The effects of anesthesia methods and anesthetics on postoperative delirium in the elderly patients: A systematic review and network meta-analysis

The Prevention and Treatment of Postoperative Delirium in the Elderly: A Narrative Systematic Review of Reviews

OBJECTIVES

Postoperative delirium (POD) is a common complication after major surgeries, posing significant challenges to patient recovery and outcomes, particularly among the elderly. A narrative systematic review was conducted to assess the clinical effectiveness and safety of interventions aimed at preventing and treating POD.

METHODS

A review of the literature from 2017 to September 29, 2023, was conducted using MEDLINE, EMBASE, and CINAHL. Systematic reviews, with or without meta-analyses, as well as practice guidelines, were included. Participants were adults, ≥60 years. The methodological quality of included reviews was appraised using AMSTAR 2.

RESULTS

After the search strategy identified 2295 references, 36 review studies were selected. Multicomponent interventions, incorporating both pharmacological and nonpharmacological approaches, demonstrate promise, particularly in hip fracture patients. Notably, dexmedetomidine emerges as a potential preventive measure, showing a notable reduction in delirium incidence following cardiac surgery. While several pharmacological interventions show potential, evidence remains inconclusive, necessitating further investigation. Similarly, varying anesthesia type and monitoring methods has mixed outcomes on delirium prevention. Despite methodological variations and quality appraisal limitations, this review underscores the importance of multicomponent interventions and the potential efficacy of dexmedetomidine in mitigating POD. Integration of evidence-based protocols into clinical practice is advocated to improve patient outcomes. However, the complex interplay between intervention components calls for further research to optimize delirium management strategies.

CONCLUSIONS

The strength of evidence associated with multicomponent interventions and dexmedetomidine use should require a genuine commitment from health care institutions to support their integration into efficient strategies to prevent and treat POD. Ongoing research is vital to uncover their full potential and refine clinical protocols, ultimately enhancing patient care outcomes.

Unraveling the impact of frailty on postoperative delirium in elderly surgical patients: a systematic review and meta-analysis

BACKGROUND

Frailty has been consistently implicated as a pivotal factor in the onset of delirium following anesthesia and surgery. Nonetheless, a comprehensive understanding of the relationship between frailty and delirium remains to be elucidated. This study addresses that knowledge gap.

METHODS

A comprehensive search of literature databases identified 43 relevant studies involving 14,441 participants. The studies were subjected to a rigorous quality assessment using the Newcastle-Ottawa Scale. Statistical analysis was conducted using Review Manager (v5.4.1), including subgroup and sensitivity analyses.

RESULTS

Meta-analysis revealed a significant association between preoperative physical frailty and postoperative delirium (pooled odds ratio: 2.47; 95% confidence interval: 2.04-2.99; I2 = 46.7%). The baseline frailty rate was 34.0% (4,910/14,441), while the overall incidence of postoperative delirium was 20% (2,783/14,441). Subgroup analyses based on characteristics such as race, frailty-assessment tools, and surgical types were conducted to explore potential sources of heterogeneity. This meta-analysis provided compelling evidence supporting a notable link between preoperative physical frailty and an increased risk of postoperative delirium in older surgical patients. Early identification through frailty screening can enable targeted interventions, potentially enhancing overall management and individualized treatment. Integrating frailty assessment into preoperative evaluation may improve predictive accuracy in surgical planning and anesthesia management.

CONCLUSIONS

Future research could focus on optimizing the integration of frailty assessment into preoperative protocols for timely intervention and improved patient outcomes.

TRIAL REGISTRATION

The review protocol was registered with PROSPERO (CRD42023390486), date of registration: Aug 11, 2023.

Perioperative Risk Factors for Postoperative Delirium in Non-dementia Older Patients after Non-cardiac Surgery and Anesthesia: A Prospective Study

BACKGROUND

To investigate the incidence and perioperative risk factors for postoperative delirium (POD) in non-dementia older patients who underwent anesthesia for non-cardiac surgery.

