Risk Factors and Outcomes for Postoperative Delirium after Major Surgery in Elderly Patients

Does the melatonin receptor 1B gene polymorphism have a role in postoperative delirium?

INTRODUCTION

Patients undergoing cardiac surgery are at high risk for postoperative delirium, which is associated with longer hospital and intensive care lengths of stays, increased morbidity and mortality. Because sleep disturbances are common in delirium, melatonin has been an area of interest in the treatment of delirium. The rs10830963 single nucleotide polymorphism of the melatonin receptor 1B gene can cause pathological dysfunction of this receptor and is associated with delayed morning offset of melatonin. We hypothesized patients undergoing aortic cardiac surgery who have the risk genotype of a melatonin receptor 1B polymorphism would have a higher incidence of postoperative delirium.

METHODS

Ninety-eight patients undergoing aortic root or valve surgery underwent analysis for melatonin receptor 1B single nucleotide polymorphism, rs10830963. Using a validated method, CHART-DEL, all charts were retrospectively reviewed and scored for the presence of delirium while blinded to the results of the melatonin receptor 1B gene polymorphism.

RESULTS

Genotyping for melatonin receptor 1B polymorphism was acceptable in 76 subjects of European descent of which 18 (23.7%) had delirium. Four of seven subjects with the risk genotype had delirium versus only 20.3% of subjects without the risk genotype. This carried an odds ratio of 5.2 (1.0, 26.1), p = 0.050.

CONCLUSION

This observation suggests a role of the risk genotype of a melatonin receptor 1B polymorphism in the development of postoperative delirium. These hypotheses generating results warrant further prospective studies in a larger cohort group with delirium, circadian rhythm and melatonin assessments.

Low skeletal muscle mass as a risk factor for postoperative delirium in elderly patients undergoing colorectal cancer surgery

Background

Both low skeletal muscle mass (LSMM) and delirium are frequently seen in elderly patients. This study aimed to investigate the association between preoperative LSMM and postoperative delirium (POD) in elderly patients undergoing colorectal cancer (CRC) surgery and to design a model to predict POD.

Patients and methods

This is a retrospective observational cohort study. Patients aged 70 years or older undergoing CRC surgery from January 2013 to October 2015 were included in this study. The cross-sectional skeletal muscle area at the level of the third lumbar vertebra using computed tomography was adjusted for patients' height, resulting in the skeletal muscle index. The lowest quartile per sex was defined as LSMM. Short Nutritional Assessment Questionnaire for Residential Care and KATZ-Activities of Daily Living were used to define malnourishment and physical dependency, respectively. POD was diagnosed using the Delirium Observational Screening Scale and geriatricians' notes.

Results

Median age of the 251 included patients was 76 years (IQR, 73-80 years), of whom 56% of patients were males, 24% malnourished, and 15% physically impaired. LSMM and POD were diagnosed in 65 and 33 (13%) patients, respectively. POD occurred significantly more in patients with LSMM (25%) compared with patients without LSMM (10%), P=0.006. In the multivariate analysis, age, history of delirium, and LSMM were significantly associated with POD. In addition, this effect increased in patients with LSMM and malnourishment (P=0.019) or physical dependency (P=0.017).

Conclusion

Age, history of delirium, LSMM, and malnourishment or physical dependency were independently associated with POD. Our nomogram could be used to identify patients at an increased risk for delirium. These patients may benefit from intensive monitoring to prevent POD.

Addition of Suvorexant to Ramelteon Therapy for Improved Sleep Quality with Reduced Delirium Risk in Acute Stroke Patients

BACKGROUND AND PURPOSE

Delirium in acute stroke is associated with poor clinical outcome. The purpose of this study was to examine the effect of sleep medications on sleep quality and delirium in acute stroke.

METHODS

In this retrospective cohort study, sleep disturbances, and delirium were investigated in acute stroke patients treated in April 2013-March 2017 who were prescribed ramelteon plus either an alpha-aminobutyric acid receptor (GABAR) agonist or a selective dual orexin receptor antagonist (suvorexant).

RESULTS

Of the patients included, 104 received a GABAR agonist and 128 received suvorexant in addition to ramelteon. Patient characteristics did not differ significantly between the groups, except for a higher proportion of cerebral infarction in suvorexant group (P = .033). Subjective sleep quality was significantly improved in suvorexant group compared to GABAR agonist group (difficulty staying asleep: 6.3% versus 34%, P < .001; daytime sleepiness: 33% versus 63%, P < .001). Delirium was significantly less frequent in suvorexant group than GABAR agonist group (7.0% versus 31%, P < .001). The length of hospital stay was significantly shorter in suvorexant group than in GABAR agonist group (in days, 21 [15-29] versus 25 [18-33]; P = .019). Multivariable logistic regression analysis revealed that the addition of suvorexant was significantly associated with a reduced occurrence of delirium (odds ratios .19, 95% confidence interval .085-.43, P < .001).

CONCLUSIONS

Addition of suvorexant to ramelteon therapy, rather than a GABA receptor agonist, can improve subjective sleep quality without inducing delirium in acute stroke patients.

Remifentanil suppresses increase in interleukin-6 mRNA in the brain by inhibiting cyclic AMP synthesis

PURPOSE

Neuronal inflammation is caused by systemic inflammation and induces cognitive dysfunction. IL-6 plays a crucial role in therapies for neuronal inflammation and cognitive dysfunction. Remifentanil, an ultra-short-acting opioid, controls inflammatory reactions in the periphery, but not in the brain. Therefore, the anti-inflammatory effects of remifentanil in neuronal tissue and the involvement of cAMP in these effects were investigated in the present study.

