Neurologic complications after liver transplantation

Deep Brain Stimulation with Double Targeting of the VIM and PSA for the Treatment of Rare Tremor Syndromes

INTRODUCTION

In tremor syndromes, pharmacological therapy is the primary treatment, but deep brain stimulation (DBS) is used when it is insufficient. We explore the use of DBS, focusing on the globus pallidus internus for dystonia and the ventral intermediate nucleus (VIM) for tremor conditions. We introduce the posterior subthalamic area (PSA) as a potential target, suggesting its efficacy in tremor reduction, particularly in rare tremor syndromes. We aim to evaluate the efficacy and safety of double targeting the VIM and PSA in rare tremor conditions, highlighting the limited existing data on this.

METHODS

Between 2019 and 2023, 22 patients with rare tremor syndromes were treated with bilateral DBS of the VIM and PSA. This case series consisted of 7 isolated head tremor, 1 hepatic encephalopathic tremor due to Abernethy syndrome, 2 voice tremor, 4 dystonic tremor, and 8 Holmes tremor (2 multiple sclerosis, 2 cerebellar insult, and 4 posttraumatic) patients. Patients' preoperative and 12-month postoperative tremor scores were compared, and the optimum VIM and PSA stimulation areas were investigated.

RESULTS

There was a significant reduction in the mean TRS score from 3.70 (±0.57) to 0.45 (±0.68) after 12 months of surgery. Specific outcomes for different indications were observed: for head tremor, 6 of 7 patients showed a reduction in TRS scores to 0 points; the vocal tremor patients demonstrated improvement; this change was not statistically significant, which is likely to be due to the low number of patients in this subgroup; the dystonic tremor patients showed either complete tremor abolition or a reduction in TRS scores; the Holmes tremor patients showed an 80% reduction in TRS scores; and the hepatic encephalopathy tremor and Abernethy syndrome patients showed a 75% improvement in TRS scores. The stimulation parameters converged on the VIM and dorsal PSA. Complications included the need for electrode repositioning, infections requiring electrode removal and re-implantation, dysarthria, and stimulation-induced ataxia, which was resolved by adjusting the stimulation parameters.

DISCUSSION

The literature on DBS for rare tremors is limited. Double targeting of the VIM and PSA appears to produce promising improvements on the outcomes reported in the existing literature on VIM-only DBS. The proximity of the VIM and PSA allows for flexible electrode placement, contributing to the potential success of the dual-target approach. We also discuss the theoretical advantages of targeting the PSA based on the distribution of tremor circuits, emphasizing the need for further research and electrophysiological studies.

Critical Assessment of the Neurological Complications during High-Risk Anesthesia Procedures

Damage to the peripheral and central nervous systems is frequently irreversible. Surgically induced neurological damage and anesthesia may result in catastrophic situations for patients and their families. The incidence of significant neurological complications during the perioperative period is examined in this article. In contrast to other organs like the kidney, heart, liver, lungs, and skeletal system, native neurological function cannot be replaced with artificial parts or devices soon. Ignoring brain function during the perioperative period has been a systemic problem in anesthesiology, even though the central and peripheral nervous systems are crucial. This bold claim is intended to draw attention to the fact that, unlike the circulatory and respiratory systems, which have been routinely monitored for decades, the brain and other neural structures do not have a standard monitoring during surgery and anesthesia. Given that the brain and spinal cord are the principal therapeutic targets of analgesics and anesthetics, this deficiency in clinical care is even more alarming. Organs that are notoriously hard to repair or replace after damage have, up until now, received comparatively little attention. In this article, a succinct overview of five neurological complications associated with surgery and anesthesia is presented. After critically reviewing the literature on the subject, the article is focused to common (delirium), controversial (postoperative cognitive decline), and potentially catastrophic (stroke, spinal cord ischemia, or postoperative visual loss) adverse events in the neurological surgery setting. The findings will increase awareness of major neurological complications to the involved surgical and anesthesia team and enhance preventive and treatment strategies during the perioperative period.

Perioperative care in acute liver failure: An anaesthesiologist perspective in the operating theatre

Acute liver failure (ALF) is a life-threatening condition characterized by rapid liver function deterioration, necessitating a multidisciplinary approach for optimal perioperative care. This comprehensive review focuses on the critical role of the anaesthesiologist throughout the preoperative, intraoperative, and postoperative phases, addressing the unique challenges posed by ALF. The article begins with an exploration of ALF, underlining the urgency of timely referral to specialized hepatology centres. Liver transplantation emerges as a life-saving intervention, and the complex decision-making process is discussed, emphasizing the need for a multidisciplinary team to assess transplantation candidacy based on established prognostic criteria. In the preoperative phase, the review stresses the importance of early engagement with tertiary liver centres for timely referrals and identifies patients suitable for transplantation. Safe transport protocols are detailed, highlighting the meticulous planning required for the secure transfer of ALF patients between healthcare facilities. The intraoperative management section delves into the anaesthesiologist's key concerns, including neurological status, sepsis, acute kidney injury, body mass index, and preoperative fasting. Hemodynamic stability, fluid management, and coagulation balance during surgery are emphasized, with insights into anaesthesia techniques, vascular access, monitoring, and hemodynamic management tailored to the challenges posed by ALF patients. The postoperative care is thoroughly examined covering neurological, hemodynamic, metabolic, renal, and nutritional aspects. Management of ALF involves multidisciplinary team, including nephrology for continuous renal replacement therapy, transfusion medicine for plasma exchange, critical care for overall patient care, nutritionists for ensuring adequate nutrition, and hepatologists as the primary guides. In conclusion, the review recognizes the anaesthesiologist as a linchpin in the perioperative care of ALF patients. The integration of safe transport protocols and multidisciplinary approach is deemed crucial for navigating complexities of ALF, contributing to improved patient outcomes. This article serves as an invaluable resource for gastroenterologist and intensivists, enhancing their understanding of the anaesthesiologist's indispensable role in the holistic care of ALF patients in an ever-evolving healthcare landscape.

