Delirium in older people after proximal femoral fracture repair: Role of a preoperative screening cognitive test

Incidence of postoperative delirium in older adults undergoing surgical procedures: A systematic literature review and meta-analysis

BACKGROUND

With the increase in life expectancy around the globe, the incidence of postoperative delirium (POD) among older people (≥65 years) is growing. Previous studies showed a wide variation in the incidence of POD, from 4% to 53%, with a lack of specific evidence about the incidence of POD by specific surgery type among older people. The aim of this systematic review and meta-analysis was to determine the incidence of POD by surgery type within populations 65 years and over.

METHODS

Databases including PubMed, Cochrane library, Embase, and CINAHL were searched until October 2020. Due to the relatively higher number of meta-analyses undertaken in this area of research, a streamlined systematic meta-analysis was proposed.

RESULTS

A total of 28 meta-analyses (comprising 284 individual studies) were reviewed. Data from relevant individual studies (n = 90) were extracted and included in the current study. Studies were grouped into eight surgery types and the incidence of POD for orthopedic, vascular, spinal, cardiac, colorectal, abdominal, urologic, and mixed surgeries was 20%, 14%, 13%, 32%, 14%, 30%, 10%, and 26%, respectively. POD detection instruments were different across the studies, with Confusion Assessment Method (CAM & CAM-ICU) being the most frequently adopted.

LINKING EVIDENCE TO ACTION

This study showed that POD incidence in older people undergoing surgery varied widely across surgery type. The more complex surgeries like cardiac and abdominal surgeries were associated with a higher risk of POD. This highlights the need to include the level of surgery complexity as a risk factor in preoperative assessments.

Preoperative Risk Factors Associated with Increased Incidence of Postoperative Delirium: Systematic Review of Qualified Clinical Studies

Postoperative delirium (POD) is an acute alteration of mental state, characterized by reduced awareness and attention, occurring up to five postoperative days after recovery from anesthesia. Several original studies and reviews have identified possible perioperative POD risk factors; however, there is no comprehensive review of the preoperative risk factors in patients diagnosed with POD using only validated diagnostic scales. The aim of this systematic review was to report the preoperative risk factors associated with an increased incidence of POD in patients undergoing non-cardiac and non-brain surgery. The reviewed studies included original research papers that used at least one validated diagnostic scale to identify POD occurrence for more than 24 h. A total of 6475 references were retrieved from the database search, with only 260 of them being suitable for further review. Out of the 260 reviewed studies, only 165 that used a validated POD scale reported one or more preoperative risk factors. Forty-one risk factors were identified, with various levels of statistical significance. The extracted risk factors could serve as a preoperative POD risk assessment workup. Future studies dedicated to the further evaluation of the specific preoperative risk factors' contributions to POD could help with the development of a weighted screening tool.

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.

Fascia iliaca compartment block as a preoperative analgesic in elderly patients with hip fractures - effects on cognition

BACKGROUND

Impaired cognition is a major risk factor for perioperative delirium. It is essential to provide good pain control in patients with hip fractures and especially important in patients with severely impaired cognitive status, as they receive less pain medication, have poorer mobility, poorer quality of life and higher mortality than patients with intact cognition. The purpose of this study was to examine the association between preoperative pain management with nerve blocks and cognitive status in patients with hip fractures during the perioperative period.

METHODS

One hundred and twenty-seven patients with hip fractures participating in a double-blind, randomised, controlled trial were included in this study. At hospital admission, a low-dose fascia iliaca compartment block (FICB) was administered as a supplement to regular analgesia. Cognitive status was registered on arrival at hospital before FICB and on the first postoperative day using the Short Portable Mental Status Questionnaire.

RESULTS

Changes in cognitive status from arrival at hospital to the first postoperative day showed a positive, albeit not significant, trend in favour of the intervention group. The results also showed that patients with no or a moderate cognitive impairment received 50% more prehospital pain medication than patients with a severe cognitive impairment. FICB was well tolerated in patients with hip fractures.

CONCLUSION

Fascia iliaca compartment block given to patients with hip fractures did not affect cognitive status in this study. Patients with a cognitive impairment may receive inadequate pain relief after hip fracture and this discrimination needs to be addressed in further studies.

TRIAL REGISTRATION

EudraCT number 2008-004303-59 date of registration: 2008-10-24.

Codex (Cognitive Disorders Examination) Decision Tree Modified for the Detection of Dementia and MCI

Many cognitive screening instruments are available to assess patients with cognitive symptoms in whom a diagnosis of dementia or mild cognitive impairment is being considered. Most are quantitative scales with specified cut-off values. In contrast, the cognitive disorders examination or Codex is a two-step decision tree which incorporates components from the Mini-Mental State Examination (MMSE) (three word recall, spatial orientation) along with a simplified clock drawing test to produce categorical outcomes defining the probability of dementia diagnosis and, by implication, directing clinician response (reassurance, monitoring, further investigation, immediate treatment). Codex has been shown to have high sensitivity and specificity for dementia diagnosis but is less sensitive for the diagnosis of mild cognitive impairment (MCI). We examined minor modifications to the Codex decision tree to try to improve its sensitivity for the diagnosis of MCI, based on data extracted from studies of two other cognitive screening instruments, the Montreal Cognitive Assessment and Free-Cog, which are more stringent than MMSE in their tests of delayed recall. Neither modification proved of diagnostic value for mild cognitive impairment. Possible explanations for this failure are considered.

