). Factors associated with POD included older age (74 vs 69 years; P < .01), frailty (50% vs 28%; P < .01), preoperative dementia (100% vs 32%; P < .01), symptomatic presentation (47% vs 27%; P < .01), preoperative coronary artery disease (44% vs 28%; P = .02), end-stage renal disease (89% vs 32%; P < .01) and Charlson Comorbidity Index score >4 (42% vs 26%; P = .01). POD was associated with 90-day mortality (19% vs 5%; P < .01), non-home discharge (61% vs 30%; P < .01), longer median hospital length of stay (14 vs 8 days; P < .01), longer median intensive care unit length of stay (6 vs 3 days; P < .01), postoperative myocardial infarction (7% vs 2%; P = .045), and postoperative pneumonia (19% vs 8%; P = .01). On multivariable analysis, risk factors for POD included older age, history of end-stage renal disease, lack of epidural, frailty, and symptomatic presentation. A Cox proportional hazards model revealed that POD was associated with worse survival at 1 year (hazard ratio, 3.8; 95% confidence interval, 1.6-9.0; P = .003).

CONCLUSIONS

POD is associated with worse postoperative outcomes and increased resource utilization. Future studies should examine the role of improved screening, implementation of delirium prevention bundles, and multidisciplinary care for the most vulnerable patients undergoing OAR.

Effect of pharmacist-led intervention protocol on preventing postoperative delirium after elective cardiovascular surgery

Postoperative delirium (PD) is an acute brain dysfunction, with a particularly high incidence after cardiovascular surgery. Pharmacist-led interventions show limited evidence in attenuating PD in cardiovascular surgery. In this retrospective cohort study, we aimed to clarify the risk factors of PD for cardiovascular surgery focused on pharmacotherapy and elucidate the effect of pharmacist-led intervention on the PD attenuation rate based on protocol-based pharmaceutical management (PBPM). This study included 142 adult patients who underwent elective valve replacement or valvuloplasty. The risk factors for PD were investigated using multivariate logistic regression analysis. Taking risk factors into consideration, a protocol was developed to discontinue benzodiazepines prescriptions by ward pharmacists, and replace with ramelteon and suvorexant if all the following factors apply: 1) number of medications ≥ 6 drugs, 2) number of doses to take ≥ 4 times, and 3) regular use of benzodiazepines or insomnia. Subsequently, the PD rate was compared during a period of two years and 6 months between the pre-PBPM (n = 39) and post-PBPM (n = 62). The PD rate for elective valve replacement or valvuloplasty was 25% (35/142). The adjusted odds ratio for polypharmacy was 3.3 (95% confidence interval: 1.2-8.9, p = 0.016), suggesting that preoperative risk assessment may be essential for patients with polypharmacy. The PD rate significantly decreased to 13% (8/62) in the post-PBPM group compared with 33% (13/39) in the pre-PBPM group (p = 0.014). There was a significant decrease in benzodiazepines use in post-PBPM compared with pre-PBPM (p = 0.026); however, the rate of ramelteon and orexin receptor antagonists use increased by PBPM introduction (p < 0.001). Although the present PBPM still requires further modification, it is simple and potentially useful for pharmacists to assess the risk of patients undergoing any elective cardiovascular surgery.

A framework for perioperative care for lower extremity vascular bypasses: A Consensus Statement by the Enhanced Recovery after Surgery (ERAS®) Society and Society for Vascular Surgery

The Society for Vascular Surgery and the Enhanced Recovery After Surgery (ERAS) Society formally collaborated and elected an international, multi-disciplinary panel of experts to review the literature and provide evidence-based suggestions for coordinated perioperative care for patients undergoing infrainguinal bypass surgery for peripheral artery disease. Structured around the ERAS core elements, 26 suggestions were made and organized into preadmission, preoperative, intraoperative, and postoperative sections.

Incidence and associations of hospital delirium diagnoses in 85,979 people with severe mental illness: A data linkage study

INTRODUCTION

Delirium is an acute neuro-psychiatric disturbance precipitated by a range of physical stressors, with high morbidity and mortality. Little is known about its relationship with severe mental illness (SMI).

METHODS

We conducted a retrospective cohort study using linked data analyses of the UK Clinical Practice Research Datalink (CPRD) and Hospital Episodes Statistics (HES) databases. We ascertained yearly hospital delirium incidence from 2000 to 2017 and used logistic regression to identify associations with delirium diagnosis in a population with SMI.

