Postoperative Cognitive Disorders Research Articles

The Role of the Glymphatic System in Perioperative Neurocognitive Disorders.

The glymphatic system plays a crucial role in clearing metabolic waste from the central nervous system and is most active during sleep. Patients with obstructive sleep apnea (OSA) have a dysfunctional glymphatic system that correlates with disease severity. In addition, these patients have worse outcomes after surgery. The status of the glymphatic system during the perioperative period is unclear and can be examined with magnetic resonance imaging (MRI)-based diffusion tensor imaging (DTI). This study assessed perioperative glymphatic system changes in OSA surgical patients and possible relationships with perioperative neurocognitive disorders. DTI data from 13 OSA patients having laparoscopic abdominal surgery with general anesthesia were acquired and analyzed using a 3.0-T MRI scanner. Diffusivity maps in the x-axis (Dxx), y-axis (Dyy), z-axis (Dzz), x-y axis (Dxy), y-z axis (Dyz), and x-z axis (Dxz) were calculated. Diffusion values for the projection and association fibers were extracted, and DTI analysis along the perivascular space (ALPS) was performed. The patients' cognition was assessed using the Montreal Cognitive Assessment tool. Evaluations were carried out within 5 days before surgery and within the first 48 hours after surgery. The ALPS index decreased after surgery, and this correlated with a decrease in general cognition scores and specific memory domains, including visuospatial and delayed recall. The glymphatic system in OSA patients is worsened after surgery and this may contribute to an increased risk for long-term postoperative cognitive disorders. This study suggest that the glymphatic system might play a role in the pathophysiology of perioperative neurocognitive disorders and be a potential therapeutic target.

Prognostic significance of predictors of early postoperative cognitive disorders in patients after traumatic surgeries (prospective cohort study)

Prognostic significance of predictors of early postoperative cognitive disorders in patients after traumatic surgeries (prospective cohort study)

Postoperative cognitive disorders and delirium in gynecologic surgery: Which surgery and anesthetic techniques to use to reduce the risk?

Despite their general good health, an increasing proportion of elderly individuals require surgery due to an increase in average lifespan. However, because of their increased vulnerability, these patients need to be handled carefully to make sure that surgery does not cause more harm than good. Age-related postoperative cognitive disorders (POCD) and postoperative delirium (POD), two serious consequences that are marked by adverse neuropsychologic alterations after surgery, are particularly dangerous for the elderly. In the context of gynecologic procedures, POCD and POD are examined in this narrative review. The main question is how to limit the rates of POCD and POD in older women undergoing gynecologic procedures by maximizing the risk-benefit balance. Three crucial endpoints are considered: (1) surgical procedures to lower the rates of POCD and POD, (2) anesthetic techniques to lessen the occurrence and (3) the identification of individuals at high risk for post-surgery cognitive impairments. Risks associated with laparoscopic gynecologic procedures include the Trendelenburg posture and CO2 exposure during pneumoperitoneum, despite statistical similarities in POD and POCD frequency between laparoscopic and laparotomy techniques. Numerous risk factors are associated with surgical interventions, such as blood loss, length of operation, and position holding, all of which reduce the chance of complications when they are minimized. In order to emphasize the essential role that anesthesia and surgery play in patient care, anesthesiologists are vital in making sure that anesthesia is given as sparingly and quickly as feasible. In addition, people who are genetically predisposed to POCD may be more susceptible to the disorder. The significance of a thorough strategy combining surgical and anesthetic concerns is highlighted in this article, in order to maximize results for senior patients having gynecologic surgery.

Possibilities of using regional anesthesia with diode-laser transscleral cyclophotocoagulation in children: description of clinical cases