Clinical Impact and Risk Factors of Seizure After Liver Transplantation: A Nested Case-Control Study

Seizures are a frequent neurological consequence following liver transplantation (LT), however, research on their clinical impact and risk factors is lacking. Using a nested case-control design, patients diagnosed with seizures (seizure group) within 1-year post-transplantation were matched to controls who had not experienced seizures until the corresponding time points at a 1:5 ratio to perform survival and risk factor analyses. Seizures developed in 61 of 1,243 patients (4.9%) at median of 11 days after LT. Five-year graft survival was significantly lower in the seizure group than in the controls (50.6% vs. 78.2%, respectively, p < 0.001) and seizure was a significant risk factor for graft loss after adjusting for variables (HR 2.04, 95% CI 1.24-3.33). In multivariable logistic regression, body mass index <23 kg/m2, donor age ≥45 years, intraoperative continuous renal replacement therapy and delta sodium level ≥4 mmol/L emerged as independent risk factors for post-LT seizure. Delta sodium level ≥4 mmol/L was associated with seizures, regardless of the severity of preoperative hyponatremia. Identifying and controlling those risk factors are required to prevent post-LT seizures which could result in worse graft outcome.

Early neurologic complications after liver transplant are associated with reduced long-term survival and increased rates of rejection

Neurologic complications (NCs) are common following liver transplantation (LT) and have been associated with impaired short-term survival. The impact of NC on long-term survival is less defined. We aimed to characterize these outcomes and assess for risk factors for post-LT NC. We performed a single-center, retrospective review of 521 patients with LT from 2016 to 2020. Baseline clinical and laboratory factors, intraoperative events, and outcomes were compared between patients with and without NC. The 5-year overall and rejection-free survival was estimated using the Kaplan-Meier analysis. Multivariable logistic regression assessed for an independent relationship between risk factors and the development of NC. Among 521 LT recipients, 24% experienced post-LT NC. Overall and rejection-free survival at 5 years was, respectively, 69% and 75% among those with NC versus 87% and 88% among those without NC (log-rank < 0.001). Among those who survived the first 3 months after LT, overall survival but not rejection-free survival was reduced among patients with NC. Risk factors for developing NC included peri-LT serum sodium (ΔSNa) ≥ 6 (29.4% vs. 20.5%, p = 0.04), grade 3 or 4 HE pre-LT, SNa < 125 pre-LT, and more intraoperative transfusions. In a multivariable logistic regression model controlling for described variables, SNa < 125 (or 0.21, 95% CI, 0.06-0.74) at LT and pre-LT HE grade 3 or 4 (or 0.45, 95% CI, 0.26-0.76) was independently associated with NC. Long-term survival was reduced among patients who developed NC in the immediate post-transplant period, even when censoring those who died in the first 3 months. Post-LT NC was associated with perioperative ΔSNa ≥ 6. Optimization of SNa pre-LT > 125 and limiting perioperative ΔSNa <6 mEq/L might have a beneficial impact in decreasing NC post-LT, which may improve long-term post-LT survival.

Liver Transplantation and the Elderly Candidate: Perioperative Considerations

Pioneered by Thomas Starzl in the early 1970s, liver transplant (LT) is nowadays often considered a final intervention and standard of care to cure many forms of acute and chronic end-stage liver diseases. Started in recipients younger than 60 years old, LT indications are now much broader, and at least, one-fifth of the candidates are older than 65 years. Problems associated with ageing and frailty in LT recipients and their impact on the entire perioperative course are discussed according to a modern anesthesiological perspective and the anesthesiologist covering the role of the perioperative (transplant) physician.

Neurological complications in pediatric liver transplant recipients

INTRODUCTION

There is paucity of data on neurological complications (NCs) and its predisposing factors, in pediatric liver transplant (PLT) recipients.

METHODS

Records of seventy-one children who underwent LT between October 2018 and November 2019 were reviewed. Patients were categorized into group A: with NC and group B: without NC in the post-LT period. Various risk factors contributing to NC were studied.

RESULTS

In total, 15 (21.1%) had NC (group A) and 56 (78.9%) had no NC in the post-LT period. NC included cerebrovascular accident (n = 1), seizures (n = 5; 4 generalized, 1 focal), central pontine myelolysis (CPM) (n = 1), diaphragmatic palsy (n = 2), peripheral neuropathy (n = 1), extrapyramidal movements (n = 3), and encephalopathy beyond 96 h (n = 2). The median onset of NC was at 8.5 days post-LT (1-58 days). Ten (66.7%) patients in group A had grades 2-4 hepatic encephalopathy (HE) prior to LT. Eight (14.3%) patients in group B also had pre-LT neurological issues including HE in six, epilepsy and spastic diplegia in one each. On univariate analysis, pre-existing HE, high PELD/MELD score, pre-LT ventilation, pre-LT infection, higher day 1 post-operative bilirubin (all p < .05), and higher tacrolimus were found to predict post-operative NC whereas on multivariate analysis, pre-LT HE was the only predictive factor. Median follow-up was 15.5 months. Four patients died in each group (survival log-rank p = .369). All the surviving patients in group A (n = 11) fully recovered from the NC.

CONCLUSION

Pre-transplant HE was the single most significant predisposing factor for post-LT neurological complications.

2021 Clinical Update in Liver Transplantation

In 2021, the United States performed 9,236 liver transplantations, an increase of 3.7% from 2020. As the specialty of transplant anesthesiologist continues to grow, so does the body of evidence-based research to improve patient care. New technology in organ preservation offers the possibility of preserving marginal organs for transplant or improving the graft for transplantation. The sequalae of end-stage liver disease have wide-ranging consequences that affect neurologic outcomes of patients both during and after transplantation that anesthesiologists should monitor. Obesity presents several challenges for anesthesiologists. As an increasing number of patients with nonalcoholic steatohepatitis are listed for transplant, managing their multiple comorbidities can be challenging. Finally, the rebalanced hemostasis of end-stage liver disease can cause both bleeding and thrombus. Often, bleeding risks predominate as a concern, but anesthesiologists should be aware of risks of intracardiac thrombus and review therapeutic options for prevention and treatment.

