Delirium in older patients undergoing aortic valve replacement: incidence, predictors, and cognitive prognosis

Does Comprehensive Geriatric Assessment Reduce the Incidence of Postoperative Delirium? A Quasi-experimental Study in Older Adults Undergoing Transcatheter Aortic Valve Implantation

Purpose

Postoperative delirium (POD) after transcatheter aortic valve implantation (TAVI) is frequent in older adults and associated with multiple negative outcomes including a higher mortality. We aimed to investigate whether a comprehensive geriatric assessment (CGA) prior to TAVI reduces the odds of POD and results in a positive change in self-care ability, intended to lay a foundation for future geriatric comanagement.

Patients and methods

We used a retrospective, single-center study with a quasi-experimental design enrolling patients aged 70 years and older undergoing CGA before elective TAVI, and a nonrandomized comparison group without preoperative CGA. Data on POD occurrence during the first 5 days after TAVI (primary outcome) and change in self-care ability index (SPI) between admission and discharge (secondary outcome) were collected from electronic health records and CGA data (exposure) by clinical assessment. To explore associations between (1) CGA and POD, and (2) CGA and SPI, multivariate logistic regression and linear regression models were applied adjusting for age, sex, BMI, and number of medications.

Results

Among 435 patients (mean age 81.0 ± 5.6 years, 43.6% women, median [IQR] SPI at baseline 40 [39, 40] points), POD incidence was 14.3% in the CGA group vs 18.8% in the non-CGA group (P 0.219). Undergoing CGA before TAVI was not associated with the odds for POD (OR: 1.15; 95%CI: 0.65-2.04) or improved SPI (P 0.073).

Conclusion

We observed no association of CGA prior to TAVI with POD incidence or postoperative self-care, highlighting the need for additional studies investigating the effect of POD preventive measures in older TAVI patients integrated into a comprehensive geriatric comanagement program.

Association between Neuron-Specific Enolase, Memory Function, and Postoperative Delirium after Transfemoral Aortic Valve Replacement

INTRODUCTION

Although transfemoral aortic valve replacement (TAVR) is a safe treatment for elderly patients with severe aortic valve stenosis, postoperative microembolism has been described. In this secondary endpoint analysis of the POST-TAVR trial, we aimed to investigate whether changes in neuron-specific enolase (NSE)-a biomarker of neuronal damage-are associated with changes in memory function or postoperative delirium (POD).

MATERIALS AND METHODS

This was a prospective single-center study enrolling patients undergoing elective TAVR. Serum NSE was measured before and 24 h after TAVR. POD was diagnosed using CAM-ICU testing. Memory function was assessed before TAVR and before hospital discharge using the "Consortium to Establish a Registry for Alzheimer's Disease" (CERAD) word list and the digit span task (DST) implemented in "∆elta-App".

RESULTS

Subjects' median age was 82 years (25th to 75th percentile: 77.5-85.0), 42.6% of subjects were women. CERAD scores significantly increased from pre- to post-TAVR, with p < 0.001. POD occurred in 4.4% (6/135) of subjects at median 2 days after TAVR. After TAVR, NSE increased from a median of 1.85 ng/mL (1.30-2.53) to 2.37 ng/mL (1.69-3.07), p < 0.001. The median increase in NSE was 40.4% (13.1-138.0) in patients with POD versus 17.3% (3.3-43.4) in those without POD (p = 0.17).

CONCLUSIONS

Memory function improved after TAVR, likely due to learning effects, with no association to change in NSE. Patients with POD appear to have significantly higher postoperative levels of NSE compared to patients without POD after TAVR. This finding suggests that neuronal damage, as indicated by NSE elevation, may not significantly impair assessed memory function after TAVR.

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.

Postoperative delirium in 47 379 individuals undergoing transcatheter aortic valve replacement: a systematic review and meta-analysis

Objective

The study aims to discuss the assessment methods used for the incidence of in-hospital postoperative delirium (IHPOD) in transcatheter aortic valve replacement (TAVR) patients and explore possible strategies for preventing and reducing postoperative complications in the geriatric population.