METHODS

Mice were divided into 4 groups: control, remifentanil, LPS, and LPS + remifentanil. Brain levels of pro-inflammatory cytokine mRNA, and serum levels of corticosterone, catecholamine and IL-6 were measured in the 4 groups. The co-localization of IL-6 and astrocytes in the mouse brain after the LPS injection was validated by immunostaining. LPS and/or remifentanil-induced changes in intracellular cAMP levels in cultured glial cells were measured, and the effects of cAMP on LPS-induced IL-6 mRNA expression levels were evaluated.

RESULTS

Remifentanil suppressed increase in IL-6 mRNA levels in the mouse brain, and also inhibited the responses of plasma IL-6, corticosterone, and noradrenaline in an inflammatory state. In the hypothalamus, IL-6 was localized in the median eminence, at which GFAP immunoreactivity was specifically detected. In cultured cells, remifentanil suppressed increase in IL-6 mRNA levels and intracellular cAMP levels after the administration of LPS, and this enhanced IL-6 mRNA expression in response to LPS.

CONCLUSION

Remifentanil suppressed increase in IL-6 mRNA levels in the brain in an inflammatory state, and this effect may be attributed to its direct action on neuronal cells through the inhibition of intracellular cAMP rather than corticosterone.

Anesthesia and surgery induce delirium-like behavior in susceptible mice: the role of oxidative stress

Anesthesia and surgery (A + S) are risk factors for patients to develop postoperative delirium (POD). However, the pathogenesis of POD remains largely to be determined. We employed battery of behavioral tests including open-filed test (OFT), elevated plus maze test (EPMT) and buried food test (BFT) to investigate the role of oxidative stress in the development of POD and to explore the therapeutic target for POD in mice after A + S (simple laparotomy under 1.4% isoflurane anesthesia). We initially found that 6 hours after A + S, mice failed to alter the behavioral changes in OFT and the adenosine triphosphate (ATP) level in hippocampus. After hierarchical cluster analysis, however, there was a significant change in the behavior tests between POD unsusceptible (non-POD) and susceptible (POD-like) mice. Interestingly, cyclosporine A, an inhibitor of mitochondrial permeability transition pore (mPTP) opening, exerted pharmacologically beneficial effects on symptoms, decreased reactive oxygen species (ROS) and ATP, and increased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) levels in the hippocampus of POD-like mice. These findings suggest that abnormally activated oxidative stress might be involved in the underlying mechanisms of POD. Novel therapeutic agents targeting inhibition of oxidative stress would provide an available strategy for POD treatment.

Incidence and risk factors of subsyndromal delirium after curative resection of gastric cancer

Background

Subsyndromal delirium, a condition in which patients exhibit some, but not all, of the symptoms of delirium, can negatively affect the outcomes of patients with cancer. However, the incidence of subsyndromal delirium in patients with gastric cancer is unknown. Here, we investigated the incidence and risk factors of subsyndromal delirium after curative resection of gastric cancer.

Methods

We recruited consecutive patients with gastric cancer who were scheduled for curative resection at a tertiary hospital. Patients’ subsyndromal delirium symptoms were serially assessed preoperatively and 1, 2, 3, and 7 days postoperatively using the Delirium Rating Scale-Revised-98 (DRS-R-98). A DRS-R-98 score of 8–14 at any postoperative assessment was considered to indicate subsyndromal delirium. Sociodemographic and pre−/intra-operative clinical data were also assessed. Logistic regression analyses were used to determine the associated risk factors.

Results

Data were analysed from 163 out of 217 eligible patients. Postoperative delirium occurred in one patient (0.6%) and subsyndromal delirium occurred in 19 patients (11.7%). Age ≥ 70 years (odds ratio, [OR] 3.85; 95% confidence interval [CI], 1.36–10.92; p = 0.011) and education level ≤ 9 years (OR, 3.98; 95% CI, 1.39–11.41; p = 0.010) were independent risk factors of subsyndromal delirium after adjusting for preoperative cognitive function. Other pre−/intra-operative variables including anxiety/depression, poor sleep quality, and anaesthesia duration were not associated with subsyndromal delirium.

Conclusions

In contrast to the low incidence of delirium among patients undergoing curative resection of gastric cancer, a substantial proportion of such patients experienced subsyndromal delirium. Considering the prognostic implications, more careful detection and management of subsyndromal delirium may be warranted in patients with gastric cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4681-2) contains supplementary material, which is available to authorized users.

Self-reported mobility as a preoperative risk assessment tool in older surgical patients compared to the American College of Surgeons National Surgical Quality Improvement Program

Background

The American College of Surgeons National Surgical Quality Improvement Program (NSQIP®) developed a surgical risk calculator using data from 1.4 million patients and including 1557 unique Current Procedural Terminology (CPT) codes. Although this calculator demonstrated excellent performance in predicting postoperative mortality, morbidity, and six surgical complications, it was not developed specifically for use in older surgical patients who have worse surgical outcomes and additional unique risk factors compared to younger adults. We aimed to test the ability of a simple self-reported mobility tool to predict postoperative outcomes in the older surgical population compared to the NSQIP.

Methods

We used data from a prospective cohort study that enrolled 197 older surgical patients (≥ 69 years) undergoing various elective surgeries and assessed 30-day surgical outcomes. Statistical models included data from the Mobility Assessment Tool-short form (MAT-sf) alone, covariates alone, and MAT-sf data and covariates. We used leave-one-out (LOO) cross-validation of the models within our cohort and compared their performance for predicting postoperative outcomes against the NSQIP calculator based on receiver operating characteristic area under the curve (ROC AUC).

Results

Patients with poor self-reported mobility experienced higher rates of postoperative complications and nursing home placement. There was no difference in performance between any of our models and the NSQIP calculator (p > 0.1), with AUC between 0.604 and 0.697 for predicting postoperative complications and 0.653 and 0.760 for predicting nursing home placement. All models also predicted a length of stay (LOS) similar to the actual LOS.