RESULTS

The cohort included 249,047 people with SMI with median follow-up time in CPRD of 6.4 years. A total of 85,979 patients were eligible for linkage to HES. Delirium incidence increased from 0.04 (95% CI 0.02-0.07) delirium associated admissions per 100 person-years in 2000 to 1.05 (95% CI 0.93-1.17) per 100 person-years in 2017, increasing most notably from 2010 onwards. Delirium was associated with older age at study entry (OR 1.05 per year, 95% CI 1.05-1.06), SMI diagnosis of bipolar affective disorder (OR 1.66, 95% CI 1.44-1.93) or other psychosis (OR 1.56, 95% CI 1.35-1.80) relative to schizophrenia, and more physical comorbidities (OR 1.08 per additional comorbidity of the Charlson Comorbidity Index, 95% CI 1.02-1.14). Patients with delirium received more antipsychotic medication during follow-up (1-2 antipsychotics OR 1.65, 95% CI 1.44-1.90; >2 antipsychotics OR 2.49, 95% CI 2.12-2.92).

CONCLUSIONS

The incidence of recorded delirium diagnoses in people with SMI has increased in recent years. Older people prescribed more antipsychotics and with more comorbidities have a higher incidence. Linked electronic health records are feasible for exploring hospital diagnoses such as delirium in SMI.

Activation of autophagy inhibits the activation of NLRP3 inflammasome and alleviates sevoflurane-induced cognitive dysfunction in elderly rats

AIMS/INTRODUCTION

As a common complication in elderly patients after surgery/anesthesia, postoperative cognitive dysfunction (POCD) is mainly characterized by memory, attention, motor, and intellectual retardation. Neuroinflammation is one of the most uncontroversial views in POCD. The sevoflurane-induced neurotoxicity has attracted widespread attention in recent years. However, its mechanism has not been determined. This study aimed to observe the effects of sevoflurane on cognitive function and the changes in inflammatory indices and autophagy protein expression in the prefrontal cortex in aged rats.

METHOD

Before the experiment, D-galactose was diluted with normal saline into a liquid with a concentration of 125 mg/kg and injected subcutaneously into the neck and back of rats for 42 days to establish the aging rat model. Morris water maze experiments were performed, including positioning navigation (5 days) and space exploration (1 day). The POCD model was established by 3.2% sevoflurane inhalation. The rats were treated with or without MCC950, a potent and selective nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inhibitor, followed by autophagy agonists and autophagy inhibitors. The expression levels of inflammasome-related protein NLRP3 and autophagy-related proteins LC3B and P62 were detected to test the behavior of rats with a water maze.

RESULTS

We found that sevoflurane exposure affected learning and working memory ability in aged rats. We also observed microglia activation in the prefrontal cortex. NLRP3 protein expression was significantly upregulated after sevoflurane inhalation. NLRP3 inflammasome activation induced increased expression and mRNA expression of cleaved Caspase-1 and inflammatory cytokines IL-1β and IL-18, and increased secretion of peripheral proinflammatory cytokines. The inhibitor MCC950 was used to improve cognitive ability and inflammation in rats and inhibit the secretion of cytokines. In addition, we demonstrated that significant inhibition of autophagy (decreased LC3-II/I and increased P62) was accompanied by increased activation of NLRP3 inflammasomes and more severe neural cell damage. However, autophagy inhibitor rapamycin administration to activate autophagy resulted in the inhibition of NLRP3 inflammasomes, ultimately attenuating neuronal injury.

CONCLUSIONS

The activation of autophagy suppressed the formation of NLRP3 inflammasomes. It also alleviated cognitive impairment in aged rats.

Predisposing and Precipitating Factors Associated With Delirium: A Systematic Review

Importance

Despite discrete etiologies leading to delirium, it is treated as a common end point in hospital and in clinical trials, and delirium research may be hampered by the attempt to treat all instances of delirium similarly, leaving delirium management as an unmet need. An individualized approach based on unique patterns of delirium pathophysiology, as reflected in predisposing factors and precipitants, may be necessary, but there exists no accepted method of grouping delirium into distinct etiologic subgroups.

Objective

To conduct a systematic review to identify potential predisposing and precipitating factors associated with delirium in adult patients agnostic to setting.

Evidence Review

A literature search was performed of PubMed, Embase, Web of Science, and PsycINFO from database inception to December 2021 using search Medical Subject Headings (MeSH) terms consciousness disorders, confusion, causality, and disease susceptibility, with constraints of cohort or case-control studies. Two reviewers selected studies that met the following criteria for inclusion: published in English, prospective cohort or case-control study, at least 50 participants, delirium assessment in person by a physician or trained research personnel using a reference standard, and results including a multivariable model to identify independent factors associated with delirium.

