Identifying Older Adults at Risk of Delirium Following Elective Surgery: A Systematic Review and Meta-Analysis

Exploratory randomised trial of tranexamic acid to decrease postoperative delirium in adults undergoing lumbar fusion-a trial stopped early

Background

Postoperative delirium may be mediated by systemic inflammation and neuroinflammation. By inhibiting the proinflammatory actions of plasmin, tranexamic acid (TXA) may decrease postoperative delirium. To explore this hypothesis, we modified an ongoing randomised trial of TXA on blood loss, adding measures of delirium, cognition, systemic inflammation, and astrocyte activation.

Methods

Adults undergoing elective posterior lumbar fusion randomly received intraoperative i.v. TXA (n=43: 10 mg kg-1 loading dose, 2 mg kg-1 h-1 infusion) or placebo (n=40). Blood was collected before surgery and 24 h after surgery (n=32) for biomarkers (cytokines and S100B). Participants had twice daily delirium assessments (n=65). Participants underwent four measures of cognitive function before surgery and during post-discharge follow-up.

Results

Postoperative blood loss was ∼38% less in the TXA group compared with the placebo group with medians of 128 and 207 ml level-1, respectively, P=0.013. Total blood loss in the TXA and placebo groups did not differ with medians of 305 and 333 ml level-1, respectively, P=0.472. Delirium incidence in the TXA group (7/32=22%) was not significantly less than in the placebo group (11/33=33%); P=0.408, effect size =-0.258 (95% confidence interval -0.744 to 0.229).

Conclusions

A potential 33% relative decrease in postoperative delirium incidence justifies an adequately powered clinical trial to determine if intraoperative TXA decreases delirium in adults undergoing lumbar fusion.

Clinical trial registration

NCT04272606.

Perioperative neurocognitive dysfunction and role of dexmedetomidine in radical colon cancer surgery in elderly patients

This article explored the application of dexmedetomidine (Dex), a highly selective alpha-2 agonist, in managing postoperative cognitive dysfunction (POCD) in elderly patients undergoing radical colon cancer surgery. Aging is associated with a progressive decline in physiological functions and an increased risk of adverse surgical outcomes, including POCD, which encompasses many neurocognitive disorders that manifest during the perioperative period. The aging population is at a higher risk for POCD, which can lead to prolonged hospital stays, delayed recovery, and increased healthcare costs. Dex has neuroprotective, opioid-sparing, and sympatholytic properties, which reduces the incidence and severity of POCD. Dex was introduced for sedation in patients receiving mechanical ventilation but has since been adopted in anesthesia due to its multifaceted benefits. Its application extends to sedation, analgesia, maintenance of anesthesia, and controlling delirium. Its neuroprotective and anti-inflammatory effects have been explored in managing POCD. This article discussed the broad range of patient and procedure-related risk factors for POCD. Early identification and intervention are crucial to prevent the progression of POCD, which can have severe physical, psychological, and economic consequences. The article underscored the importance of a multidisciplinary approach in managing POCD, involving the optimization of comorbidities, depth of anesthesia monitoring, hemodynamic stability, and cerebral oxygenation monitoring.

Establishment and validation of a nomogram of postoperative delirium in patients undergoing cardiac surgery: a retrospective study of MIMIC-IV

OBJECTIVE

To establish a nomogram for predicting the occurrence of postoperative delirium (POD) in patients undergoing cardiac surgery.

MATERIALS AND METHODS

Data from 5379 patients were retrieved from the Medical Information Mart for Intensive Care (MIMIC-IV) database and divided into a training set and a validation set at a 7:3 ratio. Multivariate logistic regression was conducted to identify independent predictors and establish nomograms to predict the occurrence of POD. The area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA) were used to evaluate the accuracy and reliability of the model.

RESULTS

A total of 5379 post-cardiac surgery patients were included in the study, with 258 patients in the training set and 113 patients in the validation set developing POD. Multivariate logistic regression analysis identified seven independent predictors: age, partial pressure of carbon dioxide (PCO2), glucose, white blood cell count (Wbc), stroke, anemia and chronic obstructive pulmonary disease (COPD). The prediction model demonstrated good discrimination, with an AUC of 0.702 (95 CI: 0.671-0.734) in the training set and 0.711 (95 CI: 0.7662 - 0.761) in the validation set. The calibration curve of the prediction model closely matched the ideal curve in both the training set and the validation set. In addition, the DCA curve demonstrated that the nomogram has better clinical applicability.

CONCLUSION

We constructed a nomogram for the personalized prediction of delirium in post-cardiac surgery patients, demonstrating satisfactory performance and clinical utility. This tool may help clinicians initiate preventive interventions for POD.

Association between periprocedural cerebral desaturation during transcatheter aortic valve implantation and postprocedural delirium: a prospective observational study

BACKGROUND

The aim of this study was to investigate whether the level of decrease in cerebral oxygen saturation during the valve placement phase of the transcatheter aortic valve implantation (TAVI) procedure under sedation has an effect on postoperative delirium (POD).

METHODS

The study initially assessed 50 patients between the ages of 50 and 90 years with an indication for TAVI by the cardiac team. Regional cerebral oxygen saturation (rScO2) was measured using Near-infrared spectroscopy (NIRS) before the procedure (T1), during surgical field sterilization (T2), catheter placement (T3), wire manipulation (T4), valve placement (T5) and access site artery repair (T6). Confusion Assessment Method for The Intensive Care Unit (ICU-CAM) test was performed on intensive care unit and the presence of POD was questioned. Patients were divided into two groups as those without POD (Group 1) and those with POD (Group 2).

RESULTS

The study was completed with 41 patients in total. While POD was present in 12 (29.3%) of the patients evaluated intensive care unit, POD was not observed in 29 (70.7%) patients. The rScO2 value measured at T5 was significantly lower in Group 2 compared to Group 1 (p < 0.001).

CONCLUSIONS

In our study, the rate of POD after TAVI was as high as 29.3%. Low rScO2 during valve placement was associated with delirium. Our findings indicate that NIRS devices could be a useful tool for assessing the risk of POD during the TAVI procedure; however, further research is needed to validate their routine clinical use.

Recent developments in delirium after oral and maxillofacial free-flap reconstruction

Postoperative delirium (POD), a common complication following surgery and anesthesia, is particularly prone to occur after reconstruction surgery in the oral and maxillofacial region. The occurrence of POD seriously affects the incidence of postoperative complications, the survival of free flaps, the length of hospital stays, and brings great pain to patients and their families, and even increases perioperative mortality. Currently, a large number of studies have reported on the risk factors for POD after oral and maxillofacial free-flap reconstruction. Multiple independent risk factors have been identified, including age, history of excessive alcohol consumption, and perioperative nutritional status. This review summarizes the relevant literature and hopes to provide insights for the prevention of POD in high-risk patients.

Exploratory Randomised Trial of Tranexamic Acid to Decrease Postoperative Delirium in Adults Undergoing Lumbar Fusion: A trial stopped early

Background

Postoperative delirium may be mediated by perioperative systemic- and neuro-inflammation. By inhibiting the pro-inflammatory actions of plasmin, tranexamic acid (TXA) may decrease postoperative delirium. To explore this hypothesis, we modified an ongoing randomised trial of TXA, adding measures of postoperative delirium, cognitive function, systemic cytokines, and astrocyte activation.

Methods

Adults undergoing elective posterior lumbar fusion randomly received intraoperative intravenous TXA (n=43: 10 mg kg-1 loading dose, 2 mg kg-1 h-1 infusion) or Placebo (n=40). Blood was collected pre- and at 24 h post-operatively (n=32) for biomarkers of systemic inflammation (cytokines) and astrocyte activation (S100B). Participants had twice daily delirium assessments using the 3-minute diagnostic interview for Confusion Assessment Method (n=65). Participants underwent 4 measures of cognitive function preoperatively and during post-discharge follow-up.

Results

Delirium incidence in the TXA group (7/32=22%) was not significantly less than in the Placebo group (11/33=33%); P=0.408, absolute difference=11%, relative difference=33%, effect size = -0.258 (95% CI -0.744 to 0.229). In the Placebo group (n=16), delirium severity was associated with the number of instrumented vertebral levels (P=0.001) and with postoperative interleukin -8 and -10 concentrations (P=0.00008 and P=0.005, respectively) and these associations were not significantly modified by TXA. In the Placebo group, delirium severity was associated with S100B concentration (P=0.0009) and the strength of the association was decreased by TXA (P=0.002).