Conclusion

Mobility assessment alone using MAT-sf can predict postoperative complications, nursing home placement, and LOS for older surgical patients, with accuracy comparable to that of the NSQIP calculator. The simplicity of this noninvasive risk assessment tool makes it an attractive alternative to the NSQIP calculator that requires 20 patient predictors and the planned procedure, or CPT code to predict the chance that patients will have 15 different adverse outcomes following surgery.

Cholinesterase inhibitors for the treatment of delirium in non-ICU settings

BACKGROUND

Delirium is a common clinical syndrome defined as alterations in attention with an additional disturbance in cognition or perception, which develop over a short period of time and tend to fluctuate during the course of the episode. Delirium is commonly treated in hospitals or community settings and is often associated with multiple adverse outcomes such as increased cost, morbidity, and even mortality. The first-line intervention involves a multicomponent non-pharmacological approach that includes ensuring effective communication and reorientation in addition to providing reassurance or a suitable care environment. There are currently no drugs approved specifically for the treatment of delirium. Clinically, however, various medications are employed to provide symptomatic relief, such as antipsychotic medications and cholinesterase inhibitors, among others.

OBJECTIVES

To evaluate the effectiveness and safety of cholinesterase inhibitors for treating people with established delirium in a non-intensive care unit (ICU) setting.

SEARCH METHODS

We searched ALOIS, which is the Cochrane Dementia and Cognitive Improvement Group's Specialised Register, on 26 October 2017. We also cross-checked the reference lists of included studies to identify any potentially eligible trials.

SELECTION CRITERIA

We included randomised controlled trials, published or unpublished, reported in English or Chinese, which compared cholinesterase inhibitors to placebo or other drugs intended to treat people with established delirium in a non-ICU setting.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. The primary outcomes were duration of delirium, severity of delirium, and adverse events. The secondary outcomes were use of rescue medications, persistent cognitive impairment, length of hospitalisation, institutionalisation, mortality, cost of intervention, leaving the study early, and quality of life. For dichotomous outcomes, we calculated the risk ratio (RR) with 95% confidence intervals (CIs); for continuous outcomes we calculated the mean difference (MD) with 95% CIs. We assessed the quality of evidence using GRADE to generate a 'Summary of findings' table.

MAIN RESULTS

We included one study involving 15 participants from the UK. The included participants were diagnosed with delirium based on the Confusion Assessment Method (CAM) criteria. Eight males and seven females were included, with a mean age of 82.5 years. Seven of the 15 participants had comorbid dementia at baseline. The risk of bias was low in all domains.The study compared rivastigmine with placebo. We did not find any clear differences between the two groups in terms of duration of delirium (MD -3.6, 95% CI -15.6 to 8.4), adverse events (nausea, RR 0.30, 95% CI 0.01 to 6.29), use of rescue medications (RR 0.13, 95% CI 0.01 to 2.1), mortality (RR 0.10, 95% CI 0.01 to 1.56), and leaving the study early (RR 0.88, 95% CI 0.07 to 11.54). Evidence was not available regarding the severity of delirium, persistent cognitive impairment, length of hospitalisation, cost of intervention, or other predefined secondary outcomes.The quality of evidence is low due to the very small sample size.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the use of cholinesterase inhibitors for the treatment of delirium in non-ICU settings. No clear benefits or harms associated with cholinesterase inhibitors were observed when compared with placebo due to the lack of data. More trials are required.

Delirium in Postoperative Patients Admitted to the Intensive Care Unit

Postoperative delirium (POD) is common among surgical patients admitted to the intensive care unit (ICU) and is associated with increased resource utilization, morbidity, and death. Our primary aim was to compare rates of POD using administrative International Classification of Diseases, Ninth Revision, records and automated interrogation of electronic health records from Confusion Assessment Method for the ICU (CAM-ICU) screening. The secondary aim was to assess POD risk associated with patient and perioperative characteristics. Electronic health records of surgical patients admitted to the ICU during 2011 through 2014 were abstracted for POD assessment by CAM-ICU and by administrative codes, Charlson comorbidity index, surgical characteristics, and Acute Physiology, Age, Chronic Health Evaluation III scores. Of 6338 patients, CAM-ICU identified 606 (9.6%) and administrative records identified 55 (0.9%) POD cases, with agreement on 50 cases. In multivariable logistic regression based on POD identified with CAM-ICU, preexisting dementia had the strongest association with POD (odds ratio [95% confidence interval], 6.47 [3.68–11.37]; P < 0.001). Other associations found were older age, congestive heart failure, chronic pulmonary disease, increased surgical duration, emergency cases, blood transfusions, postoperative ventilation, and higher Acute Physiology, Age, Chronic Health Evaluation III scores (all P ≤ 0.01). POD cases had lengthier ICU and hospital stays and a higher mortality rate (all P < 0.001). CAM-ICU scores identified higher rates of POD than a search for POD based on administrative codes. Preoperative presence of dementia and major comorbidities were associated with POD. Delirium in surgical patients is associated with worse outcomes.

Incidence, Risk Factors, and Sequelae of Post-kidney Transplant Delirium

Background Frail kidney transplant (KT) recipients may be particularly vulnerable to surgical stressors, resulting in delirium and subsequent adverse outcomes. We sought to identify the incidence, risk factors, and sequelae of post-KT delirium.Methods We studied 125,304 adult KT recipients (1999-2014) to estimate delirium incidence in national registry claims. Additionally, we used a validated chart abstraction algorithm to identify post-KT delirium in 893 adult recipients (2009-2017) from a cohort study of frailty. Delirium sequelae were identified using adjusted logistic regression (length of stay ≥2 weeks and institutional discharge [skilled nursing or rehabilitation facility]) and adjusted Cox regression (death-censored graft loss and mortality).Results Only 0.8% of KT recipients had a delirium claim. In the cohort study, delirium incidence increased with age (18-49 years old: 2.0%; 50-64 years old: 4.6%; 65-75 years old: 9.2%; and ≥75 years old: 13.8%) and frailty (9.0% versus 3.9%); 20.0% of frail recipients aged ≥75 years old experienced delirium. Frailty was independently associated with delirium (odds ratio [OR], 2.05; 95% confidence interval [95% CI], 1.02 to 4.13; P=0.04), but premorbid global cognitive function was not. Recipients with delirium had increased risks of ≥2-week length of stay (OR, 5.42; 95% CI, 2.76 to 10.66; P<0.001), institutional discharge (OR, 22.41; 95% CI, 7.85 to 63.98; P<0.001), graft loss (hazard ratio [HR], 2.73; 95% CI, 1.14 to 6.53; P=0.03), and mortality (HR, 3.12; 95% CI, 1.76 to 5.54; P<0.001).Conclusions Post-KT delirium is a strong risk factor for subsequent adverse outcomes, yet it is a clinical entity that is often missed.