Best Practices for Postoperative Brain Health: Recommendations From the Fifth International Perioperative Neurotoxicity Working Group

As part of the American Society of Anesthesiology Brain Health Initiative goal of improving perioperative brain health for older patients, over 30 experts met at the fifth International Perioperative Neurotoxicity Workshop in San Francisco, CA, in May 2016, to discuss best practices for optimizing perioperative brain health in older adults (ie, >65 years of age). The objective of this workshop was to discuss and develop consensus solutions to improve patient management and outcomes and to discuss what older adults should be told (and by whom) about postoperative brain health risks. Thus, the workshop was provider and patient oriented as well as solution focused rather than etiology focused. For those areas in which we determined that there were limited evidence-based recommendations, we identified knowledge gaps and the types of scientific knowledge and investigations needed to direct future best practice. Because concerns about perioperative neurocognitive injury in pediatric patients are already being addressed by the SmartTots initiative, our workshop discussion (and thus this article) focuses specifically on perioperative cognition in older adults. The 2 main perioperative cognitive disorders that have been studied to date are postoperative delirium and cognitive dysfunction. Postoperative delirium is a syndrome of fluctuating changes in attention and level of consciousness that occurs in 20%-40% of patients >60 years of age after major surgery and inpatient hospitalization. Many older surgical patients also develop postoperative cognitive deficits that typically last for weeks to months, thus referred to as postoperative cognitive dysfunction. Because of the heterogeneity of different tools and thresholds used to assess and define these disorders at varying points in time after anesthesia and surgery, a recent article has proposed a new recommended nomenclature for these perioperative neurocognitive disorders. Our discussion about this topic was organized around 4 key issues: preprocedure consent, preoperative cognitive assessment, intraoperative management, and postoperative follow-up. These 4 issues also form the structure of this document. Multiple viewpoints were presented by participants and discussed at this in-person meeting, and the overall group consensus from these discussions was then drafted by a smaller writing group (the 6 primary authors of this article) into this manuscript. Of course, further studies have appeared since the workshop, which the writing group has incorporated where appropriate. All participants from this in-person meeting then had the opportunity to review, edit, and approve this final manuscript; 1 participant did not approve the final manuscript and asked for his/her name to be removed.

Risk factors for postoperative delirium following hip fracture repair in elderly patients: a systematic review and meta-analysis

BACKGROUND

No formal systematic review or meta-analysis was performed up to now to summarize the risk factors of delirium after hip surgery.

AIMS

The present study aimed to quantitatively and comprehensively conclude the risk factors of delirium after hip surgery in elderly patients.

METHODS

A search was applied to CNKI, Embase, Medline, and Cochrane central database (all up to August 2015). All studies assessing the risk factors of delirium after hip surgery in elderly patients without language restriction were reviewed, and qualities of included studies were assessed using the Newcastle-Ottawa Scale. Data were pooled and a meta-analysis was completed.

RESULTS

A total of 24 studies were selected, which altogether included 5364 patients with hip fracture. One thousand and ninety of them were cases of delirium occurred after surgery, suggesting the accumulated incidence of 24.0 %. Results of meta-analyses showed that elderly patients with preoperative cognitive impairment [odds ratio (OR) 3.21, 95 % confidence interval (CI) 2.26-4.56), advanced age (standardized mean difference 0.50, 95 % CI 0.33-0.67), living in an institution (OR 2.94; 95 % CI 1.65-5.23), heart failure (OR 2.46; 95 % CI 1.72-3.53), total hip arthroplasty (OR 2.21; 95 % CI 1.16-4.22), multiple comorbidities (OR 1.37; 95 % CI 1.12-1.68) and morphine usage (OR 3.01; 95 % CI 1.30-6.94) were more likely to sustain delirium after hip surgery. Females were less likely to develop delirium after hip surgery (OR 0.83; 95 % CI 0.70-0.98).

CONCLUSIONS

Related prophylaxis strategies should be implemented in elderly patients involved with above-mentioned risk factors to prevent delirium after hip surgery.

Factors predicting incidence of post-operative delirium in older people following hip fracture surgery: a systematic review and meta-analysis

OBJECTIVE

Delirium is one of the most common complications following hip fracture surgery in older people. This study identified pre- and peri-operative factors associated with the development of post-operative delirium following hip fracture surgery.

METHODS

Published and unpublished literature were searched to identify all evidence reporting variables on patient characteristics, on-admission, intra-operative and post-operative management assessing incident delirium in older people following hip fracture surgery. Pooled odds ratio (OR) and mean difference of those who experienced delirium compared to those who did not were calculated for each variable. Evidence was assessed using the Downs and Black appraisal tool and interpreted using the GRADE approach.

