Is minimal hepatic encephalopathy completely reversible following liver transplantation?

New clinical and pathophysiological perspectives defining the trajectory of cirrhosis

Traditionally, the complications of cirrhosis, namely variceal bleeding, ascites and hepatic encephalopathy, were thought to result predominantly from circulatory dysfunction and altered organ perfusion arising as a result of portal hypertension. Over the past 20 years, large, international prospective studies have indicated the importance of systemic inflammation and organ immunopathology as additional determinants of organ dysfunction in cirrhosis, which not only manifests in the liver, brain, circulation and the kidneys, but also the immune system, gut, muscles, adrenal glands, reproductive organs, heart and lungs. This review provides an overview of the traditional and emerging concepts around the initiation and maintenance of organ dysfunction in cirrhosis and proposes a new paradigm based upon a better understanding of acute decompensation of cirrhosis. The interaction between the traditional concepts and the emerging perspectives remains a matter of great interest and the basis for future research.

Bile-duct ligation renders the brain susceptible to hypotension-induced neuronal degeneration: Implications of ammonia

Hepatic encephalopathy (HE) is a debilitating neurological complication of cirrhosis. By definition, HE is considered a reversible disorder, and therefore HE should resolve following liver transplantation (LT). However, persisting neurological complications are observed in as many as 47% of LT recipients. LT is an invasive surgical procedure accompanied by various perioperative factors such as blood loss and hypotension which could influence outcomes post-LT. We hypothesize that minimal HE (MHE) renders the brain frail and susceptible to hypotension-induced neuronal cell death. Six-week bile duct-ligated (BDL) rats with MHE and respective SHAM-controls were used. Several degrees of hypotension (mean arterial pressure of 30, 60 and 90 mm Hg) were induced via blood withdrawal from the femoral artery and maintained for 120 min. Brains were collected for neuronal cell count and apoptotic analysis. In a separate group, BDL rats were treated for MHE with the ammonia-lowering strategy ornithine phenylacetate (OP; MNK-6105), administered orally (1 g/kg) for 3 weeks before induction of hypotension. Hypotension 30 and 60 mm Hg (not 90 mm Hg) significantly decreased neuronal marker expression (NeuN) and cresyl violet staining in the frontal cortex compared to respective hypotensive SHAM-operated controls as well as non-hypotensive BDL rats. Neuronal degeneration was associated with an increase in cleaved caspase-3, suggesting the mechanism of cell death was apoptotic. OP treatment attenuated hyperammonaemia, improved anxiety and activity, and protected the brain against hypotension-induced neuronal cell death. Our findings demonstrate that rats with chronic liver disease and MHE are more susceptible to hypotension-induced neuronal cell degeneration. This highlights MHE at the time of LT is a risk factor for poor neurological outcome post-transplant and that treating for MHE pre-LT might reduce this risk.

The influence of HE history, HE status and neuropsychological test type on learning ability in patients with cirrhosis

BACKGROUND & AIMS

Learning ability may be impaired in patients with a history of overt hepatic encephalopathy (OHE). The aim of this study was to compare performance on the first/second attempt at a series of tests.

METHODS

Two hundred and fourteen patients with cirrhosis were enrolled. On the day of study, 41% were classed as unimpaired, 38% as having minimal HE and 21% as having mild OHE; 58% had a history of OHE. Performance was compared between two versions of the trail-making test A (TMT-A), and between the first/second half of a simple/choice reaction time (sRT and cRT), and a working memory test (ScanRT).

RESULTS

Both patients with and without OHE history improved in TMT-A, sRT and ScanRT. Only patients with no OHE history improved in cRT. All patients, regardless of their HE status on the day of study, improved in TMT-A and sRT. Only patients with mild OHE on the day of study improved in cRT. Only unimpaired patients improved in ScanRT. When OHE history and HE status on the day of study were tested together, only HE status had an effect. The same held true when age, the Model for End Stage Liver Disease (MELD) and educational attainment were adjusted for.