Conclusions

A potential 33% relative decrease in postoperative delirium incidence justifies an adequately powered clinical trial to determine if intraoperative TXA decreases delirium in adults undergoing lumbar fusion.

Suvorexant for Reduction of Delirium in Older Adults After Hospitalization: A Randomized Clinical Trial

Importance

Delirium is common among older hospitalized adults. In addition to presenting immediate management issues, delirium can increase the long-term risk of dementia, institutionalization, and mortality. Delirium is associated with disrupted sleep, and prior studies suggest that some specific sleep-promoting agents may reduce delirium.

Objective

To evaluate the orexin receptor antagonist suvorexant for reducing delirium in older adults at high risk for delirium after hospitalization.

Design, Setting, and Participants

This double-blind, placebo-controlled, phase 3 randomized clinical trial was conducted at 50 hospitals in Japan between October 22, 2020, and December 23, 2022. The study population included Japanese adults aged 65 to 90 years who were at high risk for delirium (mild cognitive impairment or mild dementia, history of delirium at prior hospitalization, or both) and had been hospitalized for acute disease or elective surgery. Data analysis was performed between January 23 and March 13, 2023.

Intervention

Participants were randomized 1:1 to suvorexant (15 mg) or placebo taken at bedtime for up to 7 days while in the hospital.

Main Outcomes and Measures

Delirium, the primary end point, was diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria while participants were hospitalized. The treatment difference in the proportion of participants with delirium was analyzed.

Results

This study included 203 participants: 101 were treated with suvorexant (mean [SD] age, 81.5 [4.5]; years; 52 men [51.5%] and 49 women [48.5%]) and 102 received placebo (mean [SD] age, 82.0 [4.9] years; 45 men [44.1%] and 57 women [55.9%]). There were 17 participants with delirium (16.8%) in the suvorexant group compared with 27 (26.5%) in the placebo group (difference, -8.7% [95% CI, -20.1% to 2.6%]; P = .13). Adverse events were similar between the 2 groups.

Conclusions and Relevance

In this randomized clinical trial of suvorexant in older adults at high risk for delirium after hospitalization, fewer participants taking suvorexant had delirium compared with placebo, but the difference was not statistically significant. Further studies are needed to determine whether suvorexant may be useful for reducing delirium, particularly delirium with a hyperactive component, in this population.

Trial Registration

ClinicalTrials.gov Identifier: NCT04571944.

Effects of an Integrated Geriatric-Orthopedic Co-management (InGerO) on the Treatment of Older Orthopedic Patients with Native and Periprosthetic Joint Infections

In view of our aging society, co-management with a geriatrician is becoming increasingly important. While such collaborations have been working successfully in trauma surgery for years, it is still unclear whether they are also helpful for non-trauma patients in orthopedics. The aim of this study was to investigate the effect of such a cooperation in orthopedic non-trauma patients with native and periprosthetic joint infections on the basis of five key areas.A retrospective observational study as a before and after comparison was used to compare routine data from patients with and without orthogeriatric co-management after nontraumatic surgery. Eligible patients for the study were 70 years and older, had a diagnosis of hip, knee, or shoulder infection, and had been hospitalized for at least 14 days. Co-management consisted of close follow-up by a geriatrician, Comprehensive Geriatric Assessment, and "complex early geriatric rehabilitation". The comparison group received therapy as usual, without a geriatrician and without "complex early geriatric rehabilitation". Special attention was paid to delirium, pain, mobility, postoperative complications, and renal function.Analysis was carried out with 59 patients "with" and 63 "without" geriatric co-management. In the co-management group, delirium was detected significantly more often (p < 0.001), significantly lower pain intensities were measured at the time of discharge (p < 0.001), transfer ability had clearly improved more (p = 0.04), and renal function was more frequently noted (p = 0.04). No significant differences were found with respect to principal diagnoses, surgical procedures performed, complication rates, pressure ulcer and delirium incidence, operative revisions, or length of inpatient stay.Orthogeriatric co-management in orthopedic patients with native and periprosthetic joint infections and nontraumatic surgery appears to have positive impacts on recognition and treatment of delirium, pain management, transfer performance, and attention to renal function. Further studies should follow in order to conclusively assess the value of such co-management in orthopedic nontraumatic surgery patients.

Effects of Chinese traditional five-element music intervention on postoperative delirium and sleep quality in elderly patients after non-cardiac surgery: a randomized controlled trial

BACKGROUND

Postoperative delirium (POD) is a common neurologic disorder among elderly patients after non-cardiac surgery, which leads to various negative outcomes. Sleep disorder is considered an important cause of POD. The objective of this study was to investigate whether the Chinese traditional five-element music intervention could reduce POD by improving sleep quality in elderly patients undergoing non-cardiac surgery.

METHODS

A total of 132 patients aged 65 to 90 years who underwent non-cardiac surgery were randomized to two groups: the intervention (n = 60) and the control group (n = 63). Patients in the intervention group were subjected to the Chinese traditional five-element music intervention during the perioperative, while patients in the control group had no music intervention. POD was evaluated using the Confusion Assessment Method (CAM) in the first 5 days after surgery. The Richards‒Campbell Sleep Questionnaire (RCSQ) was used to assess subjective sleep quality. The levels of nocturnal melatonin and cortisol in saliva were measured on the preoperative and the first 2 postoperative days.

RESULTS

The incidence of POD within 5 days was 27.0% in the control group and 11.7% in the intervention group. Preoperative PSQI and MMSE scores were associated with POD. The RCSQ scores on the first postoperative day were significantly decreased in the two groups compared to the preoperative day. Compared to the control group, the RCSQ scores showed a significant improvement in the intervention group on the first postoperative day. Compared to the control group, the level of saliva melatonin in the intervention group showed a significant increase on the first postoperative day. However, there was no statistical difference in cortisol levels between the two groups.

CONCLUSIONS

Chinese traditional five-element music intervention decreased the incidence of POD in elderly patients who underwent noncardiac surgery via improving sleep quality, which may be associated with increased levels of melatonin.

Development and validation of a new drug-focused predictive risk score for postoperative delirium in orthopaedic and trauma surgery patients

BACKGROUND

Postoperative delirium (POD) is the most common complication following surgery in elderly patients. During pharmacist-led medication reconciliation (PhMR), a predictive risk score considering delirium risk-increasing drugs and other available risk factors could help to identify risk patients.

METHODS

Orthopaedic and trauma surgery patients aged ≥ 18 years with PhMR were included in a retrospective observational single-centre study 03/2022-10/2022. The study cohort was randomly split into a development and a validation cohort (6:4 ratio). POD was assessed through the 4 A's test (4AT), delirium diagnosis, and chart review. Potential risk factors available at PhMR were tested via univariable analysis. Significant variables were added to a multivariable logistic regression model. Based on the regression coefficients, a risk score for POD including delirium risk-increasing drugs (DRD score) was established.

RESULTS

POD occurred in 42/328 (12.8%) and 30/218 (13.8%) patients in the development and validation cohorts, respectively. Of the seven evaluated risk factors, four were ultimately tested in a multivariable logistic regression model. The final DRD score included age (66-75 years, 2 points; > 75 years, 3 points), renal impairment (eGFR < 60 ml/min/1.73m2, 1 point), anticholinergic burden (ACB-score ≥ 3, 1 point), and delirium risk-increasing drugs (n ≥ 2; 2 points). Patients with ≥ 4 points were classified as having a high risk for POD. The areas under the receiver operating characteristic curve of the risk score model were 0.89 and 0.81 for the development and the validation cohorts, respectively.

CONCLUSION

The DRD score is a predictive risk score assessable during PhMR and can identify patients at risk for POD. Specific preventive measures concerning drug therapy safety and non-pharmacological actions should be implemented for identified risk patients.

Assessment and report of individual symptoms in studies of delirium in postoperative populations: a systematic review

OBJECTIVES

Delirium is most often reported as present or absent. Patients with symptoms falling short of the diagnostic criteria for delirium fall into 'no delirium' or 'control' groups. This binary classification neglects individual symptoms and may be hindering identification of the pathophysiology underlying delirium. This systematic review investigates which individual symptoms of delirium are reported by studies of postoperative delirium in adults.