Hyponatremia and Liver Transplantation: A Narrative Review

Hyponatremia is a common electrolyte disorder in patients with end-stage liver disease (ESLD) and is associated with increased mortality on the liver transplantation (LT) waiting list. The impact of hyponatremia on outcomes after LT is unclear. Ninety-day and one-year mortality may be increased, but the data are conflicting. Hyponatremic patients have an increased rate of complications and longer hospital stays after transplant. Although rare, osmotic demyelination syndrome (ODS) is a feared complication after LT in the hyponatremic patient. The condition may occur when the serum sodium (sNa) concentration increases excessively during or after LT. This increase in sNa concentration correlates with the degree of preoperative hyponatremia, the amount of intraoperative blood loss, and the volume of intravenous fluid administration. The risk of developing ODS after LT can be mitigated by avoiding large perioperative increases in sNa concentration . This can be achieved through measures such as carefully increasing the sNa pretransplant, and by limiting the intravenous intra- and postoperative amounts of sodium infused. SNa concentrations should be monitored regularly throughout the entire perioperative period.

Neurological Screening in Elderly Liver Transplantation Candidates: A Single Center Experience

Background: Cerebral small vessels disease (cSVD) is an age-related disorder and risk factor for stroke and cognitive/motor impairments. Neurological complications (NCs) are among the causes of adverse outcomes in older liver transplant recipients. This study sought to determine whether cSVD predicts acute NCs in over 65-year-old liver transplant patients. Methods: Data were collected, from a retrospective medical chart review, of 22 deceased donor liver transplant recipients aged 65 years or older with a pre-operative brain magnetic resonance imaging (MRI). We used the Fazekas score (0–3) as a quantitative measurement of the vascular lesion load seen in the MRI. We analyzed all post-operative acute NCs occurring during the hospital stay and any other non-NC. Results: cSVD was recognized in all patients. Neurological complications (NCs) occurred in 18.1% of patients with toxic-metabolic encephalopathy the most frequent diagnosis (13.64%). More severe cSVD was associated with seizures (p = 0.0362), longer hospital stay (p 0.0299), and disability (p 0.0134). In our elderly cohort, hepatic encephalopathy (HE) (p 0.0287) and ascites (p 0.0270) were predictors of NCs after liver transplantation. Ascites and/or variceal bleeding and severity of liver disease were associated with adverse post-operative outcomes. The small sample size limited the statistical analysis power. Conclusions: We present the preliminary data of a single-center retrospective study aimed at understanding the cSVD role on NCs and non-NCs after a liver transplantation in elderly patients. This would encourage a more appropriate multicenter prospective study that will definitely confirm if a neurological screening in old age liver transplant candidates is appropriate.

Hepatic Encephalopathy: From Metabolic to Neurodegenerative

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome of both acute and chronic liver disease. As a metabolic disorder, HE is considered to be reversible and therefore is expected to resolve following the replacement of the diseased liver with a healthy liver. However, persisting neurological complications are observed in up to 47% of transplanted patients. Several retrospective studies have shown that patients with a history of HE, particularly overt-HE, had persistent neurological complications even after liver transplantation (LT). These enduring neurological conditions significantly affect patient's quality of life and continue to add to the economic burden of chronic liver disease on health care systems. This review discusses the journey of the brain through the progression of liver disease, entering the invasive surgical procedure of LT and the conditions associated with the post-transplant period. In particular, it will discuss the vulnerability of the HE brain to peri-operative factors and post-LT conditions which may explain non-resolved neurological impairment following LT. In addition, the review will provide evidence; (i) supporting overt-HE impacts on neurological complications post-LT; (ii) that overt-HE leads to permanent neuronal injury and (iii) the pathophysiological role of ammonia toxicity on astrocyte and neuronal injury/damage. Together, these findings will provide new insights on the underlying mechanisms leading to neurological complications post-LT.

Evaluation of Clinical Neuropathy After Living Donor Liver Transplant

OBJECTIVES

Neurologic complications are more common in liver transplants than in other solid-organ transplants. One such neurologic complication, peripheral neuropathy, may cause functional limitations for recipients and have a negative effect on posttransplant quality of life. We aimed to examine the risk factors associated with the occurrence of clinical neuropathy after liver transplant and to investigate the frequency of sensory deficits.

MATERIALS AND METHODS

In this case-control study, we analyzed factors from medical records of 63 recipients who underwent living donor liver transplant during the period from January 2010 to December 2016. A neuropathy symptom score was assigned to identify the patients who had clinical neuropathy (case group) and the patients without clinical neuropathy (control group). Quantitative sensory testing was performed to measure the warm and cold detection thresholds, and the difference between the 2 groups was examined.

RESULTS

Compared with controls, patients with clinical neuropathy were older (61.0 vs 55.4 years; P = .028), had higher rates of diabetes (46.2% vs 16.0%; P = .03), and were taking antiviral agents against hepatitis B (100% vs 62%; P = .006). Patients with neuropathic symptoms had significantly increased frequencies of impairment of warm and cold detection thresholds. In addition, the greater severity of symptoms showed higher detection thresholds of warm (control, 40.7℃; mild-to-moderate, 43.8 ℃; severe, 46.0 ℃; P = .007) and cold (control, 28.8℃ ; mild-to-moderate, 27.0 ℃; severe, 21.8 ℃ ; P = .008).

CONCLUSIONS

Our findings show that older age, diabetes, and treatment with oral antiviral agents against hepatitis B virus were more likely to be associated with the occurrence of clinical neuropathy after liver transplant. Early awareness and careful monitoring are warranted.

Functional Improvement of Tacrolimus-Induced Parkinsonism With Amantadine After Liver Transplantation: A Case Report

ABSTRACT

Drug-induced parkinsonism is the most common type of drug-induced movement disorder, whose symptoms can decrease patient quality of life and reduce medication compliance. Tacrolimus is a routinely used immunosuppressant agent after liver transplantation, with a well-known neurotoxic profile. There have been rare reports of tacrolimus-induced parkinsonism, but its pharmacologic management and functional impact remain poorly characterized in the literature. We present a case of tacrolimus-induced parkinsonism in a 62-year-old man after a liver transplant, resulting in significant neurologic impairments and multiple barriers to hospital discharge. His tremor, rigidity, bradykinesia, gait dysfunction, dysphonia, and dysphagia significantly improved after starting low-dose amantadine, with increased functional independence that allowed for a safe discharge. This is the first case in the literature detailing tacrolimus-induced parkinsonism's functional impairments improving with amantadine monotherapy.

