Risk Of Postoperative Cognitive Decline Research Articles

98 Cognitive Outcomes Following Bilateral Focused Ultrasound Thalamotomy for Tremor

Objective:Essential tremor (ET) is the most common movement disorder, characterized by bilateral action tremors of the upper extremities. Surgical interventions can be considered for severe cases that are refractory to medication. Magnetic resonance-guided focused ultrasound (MRgFUS) of the ventral intermediate nucleus of the thalamus (Vim) is a recently approved, minimally invasive treatment for unilateral tremor. While patients are generally pleased with unilateral treatment, many patients are bothered by tremor on the untreated side. Historically, bilateral thalamotomy has been associated with a higher rate of adverse events, including cognitive impairment. MRgFUS Vim thalamotomy for bilateral tremor is currently being investigated. The goal of the present study was to evaluate the effect of bilateral MRgFUS Vim thalamotomy on cognition.Participants and Methods:Twelve patients with medication-refractory essential tremor (mean age = 68.77 +/- 11.78 years, mean education = 14.34 +/- 2.71 years, 8 male) were included in the present study. Three of the 12 patients met criteria for mild cognitive impairment (MCI). All patients successfully underwent unilateral MRgFUS thalamotomy at least 48 weeks before the second thalamotomy. A battery of neuropsychological tests was administered to patients before (considered baseline in the present study) and three months following the second thalamotomy. Baseline evaluations occurred on average 144.64 +/- 91.53 weeks (range: 55.00 - 346.58) after the first thalamotomy. The neuropsychological battery assessed domains of processing speed (Oral Symbol Digit Modalities Test, D-KEFS Color-Word Naming and Reading), attention (WAIS-IV Digit Span Forward), executive function (D-KEFS Color-Word Inhibition and Inhibition/Switching), working memory (WAIS-IV Digit Span Backward and Sequencing), verbal fluency (D-KEFS Letter Fluency and Animal Fluency), confrontation naming (Boston Naming Test), verbal memory (Hopkins Verbal Learning Test-Revised), and visuospatial perception (Judgment of Line Orientation). Alternate versions of tests were used when possible. Cognitive changes were analyzed at the group and individual level. Group level changes were assessed with paired sample t-tests (corrected for multiple comparisons). At the individual level, postoperative declines > 1.5 SD from baseline were considered clinically significant.Results:Participants’ baseline intellectual functioning ranged from low average to superior (as measured by the WTAR). The mean baseline score on the Montreal Cognitive Assessment was 24.58 (range: 17 - 30). At the group level, there were no significant changes in cognitive scores from baseline to follow-up (all p values > 0.635). At the individual level, one patient with MCI declined > 1.5 SD on the verbal memory composite. No other patients showed declines > 1.5 SD.Conclusions:Our preliminary findings suggest that bilateral MRgFUS Vim thalamotomy is relatively safe from a cognitive perspective. However, a single patient with MCI exhibited clinically significant postoperative decline in verbal memory. Future studies with larger sample sizes are needed to investigate the factors that increase the risk of postoperative cognitive decline, including pre-existing cognitive impairment, older age, and lesion size.

Effects of nurse-led home-based telephone support or home visits on cognitive function.

Patients who have undergone carotid revascularization surgery have a high risk of postoperative cognitive decline, and home‐based care is the major form of postoperative management. Here, we aimed to compare the nurse‐led home‐based telephone support (NLHBTS) and home visits as additional postoperative care for patients who have undergone carotid revascularization surgery. The study recruited 172 patients, and 131 patients were randomly assigned to receive combined telephone support and home visits (intervention group) or home visits alone (control group) during the study period of 12 weeks. At baseline, 1 month, and 3 months, cognitive function was assessed using the Trail Making Test, Processing Speed Index, Boston Naming Test, Working Memory Index, Controlled Oral Word Association Test, and Hopkins Verbal Test. Sixty‐five patients in the intervention group and 66 in the control group completed the 1‐month treatment, and 49 in the intervention group and 48 in the control group completed the 3‐month treatment. The intervention group showed significant improvement in four of the six cognitive tests after the 3‐month treatment, whereas the control group only showed significant improvement in the Controlled Oral Word Association Test. Compared to the control group, significantly higher scores were achieved by the intervention group at 3 months in the Trail Making Tests (113 ± 23 vs. 128 ± 18, p = 0.001), Processing Speed Index (115 ± 15 vs. 108 ± 14, p = 0.020), Controlled Oral Word Association Test (51 ± 11 vs. 45 ± 9, p = 0.004), and Hopkins Verbal Learning Test (9.0 ± 1.6 vs. 8.3 ± 1.8, p = 0.046). NLHBTS, in combination with home visits, could facilitate the improvement of cognitive function in patients with carotid artery stenosis after surgery.