METHODS

Medline, EMBASE and Web of Science databases were searched on 03 June 2021 and 06 April 2023. Two reviewers independently examined titles and abstracts. Each paper was screened in duplicate and conflicting decisions settled by consensus discussion. Data were extracted, qualitatively synthesised and narratively reported. All included studies were quality assessed.

RESULTS

These searches yielded 4,367 results. After title and abstract screening, 694 full-text studies were reviewed, and 62 deemed eligible for inclusion. This review details 11,377 patients including 2,049 patients with delirium. In total, 78 differently described delirium symptoms were reported. The most reported symptoms were inattention (N = 29), disorientation (N = 27), psychomotor agitation/retardation (N = 22), hallucination (N = 22) and memory impairment (N = 18). Notably, psychomotor agitation and hallucinations are not listed in the current Diagnostic and Statistical Manual for Mental Disorders-5-Text Revision delirium definition.

CONCLUSIONS

The 78 symptoms reported in this systematic review cover domains of attention, awareness, disorientation and other cognitive changes. There is a lack of standardisation of terms, and many recorded symptoms are synonyms of each other. This systematic review provides a library of individual delirium symptoms, which may be used to inform future reporting.

The Efficacy of Ramelteon to Prevent Postoperative Delirium After General Anesthesia in the Elderly: A Double-Blind, Randomized, Placebo-Controlled Trial

OBJECTIVE

Postoperative delirium is common and serious in elderly patients. Several drugs have been proposed as potential prophylactic agents for postoperative delirium. Studies on melatonin receptor agonists showed heterogeneity in age, cognitive function, anesthesia, surgery, interventions, methodologies for assessing outcomes, and results. Our objective was to examine the effect of ramelteon to prevent postoperative delirium in elderly patients, including those with dementia.

DESIGN

A stratified, double-blind, randomized, placebo-controlled trial (UMIN000028436, jRCTs031180054).

SETTING

Tertiary medical center.

PARTICIPANTS

Patients aged older than or equal to 65 years undergoing elective surgery under general anesthesia.

INTERVENTION

Ramelteon (8 mg orally) or placebo (lactose) for six nights (the preoperative night and five consecutive nights from postoperative day 1 to 5) at around 9 P.M.

MEASUREMENTS

Patients were screened for postoperative delirium using the Confusion Assessment Method for the Intensive Care Unit twice daily until the sixth postoperative day. Patients with positive results were referred to a consultant psychiatrist to establish the diagnosis of delirium.

RESULTS

A total of 108 patients were randomly assigned to receive ramelteon (n = 55) or placebo (n = 53). Most of the patients' characteristics were reasonably well-balanced between the two groups. The stratified log-rank test showed no significant difference in preventing postoperative delirium between ramelteon and placebo (χ2 = 0.30, degrees of freedom = 1, p = 0.60). The Cox proportional hazard ratio for ramelteon compared to placebo was 1.40 (95% confidence interval: 0.40-4.85, χ2 for likelihood ratio test = 0.29, degrees of freedom = 1, p = 0.60).

CONCLUSION

There was no significant difference in the incidence of postoperative delirium between ramelteon and placebo after general anesthesia in elderly patients.

Development of postoperative delirium prediction models in patients undergoing cardiovascular surgery using machine learning algorithms

Associations between delirium and postoperative adverse events in cardiovascular surgery have been reported and the preoperative identification of high-risk patients of delirium is needed to implement focused interventions. We aimed to develop and validate machine learning models to predict post-cardiovascular surgery delirium. Patients aged ≥ 40 years who underwent cardiovascular surgery at a single hospital were prospectively enrolled. Preoperative and intraoperative factors were assessed. Each patient was evaluated for postoperative delirium 7 days after surgery. We developed machine learning models using the Bernoulli naive Bayes, Support vector machine, Random forest, Extra-trees, and XGBoost algorithms. Stratified fivefold cross-validation was performed for each developed model. Of the 87 patients, 24 (27.6%) developed postoperative delirium. Age, use of psychotropic drugs, cognitive function (Mini-Cog < 4), index of activities of daily living (Barthel Index < 100), history of stroke or cerebral hemorrhage, and eGFR (estimated glomerular filtration rate) < 60 were selected to develop delirium prediction models. The Extra-trees model had the best area under the receiver operating characteristic curve (0.76 [standard deviation 0.11]; sensitivity: 0.63; specificity: 0.78). XGBoost showed the highest sensitivity (AUROC, 0.75 [0.07]; sensitivity: 0.67; specificity: 0.79). Machine learning algorithms could predict post-cardiovascular delirium using preoperative data.Trial registration: UMIN-CTR (ID; UMIN000049390).

Occurrence and predictors of delirium in critically ill older patients: a prospective cohort study

Objectives

This study aims to analyze the occurrence of delirium in critically ill older patients and to identify predictors of delirium.

Methods

This prospective study included critically ill older patients admitted into level II units of Intensive Care Medicine Department of a University Hospital. Patients with Glasgow Coma Scale score ≤11, traumatic brain injury, terminal disease, history of psychosis, blindness/deafness, or inability to understanding/speaking Portuguese were excluded. The Confusion Assessment Method-Short Form (CAM-4) was used to assess the presence of delirium.

Results

The final sample (n = 105) had a median age of 80 years, most being female (56.2%), widowed (49.5%), and with complete primary education (53%). Through CAM-4, 36.2% of the patients had delirium. The delirium group was more likely to have previous cognitive decline (48.6% vs 19.6%, P = .04) and severe dependency in instrumental activities of daily living (34.3% vs 14.8%, P = .032), comparing with patients without delirium. The final multiple logistic regression model explained that patients with previous cognitive decline presented a higher risk for delirium (odds ratio: 4.663, 95% confidence Interval: 1.055-20.599, P = .042).

Conclusions

These findings corroborate previous studies, showing that cognitive decline is an independent predictor for delirium in older patients. This study is an important contribution for the knowledge regarding the predictors of delirium. The recognition of these factors will help to identify patients who are at high risk for this syndrome and implement early screening and prevention strategies. However, further studies with larger samples, recruited from other clinical settings as well as analyzing other potential factors for delirium, will be needed.

The impact of preoperative malnutrition on postoperative delirium: a systematic review and meta-analysis

BACKGROUND

Postoperative delirium (POD) is a common postoperative complication, characterized by disturbance of attention, perception, and consciousness within 1 week after surgery, and linked to cognitive decline, increased mortality, and other serious surgical outcomes. Early identification and treatment of risk factors for POD could reduce the occurrence of delirium and the related poor outcomes. Malnutrition as a possible precipitating factor, defined as the poor anthropometric, functional, and clinical outcomes of nutrient deficiency, has been investigated. However, the evidence is controversial. The goal of this systematic review and meta-analysis was to comprehensively assess the correlation between preoperative malnutrition and POD.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were used to search prospective cohort articles that explored the correlation between preoperative malnutrition and POD from inception until September 30, 2022. Two researchers independently conducted the literature selection and data extraction. The quality of the literature was evaluated according to the Newcastle-Ottawa scale (NOS). Odds ratios (ORs) and 95% confidence intervals (CIs) for POD associated with malnutrition relative to normal nutritional status were calculated.

RESULTS

Seven prospective cohort studies qualified for the meta-analysis, which included 2701 patients. The pooled prevalence of preoperative malnutrition was 15.1% (408/2701), and POD occurred in 428 patients (15.8%). The NOS score was above 7 points in all 7 studies. Our results demonstrated that the pooled OR for malnutrition and POD was 2.32 (95% CI 1.62-3.32) based on a random-effects model. Our subgroup analysis suggested that the relationship between malnutrition and POD was significant in adults following noncardiac surgery (OR = 3.04, 95% CI, 1.99-4.62, P < 0.001), while there was no statistical significance in adults following cardiac surgery (OR = 1.76, 95% CI, 0.96-3.22, P = 0.07). Additionally, in the subgroup analysis based on different malnutrition assessment tools (MNA-SF versus others), a significant association was found in the MNA-SF group (OR = 3.04, 95% CI, 1.99-4.62, P < 0.001), but not in the others group (OR = 1.76, 95% CI, 0.96-3.22, P = 0.07). Other subgroup analyses showed that this association was not significantly affected by evaluation instruments for POD, location of the study, or quality of the article (all P < 0.05).

CONCLUSIONS

Based on the currently available evidence, our results suggested that preoperative malnutrition was independently associated with POD in adult surgical patients.