CONCLUSIONS

HE status on the day of study and the type of neuropsychological test had an effect on learning ability in a well-characterized group of patients with cirrhosis.

What we know: the inflammatory basis of hepatic encephalopathy

Central Nervous System (CNS) degeneration appearing in patients with cirrhosis is responsible for cognitive and persistent motor impairments that lead to an important impact on life quality. Brain injury affects certain areas of the CNS that might affect two types of cells: neurons and astrocytes. The process leading to brain injury could be induced by portosystemic shunting accompanied by hyperammonemia and by the activation of peripheral inflammation, manifested as episodic encephalopathy. Hyperammonemia combined with a decrease on the BCA/AAA ratio induces alterations of energetic metabolism and the formation of free radicals in the CNS. This process would be stimulated by the activation of peripheral inflammatory mediators that could act on receptors of the blood brain barrier such as TLR4, activating inflammatory responses in the CNS. As a result, a persistent activation of microglia and an irreversible neuronal and astrocytic injury would be induced. A new knowledge of the mechanisms leading to brain injury in cirrhosis would develop protective strategies to correct changes of nitrogen metabolism and inflammation.

Reversibility of minimal hepatic encephalopathy following liver transplantation in Egyptian cirrhotic patients

AIM

To evaluate the reversibility of minimal hepatic encephalopathy (MHE) following liver transplantation (LT) in Egyptian cirrhotic patients.

METHODS

This prospective study included twenty patients with biopsy-proven liver cirrhosis listed for LT and twenty age- and sex-matched healthy control subjects. All underwent neuro-psychiatric examination, laboratory investigations, radiological studies and psychometric tests including trail making test A (TMT A), TMT B, digit symbol test and serial dotting test. The psychometric hepatic encephalopathy score (PHES) was calculated for patients to diagnose MHE. Psychometric tests were repeated six months following LT in the cirrhotic patient group.

RESULTS

Before LT, psychometric tests showed highly significant deficits in cirrhotic patients in comparison to controls (P < 0.001). There was a statistically significant improvement in test values in the patient group after LT; however, their values were still significantly worse than those of the controls (P < 0.001). The PHES detected MHE in 16 patients (80%) before LT with a median value of -7 ± 3.5. The median PHES value was significantly improved following LT, reaching -4.5 ± 5 (P < 0.001), and the number of patients with MHE decreased to 11 (55%). The pre-transplant model for end-stage liver disease (MELD) score ≥ 15 was significantly related to the presence of post-transplant MHE (P = 0.005). More patients in whom reversal of MHE was observed had a pre-transplant MELD score < 15.

CONCLUSION

Reversal of MHE in cirrhotic patients could be achieved by LT, especially in those with a MELD score < 15.

Minimal hepatic encephalopathy: A review

Minimal hepatic encephalopathy (MHE) is the earliest form of hepatic encephalopathy and can affect up to 80% of patients with liver cirrhosis. By definition, MHE is characterized by cognitive function impairment in the domains of attention, vigilance and integrative function, but obvious clinical manifestation are lacking. MHE has been shown to affect daily functioning, quality of life, driving and overall mortality. The diagnosis can be achieved through neuropsychological testing, recently developed computerized psychometric tests, such as the critical flicker frequency and the inhibitory control tests, as well as neurophysiological procedures. Event related potentials can reveal subtle changes in patients with normal neuropsychological performances. Spectral analysis of electroencephalography (EEG) and quantitative analysis of sleep EEG provide early markers of cerebral dysfunction in cirrhotic patients with MHE. Neuroimaging, in particular MRI, also increasingly reveals diffuse abnormalities in intrinsic brain activity and altered organization of functional connectivity networks. Medical treatment for MHE to date has been focused on reducing serum ammonia levels and includes non-absorbable disaccharides, probiotics or rifaximin. Liver transplantation may not reverse the cognitive deficits associated with MHE. We performed here an updated review on epidemiology, burden and quality of life, neuropsychological testing, neuroimaging, neurophysiology and therapy in subjects with MHE.