Cognitive impairment assessment and interventions to optimize surgical patient outcomes.

For elderly patients undergoing elective surgical procedures, preoperative evaluation of cognition is often overlooked. Patients may experience postoperative delirium (POD) and postoperative cognitive decline (POCD), especially those with certain risk factors, including advanced age. Preoperative cognitive impairment is a leading risk factor for both POD and POCD, and studies have noted that identifying these deficiencies is critical during the preoperative period so that appropriate preventive strategies can be implemented. Comprehensive geriatric assessment is a useful approach which evaluates a patient's medical, psycho-social, and functional domains objectively. Various screening tools are available for preoperatively identifying patients with cognitive impairment. The Enhanced Recovery After Surgery (ERAS) protocols have been discussed in the context of prehabilitation as an effort to optimize a patient's physical status prior to surgery and decrease the risk of POD and POCD. Evidence-based protocols are warranted to standardize care in efforts to effectively meet the needs of these patients.

The impact of cerebrovascular risk factors on postoperative memory decline in patients with left temporal lobe epilepsy

Cerebrovascular risk factors (CVRFs) and comorbid cardiovascular and metabolic disease have been linked to accelerated cognitive aging and dementia in the general population; however, the contribution of these comorbidities to the risk of post anterior temporal lobectomy (ATL) memory decline has been unexamined. We explored the effects of CVRFs on postoperative verbal memory decline in a cohort of 22 patients with left temporal lobe epilepsy (LTLE) who completed pre- and one-year postsurgical neuropsychological testing. Diagnoses of interest included preoperative cardiovascular and metabolic disorders, as well as CVRFs [pulse pressure proxy, body mass index (BMI), and fasting glucose]. Twenty-three percent of patients had a history of cardiovascular disease, 9% of metabolic disorders, and 38% had a BMI indicating overweight or obese status. Higher preoperative BMI and glucose were associated with greater decline in verbal memory. The association between BMI and memory decline remained significant after controlling for age and left hippocampal volume. These findings suggest that modifiable health-related risk factors, including CVRFs, may impact the risk of postoperative cognitive decline, and that BMI in particular could be an important factor to consider and/or target for intervention early in clinical care to protect cognitive health.

Longitudinal Changes in Regional Cerebral Perfusion and Cognition After Cardiac Operation

Cardiac operation has been associated with increased risk of postoperative cognitive decline, as well as dementia risk in the general population. Few studies, however, have examined the impact of coronary revascularization or valve replacement or repair operation on longitudinal cerebral perfusion changes or their association with cognitive function. We examined longitudinal changes in cerebral perfusion among 54 individuals with cardiac disease; 27 undergoing cardiac operation and 27 matched control patients. Arterial spin labeling magnetic resonance perfusion imaging was used to quantify cerebral blood flow within the anterior communicating artery, middle cerebral artery (MCA), and posterior communicating artery vascular territories before operation and postoperatively at 6 weeks and 1 year. Cognitive performance was examined during the same intervals by using a battery of tests that tapped memory, executive, information processing and upper extremity motor functions. Repeated measures, mixed models were used to examine for perfusion changes and theassociation between perfusion changes and cognition. Significant postoperative increases in perfusion were observed at 6 weeks within the MCA vascular territory after cardiac operation (p= 0.035 for interaction). Perfusion changes were most notable in distal territories of the MCA and posterior communicating artery at 6 weeks, with no additional changes at 1 year. Postoperative increases in MCA perfusion at 6 weeks were associated with improved psychomotor speed (β= 0.35, p= 0.016), whereas no important differences were found between the groups in vascular territory perfusion and cognition at 1 year. Cardiac operation is associated with important short-term increases in MCA perfusion with associated improvements in psychomotor speed.