Intracerebral Hemorrhage Related With Penicillium Species Following Deceased-Donor Liver Transplant

Early or late posttransplant opportunistic infections are among the leading complications after liver transplant. The source of early posttransplant opportunistic infections is usually the patient, the implantation of an infected graft, contamination during a surgical procedure, or invasive interventions performed at the intensive care unit. A 10-year-old male patient with Wilson disease (Pediatric End-Stage Liver Disease Score of 42, Child-Pugh score of 12, total bilirubin 40 mg/dL, platelet count 55000/mL, hemoglobin level 6.3 g/dL, albumin level 1.7 g/dL, urinary copper level 4305 μ/24 h) was closely monitored in the pediatric intensive care unit of our liver transplantation center for care of a worsened general status. A deceased-donor liver transplant was performed using a right lobe liver graft (ex vivo split) obtained through the national organ sharing network. The patient developed rightward deviation of eyes and altered consciousness after the procedure and underwent cranial magnetic resonance imaging and computerized tomography examinations. The cranial magnetic resonance image, taken on the third postoperative day, revealed lesions consistent with embolic infarction, and the computed tomography scan, taken on the eighth day, showed intracerebral hemorrhage. Decompressive craniotomy, which included hematoma drainage and catheter placement, was performed. Culture and histopathologic examinations of the hematoma material revealed a Penicillium species of fungi. However, the patient died before a definitive diagnosis was made. The aim of this report is to raise awareness on early posttransplant opportunistic infections of the central nervous system presenting with intracranial hemorrhage following liver transplant.

Prevalence of cerebrovascular diseases that can cause hemorrhagic stroke in liver transplantation recipients: a 6-year comparative study with 24,681 healthy adults

BACKGROUND AND PURPOSE

Cerebrovascular diseases are a leading cause of mortality after liver transplantation (LT). The prevalence of potentially hemorrhagic cerebrovascular diseases (HCVDs) that could cause a hemorrhagic stroke in patients with severe liver diseases has not been reported. We aimed to analyze the underlying prevalence of HCVDs that could lead to hemorrhagic strokes in LT recipients compared with that in previously healthy controls.

METHODS

A retrospective study with 1,920 consecutive LT recipients and 24,681 adults who underwent a health checkup during the same period was conducted (January 2011-December 2016). The prevalence of cerebral aneurysms (CA), cerebral arteriovenous malformation (AVM), and cavernous malformation (CM) was evaluated using brain imaging, including computed tomography angiography, magnetic resonance imaging, magnetic resonance angiography, and digital subtraction angiography.

RESULTS

The prevalence of CA and CM were 3.1% and 0.5%, respectively, in the LT group and 3.8% and 0.4%, respectively, in the control group. According to the location of the cerebral artery, paraclinoid internal carotid artery aneurysms (odds ratio [OR] 0.440; P = 0.009) had a lower prevalence in LT recipients than in healthy controls. Anterior communicating artery (OR 3.080; P = 0.002) and superior cerebellar artery (OR 8.767; P = 0.017) aneurysms had a higher prevalence in the LT group than in the control. The prevalence of AVM was significantly higher in LT recipients (0.26%) than in healthy controls (0.06%).

CONCLUSION

LT recipients showed a different distribution of CA prevalence according to the locations of the cerebral artery and had a higher overall prevalence of AVM than previously healthy controls.

Approach to the liver transplant early postoperative period: an institutional standpoint

The liver transplant program in our center started in 1992, and post-liver transplant patients are still admitted to the intensive care unit. For the intensive care physician, a learning curve started then, skills were acquired, and a specific practice was established. Throughout this time, several concepts changed, improving the care of these patients. The practical approach varies between liver transplant centers, according to local specificities. Hence, we wanted to present our routine practice to stimulate the debate between dedicated teams, which can allow the introduction of new ideas and potentially improve each local standard of care.

Neuropraxia: An Underappreciated Morbidity of Liver Transplantation

BACKGROUND

Peripheral nerve injuries can be devastating complications of surgery, potentially resulting in severe functional disability and decreased quality of life. Long surgeries with considerable tissue manipulation, for example, liver transplantation, may present increased risk; however, neuropraxia in transplantation has not been well investigated.

MATERIALS AND METHODS

This is a retrospective study of all adult patients undergoing liver transplantation at a large academic center between January 2013 and December 2015. Descriptive analyses, logistic regressions, and forward selection procedures were used to determine the odds of developing neuropraxia and associated factors.

RESULTS

Of the 283 liver recipients, the mean age was 55.8 y, 35.1% were female, 65.6% were Caucasian, 8.9% were African American, 16.7% were Hispanic, and mean model for end-stage liver disease sodium score at transplant was 24.2 ± 10.9. The underlying etiology was alcohol (26.2%), hepatitis C (34.8%), nonalcoholic steatohepatitis (13.1%), and other (14.2%). The incidence of neuropraxia after liver transplantation was 8.3% (n = 25), with 60% (n = 16) upper extremities, 82% left sided, and 84% male. There was no difference in age, race, body mass index, hypertension, diabetes, hyperlipidemia, or smoking in those with neuropraxia versus those without. In multivariate analysis, neuropraxia was significantly associated with male gender, lower model for end-stage liver disease score, and longer duration of surgery (P < 0.05). Symptoms lasted median 5 d, with a wide range up to 187 d. Neuropraxia-specific treatment (physical therapy or medications) was required in 32% (n = 9).

CONCLUSIONS

Peripheral nerve injuries are an unexplored complication of liver transplantation. Although transient, a high number (8.2%) of patients developed neuropraxia, negatively affecting their ability for recovery. Exploration of mechanisms for minimizing risk and intraoperative detection and prevention should be considered to mitigate this complication.