RESULTS

A total of 6704 people (2090 people with post-operative delirium) from 32 studies were analysed. There was moderate evidence of nearly a two-times greater probability of post-operative delirium for those aged 80 years and over (OR: 1.77; 95% CI: 1.09, 2.87), whether patients lived in a care institution pre-admission (OR: 2.65; 95% CI: 1.79, 3.92), and a six-times greater probability of developing post-operative delirium with a pre-admission diagnosis of dementia (OR: 6.07, 95% CI: 4.84, 7.62). There was no association with intra-operative variables and probability of delirium.

CONCLUSION

Clinicians treating people with a hip fracture should be vigilant towards post-operative delirium if their patients are older, have pre-existing cognitive impairment and poorer overall general health. This is also the case for those who experience post-operative complications such as pneumonia or a urinary tract infection. Copyright © 2017 John Wiley & Sons, Ltd.

The influence of a history of clinical depression on peri-operative outcomes in elective total shoulder arthroplasty: a ten-year national analysis

AIMS

Depression can significantly affect quality of life and is associated with higher rates of medical comorbidities and increased mortality following surgery. Although depression has been linked to poorer outcomes following orthopaedic trauma, total joint arthroplasty and spinal surgery, we wished to examine the impact of depression in elective total shoulder arthroplasty (TSA) as this has not been previously explored.

PATIENTS AND METHODS

The United States Nationwide Inpatient Sample (NIS) was used to identify patients undergoing elective TSA over a ten-year period. Between 2002 and 2012, 224 060 patients underwent elective TSA.

RESULTS

Among the identified patients who had undergone TSA, 12.4% had a diagnosis of a history of depression. A diagnosis of depression was twice as common in women compared with men (16.0% vs 8.0%, p < 0.001), and more frequent in those with low income and Medicaid insurance (p < 0.001). A diagnosis of depression was an independent risk factor for post-operative delirium (odds ratio (OR) 2.29, p < 0.001), anaemia (OR 1.65, p < 0.001), infection (2.09, p = 0.045) and hospital discharge to a placement other than home (OR 1.52, p < 0.001) CONCLUSION: A history of clinical depression is present in 12.4% of patients undergoing elective TSA and the disease burden is projected to increase further in the future. Depression is often underdiagnosed and pre-operative screening and appropriate peri-operative management of patients is encouraged.

TAKE HOME MESSAGE

The awareness that clinical depression is associated with increased complications following total shoulder arthroplasty provides physicians an opportunity for early intervention in this at-risk population. Cite this article: Bone Joint J 2016;98-B:818-24.

Preoperative Cognitive and Frailty Screening in the Geriatric Surgical Patient: A Narrative Review

PURPOSE

The identification of older patients who may have deficits in cognitive or functional domains will become more pressing as increasing numbers of these patients present for preoperative evaluations. The number of older adults with deficiencies in these areas is projected to grow, and more of these patients will present for assessment in preoperative clinics with the expectation that surgeries will be performed.

METHODS

We review current outcomes data for preoperative cognitive impairment and frailty.

FINDINGS

We point to a number of directions research is taking as systems for the prevention of postoperative cognitive and functional decline are being developed. We also discuss the current status of screening and examine potential instruments that can be used in the setting of the preanesthesia clinic.

IMPLICATIONS

Clinicians may anticipate that geriatric screening tools focused on cognitive and functional domains will play a direct role in the ongoing evolution of presurgical assessment and triage.

Sensitivity and specificity of the animal fluency test for predicting postoperative delirium

BACKGROUND

Preoperative cognitive impairment is a major risk factor for postoperative delirium. We therefore investigated the prognostic significance and feasibility of administering a brief cognitive screen before surgery.

METHODS

Patients > 65 yr of age undergoing hip, knee, or spine surgery were enrolled. A 60-sec cognitive screen, the animal fluency test (AFT), was administered preoperatively. Postoperative delirium was measured using a chart-based tool previously validated using criteria from the Confusion Assessment Method.

RESULTS

Of the 362 patients satisfying the inclusion/exclusion criteria, 199 (55%) underwent the AFT. Among them, 57 patients (29%) had an AFT score < 15, and 38 patients (19%, 95% confidence interval [CI]: 14 to 25%) developed postoperative delirium as measured by chart review. Patients with scores of < 15 were more likely to develop postoperative delirium than those who scored ≥ 15 (54% vs 5%, P < 0.01). A multiple logistic regression, with postoperative delirium as the dependent variable, identified an AFT score of < 15 (odds ratio 20.1, 95% CI: 7.9 to 51.4) and high American Society of Anesthesiologists classification (odds ratio 3.5, 95% CI: 1.3 to 9.2) as independent predictors.

CONCLUSIONS

The AFT is a potentially useful brief cognitive screen for identifying patients at risk of developing postoperative delirium. Limited participation by eligible participants in this study, however, raises questions about how useful and feasible systematic administration of the test is. Large studies using prospective measurement of postoperative delirium are indicated to validate our results.