Methodology

An electronic search of PubMed, Embase, BioMedCentral, Google Scholar, and the Cochrane Central Register of Controlled Trials was conducted up to August 2021, to identify studies on the IHPOD following TAVR in patients above 70 years. The primary objective of the study was to determine the incidence of delirium following TAVR and procedures like transfemoral (TF) and non-TF approaches. The secondary objectives were to determine the incidence of stroke and incidence according to the confusion assessment method (CAM) diagnostic tool. The authors only included studies published in English and excluded patients with comorbidities and studies with inaccessible full-text.

Results

Among the selected 42 studies with 47 379 patients, the incidence of IHPOD following TAVR was 10.5% (95% CI: 9.2-11.9%, I2=95.82%, P<0.001). Incidence based on CAM was 15.6% (95% CI: 10.5-20.7%, I2=95.36%, P<0.001). The incidence of IHPOD after TF-TAVR was 9.3% (95% CI: 7.6-11.0%, I2=94.52%, P<0.001), and after non-TF TAVI was 25.3% (95% CI: 15.4-35.1%, I2=92.45%, P<0.001). The incidence of stroke was 3.7% (95% CI: 2.9-4.5%, I2=89.76%, P<0.001). Meta-regression analyses between mean age (P=0.146), logistic EuroSCORE (P=0.099), or percentage of participants treated using the TF approach (P=0.276) were nonsignificant while stroke (P=0.010) was significant. When considering these variables, the residual heterogeneity remained high indicating that other variables influence the heterogeneity.

Conclusion

IHPOD following TAVR was observed in 10.5% of individuals and in 15.6% using CAM. Its incidence was found to be three times higher after non-TF TAVR (25.3%) compared to TF TAVR (9.3%). Stroke showed an incidence of 3.7% after TAVR and was found to be significantly associated with the risk of developing delirium following TAVR. Further studies are needed to evaluate possible causes and risk factors responsible for delirium and to assess the role of anesthesia and cerebral embolic protection in preventing delirium after TAVR.

Postoperative delirium after transcatheter aortic valve replacement: An updated systematic review and meta-analysis

AIMS

To perform an updated systematic review and meta-analysis of postoperative delirium (POD) after transcatheter aortic valve replacement (TAVR).

METHODS

We conducted a systematic literature search of PubMed, Embase, and Cochrane Library databases from the time of the first human TAVR procedure in 2002 until December 24, 2021, which was supplemented by manual searches of bibliographies. Data were collected on incidence rates, risk factors, and/or associated mortality of POD after TAVR. Pooled analyses were conducted using random effects models to yield mean differences, odds ratios, hazard ratios, and risk ratios, with 95% confidence intervals.

RESULTS

A total of 70 articles (69 studies) comprising 413,389 patients were included. The study heterogeneity was substantial. The pooled mean incidence of POD after TAVR in all included studies was 9.8% (95% CI: 8.7%-11.0%), whereas that in studies using validated tools to assess for delirium at least once a day for at least 2 consecutive days after TAVR was 20.7% (95% CI: 17.8%-23.7%). According to the level of evidence and results of meta-analysis, independent preoperative risk factors with a high level of evidence included increased age, male sex, prior stroke or transient ischemic attack, atrial fibrillation/flutter, weight loss, electrolyte abnormality, and impaired Instrumental Activities of Daily Living; intraoperative risk factors included non-transfemoral access and general anesthesia; and acute kidney injury was a postoperative risk factor. POD after TAVR was associated with significantly increased mortality (pooled unadjusted RR: 2.20, 95% CI: 1.79-2.71; pooled adjusted RR: 1.62, 95% CI: 1.25-2.10), particularly long-term mortality (pooled unadjusted HR: 2.84, 95% CI: 1.91-4.23; pooled adjusted HR: 1.88, 95% CI: 1.30-2.73).

CONCLUSIONS

POD after TAVR is common and is associated with an increased risk of mortality. Accurate identification of risk factors for POD after TAVR and implementation of preventive measures are critical to improve prognosis.

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.