BACKGROUND: Diode-laser transscleral cyclophotocoagulation (DLTCPC) is one of the most commonly used treatment options for intraocular pressure reduction in refractory glaucoma in adult and pediatric patients. To achieve the necessary effect, these operations often have to be repeated. Repeated general anesthesia inductions increase the risk of cognitive disorders in children and sometimes do not provide sufficient postoperative analgesia.
 OBJECTIVE: To analyze the results of transscleral DLTCPC in children under regional anesthesia and identify factors predisposing to the choice of this anesthesia method.
 MATERIALS AND METHODS: The study included 33 children aged 1017 years who had undergone 57 transscleral DLTCPCs in IRTC Eye Microsurgery Ekaterinburg Center between 01.09.2017 to 31.08.2022. In each case, the anesthesia method was selected individually according to the principle of reasonable sufficiency.
 RESULTS: Of 57 operations, 36 (73%) were performed under regional and 21 (37%) were under general anesthesia. Factors that favor regional anesthesia include (1) psycho-emotional maturity of the patient, (2) older age, and (3) greater number of previous operations. An algorithm for the selection of the anesthesia method is presented, as well as a plan for the conversation with the patient and his / her legal representatives. Regional anesthesia provides good intra- and postoperative anesthesia and prophylaxis of postoperative cognitive disorders in children who are emotionally stable and suitable for this type of anesthesia.
 CONCLUSION: Considering the psycho-emotional features of children, general anesthesia remains the main method in ophthalmic anesthesiology. Nevertheless, following the principle of reasonable sufficiency and accounting for the short duration of DLTCPC and the large extent of general anesthesia survived by these children previously, regional anesthesia can be successfully used in a portion of these children.

Comment on the Need to Fill a Gap in the Assessment of Neurological Status Before Elective Surgery.

Comment on the Need to Fill a Gap in the Assessment of Neurological Status Before Elective Surgery.

Relationship between Middle Cerebral Artery Pulsatility Index and Delayed Neurocognitive Recovery in Patients undergoing Robot-Assisted Laparoscopic Prostatectomy.

A steep Trendelenburg (ST) position combined with pneumoperitoneum may cause alterations in cerebral blood flow with the possible occurrence of postoperative cognitive disorders. No studies have yet investigated if these alterations may be associated with the occurrence of postoperative cognitive disorders. The aim of the study was to evaluate the association between an increased middle cerebral artery pulsatility index (Pi), measured by transcranial doppler (TCD) 1 h after ST combined with pneumoperitoneum, and delayed neurocognitive recovery (dNCR) in 60 elderly patients undergoing robotic-assisted laparoscopic prostatectomy (RALP). Inclusion criteria were: ≥65 years; ASA class II-III; Mini-Mental Examination score > 23. Exclusion criteria were: neurological or psychiatric pathologies; any conditions that could interfere with test performance; severe hypertension or vascular diseases; alcohol or substance abuse; chronic pain; and an inability to understand Italian. dNCR was evaluated via neuropsychological test battery before and after surgery. Anesthesia protocol and monitoring were standardized. The middle cerebral artery Pi was measured by TCD, through the trans-temporal window and using a 2.5 MHz ultrasound probe at specific time points before and during surgery. In total, 20 patients experiencing dNCR showed a significantly higher Pi after 1 h from ST compared with patients without dNCR (1.10 (1.0-1.19 95% CI) vs. 0.87 (0.80-0.93 95% CI); p = 0.003). These results support a great vulnerability of the cerebral circulation to combined ST and pneumoperitoneum in patients who developed dNCR. TCD could be used as an intraoperative tool to prevent the occurrence of dNCR in patients undergoing RALP.

Incidence and risk factors of cognitive disorders after urologic endoscopic surgery

IntroductionPostoperative cognitive disorders are an emerging public health problem because of its related socio-economic impact.: Postoperative cognitive disorders are an emerging public health problem because of its related socio-economic impact.ObjectivesTo determine the incidence and risk factors of cognitive disorders after endoscopic resection in urology.MethodsThis is an observational, descriptive and analytical study carried out in the urology department of Sahloul University Hospital during a 3 month period, and enrolling patients scheduled for endoscopic resections. Collected data included socio-demographic characteristics and parameters related to the operative management. Cognitive disorders were assessed by the MOCA Test one day before the intervention, then, during the first postoperative day. Patients developing TURP syndrome were excluded.ResultsDuring the study period, 104 patients were enrolled with a mean age of 67.76 years. The sex ratio was 33.6. Main interventions were transurethral resection of bladder tumor and transurethral resection of the prostate.The incidence of cognitive disorders was 45.2% after endoscopic resection. Main Risk factors in multivariate analysis were age (p <10-3), low educational level (p <0.001), sedentary (p <0.001), smoking (p = 0.029), an age gap with spouse> 10 years (p <0.001), high blood pressure (p <0.001), myocardial infarction (p = 0.005); chronic bronchitis (p = 0.002), sleep disorders (p <0.001), preoperative concentration disturbances (p = 0.005), poor quality of patient information (p <0.05), and the type of anesthesia (p = 0.012).ConclusionsThe incidence of cognitive disorders after urologic endoscopic surgery is considerable. Patients with risk factors require preventive measures, regular screening and optimal management.DisclosureNo significant relationships.

