Postoperative cognitive dysfunction after liver transplantation

Other causes of neurocognitive impairment than covert hepatic encephalopathy (CHE) are very frequent, either alone or associated with CHE, in cirrhotic patients with cognitive complaints

BACKGROUND/AIMS

Although it is well admitted that cirrhotic patients display various causes of neurocognitive impairment (NI) hampering the diagnosis of covert hepatic encephalopathy (CHE), those are almost never investigated per se. The aims of this study were, in cirrhotic patients displaying cognitive complaints explored by a complete multimodal work-up, to assess: (1) the prevalence of CHE and/or that of other causes of NI and (2) their outcomes, according to the cause of NI.

METHODS

Prospective cohort of cirrhotic patients referred in a dedicated clinic because of cognitive complaints. Work-up included a complete neuropsychological assessment, electroencephalogram (EEG) and brain magnetic resonance imaging with spectroscopy. The diagnosis of CHE was made by an adjudication committee involving the physicians/neuropsychologist.

RESULTS

One hundred and twenty-three patients were included (alcohol/MASLD/virus in 63/53/14%, MELD = 11). Sixty-six per cent of them were diagnosed with CHE; among them, 73% exhibited also other causes of NI, mainly cerebrovascular diseases/psychiatric. Among patients without CHE, 48% and 59% displayed pathological Psychometric Hepatic Encephalopathy Score and animal naming test, respectively. Clinical improvement was observed in 77% of the patients re-evaluated after specific management. CHE, but not the other causes of NI, was independently associated with OHE occurrence.

CONCLUSION

Other causes of NI than CHE are frequent in patients with cirrhosis, and not ruled-out by the classical tests dedicated to CHE. Prognosis was influenced by the cause of NI. The management of patients even without CHE led to clinical improvement, underlining the need for a multifaceted approach of cirrhotic patients with cognitive complaints.

Prevalence of cognitive impairment in liver transplant recipients

Liver transplant (LT) recipients have a high burden of cognitive impairment risk factors identified in other populations, yet little work has explored cognition in the United States LT population. We characterized prevalence of cognitive impairment (CI) in LT recipients pre-LT and ≥3 months post-LT. Adult LT recipients with cirrhosis but without active pre-LT hepatic encephalopathy (HE) were screened for CI using the Montreal Cognitive Assessment (MoCA) for CI (MoCA <24) both pre-LT and ≥3 months post-LT. The association between cognitive performance and recipient characteristics was assessed using logistic regression. Of 107 LT recipients, 36% had pre-LT CI and 27% had post-LT CI [median (Q1-Q3) MoCA 26 (23-28)]. Each 1-point increase in pre-LT MoCA was associated with 26% lower odds of post-LT cognitive impairment (aOR .74, 95% CI .63-.87, p < .001), after adjusting for recipient age, history of HE, and time since LT. In this study of cirrhosis recipients without active pre-LT HE, cognitive impairment was prevalent before LT and remained prevalent ≥3 months after LT (27%), long after effects of portal hypertension on cognition would be expected to have resolved. Our data expose an urgent need for more comprehensive neurologic examination of LT recipients to better identify, characterize, and address predictors of post-LT cognitive impairment.

Anaesthesia management for liver transplantation: A narrative review

Orthotopic liver transplantation is the definitive standard treatment for end-stage liver disease. Orthotopic liver transplantation anaesthesia management is a complex procedure that requires a multidisciplinary team approach. Understanding the complex pathophysiology of end-stage liver disease and its complications in the affected systems is essential for proper anaesthesia management in orthotopic liver transplantation. Orthotopic liver transplantation is a dynamic process, and preoperative optimisation is essential in these patients. Therefore, anaesthesiologists should focus on rapidly fluctuating physiology, haemodynamics, metabolic, and coagulation status in the anaesthesia management of these patients. Perioperative care and anaesthesia for orthotopic liver transplantation can be divided into preoperative evaluation, anaesthesia induction and management, dissection, anhepatic, neo-hepatic, and postoperative care, with essential anaesthetic considerations at each point. Considering the clinical situation, haemodynamic changes, misapplications, knowledge, attitude, and multimodal and multidisciplinary approach are vital in anaesthesia and the perioperative period. In our review, in line with the literature, we aimed to present the perioperative and anaesthesia management in orthotopic liver transplantation patients.