Effects of inflammation and oxidative stress on postoperative delirium in cardiac surgery

The past decade has witnessed unprecedented medical progress, which has translated into cardiac surgery being increasingly common and safe. However, complications such as postoperative delirium remain a major concern. Although the pathophysiological changes of delirium after cardiac surgery remain poorly understood, it is widely thought that inflammation and oxidative stress may be potential triggers of delirium. The development of delirium following cardiac surgery is associated with perioperative risk factors. Multiple interventions are being explored to prevent and treat delirium. Therefore, research on the potential role of biomarkers in delirium as well as identification of perioperative risk factors and pharmacological interventions are necessary to mitigate the development of delirium.

The Age-adjusted Charlson Comorbidity Index predicts post-operative delirium in the elderly following thoracic and abdominal surgery: A prospective observational cohort study

Background

Post-operative delirium (POD) presents as a serious neuropsychiatric syndrome in the elderly undergoing thoracic and abdominal surgery, which is mostly associated with poor prognosis. The Age-adjusted Charlson Comorbidity Index (ACCI) has been widely recognized as an independently predictive factor for overall survival rate and mortality in various surgeries. However, no studies demonstrated the potential relationship between ACCI and POD. The current study was to explore the correlation between ACCI and POD, and determine the predictive effect of ACCI on POD in the elderly after thoracic and abdominal surgery.

Materials and methods

Total 184 patients (≥60 years) who underwent thoracic and abdominal surgery from 2021.10 to 2022.5 were enrolled in this prospective observational cohort study. ACCI was calculated by weighting comorbidities and age. POD was diagnosed using Confusion Assessment Method (CAM) twice a day in the first 3 days after surgery. The Visual Analog Scale (VAS) was applied to measure pre-operative and post-operative pain at rest and in motion. All demographic and perioperative data were compared in patients with POD and without POD. ACCI and other variables were analyzed by univariate and multivariate logistic regression analysis. The characteristic curve of receiver operating characteristic (ROC) was used to further evaluate the accuracy of ACCI to predict POD.

Results

Post-operative delirium was diagnosed in 36 of 184 patients included in our study. The prevalence of POD in the elderly after thoracic and abdominal surgery was 19.6%. The outcomes by multivariate regression analysis showed the independent risk factors for POD were ACCI (OR: 1.834; 95%CI: 1.434–2.344; P < 0.001), pre-operative Mini-Mental State Examination (MMSE) scores (OR: 0.873; 95%CI: 0.767–0.994; P = 0.040), serum albumin (OR: 0.909; 95%CI: 0.826–1.000; P = 0.049) and pain scores in the post-operative third day (OR: 2.013; 95%CI: 1.459–2.778; P < 0.001). ACCI can predict POD more accurately with the largest area under curve (AUC) of 0.794 and sensitivity of 0.861, respectively.

Conclusion

Age-adjusted Charlson Comorbidity Index, pre-operative MMSE scores, serum albumin and post-operative pain were independently associated with POD in geriatric patients following thoracic and abdominal surgery. Moreover, ACCI may become an accurate indicator to predict POD early.

Postoperative delirium and neurocognitive disorders

PURPOSE OF REVIEW

Postoperative neurocognitive disorders (NCD) are significant causes of morbidity and mortality. In this paper, we will review our understanding and potential management of postoperative NCD.

RECENT FINDINGS

Postoperative delirium, delayed neurocognitive recovery and postoperative cognitive dysfunction (POCD) are recognized as a part of the continuous spectrum of postoperative NCD. Although the pathophysiology is still poorly understood, there is renewed focus on improving neurocognitive outcomes of aging surgical population. Novel methods of neurocognitive screening are developed and research in the prevention and management of NCD has gained traction.

SUMMARY

A spectrum of NCD exists in surgical patients ranging from postoperative delirium, delayed neurocognitive recovery, and POCD. Identification of patients at-risk for developing NCD can help target appropriate perioperative intervention. Also, specialized care teams and the implementation of standardized protocols are crucial for the successful management perioperative NCD. Finally, large, randomized, multicenter studies are needed to confirm benefits of preventive and treatment strategies.