Neurological Sequelae and Clinical Outcomes After Lung Transplantation

Background

Neurological complications are common after lung transplantation. However, no large cohort studies have examined the incidence, predictors, and clinical significance of neurological events sustained by lung transplant recipients.

Methods

We conducted a retrospective cohort analysis of a consecutive series of lung transplant recipients, transplanted at Duke University Medical Center between May 2014 and February 2017 (n = 276). Early neurological complications (ie, occurring during the first week after transplant) were documented by transplant mental health specialists and included delirium, ischemic injury, and posterior reversible encephalopathy syndrome. Analyses accounted for age, native disease, sex, type of transplant, lung allocation score, and primary graft dysfunction. The objectives of the study were to characterize the prevalence and predictors of early neurological sequelae (NSE), occurring during the first week posttransplant, and the association between NSE and subsequent clinical outcomes, including length of stay and mortality.

Results

Neurological sequelae were common, occurring in 123 (45%) patients. Fifty-seven patients died over a follow-up interval of 2.1 years. The most common NSE were postoperative delirium (n = 110 [40%]) and posterior reversible encephalopathy syndrome (n = 12 [4%]), followed by stroke/transient ischemic attack and neurotoxicity. Higher lung allocation score was the strongest predictor of delirium. The presence of a NSE was associated with longer length of hospital stay (32 days vs 17 days, P < 0.001) and greater mortality (hazard ratio, 1.90; 95% confidence interval, 1.09-3.32], P = 0.024), with the greatest mortality risk occurring approximately 2 years after transplantation.

Conclusions

Neurological events are relatively common after lung transplantation and associated with adverse clinical outcomes.

Nurses and physiotherapists' experience in mobilising postoperative orthopaedic patients with altered mental status: A phenomenological study

BACKGROUND

A major goal of care for orthopaedic surgical patients is the achievement of their pre-morbid functional level or at least an improvement of their functional ability. However, patients with altered mental status can significantly impact this and other outcomes and influence the delivery of care. Patient mobilisation is a role shared by both nurses and physiotherapists.

AIMS

To enhance the understanding of nurses and physiotherapists' experience in mobilising postoperative orthopaedic patients with altered mental status.

METHOD

Three nurses and three physiotherapists were recruited using purposive sampling. Data was collected through interviews and analysed using Burnard's 14 stages of thematic content analysis.

RESULTS

Four main categories emerged from the study: altruism, interprofessional specialist practice, patient dynamics and challenges. Nurses and physiotherapists' experience have more similarities than differences under the four categories.

CONCLUSION

Nurses and physiotherapists experience numerous challenges from both patient and resources related factors such as environment, staffing and time limitations; safety risks to patient and staff; and communication barriers due to patient's altered mental state. While tensions and variations in priorities of care delivery exist between the two groups, interdisciplinary collaboration of both professional groups was clearly evident and enabled optimisation of mobilisation goals for this patient population and revealed more similarities than differences in their experience. Patient and staff safety takes precedence over mobilisation and safety risks in this patient group can be mitigated by adequate resources, competence, and teamwork.

Protocol for a single-centre prospective observational study of postoperative delirium following total joint arthroplasties among South East Asians

INTRODUCTION

Postoperative delirium is a serious and common complication in older adults following total joint arthroplasties (TJA). It is associated with increased risk of postoperative complications, mortality, length of hospital stay and postdischarge institutionalisation. Thus, it has a negative impact on the health-related quality of life of the patient and poses a large economic burden. This study aims to characterise the incidence of postoperative delirium following TJA in the South East Asian population and investigate any risk factors or associated outcomes.

METHODS AND ANALYSIS

This is a single-centre prospective observational study recruiting patients between 65 and 90 years old undergoing elective total knee arthroplasty or total hip arthroplasty. Exclusion criteria included patients with clinically diagnosed dementia. Preoperative and intraoperative data will be obtained prospectively. The primary outcome will be the presence of postoperative delirium assessed using the Confusion Assessment Method on postoperative days 1, 2 and 3 and day of discharge. Other secondary outcomes assessed postoperatively will include hospital outcomes, pain at rest, knee and hip function, health-related quality of life and Postoperative Morbidity Survey-defined morbidity. Data will be analysed to calculate the incidence of postoperative delirium. Potential risk factors and any associated outcomes of postoperative delirium will also be determined.

ETHICS AND DISSEMINATION

This study has been approved by the Singapore General Hospital Institutional Review Board (SGH IRB) (CIRB Ref: 2017/2467) and is registered on the ClinicalTrials.gov registry (Identified: NCT03260218). An informed consent form will be signed by all participants before recruitment and translators will be made available to non-English-speaking participants. The results of this study will be presented at international conferences and submitted to a peer-reviewed journal. The data collected will also be made available in a public data repository.

TRIAL REGISTRATION NUMBER

NCT03260218.

Impact of hypotension and global hypoperfusion in postoperative delirium: a pilot study in older adults undergoing open colon surgery

Background

Post-operative delirium is a serious complication in patients undergoing major abdominal surgery. It remains unclear whether peri-operative hemodynamic and perfusion variables affect the risk for postoperative delirium. The objective of this pilot study was to evaluate the association between perfusion and hemodynamics peri-operative with the appearance of post-operative delirium.