Preoperative evaluation of the elderly patient

Nowadays, the pre-operative evaluation of older patients is a critical step in the decision-making process. Clinical assessment and care planning should be considered a whole process rather than separate issues. Clinicians should use validated tools for pre-operative risk assessment of older patients to minimize surgery-related morbidity and mortality and enhance care quality. Traditional pre-operative consultation often fails to capture the pathophysiological and functional profiles of older patients. The elderly's pre-operative evaluation should be focused on determining the patient's functional reserve and reducing any possible peri-operative risk. Therefore, older adults may benefit from the Comprehensive Geriatric Assessment (CGA) that allows clinicians to evaluate several aspects of elderly life, such as depression and cognitive disorders, social status, multi-morbidity, frailty, geriatric syndromes, nutritional status, and polypharmacy. Despite the recognized challenges in applying the CGA, it may provide a realistic risk assessment for post-operative complications and suggest a tailored peri-operative treatment plan for older adults, including pre-operative optimization strategies. The older adults' pre-operative examination should not be considered a mere stand-alone, that is, an independent stage of the surgical pathway, but rather a vital step toward a personalized therapeutic approach that may involve professionals from different clinical fields. The aim of this review is to revise the evidence from the literature and highlight the most important items to be implemented in the pre-operative evaluation process in order to identify better all elderly patients' needs.

Implication of age-related changes on anesthesia management

Elderly patients have a high risk of perioperative morbidity and mortality. Pluri-morbidities, polypharmacy, and functional dependence may have a great impact on intraoperative management and request specific cautions. In addition to surgical stress, several perioperative noxious stimuli such as fasting, blood loss, postoperative pain, nausea and vomiting, drug adverse reactions, and immobility may trigger a derangement leading to perioperative complications. Older patients have a high risk of major hemodynamic derangement due to aging of the cardiovascular system and associated comorbidities. The hemodynamic monitoring as well as fluid therapy should be the most accurate as possible. Aging is accompanied by decreased renal function, which is related to a reduction in renal blood flow, renal mass, and the number and size of functioning nephrons. Drugs eliminated predominantly by the renal route need dosage adjustments based on residual renal function. Liver mass, hepatic blood flow, and intrinsic metabolic activity are decreased in the elderly, and all drugs metabolized by the liver have a variable half-life, thus requiring dose reduction. Decreased neural plasticity contributes to a high risk for postoperative delirium. Monitoring of anesthesia depth should be mandatory to avoid overdosage of hypnotic drugs. Prevention of postoperative pulmonary complications requires both protective ventilation strategies and adequate recovery of neuromuscular function at the end of surgery. Avoidance of hypothermia cannot be missed. The aim of this review is to describe comprehensive strategies for intraoperative management plans tailored to meet the unique needs of elderly surgical patients, thus improving outcomes in this vulnerable population.

Perioperative analgesia in the elderly

The administration of analgesic drugs in elderly patients should take into account age-related physiological changes, loss of efficiency of homeostatic mechanisms, and pharmacological interactions with chronic therapies. Underestimation of pain in patients with impaired cognition is often linked to difficulties in pain assessment. In the preoperative phase, it is essential to assess the physical status, cognitive reserve, and previous chronic pain conditions to plan effective analgesia. Furthermore, an accurate pharmacological history of the patient must be collected to establish any possible interaction with the whole perioperative analgesic plan. The use of analgesic drugs with different mechanisms of action for pain relief in the intraoperative phase is a crucial step to achieve adequate postoperative pain control in older adults. The combined multimodal and opioid-sparing strategy is strongly recommended to reduce side effects. The use of various adjuvants is also preferable. Moreover, the implementation of non-pharmacological approaches may lead to faster recovery. High-quality postoperative analgesia in older patients can be achieved only with a collaborative interdisciplinary team. The aim of this review is to highlight the perioperative pain management strategies in the elderly with a special focus on intraoperative pharmacological interventions.