Neurological Complications in Recipients after Living Donor Liver Transplantation

Background and Aim

Liver transplantation (LT) is the only curative treatment for patients with the end-stage liver disease. Amongst the complications post-LT, the neurological complications (NC) are particularly relevant. Our aim is to assess the incidence, risk factors and clinical presentation of NC in recipients after living donor liver transplantation.

Methods

Between November 2011 and December 2013, 149 patients were admitted to ICU in 3 different centres in Egypt after LDLT and were evaluated by full clinical examination, laboratory investigations, neuroimaging and the NC were observed over one month. This study was approved by the ethical committee of the National Research Center.

Results

46 recipients (30.9%) developed neurological complications. The most common neurological complication was Encephalopathy (14.1%) while the least were both central pontine myelinolysis and meningoencephalitis (0.7%). In addition, 7 patients developed cerebrovascular events (either ischemic or hemorrhagic strokes). Patients were then classified into uncomplicated and complicated subgroups according to the highest percentage of neurological complication symptoms. These were encephalopathy, delirium with agitation, hallucinations, and delusions.

Conclusion

A high incidence of neurological complications (30.9%) after LDLT was recorded, prolonging patient hospital stays. The most common complications were encephalopathy, delirium, hallucinations, delusions, and seizures some of which were drug related.

Neurotoxicity including posterior reversible encephalopathy syndrome after initiation of calcineurin inhibitors in transplanted methylmalonic acidemia patients: Two case reports and review of the literature

Introduction

New neurological symptoms in methylmalonic acidemia (MMA) patients after liver and/or kidney transplantation (LKT) are often described as metabolic stroke‐like‐events. Since calcineurin inhibitors (CNIs) are a well‐known cause of new neurological symptoms in non‐MMA transplanted patients, we investigated the incidence of CNI‐induced neurotoxicity including posterior reversible encephalopathy syndrome (PRES) in post‐transplanted MMA patients.

Methods

We report the two MMA patients treated with LKT in our center. Additionally, we performed a systematic review of case reports/series of post‐transplanted MMA patients and determined if CNI‐induced neurotoxicity/PRES was a likely cause of new neurological symptoms. Definite CNI‐induced neurotoxicity was defined as new neurological symptoms during CNI treatment with symptom improvement after CNI dose reduction/discontinuation. PRES was defined as CNI‐induced neurotoxicity with signs of vasogenic edema on brain magnetic resonance imaging (MRI)‐scan post‐transplantation.

Results

Our two MMA patients both developed CNI‐induced neurotoxicity, one had PRES. In literature, 230 transplanted MMA patients were identified. Neurological follow‐up was reported in 54 of them, of which 24 were excluded from analysis since no anti‐rejection medication was reported. Thirty patients, all using CNI, were included. Sixteen patients (53%) had no new neurological symptoms post‐transplantation and five patients (17%) had definite CNI neurotoxicity of whom two had PRES. Including our cases this results in a pooled incidence of 22% (7/32) definite CNI neurotoxicity and 9% PRES (3/32) in post‐transplanted MMA patients on CNI.

Conclusion

In MMA post‐transplanted patients with new neurological symptoms CNI‐induced neurotoxicity/PRES should be considered. Early recognition of CNI‐induced neurotoxicity is essential to initiate dose reduction/discontinuation of CNI to minimize persistent neurologic damage and improve outcome.

Concise one sentence take home message

In all post‐transplanted MMA patients with new neurological symptoms CNI‐induced neurotoxicity/PRES should be considered, and directly reducing the dose/discontinuation of CNI is essential.

Elevation of Preoperative Ammonia Level Is Not Associated With the Incidence of Postoperative Delirium in Patients with Liver Transplantation: A Propensity Score Matching Analysis

INTRODUCTION

The preoperative elevation of ammonia may be associated with postoperative neurologic complications. The aim of this study was to evaluate the effect of preoperative ammonia level on the incidence of delirium in patients after liver transplantation (LT).

MATERIALS AND METHODS

Patients (n = 260) who received LT from January 2010 to July 2017 in a single university hospital were retrospectively reviewed. The patients' demographic data, perioperative managements, and postoperative complications were assessed. Patients were divided into the following 2 groups: those who had a preoperative elevation (Group A, n = 158) and those with a normal range (Group C, n = 102). The cut-off value for a normal serum ammonia level in our hospital was defined as 32 μg/dL.

RESULTS

After propensity score matching, there was no difference in the incidence of delirium between the groups (P = .784). Delirium occurred in 8 of 68 (11.76%) patients in Group A and 7 of 68 (10.29%) patients in Group C after LT. In addition, there was no difference in the incidence of delirium between the groups, even patients were categorized based on serum ammonia levels into 3 groups as follows: < 32 μg/dL (28/158 [17.72%]), 32 to 65 μg/dL (28/158 [17.72%]), and >65 μg/dL (28/158 [17.72%]) (P = .134).

CONCLUSIONS

The preoperative serum ammonia level was not related with the incidence of postoperative delirium. The high elevation group, especially those with greater than 65 μg/dL of preoperative ammonia, was also not related with the incidence of delirium. However, our study is limited by its retrospective design, so future prospective studies are needed.

Educational needs in families of pediatric liver and kidney transplant recipients: A quality improvement project

Parents of pediatric liver and kidney transplant recipients were surveyed regarding their current education plans (eg, Individualized Education Program, 504), satisfaction with these plans, and interest in educational support from the psychosocial transplant team. Survey results indicate high rates of IEP and 504 plans, academic and related services, and accommodations among this population. The majority of parents/guardians reported satisfaction with their child's current school plan and did not report need for additional transplant team support specific to school services on the survey measure. However, other information highlights the importance for pediatric transplant teams to consider other ways to support this population's educational needs.