Methods

Prospective cohort study of adults 60 years or older undergoing elective open colon surgery. Multimodal hemodynamic and perfusion variables were monitored, including central venous oxygenation (ScvO₂), lactate levels, and non-invasive cerebral oxygenation (rSO₂), according to a standard anesthesia protocol. Fisher's exact test or Student's t-test were used to compare patients who developed post-operative delirium with those who did not (p < 0.05).

Results

We studied 28 patients, age 73 ± 7 years, 60.7% female. Two patients developed post-operative delirium (7.1%). These two patients had fewer years of education than those without delirium (p = 0.031). None of the peri-operative blood pressure variables were associated with incidence of post-operative delirium. In terms of perfusion parameters, postoperative ScvO₂ was lower in the delirium than the non-delirium group, without reaching statistical significance (65 ± 10% vs. 74 ± 5%; p = 0.08), but the delta-ScvO₂ (the difference between means post-operative and intra-operative) was associated with post-operative delirium (p = 0.043). Post-operative lactate and rSO₂ variables were not associated with delirium.

Conclusions

Our pilot study suggests an association between delta ScvO₂ and post-operative delirium, and a tendency to lower post-operative ScvO₂ in patients who developed delirium. Further studies are necessary to elucidate this association.

[Impact of hypotension and global hypoperfusion in postoperative delirium: a pilot study in older adults undergoing open colon surgery]

BACKGROUND

Post-operative delirium is a serious complication in patients undergoing major abdominal surgery. It remains unclear whether peri-operative hemodynamic and perfusion variables affect the risk for postoperative delirium. The objective of this pilot study was to evaluate the association between perfusion and hemodynamics peri-operative with the appearance of post-operative delirium.

METHODS

Prospective cohort study of adults 60 years or older undergoing elective open colon surgery. Multimodal hemodynamic and perfusion variables were monitored, including central venous oxygenation (ScvO₂), lactate levels, and non-invasive cerebral oxygenation (rSO₂), according to a standard anesthesia protocol. Fisher's exact test or Student's t-test were used to compare patients who developed post-operative delirium with those who did not (p<0.05).

RESULTS

We studied 28 patients, age 73±7 years, 60.7% female. Two patients developed post-operative delirium (7.1%). These two patients had fewer years of education than those without delirium (p=0.031). None of the peri-operative blood pressure variables were associated with incidence of post-operative delirium. In terms of perfusion parameters, postoperative ScvO₂ was lower in the delirium than the non-delirium group, without reaching statistical significance (65±10% vs. 74±5%; p=0.08), but the delta-ScvO₂ (the difference between means post-operative and intra-operative) was associated with post-operative delirium (p=0.043). Post-operative lactate and rSO₂ variables were not associated with delirium.

CONCLUSIONS

Our pilot study suggests an association between delta ScvO₂ and post-operative delirium, and a tendency to lower post-operative ScvO₂ in patients who developed delirium. Further studies are necessary to elucidate this association.

Using anchors from free text in electronic health records to diagnose postoperative delirium

OBJECTIVES

Postoperative delirium is a common complication after major surgery among the elderly. Despite its potentially serious consequences, the complication often goes undetected and undiagnosed. In order to provide diagnosis support one could potentially exploit the information hidden in free text documents from electronic health records using data-driven clinical decision support tools. However, these tools depend on labeled training data and can be both time consuming and expensive to create.

METHODS

The recent learning with anchors framework resolves this problem by transforming key observations (anchors) into labels. This is a promising framework, but it is heavily reliant on clinicians knowledge for specifying good anchor choices in order to perform well. In this paper we propose a novel method for specifying anchors from free text documents, following an exploratory data analysis approach based on clustering and data visualization techniques. We investigate the use of the new framework as a way to detect postoperative delirium.

RESULTS

By applying the proposed method to medical data gathered from a Norwegian university hospital, we increase the area under the precision-recall curve from 0.51 to 0.96 compared to baselines.

CONCLUSIONS

The proposed approach can be used as a framework for clinical decision support for postoperative delirium.

Association between baseline cognitive impairment and postoperative delirium in elderly patients undergoing surgery for adult spinal deformity

OBJECTIVE Postoperative delirium is common in elderly patients undergoing spine surgery and is associated with a longer and more costly hospital course, functional decline, postoperative institutionalization, and higher likelihood of death within 6 months of discharge. Preoperative cognitive impairment may be a risk factor for the development of postoperative delirium. The aim of this study was to investigate the relationship between baseline cognitive impairment and postoperative delirium in geriatric patients undergoing surgery for degenerative scoliosis. METHODS Elderly patients 65 years and older undergoing a planned elective spinal surgery for correction of adult degenerative scoliosis were enrolled in this study. Preoperative cognition was assessed using the validated Saint Louis University Mental Status (SLUMS) examination. SLUMS comprises 11 questions, with a maximum score of 30 points. Mild cognitive impairment was defined as a SLUMS score between 21 and 26 points, while severe cognitive impairment was defined as a SLUMS score of ≤ 20 points. Normal cognition was defined as a SLUMS score of ≥ 27 points. Delirium was assessed daily using the Confusion Assessment Method (CAM) and rated as absent or present on the basis of CAM. The incidence of delirium was compared in patients with and without baseline cognitive impairment. RESULTS Twenty-two patients (18%) developed delirium postoperatively. Baseline demographics, including age, sex, comorbidities, and perioperative variables, were similar in patients with and without delirium. The length of in-hospital stay (mean 5.33 days vs 5.48 days) and 30-day hospital readmission rates (12.28% vs 12%) were similar between patients with and without delirium, respectively. Patients with preoperative cognitive impairment (i.e., a lower SLUMS score) had a higher incidence of postoperative delirium. One- and 2-year patient reported outcomes scores were similar in patients with and without delirium. CONCLUSIONS Cognitive impairment is a risk factor for the development of postoperative delirium. Postoperative delirium may be associated with decreased preoperative cognitive reserve. Cognitive impairment assessments should be considered in the preoperative evaluations of elderly patients prior to surgery.