Evaluation of the brain cellular damage during liver transplantations

Background

Neuroinflammation in patients undergoing major surgery can lead to neuronal damage, and neuronal damage can be detected through the measurement of biochemical markers of brain damage. S100 beta (S100 β), neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP) levels are considered good biomarkers to detect brain damage that emerged with neurotoxicity.

Aim

To evaluate neuronal damage during liver transplantations.

Materials and Methods

After approval of the ethics committee and patient consents, preoperative and postoperative cognitive functions of 33 patients undergoing liver transplantation were measured using the Mini Mental State Examination (MMSE), whereas simultaneous neuronal damage was evaluated through the measurement of S100β, NSE, and GFAP levels.

Results

There was no statistically significant difference between preoperative and postoperative MMSE. There was a statistically significant decrease in postoperative GFAP (P < 0.05) and a statistically significant increase in NSE (P < 0.05) compared to preoperative values. The decrease in S100β (P > 0.05) level was statistically insignificant.

Conclusions

Neuroprotective approaches in anesthesia protocol protect patients from brain damage during liver transplantation and prevent the development of postoperative cognitive dysfunction. Since the significant increase in NSE levels during liver transplantations was deemed to have been associated with causes other than neuronal damage, NSE should not be evaluated as a marker of brain damage in these operations.

Pathogenic factors of cognitive dysfunction after liver transplantation: an observational study

OBJECTIVES

Neurocognitive complications significantly reduce long-term health-related quality of life in patients undergoing liver transplantation; however, few studies have focused on their perioperative cognitive status. The authors designed a prospective observational study to determine the incidence and risk factors of posttransplant cognitive dysfunction.

METHODS

This study included patients with end-stage liver disease who were on the liver transplantation waiting list. We performed an investigation with a neuropsychological battery before and 1 week after the successful transplant, analyzed the changes, and further explored the complicated perioperative factors that contribute to cognitive dysfunction.

RESULTS

A total of 132 patients completed all the investigations. Compared with healthy controls and preoperative cognitive performance, 54 patients experienced deterioration, 50 patients remained unchanged, and 28 patients showed rapid improvement. Logistic regression analysis showed that age [odds ratio (OR) = 1.15, 95% confidence interval (CI, 1.07-1.22), P  < 0.001], the model for end-stage liver disease (MELD) score [OR = 1.07, 95% CI (1.03-1.13), P  = 0.038], systemic circulation pressure [OR = 0.95, 95% CI (0.91-0.99), P  = 0.026] within the first 30 min after portal vein opening, and total bilirubin concentration [OR = 1.02, 95% CI (1.01-1.03), P  = 0.036] on the seventh day post-transplant were closely related to the deterioration of cognitive function.

CONCLUSION

The incidences of deterioration, maintenance, and improvement in cognitive function were 40.9%, 37.9%, and 21.2%, respectively. Increasing age, higher MELD score, lower perfusion pressure in the early stage of the new liver, and higher total bilirubin concentration postoperatively may be independent pathogenic factors.

Moderate-to-high risk of obstructive sleep apnea with excessive daytime sleepiness is associated with postoperative neurocognitive disorders: a prospective one-year follow-up cohort study

Background

Few studies found that obstructive sleep apnea (OSA) may be related to postoperative neurocognitive disorders (PND) including postoperative delirium (POD) and cognitive decline (POCD) in the early postoperative period. However, the results are controversial and need further verification, and no research has explored the effect of OSA on the incidence of PND during the 1-year follow-up periods. Furthermore, OSA patients with excessive daytime sleepiness (EDS) as a severe phenotype have more significant neurocognitive impairments, but the relationship between OSA with EDS and PND within 1 year after surgery has not been studied.