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 transplantation during infancy: No increased rate of neurological complications

pLT is a highly standardized therapy for children with end-stage liver disease and liver-based metabolic diseases. However, NCs after transplantation occur and especially younger children are considered as more vulnerable and susceptible to NCs. Up to now, detailed data particularly for the very young age group do not exist. We therefore retrospectively studied NCs in children after pLT under age of 24 months. Forty children aged between 19 days and 22 months were evaluated according to type of NC and potential risk factors. NCs occurred in 8/40 patients (20%). All experienced new-onset seizures and in 1/6 surviving patients, seizures evolved into epilepsy. Other NCs were intracerebral abscess (1/8 patients) and subdural hemorrhage (1/8 patients). The overall 3-year mortality rate was 10% (4/40 patients). Significant risk factors for NCs and therefore seizures were HAT (P = 0.020), total surgery time (P = 0.009), retransplantation (P < 0.001), period of catecholamine therapy (P = 0.024), period of mechanical ventilation (P = 0.014), and period of sedation (P = 0.010). Our study is the first to provide detailed information on NCs after pLT in children under 24 months of age. The incidence of NCs in this particular group of very young patients was not increased compared to previously published data of children of all ages. Main NC was new-onset seizure. In the surviving infants, prognosis of seizure was excellent and the risk of developing epilepsy was low. Even more, the occurrence of NCs did not significantly affect mortality or survival in this particular age group.

Tacrolimus-induced parkinsonism in a patient after liver transplantation - case report

BACKGROUND

Hepatic encephalopathy may manifest by a wide spectrum of neuropsychiatric symptoms, including cognitive impairment, seizures or extrapyramidal symptoms. The liver transplant can lead to improvement of the signs of encephalopathy but subsequent immunosuppressive treatment might possess pronounced neurotoxicity.

CASE PRESENTATION

We present a case report of a patient with chronic liver disease who developed signs of Parkinsonism after an orthotopic liver transplant, with consecutive immunosuppressant treatment with tacrolimus. Despite the improvement of liver functions due to the cytostatic treatment, a progressive worsening of neuropsychiatric symptoms associated with the presence of tremor was observed. Metabolic as well as endocrine dysfunctions were excluded as the primary causes of this condition. A brain CT did not reveal structural pathology. Signs of severe, symmetric Parkinsonism - with resting tremor, bradykinesia, rigidity and severe postural instability were observed. A brain MRI was performed with the presence of T2- hyperintensities in basal ganglia bilaterally. Tacrolimus blood concentration was elevated; hence the dose was reduced and later switched to less toxic sirolimus. Subsequently, clinical signs markedly improved after treatment modification. Improvement of clinical symptomatology after tacrolimus discontinuation supports the drug-induced etiology of this neurological condition.

CONCLUSIONS

Cytostatic treatment after solid organ transplantation often leads to signs of encephalopathy. If necessary, the dose of cytostatics needs to be reduced, or a less toxic agent must be chosen for the therapy. This modification is usually efficient with no further need for neurological intervention.

A systems-based approach to patient care after liver transplantation

Liver transplantation is a cure to many devastating acute and end-stage liver diseases. In the immediate postoperative period, patients are prone to graft, end-organ, and immunosuppressive complications. This article reviews the causes, diagnosis, and treatment of acute postoperative liver transplant complications.

Incidence, Etiology, and Outcomes of Altered Mental Status in the Perioperative Setting of Liver Transplantation

Background

We examined neurologic consultations for altered mental status in perioperative liver transplant patients to determine the overall incidence, to assess the presumed etiology and the data reviewed to determine that etiology, and to assess outcomes.

Methods

Retrospective chart review conducted for all 728 adult patients receiving orthotopic liver transplantation (OLT) between January 01, 2010, to June 30, 2014, with identification of 218 receiving neurology consults between 30 days pre-OLT and 90 days post-OLT, with review of all records necessary to determine initial findings and follow-up examination.

Results

Seventy-three consults for 69 patients were identified, with 27 felt to be altered since a procedure, 20 with sudden-onset altered mentation, and 26 with gradual or waxing-waning course. A single underlying etiology was identified in only 19 cases, with multiple factors involved in all others, with metabolic, toxic, infectious, and structural etiologies most often implicated. There was no statistically significant difference in outcome for those with altered mental status consults versus the total OLT population, though the sudden-onset presentation group did show significantly increased mortality rates.

Conclusions

This systematic study illustrates the variety of potential causes of altered mentation within the perioperative setting of liver transplantation. Workup including neuroimaging (preferably magnetic resonance imaging), infectious cultures, and expanded metabolic laboratory tests should be undertaken.

Perioperative Care of the Liver Transplant Patient

With the evolution of surgical and anesthetic techniques, liver transplantation has become "routine," allowing for modifications of practice to decrease perioperative complications and costs. There is debate over the necessity for intensive care unit admission for patients with satisfactory preoperative status and a smooth intraoperative course. Postoperative care is made easier when the liver graft performs optimally. Assessment of graft function, vigilance for complications after the major surgical insult, and optimization of multiple systems affected by liver disease are essential aspects of postoperative care. The intensivist plays a vital role in an integrated multidisciplinary transplant team.

Small-for-Size Syndrome: Bridging the Gap Between Liver Transplantation and Graft Recovery

In living donor liver transplantation, optimal graft size is estimated from values like graft volume/standard liver volume and graft/recipient body weight ratio but the final functional hepatic mass is influenced by other donor and recipient factors. Grafts with insufficient functional hepatic mass can produce a life-threatening condition with rapidly progressive liver failure called small-for-size syndrome (SFSS). Diagnosis of SFSS requires careful surveillance for signs of inadequate hepatocellular function, residual portal hypertension, and systemic inflammation that suggest rapidly progressive liver failure. Early diagnosis, symptom control, and addressing the cause of SFSS may prevent the need for retransplantation. With increased attention to avoiding donor risk, intensivists will be confronted with more SFSS recipients. In this review, we aim to outline a systematic approach to the medical management of patients with SFSS by providing a concise synopsis of general supportive care—neurological, cardiovascular, and renal support, mechanical ventilation, nutritional support, infection control, and tailored immunosuppression—with an aim to avoid end-organ damage or death and a review of current interventions including liver support devices, portal flow modulating drugs, and other experimental interventions that aim to preserve existing hepatic mass and improve conditions for hepatic regeneration. We examine evidence for SFSS interventions to provide the reader with information that may assist in clinical decision making. Points of controversy in care are purposefully highlighted to identify areas where additional experimental work is still needed. A full understanding of the pathophysiology of SFSS and measures to support liver regeneration will guide effective management.