The Role of miRNAs in Dexmedetomidine's Neuroprotective Effects against Brain Disorders.

There are limited neuroprotective strategies for various central nervous system conditions in which fast and sustained management is essential. Neuroprotection-based therapeutics have become an intensively researched topic in the neuroscience field, with multiple novel promising agents, from natural products to mesenchymal stem cells, homing peptides, and nanoparticles-mediated agents, all aiming to significantly provide neuroprotection in experimental and clinical studies. Dexmedetomidine (DEX), an α2 agonist commonly used as an anesthetic adjuvant for sedation and as an opioid-sparing medication, stands out in this context due to its well-established neuroprotective effects. Emerging evidence from preclinical and clinical studies suggested that DEX could be used to protect against cerebral ischemia, traumatic brain injury (TBI), spinal cord injury, neurodegenerative diseases, and postoperative cognitive disorders. MicroRNAs (miRNAs) regulate gene expression at a post-transcriptional level, inhibiting the translation of mRNA into functional proteins. In vivo and in vitro studies deciphered brain-related miRNAs and dysregulated miRNA profiles after several brain disorders, including TBI, ischemic stroke, Alzheimer’s disease, and multiple sclerosis, providing emerging new perspectives in neuroprotective therapy by modulating these miRNAs. Experimental studies revealed that some of the neuroprotective effects of DEX are mediated by various miRNAs, counteracting multiple mechanisms in several disease models, such as lipopolysaccharides induced neuroinflammation, β-amyloid induced dysfunction, brain ischemic-reperfusion injury, and anesthesia-induced neurotoxicity models. This review aims to outline the neuroprotective mechanisms of DEX in brain disorders by modulating miRNAs. We address the neuroprotective effects of DEX by targeting miRNAs in modulating ischemic brain injury, ameliorating the neurotoxicity of anesthetics, reducing postoperative cognitive dysfunction, and improving the effects of neurodegenerative diseases.

Postoperative cognitive dysfunction

In recent years, there has been an aging trend throughout the world. Globally, it is estimated that 50% of all older people have had at least one surgical operation. It is well known that compared with younger patients, people over 60 years of age have a higher risk of adverse postoperative outcomes. One of the possible complications of surgical intervention is the development of postoperative cognitive dysfunction (POCD), which is observed in about a quarter of patients. Among gerontological patients and those who underwent cardiac surgery, cognitive impairment is more common, reaching 80%. POCD has a negative impact on the course of recovery processes and life prognosis. There are a large number of risk factors for the development of POCD, associated both with the surgical intervention itself and with the patient's condition. One of the ways to prevent the occurrence of POCD is the use of neurometabolic drugs. Cytoflavin, containing inosine, nicotinamide, riboflavin and succinic acid, has demonstrated its effectiveness in relation to the risk of POCD in cardiac surgery patients. The results of a multicenter, double-blind, placebo-controlled, randomized study confirmed that Cytoflavin is an effective means of preventing and correcting postoperative cognitive disorders in high-risk patients.