Objectives

To explore the effect of moderate-to-high risk of OSA and the moderate-to-high risk of OSA with EDS on PND within 1 year after surgery.

Methods

In this prospective cohort study, including 227 older patients, moderate-to-high risk of OSA (using STOP-BANG), subjective EDS (using Epworth Sleepiness Scale), and objective EDS (using Actigraphy) were selected as exposures. Key outcomes included POD during hospitalization (using Confusion Assessment Method-Severity), POCD at discharge, 1-month and 1-year after surgery (using Mini-Mental State Examination and Telephone Interview for Cognitive Status-40). We applied multiple logistic regression models to estimate the effect of moderate-to-high risk of OSA and moderate-to-high risk of OSA with EDS on PND.

Results

In the multivariate analysis, moderate-to-high risk of OSA was not associated with POD during hospitalization and POCD at discharge, 1-month, and 1-year after surgery (p > 0.05). However, the moderate-to-high risk of OSA with subjective EDS was related to POCD at discharge compared to the moderate-to-high risk of OSA or normal group (no moderate-to-high risk of OSA and no EDS) (p < 0.05). In addition, moderate-to-high risk of OSA with objective EDS was associated with POCD at discharge, 1-month, and 1-year postoperatively compared to the moderate-to-high risk of OSA or normal group (p < 0.05).

Conclusion

Moderate-to-high risk of OSA with EDS, not moderate-to-high risk of OSA alone, was a clinically helpful predictor for POCD within 1-year after surgery and should be routinely assessed before surgery.

The prediction of postoperative delirium with the preoperative bispectral index in older aged patients: a cohort study

BACKGROUND

Postoperative delirium (POD) is the most common postoperative complication in elderly patients, especially in older aged patients (aged 75 years or over). The development of electroencephalography analysis could provide indicators for early detection, intervention, and evaluation. If there are pathophysiological changes in the brain, the BIS value will also change accordingly. In this study, we investigated the predictive value of the preoperative bispectral (BIS) index in POD for patients aged over 75 years.

METHODS

In this prospective study, patients (≥ 75 years) undergoing elective non-neurosurgery and non-cardiac surgery under general anesthesia were included (n = 308). Informed consent was obtained from all involved patients. Before the operation and during the first 5 postoperative days, delirium was assessed with the confusion assessment method by trained researchers twice every day. Thereafter, the preoperative bedside BIS of each patient was dynamically acquired by the BIS VISTA monitoring system and the BIS monitoring of electrodes. A series of evaluation scales were assessed before and after surgery. A preoperative predictive score was generated according to the results of multivariable logistic regression. The receiver operating characteristic curves were drawn and the area under the curves was estimated to evaluate the perioperative diagnostic values of BIS and preoperative predictive score for POD. The specificity, sensitivity, positive predictive value (PPV), and negative predictive (NPV) value were calculated.

RESULTS

Delirium occurred in 50 of 308 (16.2%) patients. The median BIS of delirious patients was 86.7 (interquartile range [IQR] 80.0-94.0), lower than that of the non-delirious 91.9 (IQR 89.7-95.4, P < 0.001). According to the ROC curve of the BIS index, the optimal cut-off value was 84, with a sensitivity of 48%, specificity of 87%, PPV 43%, NPV 89% for forecasting POD and the area under curves was 0.67. While integrating BIS, mini-mental state examination, anemia, activities of daily living, and blood urea nitrogen, the model had a sensitivity of 78%, specificity of 74%, PPV of 0.37%, and NPV of 95% for forecasting POD, and the area under curves was 0.83.

CONCLUSIONS

Preoperative bedside BIS in delirium patients was lower than that in non-delirium patients when undergoing non-neurosurgery and non-cardiac surgery in patients aged over 75. The model of integrating BIS, mini-mental state examination, anemia, activities of daily living, and blood urea nitrogen is a promising tool for predicting postoperative delirium in patients aged over 75.