Findings

A total of 315 studies were included with a mean (SD) Newcastle-Ottawa Scale score of 8.3 (0.8) out of 9. Across 101 144 patients (50 006 [50.0%] male and 49 766 [49.1%] female patients) represented (24 015 with delirium), studies reported 33 predisposing and 112 precipitating factors associated with delirium. There was a diversity of factors associated with delirium, with substantial physiological heterogeneity.

Conclusions and Relevance

In this systematic review, a comprehensive list of potential predisposing and precipitating factors associated with delirium was found across all clinical settings. These findings may be used to inform more precise study of delirium's heterogeneous pathophysiology and treatment.

Postoperative outcomes in older surgical patients with preoperative cognitive impairment: A systematic review and meta-analysis

STUDY OBJECTIVE

To determine the effect of cognitive impairment (CI) and dementia on adverse outcomes in older surgical patients.

DESIGN

A systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs). Various databases were searched from their inception dates to March 8, 2021.

SETTING

Preoperative assessment.

PATIENTS

Older patients (≥ 60 years) undergoing non-cardiac surgery.

MEASUREMENTS

Outcomes included postoperative delirium, mortality, discharge to assisted care, 30-day readmissions, postoperative complications, and length of hospital stay. Effect sizes were calculated as Odds Ratio (OR) and Mean Difference (MD) based on random effect model analysis. The quality of included studies was assessed using the Cochrane Risk Bias Tool for RCTs and Newcastle-Ottawa Scale for observational cohort studies.

RESULTS

Fifty-three studies (196,491 patients) were included. Preoperative CI was associated with a significant risk of delirium in older patients after non-cardiac surgery (25.1% vs. 10.3%; OR: 3.84; 95%CI: 2.35, 6.26; I²: 76%; p < 0.00001). Cognitive impairment (26.2% vs. 13.2%; OR: 2.28; 95%CI: 1.39, 3.74; I²: 73%; p = 0.001) and dementia (41.6% vs. 25.5%; OR: 1.96; 95%CI: 1.34, 2.88; I²: 99%; p = 0.0006) significantly increased risk for 1-year mortality. In patients with CI, there was an increased risk of discharge to assisted care (44.7% vs. 38.3%; OR 1.74; 95%CI: 1.05, 2.89, p = 0.03), 30-day readmissions (14.3% vs. 10.8%; OR: 1.36; 95%CI: 1.00, 1.84, p = 0.05), and postoperative complications (40.7% vs. 18.8%; OR: 1.85; 95%CI: 1.37, 2.49; p < 0.0001).

CONCLUSIONS

Preoperative CI in older surgical patients significantly increases risk of delirium, 1-year mortality, discharge to assisted care, 30-day readmission, and postoperative complications. Dementia increases the risk of 1-year mortality. Cognitive screening in the preoperative assessment for older surgical patients may be helpful for risk stratification so that appropriate management can be implemented to mitigate adverse postoperative outcomes.

Postoperative delirium is an independent factor influencing the length of stay of elderly patients in the intensive care unit and in hospital

Purpose

Postoperative delirium (POD) is an often unrecognized adverse event in older people after surgery. The aim of this subgroup analysis of the PRe-Operative Prediction of postoperative DElirium by appropriate SCreening (PROPDESC) trial in patients aged 70 years and older was to identify preoperative risk factors and the impact of POD on length of stay (LOS) in intensive care unit (ICU) and hospital.

Methods

Of the total 1097 patients recruited at a German university hospital (from September 2018 to October 2019) in the PROPDESC prospective observational study, 588 patients aged 70 years and older (mean age 77.2 ± 4.7 years) were included for subgroup analysis. The primary endpoint POD was considered positive if one of the following tests were positive on any of the five postoperative visit days: Confusion Assessment Method for ICU (CAM-ICU), Confusion Assessment Method (CAM), 4'A's (4AT) and Delirium Observation Scale (DOS). Trained doctoral students carried out these visitations and additionally the nursing staff were interviewed for completion of the DOS. To evaluate the independent effect of POD on LOS in ICU and in hospital, a multi-variable linear regression analysis was performed.

Results

The POD incidence was 25.9%. The results of our model showed POD as an independent predictor for a prolonged LOS in ICU (36%; 95% CI 4–78%; < 0.001) and in hospital (22%; 95% CI 4–43%; < 0.001).

Conclusion

POD has an independent impact on LOS in ICU and in hospital. Based on the effect of POD for the elderly, a standardized risk screening is required.

Trail registration

German Registry for Clinical Studies: DRKS00015715.