METHODS

This prospective cohort study was conducted on 195 non-dementia older patients, aged 60 years or older, who were hospitalized after non-cardiac surgery and anesthesia. The Confusion Assessment Method for the Intensive Care Unit was used to evaluate the occurrence of POD. Incidence of POD was reported. We conducted univariate and multivariate logistic regression to identify the risk factors associated with POD.

RESULTS

A total of 195 patients were enrolled; 172 completed the study. POD occurred in seven patients within three days after anesthesia, which is a 4.1% incidence of POD. Multivariate logistic analysis showed arrhythmia, coagulopathy, urinary comorbidity, minimum intraoperative heart rate, and minimum post-anesthesia care unit (PACU) pain score as independent risk factors for POD. A minimum PACU pain score >1 is the optimum cutoff pain score for developing POD, with a sensitivity of 85.7% and a specificity of 69.1%. The postoperative complication rate and in-hospital mortality were significantly higher for patients with POD compared to those without POD.

CONCLUSION

The incidence of POD in the study population is 4.1%. Arrhythmia, coagulopathy, urinary comorbidity, minimum intraoperative heart rate, and minimum PACU pain score were independent risk factors for POD. The minimum PACU pain score is the strongest independent risk factor of POD. POD is associated with increased postoperative complications and in-hospital mortality rates in non-dementia older patients.

The Implementation of Perioperative Geriatric Management Could Decrease the Incidence of Postoperative Delirium in the Elderly Undergoing Major Orthopedic Surgeries

OBJECTIVES

This study aimed to explore the association of perioperative geriatric management (PGM) in major orthopedic surgeries.

METHODS

One hundred seventy-five participants aged 75 and older were in-hospital patients who underwent major orthopedic surgery from September 2020 to September 2021, and they received PGM and necessary treatment for indicators with abnormal value (the PGM group). Another 175 participants in the control group only received the evaluation part of the PGM, recruited by filtering in the electronic medical record system from March 2016 to March 2017. The treatment included joint intervention of psychiatrists and rehabilitation physicians. For example, for patients at risk for falling, evaluation of inadequate blood volume, delirium, abnormal gait, and visual impairment should be performed. The logistic regression analysis was adopted to determine the association of PGM and postoperative delirium.

RESULTS

The prevalence of postoperative delirium among participants was 13.71%. Compared with the empirical treatment group, the postoperative delirium was significantly decreased (7.43% versus 14.29%) ( P <0.05). Compared with the control group, participants were in the PGM group were at lower risk of postoperative delirium, mainly attributed to these following factors: Charlson comorbidity index <5 [odds ratio (OR)=0.620; 95% CI: 0.010-0.623], mini cog >2 (OR=0.224; 95% CI: 0.061-0.824), Confusion Assessment Method score indicating low risk (OR=0.079; 95% CI: 0.010-0.623), nutritional risk screening scale <3 (OR=0.306; 95% CI: 0.095-0.989), and major adverse cardiovascular events <3 (OR=0.253; 95% CI: 0.073-0.720). After adjusting for the length of hospital stay and reason for hospitalization, the association between the parameters above and postoperative delirium is still significant ( P <0.05).

CONCLUSIONS

The implementation of the PGM could decrease the incidence of postoperative delirium significantly, which might contribute to improving the overall prognosis in elderly patients who underwent major orthopedic surgeries.

Knowledge mapping and research trends on perioperative neurocognitive disorder from 1990 to 2022: a bibliometric analysis

Introduction

Perioperative neurocognitive disorder (PND) has attracted consistently increasing attention worldwide. However, there are few bibliometric studies that systematically evaluate this field. This study aimed to visualize the knowledge structure and research trends in PND through bibliometrics to help understand the future development of basic and clinical research.

Methods

Literature related to PND in Web of Science and PubMed from 1990 to 2022 were collected through keywords retrospectively. Additionally, the source information, citation information, etc. of these publications were extracted. Finally, bibliometric analysis was performed by visualization software and statistical software.