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.

Subjective Cognition is Related to Patient-Reported Symptom Distress and Work Productivity Among Liver Transplant Recipients

Cognitive decline may prevent liver transplant (LT) recipients from staying healthy and independent. This study examined associations of objective and subjective, rated by LT recipients and caregivers, cognitive decline with patient-reported physical and psychological symptom distress, ability to perform household tasks, and workplace productivity among LT recipients. Sixty pairs of LT recipients and caregivers participated in this cross-sectional study. Subjective cognition was measured by the Everyday Cognition. Objective cognition was assessed with four cognitive tests, including the Repeatable Battery for the Assessment of Neuropsychological Status. Patient-reported outcomes were assessed with the Rotterdam Symptom Checklist-Modified, Profile of Mood States-Short Form, Creative Therapy Consultants Homemaking Assessment, and Work Limitations Questionnaire. Linear regression analyses related objective and subjective cognition to the patient-reported outcomes. While objective cognitive decline was not associated with any patient-reported outcomes, subjective cognitive decline was significantly associated with the outcomes. Higher LT recipient self-rated cognitive decline was associated with higher physical symptom distress ( β = 0.30, p = 0.006) and workplace productivity loss ( β = 14.85, p < 0.0001). Higher caregiver-rated cognitive decline was associated with lower household tasks performance ( β = -18.55, p = 0.015). Findings suggest to consider subjective cognition when developing an individualized post-transplant care plan.

Subjective Cognition Reported by Caregivers Is Correlated With Objective Cognition in Liver Transplant Recipients

Objective cognitive assessments, a gold standard diagnostic tool for cognitive impairment, may not be feasible in busy liver transplantation (LT) practice because they are often time consuming. This study determined whether subjective cognition, patients' self-ratings and/or caregivers' ratings of patients' cognition, reflects objective cognition in LT recipients. A convenience sample of 60 adult LT recipients and their caregivers, recruited at a single transplant center, participated in this cross-sectional descriptive study. Subjective cognition (ie, recipient self-rated and caregiver rated) was measured using the Everyday Cognition (ECog; global and 6 domain scores). Objective global and domain-specific cognition of recipients was measured using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Trail Making Test parts A and B, Digit Span Backward, and Rey-Osterrieth Complex Figure. Agreement between LT recipients' ECog scores and those of their caregivers was fair to moderate (intraclass correlation coefficient = 0.48 for global score, 0.35-0.56 for domain scores). Significant, albeit rather weak, correlations were found between subjective and objective scores. Recipients' ECog visuospatial abilities scores were correlated with Rey-Osterrieth Complex Figure scores (r_s  = -0.39; P = 0.007), whereas caregivers' ECog global, attention, visuospatial abilities, and organization scores were, respectively, correlated with the scores of RBANS global (r_s  = -0.33; P = 0.04) and attention (r_s  = -0.46; P = 0.005), Rey-Osterrieth Complex Figure (Copy; r_s  = -0.34; P = 0.03), and Trail Making Test part A (r_s  = 0.31; P = 0.049). The findings suggest that caregivers may estimate LT recipients' cognition better than recipients themselves. Caregivers may provide supplemental information that could be useful for clinicians when considering the cognitive functioning of LT recipients.

Hepatic Encephalopathy and Liver Transplantation: The Past, Present, and Future Toward Equitable Access

Cirrhosis is a debilitating chronic disease with high morbidity and mortality, with the only real cure being liver transplantation (LT). Currently, we allocate organs for transplantation based on the Model for End-Stage Liver Disease-Sodium (MELD-Na) score that does not account for hepatic encephalopathy (HE). HE affects patients, families, and the health care system because of high rates of recurrence and major readmission burden. Moreover, HE casts a long shadow even after LT. Accounting for HE and incorporating it into the current allocation system has many proponents, but the framework to do this is currently lacking because of differences in consensus or in operationalization parameters. We review the latest evidence of the burden of HE, management of HE before and after LT, and evaluate pros and cons of several methods of diagnosing HE objectively to ensure early and equitable access to LT in this underserved population.