The Beneficial Effects of Cognitive Training With Simple Calculation and Reading Aloud (SCRA) in the Elderly Postoperative Population: A Pilot Randomized Controlled Trial.

Background: There has been little research conducted regarding cognitive treatments for the elderly postsurgical population. Patients aged ≥60 years have an increased risk of postoperative cognitive decline, a condition in which cognitive functions are negatively affected. This cognitive decline can lead to a decline in quality of life. In order to maintain a high quality of life, the elderly postsurgical population may benefit from treatment to maintain and/or improve their cognitive functions. This pilot study investigates the effect of simple calculation and reading aloud (SCRA) cognitive training in elderly Japanese postsurgical patients.Methods: Elderly patients undergoing non-cardiovascular thoracic surgery under general anesthesia were recruited (n = 12). Subjects were randomly divided into two groups—one that receives 12 weeks of SCRA intervention, and a waitlisted control group. Before and after the intervention, we measured cognitive function [Mini-Mental Status Exam-Japanese (MMSE-J), Frontal Assessment Battery (FAB), computerized Cogstate Brief Battery (CBB)] and emotional state [General Health Questionnaire-12 (GHQ-12), Geriatric Depression Scale (GDS), Quality of Life Scale-5 (QOL-5)].Results: Group difference analyses using ANCOVA with permutation test showed that the intervention SCRA group had a significant improvement in FAB motor programming sub-score, GDS, and QOL-5 compared to the control group. Within-group analyses using Wilcoxon signed-rank test to compare baseline and follow-up showed that the SCRA intervention group total FAB scores, FAB motor programming sub-scores, and QOL-5 scores were significantly improved.Discussion: This pilot study showed that there are important implications for the beneficial effects of SCRA intervention on cognitive function and emotional state in the postoperative elderly population; however, further investigations are necessary to reach any conclusions.Trial registration: This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trial Registry (UMIN000019832).

Indication of Cognitive Change and Associated Risk Factor after Thoracic Surgery in the Elderly: A Pilot Study.

Background: This pilot study investigated the effects of partial pulmonary lobectomy lung surgery on cognitive functions of elderly Japanese patients. It is recognized that elderly patients undergoing surgery have increased risk of Postoperative Cognitive Decline (POCD), a condition in which learning, memory, and processing speed is greatly reduced after surgery. Since elderly patients are more likely to exhibit symptoms of POCD, the incidence is increasing as the population receiving surgery is aging.Methods: Cognitive function was measured for all subjects (n = 12) before and after surgery using three different cognitive tests: Mini-Mental Status Exam-Japanese (MMSE-J), Frontal Assessment Battery (FAB), and a computerized Cogstate Brief Battery (CBB). Changes in these measures indicate changes in cognitive function. In addition, the 12-item General Health Questionnaire (GHQ-12), the Geriatric Depression Scale (GDS), and the 5-item Quality of Life questionnaire (QOL-5) were administered at each time point to measure mental and emotional state. Changes in outcome measures were analyzed via Wilcoxon signed-rank test. Exploratory correlation analysis was conducted using Spearman’s rho.Results: Data show a decline in detection (DET; p = 0.045) and identification (IDN; p = 0.038). Spearman’s correlation coefficient show a significant correlation between postoperative DET scores and postoperative IDN scores (ρ = 0.78, p = 0.005), a significant correlation between change in IDN and baseline GHQ-12 scores (ρ = -0.595, p = 0.027), and a significant correlation between change in one-back (OBK) scores and duration of anesthesia (ρ = -0.72, p = 0.012).Discussion: This was the first report to examine cognitive decline after major thoracic surgery in Japanese patients. Previous studies have evidenced that POCD is a common phenomenon after surgery, and that age is a major risk factor. The CCB measured significant change in two cognitive domains: attention and psycomotor function. This study clarified that decline in cognition is detectable in certain measures after thoracic surgery in the elderly Japanese patient population. Additionally, longer anesthetic exposure may negatively impact attention and working memory, and preoperative mental wellbeing is a possible predictor of POCD. These preliminary results have important implications and support the need for future studies.