Perioperative Factors Associated With Postoperative Delirium in Patients Undergoing Noncardiac Surgery: An Individual Patient Data Meta-Analysis

Importance

Postoperative delirium (POD) is a common and serious complication after surgery. Various predisposing factors are associated with POD, but their magnitude and importance using an individual patient data (IPD) meta-analysis have not been assessed.

Objective

To identify perioperative factors associated with POD and assess their relative prognostic value among adults undergoing noncardiac surgery.

Data Sources

MEDLINE, EMBASE, and CINAHL from inception to May 2020.

Study Selection

Studies were included that (1) enrolled adult patients undergoing noncardiac surgery, (2) assessed perioperative risk factors for POD, and (3) measured the incidence of delirium (measured using a validated approach). Data were analyzed in 2020.

Data Extraction and Synthesis

Individual patient data were pooled from 21 studies and 1-stage meta-analysis was performed using multilevel mixed-effects logistic regression after a multivariable imputation via chained equations model to impute missing data.

Main Outcomes and Measures

The end point of interest was POD diagnosed up to 10 days after a procedure. A wide range of perioperative risk factors was considered as potentially associated with POD.

Results

A total of 192 studies met the eligibility criteria, and IPD were acquired from 21 studies that enrolled 8382 patients. Almost 1 in 5 patients developed POD (18%), and an increased risk of POD was associated with American Society of Anesthesiologists (ASA) status 4 (odds ratio [OR], 2.43; 95% CI, 1.42-4.14), older age (OR for 65-85 years, 2.67; 95% CI, 2.16-3.29; OR for >85 years, 6.24; 95% CI, 4.65-8.37), low body mass index (OR for body mass index <18.5, 2.25; 95% CI, 1.64-3.09), history of delirium (OR, 3.9; 95% CI, 2.69-5.66), preoperative cognitive impairment (OR, 3.99; 95% CI, 2.94-5.43), and preoperative C-reactive protein levels (OR for 5-10 mg/dL, 2.35; 95% CI, 1.59-3.50; OR for >10 mg/dL, 3.56; 95% CI, 2.46-5.17). Completing a college degree or higher was associated with a decreased likelihood of developing POD (OR 0.45; 95% CI, 0.28-0.72).

Conclusions and Relevance

In this systematic review and meta-analysis of individual patient data, several important factors associated with POD were found that may help identify patients at high risk and may have utility in clinical practice to inform patients and caregivers about the expected risk of developing delirium after surgery. Future studies should explore strategies to reduce delirium after surgery.

Association of cervical atherosclerosis on Doppler ultrasonography and postoperative delirium in patients undergoing spinal surgery: a single-center, retrospective, observational study

PURPOSE

This study aimed to evaluate the association between cervical atherosclerosis on Doppler ultrasonography and postoperative delirium (POD) in patients undergoing spinal surgery.

METHODS

In this retrospective observational study using prospectively collected data, 295 consecutive patients aged > 50 years underwent spine surgery at a single institution between March 2015 and February 2021. Cervical atherosclerosis was defined as the intima-media thickness (IMT) of the common carotid artery (CCA) being ≥ 1.1 mm on pulsed-wave Doppler ultrasonography. Univariate and multivariate logistic regression analyses were performed with the prevalence of postoperative delirium as a dependent variable. Age, sex, body mass index, medical history, American Society of Anesthesiologists Physical Status (ASA-PS), CHADS2 score (an assessment score for stroke), instrumentation, duration of surgery, blood loss, and cervical arteriosclerosis were the independent variables.

RESULTS

Twenty-seven patients of 295 (9.2%) developed delirium postoperatively. Forty-one (13.9%) of the 295 patients had cervical atherosclerosis. Their univariate analyses showed that age (P = 0.001), hypertension (P = 0.016), cancer (P = 0.046), antiplatelet agent use (P < 0.001), ASA-PS ≥ 3 (P < 0.001), CHADS2 score (P < 0.001), cervical atherosclerosis (P = 0.008), and right CCA-IMT (P = 0.007) were significantly associated with POD. However, multivariate logistic regression analyses showed older age (odds ratio [OR], 1.109; 95% confidence interval [CI] 1.035-1.188; P = 0.03) and antiplatelet agent use (OR, 3.472; 95% CI 1.221-9.870; P = 0.020) to be significantly associated with POD.

CONCLUSIONS

There was a significant association between POD and the prevalence of cervical atherosclerosis using the univariate logistic regression analysis. Furthermore, multivariate logistic regression analyses showed that older age and antiplatelet agent use were independently associated with POD.

Preoperative assessment of postoperative delirium: a cross-sectional study of patients and anesthesiologists in Canada

PURPOSE

We sought to evaluate 1) patient- and anesthesiologist-reported rates of postoperative delirium (POD) risk discussion during preoperative meetings, 2) patients' and anesthesiologists' ratings of the importance of POD, and 3) predictors of patient-reported discussion of POD risk during preoperative meetings.

METHODS

In this multicentre two-part cross-sectional survey study, patients ≥ 65 yr scheduled to undergo elective noncardiac surgery completed a five-minute survey after preoperative anesthesia consultation. Patients were asked about their perception of POD importance, and whether they discussed or were assessed for POD risk. Anesthesiologists were surveyed using self-administered surveys circulated via institutional email lists. Anesthesiologists were asked about the frequency of POD risk assessment and discussion in older adults, tools used, and perception of POD-screening barriers.

RESULTS

Four hundred and twelve (of 510 approached) patients (50% male; mean age, 73 yr) and 267 anesthesiologists (of 1,205 invited via e-mail) participated in this study conducted in five Canadian hospitals. Postoperative delirium screening and discussion was reported by 88/412 (22%) patients and 229/267 (86%) anesthesiologists. Postoperative delirium was rated as "somewhat-extremely" important by 64% of patients. A previous history of delirium, higher education, the number of daily medications, and longer surgical duration were associated with POD discussion. On average, anesthesiologists rated the importance of POD at 8/10, and 42% ranked "patient risk factors" as the top reason prompting discussion.

CONCLUSION

The combined evaluation of patients' and anesthesiologists' perspectives provides valuable information on preoperative POD screening and risk assessment, and highlights areas for improvement in the current practice. Most factors we identified to be associated with higher odds of POD discussion are recognized risk factors of POD.

Assessing and managing frailty in emergency laparotomy: a WSES position paper

Many countries are facing an aging population. As people live longer, surgeons face the prospect of operating on increasingly older patients. Traditional teaching is that with older age, these patients face an increased risk of mortality and morbidity, even to a level deemed too prohibitive for surgery. However, this is not always true. An active 90-year-old patient can be much fitter than an overweight, sedentary 65-year-old patient with comorbidities. Recent literature shows that frailty-an age-related cumulative decline in multiple physiological systems, is therefore a better predictor of mortality and morbidity than chronological age alone. Despite recognition of frailty as an important tool in identifying vulnerable surgical patients, many surgeons still shun objective tools. The aim of this position paper was to perform a review of the existing literature and to provide recommendations on emergency laparotomy and in frail patients. This position paper was reviewed by an international expert panel composed of 37 experts who were asked to critically revise the manuscript and position statements. The position paper was conducted according to the WSES methodology. We shall present the derived statements upon which a consensus was reached, specifying the quality of the supporting evidence and suggesting future research directions.

Frailty Assessment and Prehabilitation as Part of a PeRioperative Evaluation and Planning (PREP) Program for Patients Undergoing Colorectal Surgery

Frailty assessment and prehabilitation can be incrementally implemented in a multidisciplinary, multiphase pathway to improve patient care. To start, modifications can be made to a surgeon's practice with existing resources while adapting standard pathways for frail patients. Frailty screening can identify patients in need of additional assessment and optimization. Personalized utilization of frailty data for optimization through prehabilitation can improve postoperative outcomes and identify patients who would benefit from adapted care. Additional utilization of the multidisciplinary team can lead to improved outcomes and a strong business case to add additional members of the team.

Risk factors and effect of postoperative delirium on adverse surgical outcomes in older adults after elective abdominal cancer surgery in Taiwan

BACKGROUND

Postoperative delirium (POD) is a common complication in older adults, with unknown epidemiology and effects on surgical outcomes in Asian geriatric cancer patients. This study evaluated incidence, risk factors, and association between adverse surgical outcomes and POD after intra-abdominal cancer surgery in Taiwan.