Neurophysiological Correlates of Post-Operative Cognitive Disorders

Neurophysiological Correlates of Post-Operative Cognitive Disorders

Результаты оценки когнитивных нарушений в ранний послеоперационный период у кардиохирургических пациентов с артериальной гипертензией, оперированных в условиях искусственного кровообращения

Актуальность. Работа посвящена оценке когнитивных нарушений в ранний послеоперационный период у кардиохирургических пациентов с артериальной гипертензией. Материалы и методы. В исследование вошло 110 пациентов, оперированных в условиях искусственного кровообращения по поводу аортокоронарного шунтирования. Все пациенты были разделены на три группы. В первой группе пациентов проводилась моноанестезия пропофолом, во второй группе — с применением тиопентала, в третьей группе поддержка анестезии проводилась комбинацией пропофола и севофлурана. Для оценки когнитивных нарушений у всех пациентов за 2–3 дня до операции и на 6-й день после оперативного вмешательства использовали нейропсихологическое тестирование: MMSE-тест, FAB-тест, тест рисования часов и SAGE-тест. Результаты. В результате исследования было выявлено, что когнитивные нарушения в ранний послеоперационный период установлены у 61,9 % пациентов первой группы, 48 % пациентов второй группы и 53,48 % пациентов третьей группы. У пациентов второй и третьей группы оказалась достоверно ниже частота дементных когнитивных нарушений по сравнению с первой группой: на 78,58 % (р = 0,0018) и 50 % (р = 0,0021) соответственно. Кроме того, во второй группе достоверно выше частота пациентов без когнитивных нарушений по сравнению с первой группой (р = 0,0032).

Ultrasound-guided Multiple Nerve Blocks: A Safe and Effective Anesthetic Modality in Geriatric Hip Fracture Patients.

The aim was to compare the feasibility of ultrasound-guided multiple nerve blocks (fascia iliaca compartment block+sacral plexus block+superior cluneal nerve block) with general anesthesia in geriatric hip fracture patients. Ninety-four patients were randomly divided into 2 groups: group N received ultrasound-guided multiple nerve blocks and group G received general anesthesia. Primary outcome measures included perioperative Pain Threshold Index (PTI) and Numerical Rating Scale. Secondary outcome measures comprised the following: (1) perioperative Delirium Index and Short Portable Mental Status Questionnaire; (2) perioperative Comfort Index; (3) perioperative opioid consumption (within 72 hours postoperatively); and (4) postoperative side effects (within 72 h postoperatively). Eighty-seven patients completed the study. Baseline PTI was comparable between the groups. However, intraoperative PTI was significantly lower in group N than in group G. Preoperative and postoperative Comfort Index scores were comparable between the groups. Moderate delirium (24 to 72 h postoperatively) was significantly higher than the baseline in group G. Early moderate delirium (24 h postoperatively) was significantly higher in group G than in group N. Severe delirium was comparable between the groups and within each group. High intraoperative PTI was associated with high opioid consumption. The intravenous sufentanil dose in group G was twice of that in group N. Incidence of nausea and vomiting was similar between the groups. Ultrasound-guided multiple nerve blockade may be an alternative to the common anesthetic procedures used for geriatric hip fracture patients. It provided satisfactory intraoperative pain management and reduced early postoperative cognitive disorders.

Neurophysiological Correlates of Postoperative Cognitive Disorders: The Role of Beta Activity

Neurophysiological Correlates of Postoperative Cognitive Disorders: The Role of Beta Activity

Postoperative cognitive dysfunction in patients of the elderly and old age operated for composition of objective cancer

The problem of preserving the quality of life in the postoperative period, one of the criteria of which is the cognitive function, retains its relevance. In patients with advanced and senile age, after undergoing surgery, cognitive disorders are swept aside, which, according to various authors, reaches 64 %. Postoperative cognitive dysfunction was studied in 168 elderly and elderly patients operated on for complications of colon cancer. Patients were divided into two groups. Patients of the control group were operated on operations conventionally, the main one — laparoscopically, using endovideosurgical technologies. Cognitive status was assessed before the operation, as well as on the first, third and seventh days of the postoperative period using the MMSE test (abbr. English Mini Mental State Examination). The incidence of postoperative cognitive dysfunction in both groups was traced. In the development of postoperative cognitive disorders, along with such factors as general anesthesia, age, aggravated neurological history, depressive disorders, operative trauma plays an important role. The use of endoscopic technologies allows reliably reducing the risk of postoperative cognitive impairment, which in turn has a beneficial effect on the postoperative period.