The neuropsychological profile of delirium vulnerability: A systematic review and meta-analysis

Delirium is a common neurocognitive disorder in hospitalised older adults with substantial negative consequences. Impaired global cognition is a well-established delirium risk factor. However, poor performance on attention tests and higher intra-subject variability may be more sensitive delirium risk factors, given the disorder is characterised by a fluctuating course and attentional deficits. We systematically searched databases (Embase, PsycINFO, MEDLINE) and 44 studies satisfied inclusion criteria. Random-effects meta-analysis models showed poor performance in all cognitive domains except perception was significantly associated with incident delirium. Largest effects were for orientation (g=-1.20) and construction and motor performance (g=-0.60). These effects were no longer significant in the subgroup without pre-existing cognitive impairment, where executive functions and verbal functions and language skills were associated with incident delirium. A small, non-significant association between intra-subject variability and incident delirium was found (g=0.42). Cognitive domain specific tests may be quicker and more sensitive predictors of incident delirium. This pattern of neuropsychological findings supports the proposition that vulnerability for delirium manifests as a dysfunction of whole-brain information integration.

Prevalence of preoperative cognitive impairment in older surgical patients.: A systematic review and meta-analysis

STUDY OBJECTIVE

Older surgical patients with cognitive impairment are at an increased risk for adverse perioperative outcomes, however the prevalence of preoperative cognitive impairment is not well-established within this population. The purpose of this review is to determine the pooled prevalence of preoperative cognitive impairment in older surgical patients.

DESIGN

Systematic review and meta-analysis.

SETTING

MEDLINE (Ovid), PubMed (non-MEDLINE records only), Embase, Cochrane Central, Cochrane Database of Systematic Reviews, PsycINFO, and EMCare Nursing for relevant articles from 1946 to April 2021.

PATIENTS

Patients aged ≥60 years old undergoing surgery, and preoperative cognitive impairment assessed by validated cognitive assessment tools.

INTERVENTIONS

Preoperative assessment.

MEASUREMENTS

Primary outcomes were the pooled prevalence of preoperative cognitive impairment in older patients undergoing either elective (cardiac or non-cardiac) or emergency surgery.

MAIN RESULTS

Forty-eight studies (n = 42,498) were included. In elective non-cardiac surgeries, the pooled prevalence of unrecognized cognitive impairment was 37.0% (95% confidence interval [CI]: 30.0%, 45.0%) among 27,845 patients and diagnosed cognitive impairment was 18.0% (95% CI: 9.0%, 33.0%) among 11,676 patients. Within the elective non-cardiac surgery category, elective orthopedic surgery was analyzed. In this subcategory, the pooled prevalence of unrecognized cognitive impairment was 37.0% (95% CI: 26.0%, 49.0%) among 1117 patients, and diagnosed cognitive impairment was 17.0% (95% CI: 3.0%, 60.0%) among 6871 patients. In cardiac surgeries, the unrecognized cognitive impairment prevalence across 588 patients was 26.0% (95% CI: 15.0%, 42.0%). In emergency surgeries, the unrecognized cognitive impairment prevalence was 50.0% (95% CI: 35.0%, 65.0%) among 2389 patients.

CONCLUSIONS

A substantial number of surgical patients had unrecognized cognitive impairment. In elective non-cardiac and emergency surgeries, the pooled prevalence of unrecognized cognitive impairment was 37.0% and 50.0%. Preoperative cognitive screening warrants more attention for risk assessment and stratification.

Postoperative delirium after cardiac surgery of elderly patients as an independent risk factor for prolonged length of stay in intensive care unit and in hospital

Background

Postoperative delirium (POD) is a relevant and underdiagnosed complication after cardiac surgery that is associated with increased intensive care unit (ICU) and hospital length of stay (LOS). The aim of this subgroup study was to compare the frequency of tested POD versus the coded International Statistical Classification of Diseases and Related Health Problems (ICD) diagnosis of POD and to evaluate the influence of POD on LOS in ICU and hospital.

Methods

254 elective cardiac surgery patients (mean age, 70.5 ± 6.4 years) at the University Hospital Bonn between September 2018 and October 2019 were evaluated. The endpoint tested POD was considered positive, if one of the tests Confusion Assessment Method for ICU (CAM-ICU) or Confusion Assessment Method (CAM), 4 'A's Test (4AT) or Delirium Observation Scale (DOS) was positive on one day.