Early postoperative delirium after hemiarthroplasty in elderly patients aged over 70 years with displaced femoral neck fracture

Purpose

Postoperative delirium is a risk factor for worse outcome after hip fracture surgery in elderly patients. Postoperative delirium is associated with anesthesia, postoperative pain, and patient factors. We investigated the incidence, predictors, and prognostic implications of post-operative delirium after hemiarthroplasty (HA) in elderly patients with femoral neck fracture.

Patients and methods

A total of 356 consecutive patients aged >70 years who underwent HA for femoral neck fracture were enrolled. Diagnosis of delirium was made by a psychiatrist based on patient status and an objective scoring system. The patients were divided into 2 categories according to the HA onset time (immediate [≤24 h after surgery] vs delayed delirium [>24 h after surgery]) and its incidence, predictors and mortality were evaluated.

Results

Postoperative delirium was diagnosed in 110 patients (30.9%) during hospitalization. Immediate and delayed delirium occurred in 59 (53.6%), and 51 (46.4%) patients, respectively. The independent predictors of immediate delirium included age (odds ratio [OR] 1.47, 95% CI 0.98–2.23, p=0.066), and general anesthesia (OR 2.25, 95% CI 1.17–4.43, p=0.015). The independent predictors of delayed delirium were parkinsonism (OR 5.75, 95% CI 1.66–19.96, p=0.006), intensive care unit stay (OR 1.85, 95% CI 0.97–3.56, p=0.064), and higher American Society of Anesthesiologists grade (OR 2.33, 95% CI 0.90–6.07, p=0.083). On Kaplan–Meier survival analysis, the 2-year survival rate was significantly lower in the immediate delirium group than those in the delayed and control groups (71.0% vs 83.6% vs 87.8%, respectively; p=0.031).

Conclusion

Immediate and delayed delirium after HA for femoral neck fracture had different predictors and immediate delirium was associated with worse prognosis.

Preoperative medication use and its association with postoperative length of hospital stay in surgical oncology patients receiving comprehensive geriatric assessment

AIM

The present study aimed to investigate whether preoperative medication use is associated with postoperative length of hospital stay in older adults undergoing cancer surgery.

METHODS

Patients aged ≥65 years who were scheduled for cancer surgery and presented for preoperative comprehensive geriatric assessment were included in the present study. Cognitive function evaluation and preoperative medication review were carried out, as well as baseline characteristics of participants collected from electronic medical records. The primary efficacy variable was the postoperative length of stay (LOS) in hospital.

RESULTS

A total of 475 cancer patients were included for the analysis. Baseline characteristics of participants including older age, lower body mass index (BMI) and male sex were associated with longer postoperative stay. Among the clinical variables, cancer type, number of medications, potentially inappropriate medication (PIM) and delirium-inducing medication were found as statistically significant factors for postoperative LOS. In multivariate analysis, variables independently associated with postoperative LOS were cancer type, PIM use, BMI, and the number of medications after controlling for age, BMI, sex, cancer type, the number of medications, PIM, and delirium-inducing medication. In subgroup analysis of gastrointestinal cancer, multiple linear regression analysis showed that PIM use and BMI were significantly associated with LOS after adjustment for age, sex, and number of medication.

CONCLUSIONS

The present study supports the impact of medication use on postoperative LOS in geriatric oncology patients. The results add a further aspect to medication optimization in older patients undergoing cancer surgery. Geriatr Gerontol Int 2018; 18: 12-19.

A Systematic Review and Meta-analysis Examining the Impact of Incident Postoperative Delirium on Mortality

Background

Delirium is an acute and reversible geriatric syndrome that represents a decompensation of cerebral function. Delirium is associated with adverse postoperative outcomes, but controversy exists regarding whether delirium is an independent predictor of mortality. Thus, we assessed the association between incident postoperative delirium and mortality in adult noncardiac surgery patients.

Methods

A systematic search was conducted using Cochrane, MEDLINE/PubMed, Cumulative Index to Nursing and Allied Health Literature, and Embase. Screening and data extraction were conducted by two independent reviewers. Pooled-effect estimates calculated with a random-effects model were expressed as odds ratios with 95% CIs. Risk of bias was assessed using the Cochrane Risk of Bias Tool for Non-Randomized Studies.

Results

A total of 34 of 4,968 screened citations met inclusion criteria. Risk of bias ranged from moderate to critical. Pooled analysis of unadjusted event rates (5,545 patients) suggested that delirium was associated with a four-fold increase in the odds of death (odds ratio = 4.12 [95% CI, 3.29 to 5.17]; I2 = 24.9%). A formal pooled analysis of adjusted outcomes was not possible due to heterogeneity of effect measures reported. However, in studies that controlled for prespecified confounders, none found a statistically significant association between incident postoperative delirium and mortality (two studies in hip fractures; n = 729) after an average follow-up of 21 months. Overall, as study risk of bias decreased, the association between delirium and mortality decreased.

Conclusions

Few high-quality studies are available to estimate the impact of incident postoperative delirium on mortality. Studies that controlled for prespecified confounders did not demonstrate significant independent associations of delirium with mortality.

Dementia and delirium, the outcomes in elderly hip fracture patients

BACKGROUND

Delirium in hip fractured patients is a frequent complication. Dementia is an important risk factor for delirium and is common in frail elderly. This study aimed to extend the previous knowledge on risk factors for delirium and the consequences. Special attention was given to patients with dementia and delirium.