Effects of dexamethasone on early cognitive decline after cardiac surgery: A randomised controlled trial.

Postoperative cognitive decline (POCD), a very common complication after cardiac surgery, is characterised by impairment of both memory function and intellectual ability as well as being associated with increased use of healthcare resources. The investigators focused on the role of the inflammatory response to a surgical procedure as a potential factor involved in the pathogenesis of POCD. The use of prophylactic dexamethasone to attenuate the inflammatory response was hypothesised to reduce the risk of POCD. Randomised controlled study. Single university teaching hospital, from March 2015 to January 2016. A total of 169 patients scheduled for elective cardiac surgery were enrolled, and 161 patients were included in the analyses. Patients were randomised to receive a single intravenous bolus of 0.1 mg kg dexamethasone (n = 85) or placebo (n = 84) 10 h before the surgery. The primary outcome measure in both groups was the incidence of POCD on the 6th day after surgery. The investigators also evaluated the effect of dexamethasone on the incidence of systemic inflammatory response syndrome, postoperative C-reactive protein levels and postoperative serum S100β protein levels. Compared to the placebo group, the dexamethasone group showed statistically significant reductions in the incidence of POCD (relative risk, 0.43; 95% confidence interval, 0.21 to 0.89; P = 0.02), the incidence of systemic inflammatory response syndrome (30.0 versus 58.0%, P < 0.001) and postoperative C-reactive protein levels (P < 0.001). Postoperative S100β levels were insignificantly lower (P = 0.56) in the dexamethasone group. Preoperative administration of dexamethasone reduced the inflammatory response and thereby decreased the risk of early POCD after cardiac surgery. Clinicaltrials.gov identifier: NCT02767713.

The beneficial effects of cognitive training with simple calculation and reading aloud in an elderly postsurgical population: study protocol for a randomized controlled trial.

BackgroundThis project proposes a pilot study to investigate the positive healing effects of cognitive training with simple arithmetic and reading aloud on elderly postsurgical patients. Elderly patients undergoing surgery have an increased risk of Postoperative Cognitive Decline (POCD), a condition in which learning, memory, and processing speed is greatly reduced after surgery. Since elderly patients are more likely to exhibit symptoms of POCD, the incidence is increasing as the population receiving surgery has aged. Little effort has been expended, however, to find treatments for POCD. Learning therapy, which consists of a combination of reading aloud and solving simple arithmetic problems, was developed in Japan as a treatment for Alzheimer’s Disease to improve cognitive functions. Because patients with Alzheimer’s Disease experience similar issues as those with POCD in learning, memory, and processing speed, a cognitive intervention based on the learning-therapy treatments used for Alzheimer’s Disease could show advantageous outcomes for those at risk of POCD.Methods/designCognitive function will be measured before and after surgery using three different tests (Mini-Mental Status Exam, Frontal Assessment Battery, and Cogstate computerized tests). Subjects will be randomly divided into two groups—one that receives a Simple Calculation and Reading Aloud intervention (SCRA) and a waitlisted control group that does not receive SCRA. To measure cognition before and after the intervention, the previously mentioned three tests will be used. The obtained data will be analyzed using statistical tests such as ANCOVA to indicate whether the cognitive intervention group has made improvements in their cognitive functions. In addition, questionnaires will also be administered to collect data on mental and emotional statuses.DiscussionThis report will be the first pilot study to investigate the beneficial effects of SCRA on elderly surgical patients. Previous studies have shown sufficient evidence on the effectiveness of learning therapy in healthy elderly people and in those with Dementia. Therefore, this study will clarify whether SCRA can improve cognitive function in the more specialized group of elderly surgical patients.Trial registrationUniversity Hospital Medical Information Network Clinical Trial Registry, UMIN000019832. Registered on 18 November 2015.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-016-1476-0) contains supplementary material, which is available to authorized users.