Results

POD occurred in 127 patients (50.0%). LOS in ICU and hospital were significantly different based on presence (ICU 165.0 ± 362.7 h; Hospital 26.5 ± 26.1 days) or absence (ICU 64.5 ± 79.4 h; Hospital 14.6 ± 6.7 days) of POD (p < 0.001). The multiple linear regression showed POD as an independent predictor for a prolonged LOS in ICU (48%; 95%CI 31–67%) and in hospital (64%; 95%CI 27–110%) (p < 0.001). The frequency of POD in the study participants that was coded with the ICD F05.0 and F05.8 by hospital staff was considerably lower than tests revealed by the study personnel.

Conclusion

Approximately 50% of elderly patients who underwent cardiac surgery developed POD, which is associated with an increased ICU and hospital LOS. Furthermore, POD is highly underdiagnosed in clinical routine.

Related Factors and Treatment of Postoperative Delirium in Old Adult Patients: An Integrative Review

“Postoperative delirium” is defined as delirium occurring in the hospital up to one week after a procedure or before discharge (whichever occurs first) that meets the DSM-5 diagnostic criteria. Objectives: To describe the risk factors related to this pathology and identify effective non-pharmacological forms of treatment. An integrative review of the available literature was performed. The search results considered included all quantitative studies published between 2011 and 2019 in both English and Spanish. A total of 117 studies were selected. Advanced age was identified as the principal risk factor for postoperative delirium. Nursing interventions appear to be the key to preventing or reducing the seriousness of delirium after an anaesthetic episode. The aetiology of postoperative delirium remains unknown, and no treatment exists to eliminate this pathology. The role of nursing staff is fundamental in the prevention, diagnosis, and management of the pathology.

Impaired cognitive performance on MoCA testing at discharge in elderly patients following day endoscopy and its relationship to preoperative mild cognitive impairment

In patients admitted to hospital, preoperative mild cognitive impairment predicts postoperative complications. The effect of mild cognitive impairment on discharge readiness among the day stay surgery population is unknown. Our aims were to determine the incidence of impaired cognitive performance at discharge after day stay endoscopy and whether pre-existing mild cognitive impairment was associated with its development. A single-centre cohort study of elective day stay endoscopy patients was undertaken. Over a three-month period, data were collected from 69 patients aged 65 years and over. Patients were cognitively assessed on admission and discharge using the Montreal cognitive assessment tool and the three-minute diagnostic confusion assessment method. At baseline, patients who scored 1.5 or more standard deviations below age-adjusted levels on the Montreal cognitive assessment tool in conjunction with a subjective memory complaint were classified as having mild cognitive impairment. At discharge, patients were classified as having impaired cognitive performance if there was a reduction in the Montreal cognitive assessment tool score by at least two points. We also assessed delirium and subsyndromal delirium at discharge using the three-minute diagnostic confusion assessment method. We identified mild cognitive impairment in 23 patients (33.3%) on admission, and impaired performance on the Montreal cognitive assessment tool test at discharge in 35 (50.7%) patients. There was no association between mild cognitive impairment on admission and impaired cognitive performance at discharge (50.0% versus 51.1%, P = 0.94). This study demonstrates that evidence of impaired cognitive performance on the Montreal cognitive assessment tool testing is present after day stay endoscopy in over 50% of elderly patients, but this is not associated with preoperative cognitive status.

Association between ankle brachial index and development of postoperative intensive care unit delirium in patients with peripheral arterial disease

Patients with vascular diseases are prone to developing postoperative delirium (POD). Ankle brachial index (ABI) is a non-invasive clinical indicator of lower-extremities peripheral arterial disease (PAD) and has been identified as an indicator of cognitive impairment. We investigated the association between ABI and POD. 683 PAD patients who underwent elective leg arterial bypass surgery between October 1998 and August 2019 were collected for retrospective analysis. Demographic information, comorbidities, preoperative ABI and the Rutherford classification within one month prior to surgery were obtained. POD was assessed using the Confusion assessment method -intensive care unit. Logistic regression and receiver operating characteristics (ROC) curve analysis were used to assess the association between ABI and POD. The mean value of ABI was significantly lower in patients with POD than it was those without POD. Older age, more medical comorbidities, longer length of surgery, decreased ABI, and higher Rutherford class were all significantly associated with POD. The area under ROC (0.74) revealed that ABI below 0.35 was associated with development of POD. Lower preoperative ABI was associated with POD in PAD patients who underwent arterial bypass surgery.