Results

There were 2837 articles and reviews in total. An exponential rise in PND-related publications was observed. China had the most publication, followed by the US and Germany. The institution with the most output and citations was Harvard University (149 papers, 8966 citations). The most prominent author was Marcantonio Edward R with 66 publications and 5721 citations. The journal with the highest productivity for PND research was Frontiers in Aging Neuroscience followed by Anesthesia and Analgesia. Keywords were identified as six topics, including postoperative delirium, postoperative neurocognitive disorder, cardiac surgery, anaesthesia, orthopedic surgery, and dementia. According to keyword analysis, the most recent popular keywords in PND research were prevention, older patients, emergence delirium, orthopedic surgery, and dexmedetomidine.

Conclusions

Publications on PND are increasing at an alarming rate from 1990 to 2022. Current research and future trends will concentrate on the prevention and treatment of PND, as well as PND associated with orthopedic surgery in older adults.

Incidence of delirium after non-cardiac surgery in the Chinese elderly population: a systematic review and meta-analysis

Background

POD places a heavy burden on the healthcare system as the number of elderly people undergoing surgery is increasing annually because of the aging population. As a large country with a severely aging population, China's elderly population has reached 267 million. There has been no summary analysis of the pooled incidence of POD in the elderly Chinese population.

Methods

Systematic search databases included PubMed, Web of Science, EMBASE, Cochrane Library Databases, China Knowledge Resource Integrated Database (CNKI), Chinese Biomedical Database (CBM), WanFang Database, and Chinese Science and Technology Periodicals (VIP). The retrieval time ranged from the database's establishment to February 8, 2023. The pooled incidence of delirium after non-cardiac surgery was calculated using a random effects model. Meta-regression, subgroup, and sensitivity analyses were used to explore the source of heterogeneity.

Results

A total of 52 studies met the inclusion criteria, involving 18,410 participants. The pooled incidence of delirium after non-cardiac surgery in the elderly Chinese population was 18.6% (95% CI: 16.4-20.8%). The meta-regression results revealed anesthesia method and year of publication as a source of heterogeneity. In the subgroup analysis, the gender subgroup revealed a POD incidence of 19.6% (95% CI: 16.9-22.3%) in males and 18.3% (95% CI: 15.7-20.9%) in females. The year of publication subgroup analysis revealed a POD incidence of 20.3% (95% CI: 17.4-23.3%) after 2018 and 14.6 (95% CI: 11.6-17.6%) in 2018 and before. In the subgroup of surgical types, the incidence of hip fracture surgery POD was 20.7% (95% CI: 17.6-24.3%), the incidence of non-cardiac surgery POD was 18.4% (95% CI: 11.8-25.1%), the incidence of orthopedic surgery POD was 16.6% (95% CI: 11.8-21.5%), the incidence of abdominal neoplasms surgery POD was 14.3% (95% CI: 7.6-21.1%); the incidence of abdominal surgery POD was 13.9% (95% CI: 6.4-21.4%). The anesthesia methods subgroup revealed a POD incidence of 21.5% (95% CI: 17.9-25.1%) for general anesthesia, 15.0% (95% CI: 10.6-19.3%) for intraspinal anesthesia, and 8.3% (95% CI: 10.6-19.3%) for regional anesthesia. The measurement tool subgroup revealed a POD incidence of 19.3% (95% CI: 16.7-21.9%) with CAM and 16.8% (95% CI: 12.6-21.0%) with DSM. The sample size subgroup revealed a POD incidence of 19.4% (95% CI: 16.8-22.1%) for patients ≤ 500 and 15.3% (95% CI: 11.0-19.7%) for patients > 500. The sensitivity analysis suggested that the pooled incidence of postoperative delirium in this study was stable.

Conclusion

Our systematic review of the incidence of delirium after non-cardiac surgery in elderly Chinese patients revealed a high incidence of postoperative delirium. Except for cardiac surgery, the incidence of postoperative delirium was higher for hip fracture surgery than for other types of surgery. However, this finding must be further explored in future large-sample studies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: PROSPERO CRD42023397883.