Imaging spectrum of central nervous system complications of hematopoietic stem cell and solid organ transplantation

Neurologic complications are common after hematopoietic stem cell transplantation (HSCT) and solid organ transplantation (SOT) and affect 30-60% of transplant recipients. The aim of this article is to provide a practical imaging approach based on the timeline and etiology of CNS abnormalities, and neurologic complications related to transplantation of specific organs. The lesions will be classified based upon the interval from HSCT procedure: pre-engraftment period <30 days, early post-engraftment period 30-100 days, late post-engraftment period >100 days, and the interval from SOT procedure: postoperative phase 1-4 weeks, early posttransplant syndromes 1-6 months, late posttransplant syndromes >6 months. Further differentiation will be based on etiology: infections, drug toxicity, metabolic derangements, cerebrovascular complications, and posttransplantation malignancies. In addition, differentiation will be based on complications specific to the type of transplantation: allogeneic and autologous hematopoietic stem cells (HSC), heart, lung, kidney, pancreas, and liver. Thus, in this article we emphasize the strategic role of neuroradiology in the diagnosis and response to treatment by utilizing a methodical approach in the work up of patients with neurologic complications after transplantation.

Clinical Characteristics of Transplant-associated Encephalopathy in Children

We aimed to analyze characteristics of encephalopathy after both hematopoietic stem cell and solid organ pediatric transplantation. We retrospectively reviewed medical records of 662 pediatric transplant recipients (201 with liver transplantation [LT], 55 with heart transplantation [HT], and 67 with kidney transplantation [KT], 339 with allogeneic hematopoietic stem cell transplantation [HSCT]) who received their graft organs at Asan Medical Center between January 2000 and July 2014. Of the 662 patients, 50 (7.6%) experienced encephalopathy after transplantation. The incidence of encephalopathy was significantly different according to the type of organ transplant: LT, 16/201 (8.0%), HT, 13/55 (23.6%), KT, 5/67 (7.5%), and HSCT, 16/339 (4.7%) (P < 0.001). Drug-induced encephalopathy (n = 14) was the most common encephalopathy for all transplant types, but particularly after HSCT. Hypertensive encephalopathy was the most common after KT and HT, whereas metabolic encephalopathy was the most common after LT. The median time to encephalopathy onset also differed according to the transplant type: 5 days after KT (range 0-491 days), 10 days after HT (1-296 days), 49.5 days after HSCT (9-1,405 days), and 39 days after LT (1-1,092 days) (P = 0.018). The mortality rate among patients with encephalopathy was 42.0% (n = 21/50). Only 5 patients died of neurologic complications. Transplant-associated encephalopathy presented different characteristics according to the type of transplant. Specialized diagnostic approach for neurologic complications specific to the type of transplant may improve survival and quality of life in children after transplantation.

Neurologic emergencies in HIV-negative immunosuppressed patients

HIV-negative immunosuppressed patients comprise a heterogeneous group including transplant patients, patients undergoing treatment with immunosuppressors, uremic patients, alcoholics, undernourished patients, diabetics, patients on dialysis, elderly patients, and those diagnosed with severe or neoplastic processes. Epileptic seizures, focal neurologic signs, and meningoencephalitis are neurologic syndromes that require urgent action. In most of these situations, neuroimaging tests are necessary, but the findings can be different from those observed in immunocompetent patients in function of the inflammatory response. Infectious disease is the first diagnostic suspicion, and the identification of an opportunistic pathogen should be oriented in function of the type and degree of immunosuppression. Other neurologic emergencies include ischemic stroke, cerebral hemorrhage, neoplastic processes, and pharmacological neurotoxicity. This article reviews the role of neuroimaging in HIV-negative immunodepressed patients with a neurologic complication that requires urgent management.

Evaluation of Arteriovenous Shunting in Patients With End-Stage Liver Disease: Potential Role of Early Right Heart Catheterization

BACKGROUND

In patients with end-stage liver disease (ESLD), the presence of hypoxemia suggests the presence of intrapulmonary oxygen shunting (IPS) and/or transatrial shunting. Early identification of each is imperative to avoid potentially fatal peritransplantation complications and appropriately prioritize patients for liver transplantation (LT). The aim of this work was to compare the sensitivity of transthoracic echocardiography (TTE) and right heart catheterization (RHC) with intracardiac echocardiography (ICE) for identifying the etiologies of resting hypoxemia in patients with ESLD being evaluated for LT.

METHODS

Records of 28 patients with ESLD and resting hypoxemia who underwent TTE with bubble study and RHC/ICE were reviewed. Patients with a patent foramen ovale (PFO) were compared with non-PFO patients to determine diagnostic accuracy of TTE with bubble study versus RHC/ICE.

RESULTS

TTE with bubble study diagnosed PFO, IPS, and pulmonary hypertension (PH), respectively, with sensitivities of 46%, 41%, and 25% and specificities of 46%, 45%, and 80% compared with RHC/ICE. Although IPS detected by RHC/ICE was more common in patients without a PFO (92%), 5 patients with a PFO (33%) also had IPS (P = .002). Isolated PH was detected exclusively in patients with a PFO (5/15; 33%).

CONCLUSIONS

TTE with bubble study is neither sensitive nor specific to exclude a PFO in patients with ESLD. RHC/ICE is a safe and accurate diagnostic/interventional modality in this group of patients and is useful to diagnose other comorbidities, such as IPS and PH, that may coexist and contribute to resting hypoxemia.

Comprehensive risk assessment for early neurologic complications after liver transplantation

AIM: To determine risk factors for early neurologic complications (NCs) after liver transplantation from perspective of recipient, donor, and surgeon.