The Role of Microglia in Perioperative Neuroinflammation and Neurocognitive Disorders

The aseptic trauma of peripheral surgery activates a systemic inflammatory response that results in neuro-inflammation; the microglia, the resident immunocompetent cells in the brain, are a key element of the neuroinflammatory response. In most settings microglia perform a surveillance role in the brain detecting and responding to “invaders” to maintain homeostasis. However, microglia have also been implicated in producing harm possibly by changing its phenotype from its beneficial, anti-inflammatory state (termed M2) into an injurious pro-inflammatory state (termed M1); it is likely that there are intermediates states between these polar phenotypes and some consider that a gradient exists with a number of intermediates, rather than a strict dichotomy between M1 and M2. In the pro-inflammatory phenotypes, microglia can disrupt synaptic plasticity such as long- term potentiation that can result in disorders of learning and memory of the type observed in Peri-operative Neurocognitive Disorders. Therefore, investigators have sought strategies to prevent microglia from provoking this adverse event in the perioperative period. In preclinical studies microglia can be depleted by removing trophic factors required for its maintenance; subsequent repopulation with a more beneficial microglial phenotype may result in memory enhancement, improved sensory motor function, as well as suppression of neuroinflammatory and oxidative stress pathways. Another approach consists of preventing microglial activation using the non-specific P38 MAP kinase blockers such as minocycline. Perhaps a more physiologic approach is the use of inhibitors of potassium (K⁺) channels that are required to convert the microglia into an active state. In this context the specific K⁺ channels that are implicated are termed Kv1.3 and KCa3.1 and high selective inhibitors for each have been developed. Data are accumulating demonstrating the utility of these K⁺ channel blockers in preventing Perioperative Neurocognitive Disorders.

Risk Factors for Delirium after Vascular Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Vascular surgery is considered a risk factor for the development of postoperative delirium (POD). In this systematic review we provide a report on the incidence and risk-factors of POD after vascular surgery.

METHODS

A systematic literature search was conducted using Pubmed with the MeSH terms and key words "delirium" or "confusion", "vascular surgery procedures" and "risk factors or "risk assessment". Studies were selected for review after meeting the following inclusion criteria: vascular surgery, POD diagnosed using validated screening tools, and DSM-derived criteria to assess delirium. A meta-analysis was performed for each endpoint if at least two studies could be combined.

RESULTS

Sixteen articles met the abovementioned criteria. The incidence of delirium ranged from 5% to 39%. Various preoperative risk factors were identified that is, age (Random MD 3.96, CI 2.57-5.35), hypertension (Fixed OR 1.30, CI 1.05-1.59), diabetes mellitus (Random OR 2.15, CI 1.30-3.56), hearing impairment (Fixed OR 1.89, CI 1.28-2.81), history of cerebrovascular incident or transient ischemic attack (Fixed OR 2.20, CI 1.68-2.88), renal failure (Fixed OR 1.61, CI 1.19-2.17), and pre-operative low haemoglobin level (fixed MD -0.76, CI -1.04 to -0.47). Intra-operative risk factors were duration of surgery (Random MD 15.68; CI 2.79-28.57), open aneurysm repair (Fixed OR 4.99, CI 3.10-8.03), aortic cross clamping time (fixed MD 7.99, CI 2.56-13.42), amputation surgery (random OR 3.77, CI 2.13-6.67), emergency surgery (Fixed OR 4.84, CI 2.81-8.32) and total blood loss (Random MD 496.5, CI 84.51-908.44) and need for blood transfusion (Random OR 3.72, CI 1.57-8.80). Regional anesthesia on the other hand, had a protective effect. Delirium was associated with longer ICU and hospital length of stay, and more frequent discharge to a care facility.

CONCLUSIONS

POD after vascular surgery is a frequent complication and effect-size pooling supports the concept that delirium is a heterogeneous disorder. The risk factors identified can be used to either design a validated risk factor model or individual preventive strategies for high-risk patients.

Prevalence of Cognitive Impairment in Individuals with Vascular Surgical Pathology: a Systematic Review and Meta-Analysis

OBJECTIVE

A significant proportion of vascular surgery patients may have undiagnosed cognitive impairment; however, its true prevalence and impact on outcomes are unknown. The aim of this review was to estimate the prevalence of cognitive impairment among individuals with clinically significant vascular surgical pathology and investigate its associations with post-operative outcomes in those undergoing vascular surgery.

METHODS

MEDLINE, EMBASE, EMCare, CINAHL, PsycINFO, and Scopus were searched for relevant studies. Included studies assessed cognitive function among individuals with either symptomatic vascular surgical pathology, or disease above threshold for intervention, using a validated cognitive assessment tool. The primary outcome measure was prevalence of cognitive impairment. Secondary outcomes included incidence of post-operative delirium (POD). Two reviewers independently extracted relevant study data and assessed risk of bias (ROBINS-E or RoB 2 tool). Prevalence (%) of cognitive impairment was calculated for individual studies and presented with 95% confidence intervals (CI). Prevalence data from comparable studies were pooled using the Mantel-Haenszel method (random effects model) for separate vascular disease types. Certainty of effect estimates was assessed using the GRADE criteria.