Hepatic encephalopathy: Novel insights into classification, pathophysiology and therapy

Hepatic encephalopathy (HE) is a frequent and serious complication of both chronic liver disease and acute liver failure. HE manifests as a wide spectrum of neuropsychiatric abnormalities, from subclinical changes (mild cognitive impairment) to marked disorientation, confusion and coma. The clinical and economic burden of HE is considerable, and it contributes greatly to impaired quality of life, morbidity and mortality. This review will critically discuss the latest classification of HE, as well as the pathogenesis and pathophysiological pathways underlying the neurological decline in patients with end-stage liver disease. In addition, management strategies, diagnostic approaches, currently available therapeutic options and novel treatment strategies are discussed.

Cognitive Function in Liver Transplantation

PURPOSE OF REVIEW

Liver transplantation (LT) remains the only way to cure patients with severe liver diseases. Important questions about neurological sequelae and quality of life after LT have emerged. In this review, we discuss the neurocognitive changes associated with LT and we conclude with recommendations in this regard for patients, caregivers, and physicians.

RECENT FINDINGS

Compared with other solid organ recipients, LT patients tend to have a higher incidence (up to 30%) of neurological complications post-LT. Even in absence of previous episodes of hepatic encephalopathy (HE), some patients display new onset of neurological symptoms post-LT, raising the concern about the role of other factors that may have a direct impact on cognitive function.

SUMMARY

Different mechanisms have been postulated to explain these postoperative neurological symptoms. They include sequelae of HE, persistent impairment of cognitive function due to cirrhosis, or postoperative decompensation of an unknown or undiagnosed neurodegenerative disorder.

Joint consensus on anesthesia in urologic and gynecologic robotic surgery: specific issues in management from a task force of the SIAARTI, SIGO, and SIU

INTRODUCTION

Proper management of patients undergoing robotic-assisted urologic and gynecologic surgery must consider a series of peculiarities in the procedures for anesthesiology, critical care medicine, respiratory care, and pain management. Although the indications for robotic-assisted urogynecologic surgeries have increased in recent years, specific guidance documents are still lacking.

EVIDENCE ACQUISITION

A multidisciplinary group including anesthesiologists, gynecologists, urologists, and a clinical epidemiologist systematically reviewed the relevant literature and provided a set of recommendations and unmet needs on peculiar aspects of anesthesia in this field.

EVIDENCE SYNTHESIS

Nine core contents were identified, according to their requirements in urogynecologic robotic-assisted surgery: patient position, pneumoperitoneum and ventilation strategies, hemodynamic variations and fluid therapy, neuromuscular block, renal surgery and prevention of acute kidney injury, monitoring the Department of anesthesia, postoperative delirium and cognitive dysfunction, prevention of postoperative nausea and vomiting, and pain management in endometriosis.

CONCLUSIONS

This consensus document provides guidance for the management of urologic and gynecologic patients scheduled for robotic-assisted surgery. Moreover, the identified unmet needs highlight the requirement for further prospective randomized studies.

Neurological Complications Occurring After Liver Transplantation: Role of Risk Factors, Hepatic Encephalopathy, and Acute (on Chronic) Brain Injury

Orthotopic liver transplantation (LT) remains the only way to definitively cure patients with the most severe liver diseases. Because the survival rate is now fairly high, important questions about neurological sequelae or quality of life after LT have emerged. Indeed, LT represents a peculiar situation because up to 30% of patients present with neurological symptoms after LT compared with only 4% after cardiac transplant and 0.5% after renal transplant. These postoperative neurological symptoms have long been interpreted as sequelae of hepatic encephalopathy (HE). However, postoperative decompensation of an unknown cerebral condition due to the pathophysiology of cirrhosis or undiagnosed neurodegenerative disorders or aging constitute other possibilities that are underrecognized. Some patients who undergo LT for acute liver failure and patients with cirrhosis without episodes of HE and without any previous cerebral alteration also display post-LT neurological symptoms. This latter situation speaks in favor of a direct adverse effect of either general anesthesia, the surgical procedure, or factors related to the postoperative intensive care unit (ICU) environment. The role of inflammation, which has been described in the ICU setting, could also be a crucial determinant. In this review, we will discuss the neurological complications associated with LT, the neurocognitive complications after LT, and how to assess the LT-related neurological or neurocognitive complications. Furthermore, we will review the various hypotheses surrounding post-LT neurocognitive impairment and will conclude with recommendations for future directions.