Effects of Dexamethasone on Cognitive Decline After Cardiac Surgery

Ottens, Thomas H.*; Dieleman, Jan M.*; Sauër, Anne-Mette C.*; Peelen, Linda M.†; Nierich, Arno P.‡; De Groot, Welmer J.§; Nathoe, Hendrik M.∥; Buijsrogge, Marc P.¶; Kalkman, Cor J.*; Van Dijk, Diederik# for the Dexamethasone for Cardiac Surgery (DECS) Study Group Author Information

Early Cognitive Decline In Pituitary Surgery: Is Nitrous Oxide the Culprit?

ABSTRACT Aim: Pituitary tumors have been found to produce cognitive dysfunctions predominantly related to memory and attention. There exists a potential interaction between surgical and anesthetic factors in producing cognitive changes. Therefore we aim to investigate the incidence of cognitive decline and role of nitrous oxide (N2O) on immediate cognitive changes in patients undergoing transsphenoidal removal of pituitary tumors. Patients &amp; methods: Ninety patients between 18 and 65 years of age, undergoing transsphenoidal surgery for pituitary tumor removal, were enrolled and divided into two (air and N2O-based anesthetic regime) groups. Cognitive functions were noted using the Hindi Mini Mental State Examination at baseline and three times in the postoperative period (1-h, 24-h postextubation and at the time of hospital discharge). Results: Both groups were comparable with respect to demographics, baseline parameters and cognitive scores. Significant number of patients (73%) showed cognitive decline in both the groups within 24 h postoperatively. In the factor analysis, thyroid-stimulating hormone and fentanyl consumption were linked with changes in cognitive scores. Conclusion: Patients undergoing pituitary surgery have significantly immediate cognitive decline in the short followup, but N2O-based anesthesia alone does not increase the risk of postoperative cognitive decline.

Effects of dexamethasone on cognitive decline after cardiac surgery: a randomized clinical trial.

Cardiac surgery can be complicated by postoperative cognitive decline (POCD), which is characterized by impaired memory function and intellectual ability. The systemic inflammatory response that is induced by major surgery and cardiopulmonary bypass may play an important role in the etiology of POCD. Prophylactic corticosteroids to attenuate the inflammatory response may therefore reduce the risk of POCD. The authors investigated the effect of intraoperative high-dose dexamethasone on the incidence of POCD at 1 month and 12 months after cardiac surgery. This multicenter, randomized, double-blind, placebo-controlled trial is a preplanned substudy of the DExamethasone for Cardiac Surgery trial. A total of 291 adult patients undergoing cardiac surgery with cardiopulmonary bypass were recruited in three hospitals and randomized to receive dexamethasone 1 mg/kg (n = 145) or placebo (n = 146). The main outcome measures were incidence of POCD at 1- and 12-month follow-up, defined as a decline in neuropsychological test performance beyond natural variability, as measured in a control group. At 1-month follow-up, 19 of 140 patients in the dexamethasone group (13.6%) and 10 of 138 patients in the placebo group (7.2%) fulfilled the diagnostic criteria for POCD (relative risk, 1.87; 95% CI, 0.90 to 3.88; P = 0.09). At 12-month follow-up, 8 of 115 patients in the dexamethasone group (7.0%) and 4 of 114 patients (3.5%) in the placebo group had POCD (relative risk, 1.98; 95% CI, 0.61 to 6.40; P = 0.24). Intraoperative high-dose dexamethasone did not reduce the risk of POCD after cardiac surgery.

Preoperative Cerebral Hypoperfusion in the Left, Not in the Right, Hemisphere Is Associated With Cognitive Decline After Cardiac Surgery