METHODS

Overall, 345 patients aged ≥65 years who underwent elective abdominal cancer surgery at a medical center in Taiwan were prospectively enrolled. Delirium was assessed daily using the Confusion Assessment Method. Univariate and multivariate logistic regression analyses investigated risk factors for POD occurrence and estimated the association with adverse surgical outcomes.

RESULTS

POD occurred in 19 (5.5%) of the 345 patients. Age ≥73 years, Charlson comorbidity index ≥3, and operative time >428 min were independent predictors for POD occurrence. Patients presenting with one, two, and three risk factors had 4.1-fold (95% confidence interval [CI], 0.4-35.8, p = 0.20), 17.4-fold (95% CI, 2.2-138, p = 0.007), and 30.8-fold likelihood (95% CI, 2.9-321, p = 0.004) for POD occurrence, respectively. Patients with POD had a higher probability of prolonged hospital stay (adjusted odds ratio [OR] 2.8; 95% CI, 1.0-8.1; p = 0.037), intensive care stay (adjusted OR: 3.9; 95% CI, 1.5-10.5; p = 0.008), 30-day readmission (adjusted OR 3.1; 95% CI, 1.1-9.7; p = 0.039), and 90-day postoperative death (adjusted OR: 4.2; 95% CI, 1.0-17.7; p = 0.041).

CONCLUSION

POD occurrence was significantly associated with adverse surgical outcomes in geriatric patients undergoing elective abdominal cancer surgery, highlighting the importance of early POD identification in geriatric patients to improve postoperative care quality.

Contribution of intraoperative electroencephalogram suppression to frailty-associated postoperative delirium: mediation analysis of a prospective surgical cohort

BACKGROUND

Frailty is a risk factor for postoperative delirium (POD), and has led to preoperative interventions that have reduced, but not eliminated, the risk. We hypothesised that EEG suppression, another risk factor for POD, mediates some of the frailty risk for POD.

METHODS

A prospective cohort study enrolled patients aged 65 yr or older, scheduled for noncardiac surgery under total intravenous anaesthesia. Frailty was assessed using the FRAIL scale. Cumulative duration of EEG suppression, defined as an amplitude between -5 and 5 μV for >0.5 s during anaesthesia, was measured. POD was diagnosed by either confusion assessment method (CAM), CAM-ICU, or medical records. The severity of POD was assessed using the Delirium Rating Scale - Revised-98 (DRS). Mediation analysis was used to estimate the relationships between frailty, EEG suppression, and severity of POD.

RESULTS

Among 252 enrolled patients, 51 were robust, 129 were prefrail, and 72 were frail. Patients classified as frail had higher duration of EEG suppression than either the robust (19 vs 0.57 s, P<0.001) or prefrail groups (19 vs 3.22 s, P<0.001). Peak delirium score was higher in the frail group than either the robust (17 vs 15, P<0.001) or prefrail groups (17 vs 16, P=0.007). EEG suppression time mediated 24.2% of the frailty-DRS scores association.

CONCLUSION

EEG suppression time mediated a statistically significant portion of the frailty-POD association in older noncardiac surgery patients. Trials directed at reducing EEG suppression time could result in intraoperative interventions to reduce POD in frail patients.

CLINICAL TRIAL REGISTRATION

ChiCTR2000041092 (Chinese Clinical Trial Registry).

Perioperative risk factors associated with increased incidence of postoperative delirium: systematic review, meta-analysis, and Grading of Recommendations Assessment, Development, and Evaluation system report of clinical literature

BACKGROUND

Systematic reviews to date have neglected to exclusively include studies using a validated diagnostic scale for postoperative delirium and monitoring patients for more than 24 h. Evidence on current risk factors is evolving with significantly heterogeneous study designs, inconsistent reporting of results, and a lack of adjustment for bias.

METHODS

This systematic review and meta-analysis aimed to identify risk factors for postoperative delirium in an adult patient population. Study designs suitable for this review included full-text articles, RCTs, observational studies, cohort studies, and case-control studies. Extracted variables from the 169 (7.4%) selected studies were included in qualitative synthesis, quantitative synthesis, and a postoperative delirium checklist. The 16 variables included in the checklist were selected based on consistency, direction of effect, number of studies, and clinical utility as a reference for future studies.

RESULTS

A total of 576 variables were extracted, but only six were eligible for meta-analysis. Age (mean difference [MD]=4.94; 95% confidence interval [CI], 2.93-6.94; P<0.001), American Society of Anesthesiologists physical status >2 (odds ratio [OR]=2.27; 95% CI, 1.47-3.52; P<0.001), Charlson Comorbidity Index ≥2 (OR=1.9; 95% CI, 1.11-3.25; P=0.0202), and Mini-Mental State Examination (MD=-1.94; 95% CI, -3.6 to -0.27; P=0.0224) were statistically significant.

CONCLUSIONS

Risk factors can assist in clinical decision-making and identification of high-risk patients. Literature analysis identified inconsistent methodology, leading to challenges in interpretation. A standardised format and evidence-based approach should guide future studies.

Postoperative delirium in older patients after undergoing pelvic organ prolapse surgery

INTRODUCTION AND HYPOTHESIS

To determine the 7-day incidence and risk factors of postoperative delirium (POD) occurring after prolapse surgery in women aged ≥60 years.

METHODS

A prospective study of women ≥60 years undergoing prolapse surgery at a large academic center. The primary outcome is positive Confusion Assessment Method delirium screen administered in person or by telephone at the time of hospital discharge and postoperative days 1, 3, 5, and 7.

RESULTS

This analysis included 165 patients, mean ± SD age of 72.5 ± 6.1 years, with median (IQR) years of education of 13 (12-16), and baseline Modified Mini-Mental Status (3MS) Exam score of 95 (92-98). Prolapse repair type was vaginal for 70% (n=115) and laparoscopic for 30% (n=50) of patients; most under general anesthesia, 151 (92.1%). The incidence of positive delirium screen during the first week after surgery was 12.1% (n=20). Most of these participants screened positive on postoperative day 0, 8.4% (n=14). In univariate analyses, a positive screen was associated with older age and fewer education years, lower 3MS exam score, greater baseline geriatric depression scale score, and greater frailty score. Lower 3MS score was the only variable that remained significant in the final model (adjusted odds ratio 0.84, 95% CI 0.75-0.95).

CONCLUSIONS

One in 12 women ≥60 years deemed eligible for discharge on the day of prolapse surgery screens positive for delirium. The 7-day POD incidence is comparable to other elective non-cardiac surgery cohorts. Given the increasing trend toward same day discharge after major prolapse surgery, more research is needed to determine the impact of universal delirium screening as part of discharge assessments.

Decision making in frail patients at risk of postoperative delirium: A case study and literature review

Preoperative frailty is strongly associated with risks of postoperative delirium. However, gaps exist in targeted recommendations for clinical decision making related to surgical interventions in frail older patients. A case study is presented involving a frail 74-year-old referred to the palliative care team for assistance with clinical decision making and in weighing risks and benefits of a surgical intervention. A literature review on the quantification of postoperative delirium risk and how this information might inform medical decision making in frail surgical patients did not identify clear clinical guidelines. In the absence of practice guidelines, the Patient Priorities Care model is proposed as a framework to help providers working with patients and caregivers facing complex medical decisions to better align interventions with patient values.

Identifying barriers and facilitators to routine preoperative frailty assessment: a qualitative interview study

PURPOSE

Preoperative frailty assessment is recommended by multiple practice guidelines and may improve outcomes, but it is not routinely performed. The barriers and facilitators of routine preoperative frailty assessment have not been formally assessed. Our objective was to perform a theory-guided evaluation of barriers and facilitators to preoperative frailty assessment.

METHODS

This was a research ethics board-approved qualitative study involving physicians who perform preoperative assessment (consultant and resident anesthesiologists and consultant surgeons). Semistructured interviews were conducted by a trained research assistant informed by the Theoretical Domains Framework to identify barriers and facilitators to frailty assessment. Interview transcripts were independently coded by two research assistants to identify specific beliefs relevant to each theoretical domain.