METHODS

This is a retrospective cohort study performed in the Amphia Hospital, Breda, the Netherlands. A full electronic patient file system (Hyperspace Version IU4: Epic, Inc., Verona, WI, USA) was used to assess data between January 2014 and September 2015. All patients presented were aged ≥70 years with a hip fracture, who underwent surgery with osteosynthesis or arthroplasty. Patients were excluded in case of a pathological or a periprosthetic hip fracture, multiple traumatic injuries, and high-energy trauma. Patient and surgical characteristics were documented. Postoperative outcomes were noted. Delirium was screened using Delirium Observation Screening Scale and dementia was assessed from medical notes.

RESULTS

Of a total of 566 included patients, 75% were females. The median age was 84 years (interquartile range: 9). Delirium was observed in 35%. Significant risk factors for delirium were a high American Society of Anesthesiology score, delirium in medical history, functional dependency, preoperative institutionalization, low hemoglobin level, and high amount of blood transfusion. Delirium was correlated with a longer hospital stay (P=0.001), increased association with complications (P<0.001), institutionalization (P<0.001), and 6-month mortality (P<0.001). Patients with dementia (N=168) had a higher delirium rate (57.7%, P<0.001) but a shorter hospital stay (P<0.001). There was no significant difference in the 6-month mortality between delirious patients with (34.0%) and without dementia (26.3%).

CONCLUSION

Elderly patients with a hip fracture are vulnerable for delirium, especially when the patient has dementia. Patients who underwent an episode of delirium were at increased risk for adverse outcomes.

The Impact of Comorbidity on Surgical Outcomes in Older Adults with Cancer

OBJECTIVES

To provide an overview of the impact of comorbidity on surgical outcomes and postoperative geriatric events in older adults with cancer, and review key components of quality perioperative nursing care of older adults with cancer.

DATA SOURCES

Journal articles, research reports, state of the science papers, position papers, and clinical guidelines from professional organizations.

CONCLUSION

The high prevalence of multiple comorbidities and the associated burden of geriatric events in older adults after cancer surgery have a substantial impact on surgical outcomes, quality of life, and health care costs. Practical and efficient models of comprehensive assessment, prevention, and management of postoperative geriatric events and comorbid conditions are needed to improve surgical outcomes for this vulnerable cancer population.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses practicing in clinical and research settings have a responsibility to arm themselves with evidence-based knowledge and resources to improve the perioperative care of older adults with cancer.

No convincing association between post-operative delirium and post-operative cognitive dysfunction: a secondary analysis

BACKGROUND

Post-operative delirium and post-operative cognitive dysfunction (POCD) are both common but it has not been clarified how closely they are associated. We aimed to assess the possible relationship in a secondary analysis of data from the 'Surgery Depth of anaesthesia and Cognitive outcome'- study.

METHODS

We included patients aged ≥ 60 years undergoing non-cardiac surgery planned for longer than 60 min. Delirium was assessed according to the Diagnostic and Statistical Manual of Mental Disorders IV criteria in the post-anaesthesia care unit (PACU) as well as within the first week after surgery. Cognitive function was assessed with a neuropsychological test battery. Multivariable analysis of POCD was performed with consideration of predisposing and precipitating factors.

RESULTS

Of 1277 randomized patients, 850 (66.6%) had complete data. Delirium was found in 270 patients (32.9% of 850). We detected POCD in 162 (20.9% of 776) at 1 week and in 52 (9.4% of 553) at 3 months. In multivariable analysis (n = 808), delirium had no overall effect on POCD (P = 0.30). Patients with no delirium in PACU but with postoperative delirium within 7 days had an increased risk of POCD at 3 months (OR = 2.56 (95%-confidence interval: 1.07-6.16), P = 0.035). No significant association was found for the other subgroups.

CONCLUSIONS

There is no clear evidence that postoperative delirium is independently associated with POCD up to 3 months.

Risk factors of post-operative delirium after elective vascular surgery in the elderly: A systematic review

BACKGROUND

Postoperative delirium is a common and serious adverse event in the elderly patient and is associated with significant morbidity and mortality. It is of great importance to identify patients at risk for delirium, in order to focus preventive strategies. The aim of this article is to systematically review current available literature on pre-operative risk factors for delirium after vascular surgery.

METHODS

A systematic literature search was conducted using PubMed and EMBASE, using the MeSH terms and key words "delirium", "surgery" and "risk factor". Studies were retained for review after meeting strict inclusion criteria that included only prospective studies evaluating risk factors for delirium in patients who had elective vascular surgery. Diagnosis of delirium needed to be confirmed using the Diagnostic and Statistical Manual of Mental Disorders (DSM) or ICD-10.

RESULTS

Fifteen articles were selected for inclusion, incidence of delirium across the studies ranged from 5% to 39%. Many factors have been associated with increased risk of delirium, including age, cognitive impairment, comorbidity, depression, smoking, alcohol, visual and hearing impairment, ASA-score, biochemical abnormalities, operative strategies and blood loss.

CONCLUSIONS

Delirium is a common complication after elective vascular surgery in elderly. The highest delirium incidence was observed after open aortic surgery as well as after surgery for critical limb ischemia. A picture starts to form of which predisposing factors lead to increased risk of delirium. The leading risk factors consistently identified in this systematic review were advanced age and cognitive impairment. Multi-disciplinary specialist-led interventions in the preoperative phase could decrease incidence and severity of delirium and should be focused on identified high-risk patients.

Association of pre-operative medication use with post-operative delirium in surgical oncology patients receiving comprehensive geriatric assessment

BACKGROUND

Older patients undergoing surgery tend to have a higher frequency of delirium. Delirium is strongly associated with poor surgical outcomes. This study evaluated the association between pre-operative medication use and post-operative delirium (POD) in surgical oncology patients receiving comprehensive geriatric assessment (CGA).