Postoperative cognitive decline (POCD) is a frequent complication after cardiac surgery. Although intraoperative events are risk factors for POCD, the role played by preoperative hypoperfusion in cognitive decline has not yet been investigated. It is also unknown whether the impact of preoperative hypoperfusion in the left or right middle cerebral arteries (MCAs) can differentially account for POCD. The main aims of this study were to investigate whether preoperative cerebral hypoperfusion was associated with early POCD and whether lateralized hypoperfusion would differentially affect POCD in patients after cardiac surgery. Bilateral MCA continuous transcranial Doppler (TCD) sonography was preoperatively performed at rest in 31 right-handed patients who underwent cardiac surgery to detect cerebral blood flow (CBF) velocity. All patients completed a neuropsychological evaluation to assess attention, short-term memory, working memory, and psychomotor function before surgery and at discharge. POCD was defined using the standard deviation method. Logistic regression was used to investigate the association between hypoperfusion and POCD, controlling for common preoperative risk factors. Fourteen patients (45%) exhibited POCD. Cerebral hypoperfusion in the left MCA selectively predicted the incidence of POCD (odds ratio = 0.90, p < .02), whereas CBF velocity in the right MCA was unrelated to POCD (odds ratio = 1.07, p = .39). Patients who underwent cardiac surgery with reduced CBF velocity in the left MCA preoperatively are at greater risk for POCD. Left cerebral hypoperfusion may also represent an independent predictor of POCD in these patients. TCD evaluation may have substantial clinical benefits for the detection of patients at high risk of POCD after cardiac surgery.

The (Un)Importance of Cerebral Microemboli

The use of cardiopulmonary bypass (CPB) is associated with cerebral microemboli. Cognitive decline after cardiac surgery has therefore always been attributed to the use of CPB. However, randomized studies comparing coronary bypass surgery with and without CPB failed to establish a clear cognitive benefit of avoiding CPB. The aim of this analysis was to systematically review the studies that directly assessed the association between cerebral microemboli and cognitive decline after cardiac surgery. The electronic database of PubMed of the National Library of Medicine from 1980 until 2009 was searched to identify relevant literature. Search terms related to "cardiac surgery," "microemboli," and "cognitive decline" were used. Studies were reviewed independently by 2 reviewers and relevant articles were included completely if they matched the selection criteria. This review included studies in adult cardiac surgical patients reporting both a measure of cerebral embolic load and cognitive outcomes. The literature search yielded 423 different titles, of which 22 met the selection criteria. All 22 studies used neuropsychological tests to determine cognitive outcome. Seven studies used postoperative (diffusion-weighted) magnetic resonance imaging (MRI) to detect cerebral emboli and 15 studies used intraoperative transcranial Doppler imaging. In 1 MRI study and 5 Doppler studies, an association was found between the number of cerebral emboli and the risk of postoperative cognitive decline. In 15 studies, such an association could not be established. One study did not assess the direct relation between microemboli and cognitive decline. This systematic review could neither confirm nor rule out a causal link between emboli from CPB and postoperative cognitive decline.

Postoperative cognitive decline

Memory loss and lack of concentration are symptoms that frequently occur in patients who have undergone a surgical procedure. Although cognitive function can be assessed using neuropsychological tests, reliable diagnosis of postoperative cognitive decline (POCD) appears to be difficult. Therefore, the true incidence of POCD is unknown. Severe POCD, which is apparent even without neuropsychological testing, is reported most frequently after cardiac and hip-replacement surgery. In these cases, POCD probably reflects microembolic brain injury. Apart from the nature of the surgical procedure, advanced age is the most important risk factor for POCD. The anesthetic technique is not a determinant of POCD: the risk of POCD appears to be similar after both general and regional anesthesia.

Neuropsychologic assessment of patients for movement disorder surgery.

The neuropsychologic evaluation of patients under consideration for movement disorder surgery is recognized as being an essential component of the preoperative process. Patients with early-stage concomitant dementia must be identified and the relative risk of postoperative cognitive decline evaluated. Knowledge of the patterns of an individual's strengths and weaknesses might also be a factor in deciding on a neurosurgical procedure. Although the advent of pallidal deep brain stimulation (DBS) has possibly resulted in reduced risk of induced cognitive impairment, even this procedure has been associated with negative sequelae. DBS within the subthalamic nucleus is becoming the method of choice and this may lead to cognitive and behavioral compromise, especially in the elderly patient. The team considering the establishment of neurosurgical treatment is often at a loss to decide how much neuropsychologic testing is required to determine relative risks of cognitive or behavioral morbidity as a consequence of the procedure. A brief summary of expected outcome and of pertinent family process and psychodynamic issues are addressed. This article is intended to serve as a guide to permit clinicians to choose the appropriate length and depth of neuropsychologic assessment, but also to highlight the confounding factors often present in these patients.