RESULTS

We interviewed 28 clinicians (nine consultant anesthesiologists, nine consultant surgeons, and ten anesthesiology residents). Six domains (Knowledge [100%], Social Influences [96%], Social Professional Role and Identity [96%], Beliefs about Capabilities [93%], Goals [93%], and Intentions [93%]) were identified by > 90% of respondents. The most common barriers identified were prioritization of other aspects of assessment (e.g., cardio/respiratory) and a lack of awareness of evidence and guidelines supporting frailty assessment. The most common facilitators were a high degree of familiarity with frailty, recognition of the importance of frailty assessment, and strong intentions to perform frailty assessment.

CONCLUSION

Barriers and facilitators to preoperative frailty assessment are multidimensional, but generally consistent across different types of perioperative physicians. Knowledge of barriers and facilitators can guide development of evidence-based strategies to increase frailty assessment.

The influence of orthopedic surgery on the incidence of post-operative delirium in geriatric patients: results of a prospective observational study

Background

Postoperative delirium (PD) is a major concern in geriatric patients undergoing orthopedic surgery. This prospective observational study aims to examine the incidence of PD, to identify intervention-specific risk factors and to investigate the influence of orthopedic surgery on delirium.

Methods

From 2019 to 2020, 132 patients ≥70 years of age with endoprosthetic (Group E) or spinal surgery (Group S) were included. Upon admission, the ISAR score, the Nursing Delirium Screening Scale, potential risk factors, the ASA score, duration of surgery, type of anesthesia, blood loss, and hemoglobin drop were recorded. For risk factor analysis patients were grouped into Group D (delirium) and Group ND (no delirium). Primary endpoint was the occurrence of PD.

Results

Of 132 patients, 50 were included in Group E and 82 in Group S. Mean age and ISAR score were not significantly different between groups. Delirium rate in Group E and S was 12% vs. 18% (p = 0.3). Differences could be observed between Group D and ND in duration of surgery (173 min vs. 112 min, p = 0.02), postoperative hemoglobin drop (3.2 g/dl vs. 2.3 g/dl; p = 0.026), history of PD (23% vs. 11%, p = 0.039) and use of isoflurane (6 vs. 2). Type of surgery was not an independent risk factor (p = 0.26).

Conclusion

Specific type of orthopedic surgery is not an independent risk factor for PD. Prevention of PD should focus on duration of surgery and blood loss, particularly in patients with a history of PD. A possible delirogenic potential of isoflurane should be further studied.

Risk factors for postoperative delirium in elderly urological patients: A meta-analysis

BACKGROUND

Avoiding postoperative delirium (POD) can have a significant detrimental effect on the rehabilitation and prognosis of elderly urological patients. It is necessary to explore the risk factors associated with POD in elderly urology to provide a basis for clinical recognition of delirium.

METHODS

For relevant studies, we comprehensively searched Embase, MEDLINE, Ovid, PubMed, Scopus, The Cochrane Library, and Web of Science. The search deadline was September 2021.

RESULTS

We identified 2046 studies, 8 of which were included in the ultimate analysis. A total of 8 articles, including 356 cases in the delirium group and 1813 cases in the non-delirium group, were included in the relevant literature. The 2 groups mentioned above differed significantly in the following factors: history of delirium (odds ratio [OR] = 6.98, 95% confidence interval [CI]: 1.63-29.86, P = .009); Preoperative use of psychotropic drugs (OR = 1.97, 95% CI: 1.11-3.52, P = .02); age (OR = 3.10, 95% CI: 2.08-4.12, P < .0001). The meta-analysis demonstrated that smoking, alcohol consumption, gender (male), mode of anesthesia (general anesthesia) and being unmarried did not have a significant effect on POD in elderly urological patients.

CONCLUSION

The risk factors for POD in elderly urological patients include history of delirium, preoperative use of psychotropic drugs, and age. The present study provides guidance for taking targeted preventive measures to reduce risks.

Quality of Life in Older Adults After Major Cancer Surgery: The GOSAFE International Study

BACKGROUND

Accurate quality of life (QoL) data and functional results after cancer surgery are lacking for older patients. The international, multicenter Geriatric Oncology Surgical Assessment and Functional rEcovery after Surgery (GOSAFE) Study compares QoL before and after surgery and identifies predictors of decline in QoL.

METHODS

GOSAFE prospectively collected data before and after major elective cancer surgery on older adults (≥70 years). Frailty assessment was performed and postoperative outcomes recorded (30, 90, and 180 days postoperatively) together with QoL data by means of the three-level version of the EuroQol five-dimensional questionnaire (EQ-5D-3L), including 2 components: an index (range = 0-1) generated by 5 domains (mobility, self-care, ability to perform the usual activities, pain or discomfort, anxiety or depression) and a visual analog scale.

RESULTS

Data from 26 centers were collected (February 2017-March 2019). Complete data were available for 942/1005 consecutive patients (94.0%): 492 male (52.2%), median age 78 years (range = 70-95 years), and primary tumor was colorectal in 67.8%. A total 61.2% of all surgeries were via a minimally invasive approach. The 30-, 90-, and 180-day mortality was 3.7%, 6.3%, and 9%, respectively. At 30 and 180 days, postoperative morbidity was 39.2% and 52.4%, respectively, and Clavien-Dindo III-IV complications were 13.5% and 18.7%, respectively. The mean EQ-5D-3L index was similar before vs 3 months but improved at 6 months (0.79 vs 0.82; P < .001). Domains showing improvement were pain and anxiety or depression. A Flemish Triage Risk Screening Tool score greater than or equal to 2 (odds ratio [OR] = 1.58, 95% confidence interval [CI] = 1.13 to 2.21, P = .007), palliative surgery (OR = 2.14, 95% CI = 1.01 to 4.52, P = .046), postoperative complications (OR = 1.95, 95% CI = 1.19 to 3.18, P = .007) correlated with worsening QoL.

CONCLUSIONS

GOSAFE shows that older adults' preoperative QoL is preserved 3 months after cancer surgery, independent of their age. Frailty screening tools, patient-reported outcomes, and goals-of-care discussions can guide decisions to pursue surgery and direct patients' expectations.

A machine-learning model to predict postoperative delirium following knee arthroplasty using electronic health records

BACKGROUND

Postoperative delirium is a challenging complication due to its adverse outcome such as long hospital stay. The aims of this study were: 1) to identify preoperative risk factors of postoperative delirium following knee arthroplasty, and 2) to develop a machine-learning prediction model.

METHOD

A total of 3,980 patients from two hospitals were included in this study. The model was developed and trained with 1,931 patients from one hospital and externally validated with 2,049 patients from another hospital. Twenty preoperative variables were collected using electronic hospital records. Feature selection was conducted using the sequential feature selection (SFS). Extreme Gradient Boosting algorithm (XGBoost) model as a machine-learning classifier was applied to predict delirium. A tenfold-stratified area under the curve (AUC) served as the metric for variable selection and internal validation.

RESULTS

The incidence rate of delirium was 4.9% (n = 196). The following seven key predictors of postoperative delirium were selected: age, serum albumin, number of hypnotics and sedatives drugs taken preoperatively, total number of drugs (any kinds of oral medication) taken preoperatively, neurologic disorders, depression, and fall-down risk (all p < 0.05). The predictive performance of our model was good for the developmental cohort (AUC: 0.80, 95% CI: 0.77-0.84). It was also good for the external validation cohort (AUC: 0.82, 95% CI: 0.80-0.83). Our model can be accessed at https://safetka.connecteve.com .

CONCLUSIONS

A web-based predictive model for delirium after knee arthroplasty was developed using a machine-learning algorithm featuring seven preoperative variables. This model can be used only with information that can be obtained from pre-operative electronic hospital records. Thus, this model could be used to predict delirium before surgery and may assist physician's effort on delirium prevention.

Intraoperative use of low-dose dexmedetomidine for the prevention of emergence agitation following general anaesthesia in elderly patients: a randomized controlled trial

OBJECTIVE

To clarify the effect of an intraoperative low-dose dexmedetomidine infusion on emergence agitation following general anaesthesia in elderly patients.

METHODS

Eighty elderly patients (> 64-years-old) following elective general anaesthesia for radical cancer surgeries were randomly allocated into two groups (n = 40 each): the dexmedetomidine group (Group D) and the normal saline group (Group C). Anaesthesia was maintained with continuous intravenous infusion of dexmedetomidine at - 0.2 µg kg^-1 h^-1 in Group D, and an equal volume of normal saline (0.5 ml kg^-1 h^-1) was given in Group C. All patients were observed for 30 min in the post-anaesthesia care unit (PACU), AFPS and NRS were recorded every 2 min, and the total doses of nalbuphine and fentanyl were calculated in the PACU. MAP and HR were recorded at the time of 10 min (T1), 20 min (T2), 30 min (T3) after dexmedetomidine or saline pumping, and before extubation (T4), immediately after extubation (T5), and 5 min after extubation (T6). We also documented some durations, including anaesthesia duration (D1), surgery duration (D2), duration from the end of surgery to extubation (D3), and emergence agitation duration (D4).