METHODS

A total of 475 patients who were scheduled for cancer surgery and received CGA from January 2014 to June 2015 were included. Pre-operative medication review through CGA was conducted on polypharmacy (≥5 medications), delirium-inducing medications (DIMs), fall-inducing medications (FIMs), and potentially inappropriate medications (PIMs). POD was confirmed by psychiatric consultation, and DSM-V criteria were used for diagnosing delirium. The model fit of the prediction model was assessed by computing the Hosmer-Lemeshow goodness-of-fit test. Effect size was measured using the Nagelkerke R(2). Discrimination of the model was assessed by an analysis of the area under receiver operating curve (AUROC).

RESULTS

Two models were constructed for multivariate analysis based on univariate analysis; model I included dementia and DIM in addition to age and sex, and model II included PIM instead of DIM of model I. Every one year increase of age increased the risk of POD by about 1.1-fold. DIM was a significant factor for POD after adjusting for confounders (AOR 12.78, 95 % CI 2.83-57.74). PIM was also a significant factor for POD (AOR 5.53, 95 % CI 2.03-15.05). The Hosmer-Lemeshow test results revealed good fits for both models (χ(2) = 3.842, p = 0.871 for model I and χ(2) = 8.130, p = 0.421 for model II). The Nagelkerke R(2) effect size and AUROC for model I was 0.215 and 0.833, respectively. Model II had the Nagelkerke R(2)effect size of 0.174 and AUROC of 0.819.

CONCLUSIONS

These results suggest that pharmacists' comprehensive review for pre-operative medication use is critical for the post-operative outcomes like delirium in older patients.

Fried frailty phenotype assessment components as applied to geriatric inpatients

BACKGROUND

Management of geriatric patients would be simplified if a universally accepted definition of frailty for clinical use was defined. Among definitions of frailty, Fried frailty phenotype criteria constitute a common reference frame for many geriatric studies. However, this reference frame has been tested primarily in elderly patients presenting with relatively good health status.

OBJECTIVE

The aim of this article was to assess the usefulness and limitations of Fried frailty phenotype criteria in geriatric inpatients, characterized by comorbidity and functional impairments, and to estimate the frailty phenotype prevalence in this group.

PATIENTS AND METHODS

Five hundred consecutive patients of the university hospital subacute geriatric ward, aged 79.0±8.4 years (67% women and 33% men), participated in this cross-sectional study. Comprehensive geriatric assessment and Fried frailty phenotype component evaluation were performed in all patients.

RESULTS

Multimorbidity (6.0±2.8 diseases) characterized our study group, with a wide range of clinical conditions and functional states (Barthel Index of Activities of Daily Living 72.2±28.2 and Mini-Mental State Examination 23.6±7.1 scores). All five Fried frailty components were assessed in 65% of patients (95% confidence interval [CI] =60.8-69.2) (diagnostic group). One or more components were not feasible to be assessed in 35% of the remaining patients (nondiagnostic group) because of lack of past patient's body mass control and/or cognitive or physical impairment. Patients from the nondiagnostic group, as compared to patients from the diagnostic group, presented with more advanced age, higher prevalence of dementia, lower prevalence of hypertension, lower systolic and diastolic blood pressure, body mass index, Mini-Mental State Examination and Barthel Index of Activities of Daily Living. Despite diagnostic limitations, we found ≥3 positive criteria (thus, frailty diagnosis) in 54.2% of the study group (95% CI =49.8-58.6), with prevalence from 31.7% in sexagenarians to 67.6% in nonagenarians.

CONCLUSION

Fried frailty phenotype criteria seem useful for geriatric inpatient assessment, despite diagnostic limitations. High prevalence of frailty among geriatric inpatients suggests that evaluation for frailty should be considered a part of the comprehensive geriatric assessment.

Depressive Symptoms and Risk of Postoperative Delirium

OBJECTIVE

Previous studies have shown that elevated depressive symptoms are associated with increased risk of postoperative delirium. However, to our knowledge no previous studies have examined whether different components of depression are differentially predictive of postoperative delirium.

METHODS

One thousand twenty patients were screened for postoperative delirium using the Confusion Assessment Method and through retrospective chart review. Patients underwent cognitive, psychosocial, and medical assessments preoperatively. Depression was assessed using the Geriatric Depression Scale-Short Form.

RESULTS

Thirty-eight patients developed delirium (3.7%). Using a factor structure previously validated among geriatric medical patients, the authors examined three components of depression as predictors of postoperative delirium: negative affect, cognitive distress, and behavioral inactivity. In multivariate analyses controlling for age, education, comorbidities, and cognitive function, the authors found that greater behavioral inactivity was associated with increased risk of delirium (OR: 1.95 [1.11, 3.42]), whereas negative affect (OR: 0.65 [0.31, 1.36]) and cognitive distress (OR: 0.95 [0.63, 1.43]) were not.

CONCLUSION

Different components of depression are differentially predictive of postoperative delirium among adults undergoing noncardiac surgery.

Prevalence and risk factors of postoperative delirium in elderly hip fracture patients

Objective

To explore the risk factors associated with postoperative delirium (PD) in elderly patients following total hip arthroplasty (THA) for hip fracture.

Methods

This prospective study enrolled elderly patients (≥ 65 years) with hip fractures who underwent THA under general anaesthesia, and who had a complete set of postoperative observations. Detailed medical history and perioperative characteristics were recorded. During the postoperative period, patients were assessed twice daily for PD using the Confusion Assessment Method.

Results

A total of 572 patients were eligible for inclusion in the study. Of these, 120 patients (21.0%) were diagnosed with PD and 452 patients (79.0%) did not experience PD. Multivariate stepwise logistic regression analyses showed that older age, a history of stroke, lower albumin, higher blood glucose, higher total bilirubin, higher C-reactive protein, longer surgery duration and higher volume of red blood cell transfusions were independent risk factors for PD.

Conclusions

Correcting the modifiable risk factors might help prevent PD. Strategies might include nutritional support, tight blood glucose control, improvement of liver function, preoperative infection control and minimizing surgical injury or blood loss.