Liver Transplant Recipients Older Than 60 Years Show Executive and Memory Function Improvement Comparable to Younger Recipients

BACKGROUND

Increasing numbers of patients over the age of 60 are undergoing liver transplantation.

OBJECTIVE

We sought to determine whether age or clinical morbidities were associated with pre- and post-transplant executive and memory performance using the Brief Test of Adult Cognition by Telephone (BTACT).

METHODS

Participants included 36 recipients with n = 20 in the older group (>60 y) and n = 16 in the younger group (≤60 years). The BTACT was administered an average of 3 months before transplant, and at follow-up post-transplant intervals of 3, 6, and 9 months. BTACT composite scores for memory and executive function with age and education norms were obtained.

RESULTS

Older recipients were more likely to have hepatocellular carcinoma, a lower biological MELD score at transplant, less cellular rejection, and fewer post-operative hospital days. Older and younger recipients showed comparable pre-transplant executive and memory function and comparable post-transplant improvement. Both older and younger patients showed statistically significant improvement in executive function scores at 3 months post-transplant and maintained improvement at 6 and 9 months. Memory function improved significantly in older patients by 6 months post-transplant but did not improve significantly in the younger group.

CONCLUSION

Older liver transplant recipients were more likely to have hepatocellular carcinoma and a lower biological MELD score than younger recipients, but both age groups showed comparable pre-transplant cognitive performance and post-transplant cognitive improvement. Additionally, a normed telephone test can be used to effectively screen and track executive and memory function post-transplant.

Psychopharmacology in transplantation medicine

Organ transplantation has become a well-established treatment option in patients with end-stage organ diseases. Although quality of life has markedly improved, psychiatric disorders before and after transplantation are more frequent compared to the general population. Psychopharmacological treatment is recommended for almost all mental disorders according to current guidelines, but may pose particular problems in organ transplant patients. Changes in the metabolism and elimination of drugs during organ insufficiency, drug interactions, and overlapping side effects between psychopharmacological and immunosuppressive drugs are challenging problems in clinical management. Furthermore, questions frequently arise concerning the use of psychopharmacological treatment options for sleeping and anxiety disorders. This article reviews psychopharmacology in organ transplant patients, with particular attention to frequent psychiatric disorders observed in the disease course of end-stage organ diseases.

Effect of bispectral index-guided anesthesia on consumption of anesthetics and early postoperative cognitive dysfunction after liver transplantation: An observational study