RESULTS

The MAP in Group C was significantly higher than that in Group D (P < 0.05), and there were no significant changes between the two groups in HR and MAP within each time point and D1, D2, D3, and D4. The incidence of agitation, NRS score and total dose of nalbuphine and fentanyl were all lower in Group D than in Group C (P < 0.05).

CONCLUSION

An intraoperative low-dose dexmedetomidine continuous infusion can reduce emergence agitation following general anaesthesia in elderly patients (> 64-years-old), remain stable in terms of haemodynamics, and not lead to delays in anaesthesia recovery time and extubation time.

Outcomes of a Delirium Prevention Program in Older Persons After Elective Surgery: A Stepped-Wedge Cluster Randomized Clinical Trial

Importance

Delirium significantly worsens elective surgery outcomes and costs. Delirium risk is highest in elderly populations, whose surgical health care resource consumption (50%) exceeds their demographic proportion (15% to 18%) in high-resource countries. Effective nonpharmacologic delirium prevention could safely improve care in these vulnerable patients, but data from procedure-specific studies are insufficiently compelling to drive changes in practice. Delirium prevention approaches applicable to different surgical settings remain unexplored.

Objective

To examine whether a multifaceted prevention intervention is effective in reducing postoperative delirium incidence and prevalence after various major surgical procedures.

Design, Setting, and Participants

This stepped-wedge cluster randomized trial recruited 1470 patients 70 years and older undergoing elective orthopedic, general, or cardiac surgery from November 2017 to April 2019 from 5 German tertiary medical centers. Data were analyzed from December 2019 to July 2021.

Interventions

First, structured delirium education was provided to clinical caregivers at each site. Then, the study delirium prevention team assessed patient delirium risk factors and symptoms daily. Prevention was tailored to individual patient needs and could include: cognitive, motor, and sensory stimulation; meal companionship; accompaniment during diagnostic procedures; stress relaxation; and sleep promotion.

Main Outcomes and Measures

Postoperative delirium incidence and duration.

Results

Of 1470 included patients, 763 (51.9%) were male, and the median (IQR) age was 77 (74-81) years. Overall, the intervention reduced postoperative delirium incidence (odds ratio, 0.87; 95% CI, 0.77-0.98; P = .02) and percentage of days with delirium (intervention, 5.3%; control, 6.9%; P = .03). The effect was significant in patients undergoing orthopedic or abdominal surgery (odds ratio, 0.59; 95% CI, 0.35-0.99; P = .047) but not cardiac surgery (odds ratio, 1.18; 95% CI, 0.70-1.99; P = .54).

Conclusions and Relevance

This multifaceted multidisciplinary prevention intervention reduced postoperative delirium occurrence and days with delirium in older patients undergoing different elective surgical procedures but not cardiac procedures. These results suggest implementing this delirium prevention program will improve care and outcomes in older patients undergoing elective general and orthopedic procedures.

Challenges in Geriatric Oncology-A Surgeon's Perspective

As our global population ages, we will see more cancer diagnoses in older adults. Surgery is an important treatment modality for solid tumours, forming the majority of all cancers. However, the management of older adults with cancer can be more complex compared to their younger counterparts. This narrative review will outline the current challenges facing older adults with cancer and potential solutions. The challenges facing older adults with cancer are complex and include lack of high-level clinical trials targeting older adults and selection of the right patient for surgery. This may be standard surgical treatment, minimally invasive surgery or alternative therapies (no surgery) which can be local or systemic. The next challenge is to identify the individual patient's vulnerabilities to allow them to be maximally optimised for treatment. Prehabilitation has been shown to be of benefit in some cancer settings but uniform guidance across all surgical specialties is required. Greater awareness of geriatric conditions amongst surgical oncologists and integration of geriatric assessment into a surgical clinic are potential solutions. Enhanced recovery programmes tailored to older adults could reduce postoperative functional decline. Ultimately, the greatest challenge an older adult with cancer may face is the mindset of their treating clinicians-a shared care approach between surgical oncologists and geriatricians is required.

Prehabilitation in adult patients undergoing surgery: an umbrella review of systematic reviews

BACKGROUND

The certainty that prehabilitation improves postoperative outcomes is not clear. The objective of this umbrella review (i.e. systematic review of systematic reviews) was to synthesise and evaluate evidence for prehabilitation in improving health, experience, or cost outcomes.

METHODS

We performed an umbrella review of prehabilitation systematic reviews. MEDLINE, Embase, Cochrane, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, Joanna Briggs Institute's database, and Web of Science were searched (inception to October 20, 2020). We included all systematic reviews of elective, adult patients undergoing surgery and exposed to a prehabilitation intervention, where health, experience, or cost outcomes were reported. Evidence certainty was assessed using Grading of Recommendations Assessment, Development and Evaluation. Primary syntheses of any prehabilitation were stratified by surgery type.

RESULTS

From 1412 titles, 55 systematic reviews were included. For patients with cancer undergoing surgery who participate in any prehabilitation, moderate certainty evidence supports improvements in functional recovery. Low to very low certainty evidence supports reductions in complications (mixed, cardiovascular, and cancer surgery), non-home discharge (orthopaedic surgery), and length of stay (mixed, cardiovascular, and cancer surgery). There was low to very low certainty evidence that exercise prehabilitation reduces the risk of complications, non-home discharge, and length of stay. There was low to very low certainty evidence that nutritional prehabilitation reduces risk of complications, mortality, and length of stay.

CONCLUSIONS

Low certainty evidence suggests that prehabilitation may improve postoperative outcomes. Future low risk of bias, randomised trials, synthesised using recommended standards, are required to inform practice. Optimal patient selection, intervention design, and intervention duration must also be determined.

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.

The Association Between Preoperative Frailty and Postoperative Delirium: A Systematic Review and Meta-analysis

PURPOSE

Identifying factors that place patients at high risk for developing postoperative delirium is an important first step to reduce incidence. Frailty is associated with poor postoperative outcomes. This meta-analysis aims to determine the association between preoperative frailty and postoperative delirium.

DESIGN

This is a systematic review and meta-analysis.

METHODS

We used PubMed, Scopus, Embase, CINAHL, Cochrane, and Web of Science as databases for the search up to April 23, 2020. We included cohort studies that assessed postoperative delirium as the outcome and described the prevalence of delirium among participants during the postoperative period. Odds ratio and 95% confidence interval were calculated to examine the association.

FINDINGS

Twenty cohort studies met our inclusion criteria, which included a total of 4,568 patients. We found that preoperative frailty was significantly associated with an increased risk of postoperative delirium (crude odds ratio: 3.28; 95% confidence interval: 2.51 to 4.28; I² = 46.7%) (adjusted odds ratio: 2.45; 95% confidence interval: 1.58 to 3.81; I² = 88.6%).

CONCLUSIONS

This meta-analysis showed that preoperative frailty is an independent risk factor for postoperative delirium. In patients undergoing cardiovascular surgery, there is a lower association between frailty and postoperative delirium. In patients with other types of surgery, preoperative frailty is closely related to postoperative delirium.

Carotid revascularization and cognitive impairment: the neglected role of cerebral small vessel disease

Carotid atherosclerosis is a pathological process that leads to narrowing of the vessel lumen and a consequent risk of stroke. Revascularization procedures such as carotid endarterectomy (CEA) and carotid stenting aim to reduce occurrence of stroke in selected patients. Due to the proven benefit and low intraoperative risk, CEA is currently the preferred choice in candidates for carotid revascularization. However, the risk of cognitive impairment subsequent to CEA has not been fully elucidated and is unclear whether certain conditions, such as frailty, may increase this risk. There is consistent evidence that shows that frail patients have higher risk of cognitive impairment after surgical procedure. Moreover, brain pre-existing conditions may play a role in cognitive impairment after CEA. Cerebral small vessel disease (SVD) is a pathology that involves microcirculation and is detectable with computed tomography or magnetic resonance. SVD shares common vascular risk factors with carotid atherosclerosis, is a major contributor to vascular cognitive impairment and vascular dementia, and has been proposed as a marker of brain frailty. In this review, we discuss the current evidence about the link between carotid revascularization and cognitive impairment and advance the hypothesis that SVD may play a relevant role in development of cognitive impairment after carotid revascularization.