RESULTS

Twenty-four studies (2 564 participants) were included in the systematic review, and nine studies (1 310 participants) were included in the meta-analyses. The prevalence of cognitive impairment was 61% (95% CI 48 - 74; 391 participants; low certainty) in studies including multiple vascular surgical pathologies, 38% (95% CI 32 - 44; 278 participants; very low certainty) in carotid artery disease, and 19% (95% CI 10 - 33; 641 participants; low certainty) in those with intermittent claudication. Lower cognitive assessment scores were associated with POD (five studies; 841 participants), but data were not suitable for pooling.

CONCLUSION

Screening elective vascular surgery patients for cognitive impairment may be appropriate given its high prevalence, and the association of worse cognition with POD, among individuals with clinically significant vascular surgical pathology.

The economic cost of delirium: A systematic review and quality assessment

INTRODUCTION

This review aims to systematically identify and appraise the methodological quality of claims on the cost of delirium; and discuss challenges and opportunities for improvements in the precision of the estimates.

METHODS

Searches of scientific papers and gray literature were performed up until June 2020. The Larg and Moss checklist was used to assess the methodological quality of the included studies.

RESULTS

After deduplication, the search identified 317 potentially relevant articles, of which 17 articles were eligible for inclusion. After adjusting for inflation and common currency, the cost of delirium ranged between $806 and $24,509 (in 2019 US$).

DISCUSSION

This review found significant variation among the cost estimates and methodological quality. There has been limited focus on dementia as a sequela of delirium in terms of economic implications, but recent evidence suggests cost implications of delirium may be 52% higher when dementia is considered.

Estimates of Geriatric Delirium Frequency in Noncardiac Surgeries and Its Evaluation Across the Years: A Systematic Review and Meta-analysis

OBJECTIVES

Delirium is an acute neuropsychiatric syndrome associated with poor outcomes. Older adults undergoing surgery have a higher risk of manifesting perioperative delirium, particularly those having associated comorbidities. It remains unclear whether delirium frequency varies across surgical settings and if it has remained stable across the years. We conducted a systematic review to (1) determine the overall frequency of delirium in older people undergoing noncardiac surgery; (2) explore factors explaining the variability of the estimates; and (3) determine the changing of the estimates over the past 2 decades.

DESIGN

Systematic review and meta-analysis. Literature search was performed in MEDLINE, PubMed, ISI Web of Science, EBSCO, ISRCTN registry, ScienceDirect, and Embase in January 2020 for studies published from 1995 to 2020.

SETTING

Noncardiac surgical settings.

PARTICIPANTS

Forty-nine studies were included with a total of 26,865 patients screened for delirium.

METHODS

We included observational and controlled trials reporting incidence, prevalence, or proportion of delirium in adults aged ≥60 years undergoing any noncardiac surgery requiring hospitalization. Data extracted included sample size, reported delirium frequencies, surgery type, anesthesia type, delirium diagnosis method, length of hospitalization, and year of assessment. (PROSPERO registration no.: CRD42020160045).

RESULTS

We found an overall pooled frequency of preoperative delirium of 17.9% and postoperative delirium (POD) of 23.8%. The POD estimates increased between 1995 and 2020 at an average rate of 3% per year. Pooled estimates of POD were significantly higher in studies not excluding patients with lower cognitive performance before surgery (28% vs 16%) and when general anesthesia was used in comparison to local, spinal, or epidural anesthesia (28% vs 20%).

CONCLUSIONS AND IMPLICATIONS

Type of anesthesia and preoperative cognitive status were significant moderators of delirium frequency. POD in noncardiac surgery has been increasing across the years, suggesting that more resources should be allocated to delirium prevention and management.

Endovascular abdominal aortic aneurysm repair in a centenarian

As the general population ages, there will be an increasing number of vascular patients in their 90s and older. However, geriatric patients have historically been turned down for abdominal aortic aneurysm repair despite high aneurysm-related mortality in the unrepaired. Herein, we describe the perioperative considerations and the successful, uncomplicated operative course of a 100-year-old woman who underwent an elective endovascular aortic aneurysm repair for an expanding 5.3-cm abdominal aortic aneurysm. Given a suitable patient, there is acceptable risk profile of an endovascular approach, even in centenarians.