Infuence of anesthesia choice for lower limb joint replacement on progressing early postoperative cognitive disorders in patients of elderlyand senile age

Infuence of anesthesia choice for lower limb joint replacement on progressing early postoperative cognitive disorders in patients of elderlyand senile age

Neurophysiological correlates of postoperative cognitive disorders

A special place among cognitive disorders in patients with cardiovascular diseases is given to postoperative cognitive dysfunction (POCD). The study aimed at investigating the patterns of beta-2 activity associated with postoperative cognitive dysfunction (POCD) in patients after coronary artery bypass grafting (CABG). The study included 60 patients who underwent neuropsychological testing 3-5 days before surgery and on the 7-10th day of CABG. A multichannel electroencephalogram of resting state with eyes closed in 62 standard leads was recorded. Statistical processing of the results was carried out using Statistica 10 (StatSoft Inc, USA) and the developed method of data clustering with a minimax criterion, a software implementation of the binary clipping and branching algorithm was used to find optimal solutions. Patients with POCD had higher pre- and postoperative high-frequency beta-2 rhythm power (20-30 Hz) compared with patients without cognitive impairment. The regression model demonstrated that POCD was associated with high values of preoperative beta-2 activity in the right frontal cortex and with low values in the left parietal areas after CABG. The clustering of beta-2 rhythm power before and after CABG revealed that the best cognitive status corresponded to a stable affiliation of patients with the selected clusters. The specific POCD correlates were established in patients after CABG. Low cognitive status was characterized by the preoperative beta-2 power increase in the right frontal areas and postoperative decrease in the left parietal cortex. The developed method for classifying patients according to the level of pre- and postoperative beta-2 rhythm power has a good discriminant ability. Stable patient affiliation with the selected clusters was associated with a higher level of cognitive status.

Methylene blue reduces incidence of early postoperative cognitive disorders in elderly patients undergoing major non-cardiac surgery: An open–label randomized controlled clinical trial

Study objectiveThe purpose of the present study was to investigate whether methylene blue (MB) could reduce the incidences of postoperative delirium (POD) and early postoperative cognitive dysfunction (POCD) in elderly patients undergoing major non-cardiac surgery. DesignProspective, randomized, open–label clinical trial. SettingUniversity-affiliated hospital. PatientsTwo hundred and forty-eight elderly patients scheduled for non-cardiac surgery. InterventionsElderly patients undergoing non-cardiac major surgery were randomly assigned to MB group (n = 124), who receiving intravenous infusion of 2 mg/kg MB within 60 min immediately after anesthetic induction, or control group (n = 124), who receiving equal volume saline in the same way. MeasurementsAll patients were evaluated with delirium and neuropsychological batteries before and after surgery, as well as perioperative adverse events. Two plasma biomarkers superoxide dismutase (SOD) and homocysteine (HCY) were measured pre- and post-operatively. Main resultsThere were total 39 cases(15.7%)experienced POD. The incidence of POD in MB group was significantly less than that in control group (7.3% vs. 24.2%, OR = 0.24, 95%CI: 0.11–0.53, p < 0.001). The incidence of early POCD at postoperative 7th day in MB group was also less than that in control group (16.1% vs. 40.2%, OR = 0.30, 95% CI: 0.16–0.57, p < 0.001). The adverse events were comparable in both groups. In addition, there was no significant correlation between POD/POCD and levels of SOD or HCY. ConclusionWe conclude that intraoperative intravenous 2 mg/kg MB could significantly reduce the incidences of POD and early POCD in elderly surgical patients, while not remarkably increase incidence of perioperative adverse events, suggesting MB may be clinically effective and safe for prevention of early postoperative neurocognitive disorders.

Current Evidence Regarding Biomarkers Used to Aid Postoperative Delirium Diagnosis in the Field of Cardiac Surgery-Review.