Risk factors for postoperative delirium: An umbrella review of systematic reviews

BACKGROUND

Postoperative delirium (POD) is associated with increased mortality, increased length of hospital stays and increased rates and severity of subsequent cognitive decline including dementia. A wide range of risk factors for POD have been suggested in the literature across multiple surgical specialities. However few are validated and no accurate prognostic models exist. We therefore aimed to map the existing evidence regarding risk factors for POD to help guide future research by undertaking an umbrella review of systematic reviews examining risk factors for POD in any context.

MATERIALS AND METHODS

We systematically searched multiple medical databases for systematic reviews examining the risk factors for POD in adults undergoing any surgery. We then selected relevant reviews with minimal overlap in primary studies and extracted information about individual risk factors.

RESULTS

Thirty-five relevant reviews were identified of which ten were in trauma and orthopaedic surgery patients (four exclusively examined hip fractures), five were in cardiac surgery patients, and four were in vascular surgery patients. Due to substantial overlap in reviews, eighteen reviews were analysed in detail finding the widely examined and consistent risk factors were increasing age, nursing home residency, pre-existing cognitive impairment, psychiatric disorders, cerebrovascular disease, end stage renal failure, low albumin, higher ASA score, and intra-operative blood transfusion. Many other risk factors were examined, but they were either not studied in multiple systematic reviews, or inconsistent either in results or in categorisation (which for many factors was heterogenous even within systematic reviews). There are also a large number of existing prognostic models, many of which remain unvalidated.

CONCLUSION

Given the wealth of existing literature, future research should avoid simple risk factor evaluation except for novel candidates, validate existing prognostic models where possible, and instead focus on interventional research.

Development and validation of a risk score for predicting postoperative delirium after major abdominal surgery by incorporating preoperative risk factors and surgical Apgar score

STUDY OBJECTIVE

To develop and validate a simple delirium-predicting scoring system in patients undergoing major abdominal surgery by incorporating preoperative risk factors and intraoperative surgical Apgar score (SAS).

DESIGN

Observational retrospective cohort study.

SETTING

A tertiary general hospital in China.

PATIENTS

1055 patients who received major abdominal surgery from January 2015 to December 2019.

MEASUREMENTS

We collected data on preoperative and intraoperative variables, and postoperative delirium. A risk scoring system for postoperative delirium in patients after major open abdominal surgery was developed and validated based on traditional logistic regression model. The elastic net algorithm was further developed and evaluated.

MAIN RESULTS

The incidence of postoperative delirium was 17.8% (188/1055) in these patients. They were randomly divided into the development (n = 713) and validation (n = 342) cohorts. Both the logistic regression model and the elastic net regression model identified that advanced age, arrythmia, hypoalbuminemia, coagulation dysfunction, mental illness or cognitive impairments and low surgical Apgar score are related with increased risk of postoperative delirium. The elastic net algorithm has an area under the receiver operating characteristic curve (AUROC) of 0.842 and 0.822 in the development and validation cohorts, respectively. A prognostic score was calculated using the following formula: Prognostic score = Age classification (0 to 3 points) + arrythmia + 2 * hypoalbuminemia + 2 * coagulation dysfunction + 4 * mental illness or cognitive impairments + (10-surgical Apgar score). The 22-point risk scoring system had good discrimination and calibration with an AUROC of 0.823 and 0.834, and a non-significant Hosmer-Lemeshow test P = 0.317 and P = 0.853 in the development and validation cohorts, respectively. The bootstrapping internal verification method (R = 1000) yielded a C-index of 0.822 (95% CI: 0.759-0.857).

CONCLUSION

The prognostic scoring system, which used both preoperative risk factors and surgical Apgar score, serves as a good first step toward a clinically useful predictive model for postoperative delirium in patients undergoing major open abdominal surgery.

A Machine Learning Approach for Investigating Delirium as a Multifactorial Syndrome

Delirium is a psycho-organic syndrome common in hospitalized patients, especially the elderly, and is associated with poor clinical outcomes. This study aims to identify the predictors that are mostly associated with the risk of delirium episodes using a machine learning technique (MLT). A random forest (RF) algorithm was used to evaluate the association between the subject’s characteristics and the 4AT (the 4 A’s test) score screening tool for delirium. RF algorithm was implemented using information based on demographic characteristics, comorbidities, drugs and procedures. Of the 78 patients enrolled in the study, 49 (63%) were at risk for delirium, 32 (41%) had at least one episode of delirium during the hospitalization (38% in orthopedics and 31% both in internal medicine and in the geriatric ward). The model explained 75.8% of the variability of the 4AT score with a root mean squared error of 3.29. Higher age, the presence of dementia, physical restraint, diabetes and a lower degree are the variables associated with an increase of the 4AT score. Random forest is a valid method for investigating the patients’ characteristics associated with delirium onset also in small case-series. The use of this model may allow for early detection of delirium onset to plan the proper adjustment in healthcare assistance.

Postoperative delirium mediates 180-day mortality in orthopaedic trauma patients

BACKGROUND

Frailty has been associated with increased incidence of postoperative delirium and mortality. We hypothesised that postoperative delirium mediates a clinically significant (≥1%) percentage of the effect of frailty on mortality in older orthopaedic trauma patients.

METHODS

This was a single-centre, retrospective observational study including 558 adults 65 yr and older, who presented with an extremity fracture requiring hospitalisation without initial ICU admission. We used causal statistical inference methods to estimate the relationships between frailty, postoperative delirium, and mortality.

RESULTS

In the cohort, 180-day mortality rate was 6.5% (36/558). Frail and prefrail patients comprised 23% and 39%, respectively, of the study cohort. Frailty was associated with increased 180 day mortality from 1.4% to 12.2% (11% difference; 95% confidence interval [CI], 8.4-13.6), which translated statistically into an 88.7% (79.9-94.3%) direct effect and an 11.3% (5.7-20.1%) postoperative delirium mediated effect. Prefrailty was also associated with increased 180 day mortality from 1.4% to 4.4% (2.9% difference; 2.4-3.4), which was translated into a 92.5% (83.8-99.9%) direct effect and a 7.5% (0.1-16.2%) postoperative delirium mediated effect.

CONCLUSIONS

Frailty is associated with increased postoperative mortality, and delirium might mediate a clinically significant, but small percentage of this effect. Studies should assess whether, in patients with frailty, attempts to mitigate delirium might decrease postoperative mortality.

Risk factors and adverse clinical outcomes of postoperative delirium in Thai elderly patients: A prospective cohort study

PURPOSE

To determine the incidence, risk factors, and adverse clinical outcomes of postoperative delirium (POD) in elderly patients.

DESIGN AND METHODS

A total of 429 patients scheduled to undergo noncardiac surgery were recruited. Delirium was assessed using the confusion assessment method.

FINDINGS

The incidence of POD was 5.4%. Risk factors of POD were age over 70 years, an American Society of Anesthesiologist physical status 2 and 3, cognitive impairment, history of psychiatric illness, and preoperative hemoglobin ≤ 10 g/dl.

PRACTICE IMPLICATIONS

The correction of modifiable risk factors, the use of preventive strategies, and the monitoring of POD are advisable to improve the quality of perioperative care.

Risk Factors of Postoperative Delirium in Older Adult Spine Surgery Patients: A Meta-Analysis

This literature review identifies factors that may place older adult patients at risk for developing delirium after spine surgery. We conducted a meta-analysis according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Using a variety of electronic databases, we identified five studies for inclusion that represent 645 patients who were 65 years or older. The pooled incidence rate of postoperative delirium was 13.0%. Factors associated with developing postoperative delirium included preoperative opioid use, cervical spine surgery versus lumbar or thoracic spine surgery, spine fusion versus simple spine surgery, hypertension, cerebrovascular disease, pulmonary disease, duration of surgery, and infused IV fluid volume. Nurses who provide perioperative care for older adult patients undergoing spine surgery should be aware of the potential risk factors of delirium to ensure patient safety. Further research is required to clearly delineate the risk factors for postoperative delirium in older adults.