The objective of this study was to summarize the incidence of postoperative cognitive dysfunction (POCD) after 7days following liver transplantation (LT), and to evaluate the effectiveness of bispectral index (BIS) guided anesthetic intervention in reducing POCD. Additional serum concentrations of S100β and neuron-specific enolase (NSE) were detected during surgery to determine whether they were reliable predictors of POCD.Patients who underwent LT at Beijing YouAn Hospital Affiliated to Capital University of Medical Science from January 2014 to December 2015 were enrolled. BIS monitor was needed during surgery. Patients who underwent LT without BIS monitoring during August 2012 to December 2014 served as historical controls. A battery of 5 neuropsychological tests were performed and scored preoperatively and 7days after surgery. POCD was diagnosed by the method of one standard deviation (SD). The blood samples of BIS group were collected at 5 time points: just before induction of general anesthesia (T0), 60 minutes after skin incision (T1), 30 minutes after the start of the anhepatic phase (T2), 15 minutes after reperfusion of the new liver (T3), and at 24 hours after surgery (T4).A total of 33 patients were included in BIS group, and 27 in the control group. Mean arterial pressure was different between 2 groups at 30 minutes after the start of the anhepatic phase (P = .032). The dose of propofol using at anhepatic phase 30 min and new liver 15 min was lower in the BIS group than control group (0.042 ± 0.021 vs. 0.069 ± 0.030, P < .001; 0.053 ± 0.022 vs. 0.072 ± 0.020, P = .001). Five patients were diagnosed as having POCD after 7 days in the BIS group and the incidence of POCD was 15.15%. In the control group, 9 patients had POCD and the incidence of POCD was 33.33%. The incidence of POCD between 2 groups had no statistical difference (P = .089). S100β increased at stage of anhepatic 30 minutes (T2) and new liver 15 minutes (T3) compared with the stage of before anesthesia (T0) (1.49 ± 0.66 vs. 0.72 ± 0.53, P < .001; 1.92 ± 0.78 vs. 0.72 ± 0.53, P < .001). NSE increased at stage of anhepatic 30 minutes (T2) and new liver 15 minutes (T3) compared with the stage of before anesthesia (T0) (5.80 ± 3.03 vs. 3.58 ± 3.24, P = .001; 10.04 ± 5.65 vs. 3.58 ± 3.24, P < .001). At 24 hours after surgery, S100β had no difference compared to one before anesthesia (1.0 ± 0.62 vs. 0.72 ± 0.53, P = .075), but NSE still remained high (5.19 ± 3.64 vs. 3.58 ± 3.24, P = .043). There were no significant differences in the serum concentrations of S100β between patients with and without POCD at 5 time points of operation (P > .05). But at 24 hours after surgery, NSE concentrations were still high of patients with POCD (8.14 ± 3.25 vs. 4.81 ± 3.50, P = .035).BIS-guided anesthesia can reduce consumption of propofol during anhepatic and new liver phase. Patients in BIS group seem to have a mild lower incidence of POCD compared to controls, but no statistical significant. The influence of BIS-guided anesthesia on POCD needs to be further confirmed by large-scale clinical study. S100β protein and NSE are well correlative with neural injury, but NSE is more suitable for assessment of incidence of postoperative cognitive deficits after surgery.

An update on anesthetics and impact on the brain

INTRODUCTION

While anesthetics are indispensable clinical tools and generally considered safe and effective, a growing concern over the potential neurotoxicity of anesthesia or specific anesthetic agents has called into question the safety of general anesthetics, especially when administered at extremes of age. Areas covered: This article reviews and updates research findings on the safety of anesthesia and anesthetics in terms of long-term neurotoxicity, with particular focus on postoperative cognitive dysfunctions, Alzheimer's disease and dementias, developing brain, post-operative depression and autism spectrum disorder. Expert opinion: Exposure to general anesthetics is potentially harmful to the human brain, and the consequent long-term cognitive deficits should be classified as an iatrogenic pathology, and considered a public health problem. The fact that in laboratory and clinical research only certain anesthetic agents and techniques, but not others, appear to be involved, raises the problem on what is the safest and the least safe anesthetic to maximize anesthesia efficiency, avoid occurrence of adverse events, and ensure patient safety. New trends in research are moving toward the theory that neuroinflammation could be the hallmark of, or could have a pivotal role in, several neurological disorders.

Noteworthy Literature Published in 2016 for Abdominal Organ Transplantation Anesthesiologists

More than 3000 peer-reviewed publications on the topic of liver transplantation were published in 2016. The goal of this article is to provide a concise review of pertinent literature for anesthesiologists who participate in liver transplantation. The authors selected and presented 33 articles published in 2016 on the topics of MELD policy; cardiovascular, pulmonary, and renal issues; coagulation and transfusion; anesthetic agents; hemodynamic monitors; acute liver failure; and donor issues.