Postoperative cognitive disorders after cardiac surgery may manifest as postoperative delirium (POD) or later as postoperative cognitive dysfunction (POCD). The incidence of POD after cardiac surgery ranges from 16% to 73%. In contrast to POD, POCD is usually diagnosed after the discharge from hospital, with an incidence of 30 to 70% of cases, very often noticed only by close relative or friends, decreasing after six (20–30%) and twelve (15–25%) months after surgery. Perioperative cognitive disorders are associated with adverse short- and long-term effects, including increased morbidity and mortality. Due to the complexity of delirium pathomechanisms and the difficulties in the diagnosis, researchers have not yet found a clear answer to the question of which patient will be at a higher risk of developing delirium. The risk for POD and POCD in older patients with numerous comorbidities like hypertension, diabetes, and previous ischemic stroke is relatively high, and the predisposing cognitive profile for both conditions is important. The aim of this narrative review was to identify and describe biomarkers used in the diagnosis of delirium after cardiac surgery by presenting a search through studies regarding this subject, which have been published during the last ten years. The authors discussed brain-derived biomarkers, inflammation-related biomarkers, neurotransmitter-based biomarkers, and others. Work based on inflammation-related biomarkers, which are characterized by the low cost of implementation and the effectiveness of delirium diagnosis, seems to be the closest to the goal of discovering an inexpensive and effective marker. Currently, the use of a panel of tests, and not a single biomarker, brings us closer to the discovery of a test, or rather a set of tests ideal for the diagnosis of delirium after cardiac surgery.

Assessment of Postoperative Cognitive Dysfunction: Results From a Survey of Turkish Anaesthesiologists.

ObjectivePostoperative cognitive dysfunction (POCD) is one of the most common complications in elderly surgical patients. We conducted a survey study to evaluate the perspectives of Turkish anaesthesiologists on postoperative cognitive disorders.MethodsWe conducted a prospective online survey with questions and answers were recorded either in a Likert scale from 1 to 5 (completely disagree to completely agree) or as yes/no/do not know types of answers. Potential participants were contacted through an e-mail that included a brief introductory note, instructions, a link to the survey and the authors’ contact information.ResultsWe analysed 129 surveys (9.9% of total potential respondents). The majority believed that the risk of cognitive side effects should be considered when choosing the type of anaesthesia (87.6%) and that preoperative cognitive function should be routinely assessed (74.4%). When caring for an agitated and confused patient postoperatively, 56.6%, protocols to screen and manage postoperative cognitive disorders were rarely used. Nearly all respondents believe that postoperative delirium and POCD are neglected areas in anaesthesiology.ConclusionOverall, participants perceive postoperative cognitive disorders as important adverse outcomes following surgery and anaesthesia. They are aware of the main risk factors for their development but may lack information on the prevention and management postoperatively.

Role of neuroinflammation in pathogenesis of cognitive disorders after aortocoronary bypass grafting

Here we present the study aimed to identify dynamic quantitative changes in NSE, NGF, IL-1β, IL-10, IL-6 in patients with postoperative cognitive dysfunction after coronary artery bypass grafting. There were enrolled 44 patients aged 62 to 75 years after coronary artery bypass grafting. MoСA test data allowed to subdivide patients into two groups: group I – 22 patients with MoСA test data changed by less than 3b score before surgery and on day 7 after surgery, no postoperative cognitive dysfunction; Group II – 22 patients with deteriorated MoСA test score by more than 3b, with postoperative cognitive dysfunction. Level of NSE, NGF, IL-1β, IL-10, IL-6 was measured by using enzyme-linked immunosorbent assay (RD Systems, USA) at four time points: before surgery, after surgery, 24 hours and 7t day after surgery. Mean values were compared by using non-parametric Mann–Whitney test. Significance level was set at p 0.05. It was found that patients with postoperative cognitive disorders contained higher level of serum NSE before surgery, immediately postsurgery and 24 hours after surgery, evidences about a role for neuron-specific enolase in the pathogenesis of early postoperative cognitive complications. A pronouncedly increased level of serum nerve growth factor in patients from group II was revealed 24 hours after surgery and elevated concentration on day 7 after surgery, which may be related to compensatory processes in response to damaging factors. Patients from group II were noted to have more marked and prolonged pro-inflammatory response confirmed by dynamic changes in IL-6 level paralleled with elevated amount of serum IL-10. It might be linked to some IL-10-mediated pro-inflammatory properties or more extensive reaction to pronounced pro-inflammatory response. The association between increased NSE and IL-10 levels was revealed. Of interest, the level of IL-1β smoothly declined at all stages in group II patients potentially reflecting impaired anti-inflammatory response, despite the fact that IL-1β is a pro-inflammatory interleukin, or its lack contributes to developing postoperative cognitive disorders, due to disturbed neural plasticity and hippocampus functioning.