Persistence of cognitive impairment after resolution of overt hepatic encephalopathy

OBJECTIVES

Hepatic encephalopathy (HE) represents a spectrum of neurocognitive impairment seen in cirrhotic patients and is considered to be fully reversible with treatment; however, recent evidence suggests otherwise. This longitudinal study was carried out to evaluate the persistence of cognitive impairment in cirrhotics with prior overt HE (OHE) episode despite treatment.

METHODS

Of the 213 patients screened, 107 patients who met the eligibility criteria were enrolled and 102 patients completed the study (52 patients without prior OHE episode and 50 patients with prior OHE). All patients underwent psychometric hepatic encephalopathy score (PHES) evaluation at three separate visits (day 1, day 3, and between 30 and 60 days). A one-point improvement in PHES between the first and second evaluation was considered as a measure of learning.

RESULTS

Patients with a previous OHE episode showed learning impairment in PHES on repetition on day 3 (P=0.084), whereas patients without a previous OHE episode demonstrated learning effect (P<0.0001) irrespective of whether they had minimal HE (MHE) or not. Univariate analysis demonstrated that Child-Turcotte-Pugh score, lactulose and/or rifaximin therapy, the presence of MHE, and a previous OHE episode were associated with learning impairment. Multivariate analysis demonstrated that only the presence of a previous episode of OHE (adjusted odds ratio 38.398; 95% confidence interval 9.192-160.4; P<0.0001) significantly affected learning.

CONCLUSIONS

This study conclusively demonstrated learning impairment in cirrhotic patients with a previous episode of OHE despite normal mental status. Improvement in PHES on repetition may be a measure of learning.

Minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) is the earliest form of hepatic encephalopathy and can affect up to 80% of cirrhotic patients. By definition, it has no obvious clinical manifestation and is characterized by neurocognitive impairment in attention, vigilance and integrative function. Although often not considered to be clinically relevant and, therefore, not diagnosed or treated, MHE has been shown to affect daily functioning, quality of life, driving and overall mortality. The diagnosis of MHE has traditionally been achieved through neuropsychological examination, psychometric tests or the newer critical flicker frequency test. A new smartphone application (EncephalApp Stroop Test) may serve to function as a screening tool for patients requiring further testing. In addition to physician reporting and driving restrictions, medical treatment for MHE includes non-absorbable disaccharides (eg, lactulose), probiotics or rifaximin. Liver transplantation may not result in reversal of the cognitive deficits associated with MHE.

Comparison of the most favoured methods for the diagnosis of hepatic encephalopathy in liver transplantation candidates

OBJECTIVE

Hepatic encephalopathy (HE) is a common complication of liver insufficiency. While there is widespread acceptance of its importance, there is no consensus on how best to diagnose and monitor HE.

OBJECTIVE

To compare the four most favoured methods for the diagnosis of HE.

DESIGN

170 patients who were on the waiting list for liver transplantation as well as 86 healthy controls were included in the study. All patients and controls underwent the portosystemic encephalopathy syndrome test yielding the psychometric hepatic encephalopathy score (PHES), the repeatable battery for the assessment of neuropsychological status (RBANS), the inhibitory control test (ICT) and critical flicker frequency (CFF) measurement.

RESULTS

PHES and ICT targets had the best sensitivity (85.7% vs 85.7%) and specificity (96.5% vs 97.6%) for the diagnosis of overt HE. CFF showed inferior sensitivity (40.9%) for the diagnosis of HE and dependency from previous alcohol abuse (p=0.015). Multiple regression analysis showed that all test results apart from PHES were influenced by secondary diagnoses such as diabetes mellitus and renal insufficiency.

CONCLUSIONS

In the German population of patients awaiting liver transplantation, PHES is the most robust method for the diagnosis and follow-up of HE.