Effect of baseline cognitive impairment on association between predicted propofol effect site concentration and Bispectral index or sedation score

Background

This study determined whether the relationship between predicted propofol effect site concentration (Ce) and observer’s assessment of alertness/sedation scale (OAA/S) or Bispectral Index (BIS) was similar comparing cognitively intact vs impaired patients undergoing hip fracture repair with spinal anesthesia and sedation.

Methods

Following informed consent baseline mini-mental status exam (MMSE), Clinical Dementia Rating (CDR) and geriatric depression scale (GDS) were obtained. Intraoperatively OAA/S, BIS, and propofol (timing and exact amounts) administered were recorded. Cerebrospinal fluid was collected for Alzheimer’s (AD) biomarkers. Mean Ce level (AvgCe) during surgery was calculated using the area under the Ce measurement series from incision to closure, divided by surgical time. Average OAA/S (AvgOAA/S), and BIS (AvgBIS) were similarly calculated. Pearson correlations of AvgCe with AvgOAA/S and AvgBIS were calculated overall and by CDR. Nonparametric locally weighted scatterplot smoothing (LOWESS) fits of AvgOAA/S and AvgBIS on AvgCe were produced, stratified by CDR. Multivariable regression incorporating baseline cognitive measurements or AD biomarkers assessed AvgOAA/S or AvgBIS associations with AvgCe.

Results

In 186 participants AvgBIS and AvgOAA/S correlated with AvgCe (Pearson ρ = − 0.72; p < 0.0001 and Pearson ρ = − 0.81; p < 0.0001, respectively), and remained unchanged across CDR levels. Association patterns of AvgOAA/S or AvgBIS on AvgCe guided by LOWESS fits and modeled through regression, were similar when stratified by CDR (p = 0.16). Multivariable modeling found no independent effect on AvgBIS or AvgOAA/S by MMSE, CDR, GDS, or AD biomarkers after accounting for AvgCe.

Conclusions

When administering sedation in conjunction with spinal anesthesia, cognitive impairment does not affect the relationship between predicted propofol AvgCe and AvgOAA/S or AvgBIS.

Dementia is associated with increased mortality and poor patient-centered outcomes after vascular surgery

OBJECTIVE

Dementia has been associated with increased complications and mortality in orthopedics and other surgical specialties, but has received limited attention in vascular surgery. Therefore, we evaluated the association of dementia with surgical outcomes for elderly patients with Medicare who underwent a variety of open and percutaneous vascular surgery procedures.

METHODS

We reviewed claims data from the Centers for Medicare and Medicaid Services for beneficiaries enrolled in Medicare Part A fee-for-service insurance from January 1, 2011, to December 31, 2011, who underwent inpatient vascular surgery. Only the first surgery during the first admission was considered for analysis. Traditional outcomes (30- and 90-day mortality, intensive care admission, complications, length of stay) and patient-centered outcomes (discharge to home, extended skilled nursing facility [SNF] stay, time at home) were adjusted for patient and procedure characteristics using multilevel linear or logistic regression as appropriate. All analyses were performed using SAS (v9.4, SAS Institute Inc, Cary, NC).

RESULTS

Our study included 210,918 patients undergoing vascular surgery, of whom 27,920 carried a diagnosis of dementia. The average age of the entire cohort was 75.74 years, and 55.43% were male. Patients with dementia were older and had higher rates of comorbidities compared with patients without a dementia diagnosis. The three most common defined classes of intervention excluding miscellaneous ones were cerebrovascular, peripheral arterial, and aortic cases, which jointly accounted for 53.15% of cases. Among all cases, 56.62% were open. Emergent/urgent cases were more frequent amongst those with dementia (60.66% vs 37.93%; P < .001). After adjustment, patients with dementia had increased odds of 30-day mortality (odds ratio [OR], 1.21; P < .0001) and 90-day mortality (OR, 1.63; P < .0001), extended SNF stay (OR, 3.47; P < .0001), and longer hospital length of stay (8.29 days vs 5.41 days; P < .001). They were less likely to be discharged home (OR, 0.31; P < .0001) and spent a lower fraction of time at home after discharge (63.29% vs 86.91%; P < .001). Intensive care admission and inpatient complications were similar between the two groups.

CONCLUSIONS

Dementia is associated with poor traditional outcomes, including increased 30- and 90-day mortality and longer hospital lengths of stay in this large national patient sample. It is also associated with worse patient-centered outcomes, including substantially lower discharge rates to home, less time spent at home after discharge, and higher rates of extended stay in a SNF. These data should be used to counsel patients facing vascular surgery to provide goal-concordant care, particularly to patients with dementia.