METHODS: In all, 295 adult recipients were enrolled consecutively between August 2001 and February 2014 from a single medical center in Taiwan. Any NC in the first 30 d post-liver transplantation, and perioperative variables from multiple perspectives were collected and analyzed. The main outcome was a 30-d NC. Generalized additive models were used to detect the non-linear effect of continuous variables on outcome, and to determine cut-off values for categorizing risk. Risk factors were identified using multiple logistic regression analysis.

RESULTS: In all, 288 recipients were included, of whom 142 (49.3%) experienced at least one NC, with encephalopathy being the most common 106 (73%). NCs prolonged hospital stay (35.15 ± 43.80 d vs 20.88 ± 13.58 d, P < 0.001). Liver recipients’ age < 29 or ≥ 60 years, body mass index < 21.6 or > 27.6 kg/m², Child-Pugh class C, history of preoperative hepatoencephalopathy or mental disorders, day 7 tacrolimus level > 8.9 ng/mL, and postoperative intra-abdominal infection were more likely associated with NCs. Novel risk factors for NCs were donor age < 22 or ≥ 40 years, male-to-male gender matching, graft-recipient weight ratio 0.9%-1.9%, and sequence of transplantation between 31 and 174.

CONCLUSION: NCs post- liver transplantation occurs because of factors related to recipient, donor, and surgeon. Our results provide a basis of risk stratification for surgeon to minimize neurotoxic factors during transplantation.

Prolonged Delirium With Catatonia Following Orthotopic Liver Transplant Responsive to Memantine

A 59-year-old man with nonalcoholic steatohepatitis cirrhosis underwent an orthotopic liver transplant and experienced a complicated postoperative course, including a prolonged delirium. After discharge to rehabilitation, he had 2 subsequent admissions for delirium. On the first readmission, the transplant team started the patient on risperidone and resumed treatment with sertraline. On his second readmission, neurology and psychiatry were consulted. On evaluation, the patient demonstrated signs of catatonia. On the basis of recommendations from psychiatry, the risperidone and sertraline were stopped, and the patient was started on mirtazapine. He failed to demonstrate improvement within the next 48 hours. Extensive work-up demonstrated a multifactorial etiology for his delirium, including calcineurin-related neuropsychiatric toxicity from tacrolimus leading to possible posterior reversible encephalopathy syndrome. However, after the initiation of memantine on hospital day 3-before the cessation of tacrolimus-the patient demonstrated marked improvement in mental status and motor symptoms. His magnetic resonance imaging, in addition to findings that raised concerns about posterior reversible encephalopathy syndrome, had demonstrated bilateral basal ganglia abnormalities on T1 imaging of uncertain origin. It is postulated that these findings served as predisposing factors for the patient's catatonic symptoms. Although it has been described in case reports following liver transplant, catatonia remains an underrecognized neuropsychiatric complication following liver transplant. This case demonstrates the effectiveness of memantine, an N-methyl-D-aspartic acid antagonist that decreases glutamine excitotoxicity, as a potential treatment for catatonia in postliver transplant patients.

Posterior Reversible Encephalopathy Syndrome After Transplantation: a Review

Posterior reversible encephalopathy syndrome (PRES) is a rare neurological disease. Recently, an increase in the number of transplantations has led to more cases being associated with PRES than what was previously reported. Calcineurin inhibitors (CNIs) are major risk factors for PRES in posttransplantation patients. The mechanisms of the development of PRES remain to be unclear. The typical clinical symptoms of PRES include seizures, acute encephalopathy syndrome, and visual symptoms. The hyperintense signal on fluid-attenuated inversion recovery image is the characteristic of the imaging appearance in these patients. In addition, other abnormal signals distributed in multiple locations are also reported in some atypical cases. Unfortunately, PRES is often not recognized or diagnosed too late due to complicated differential diagnoses, such as ischemic stroke, progressive multifocal leukoencephalopathy, and neurodegenerative diseases. Thus, this review emphasizes the importance of considering the possibility of PRES when neurological disturbances appear after solid organ transplantation or hematopoietic cell transplantation. Moreover, this review demonstrates the molecular mechanisms of PRES associated with CNIs after transplantation, which aims to help clinicians further understand PRES in the transplantation era.

Imaging panorama in postoperative complications after liver transplantation

The liver is the second most-often transplanted solid organ after the kidney, so it is clear that liver disease is a common and serious problem around the globe. With the advancements in surgical, oncological and imaging techniques, orthotopic liver transplantation has become the first-line treatment for many patients with end-stage liver disease. Ultrasound, and Doppler are the most economical and cost-effective imaging modalities for evaluating postoperative fluid collections and vascular complications. Computed tomography (CT) is used to confirm the findings of ultrasound and look for pulmonary complications. Magnetic resonance imaging (MRI) is used for the diagnosis of biliary complications, bile leaks and neurological complications. This article illustrates the imaging options for diagnosing the various complications that can be encountered in the postoperative period after liver transplantation.

Levetiracetam in the Treatment of Epileptic Seizures After Liver Transplantation

After liver transplantation, patients may develop seizures or epilepsy due to a variety of etiologies. The ideal antiepileptic drugs for these patients are those with fewer drug interactions and less hepatic toxicity. In this study, we present patients using levetiracetam to control seizures after liver transplantation. We retrospectively enrolled patients who received levetiracetam for seizure control after liver transplantation. We analyzed the etiology of liver failure that required liver transplantation, etiology of the seizures, outcomes of seizure control, and the condition of the patient after follow-up at the outpatient department. Hematological and biochemical data before and after the use of levetiracetam were also collected. Fifteen patients who received intravenous or oral levetiracetam monotherapy for seizure control after liver transplantation were enrolled into this study. All of the patients remained seizure-free during levetiracetam treatment. Two patients died during the follow-up, and the other 13 patients were alive at the end of the study period and all were seizure-free without neurological sequelae that interfered with their daily activities. No patients experienced liver failure or rejection of the donor liver due to ineffective immunosuppressant medications. The dosage of immunosuppressants did not change before and after levetiracetam treatment, and there were no changes in hematological and biochemical data before and after treatment. Levetiracetam may be a suitable antiepileptic drug for patients who undergo liver transplantation due to fewer drug interactions and a favorable safety profile.