Encephalopathy and liver transplantation

Liver transplantation (LT) candidates experience frequently episodic or persistent hepatic encephalopathy. In addition, these patients can exhibit neurological comorbidities that contribute to cognitive impairment in the pre-transplant period. Assessment of the respective contribution of hepatic encephalopathy or comorbidities in the cognitive manifestations is critical to estimate the neurological benefits of restoring liver function. Magnetic resonance imaging and spectroscopy are useful to assess the impact of liver failure or comorbidities. This assessment is critical to decide liver transplant in difficult cases. In the early postoperative period, LT is commonly complicated by a confusional syndrome. The possible role of persisting hepatic encephalopathy in its development has not been clearly established. The origin is usually considered multifactorial and relates to complications following LT, such as infections, rejection, primary liver dysfunction, immunosuppressors, etc.… The diagnosis and treatment is based in the recognition of comorbidities and optimal care of metabolic disturbances. Several studies have demonstrated recovery of cognitive function after LT in patients that have exhibited hepatic encephalopathy. However, some deficits may persist specifically among patients with persistent HE. Other factors present before LT that contribute to a worse neuropsychological outcome after LT are diabetes mellitus and alcohol consumption. Long-term after LT, cognitive function may worsen in relation to vascular risk factors.

Nutritional management contributes to improvement in minimal hepatic encephalopathy and quality of life in patients with liver cirrhosis: A preliminary, prospective, open-label study

AIM

Problems in patients with minimal hepatic encephalopathy (MHE) include episodes such as falls and deficient driving skills, without any recognition of neurophysiological dysfunction. Patients with MHE are also more likely to develop overt hepatic encephalopathy. However, there is not yet any interventional strategy for MHE involving nutritional management. We conducted a preliminary study to investigate the proportion of positive MHE and the effects of nutritional management on MHE.

METHODS

Patients with viral liver cirrhosis and abnormal neuropsychological tests were included. Nutritional consultations were conducted periodically by a dietitian, who recommended 30-35 kcal with 1.0-1.5 g of protein/kg of ideal bodyweight/day. The primary end-point was to evaluate the proportion of patients who recovered from MHE. The secondary end-point was to evaluate the improvement in the patients' quality of life (QOL).

RESULTS

Thirty-two (30.1%) of 106 patients were diagnosed with MHE. Nineteen patients were enrolled in the study. Eleven of 19 patients became non-MHE after 4 weeks, and 13 of 19 patients (68.4%, P < 0.001) after 8 weeks. The mental summary scores were significantly improved at 8 weeks (P = 0.0413). Changes in albumin levels from week 0 to week 8 were 0.15 ± 0.16 g/dL in the improved MHE group and -0.28 ± 0.33 g/dL in the non-improved MHE group, which differ significantly (P = 0.0130).

CONCLUSION

Periodical nutritional management improved MHE and QOL. Improving the patient's nutritional condition may be one approach to treating MHE.

Extent of reversibility of hepatic encephalopathy following liver transplantation

Although hepatic encephalopathy (HE) is prevalent in the cirrhotic population, it has also been considered a potentially reversible condition. Liver transplantation represents the ultimate reversal of the decompensated cirrhotic state and should provide the best option for the reversibility of HE. However, the neurologic compromise associated with HE in the cirrhotic patient may not be completely reversible. Theories regarding fixed structural and reversible metabolic deficits as well as persistence of the hyperdynamic state with continued portosystemic shunting have been proposed to explain this lack of complete reversibility. Whether this remnant neurologic deficit is clinically significant remains unclear.

Hepatic encephalopathy is associated with posttransplant cognitive function and brain volume

Hepatic encephalopathy (HE) is a common complication of cirrhosis that is associated with brain atrophy and may participate in impaired cognitive function after liver transplantation. This study analyzes the relationship of HE with cognitive function and brain volume after transplantation. A total of 52 consecutive patients with cirrhosis (24 alcohol abuse, 24 prior HE, 14 diabetes mellitus) completed a neuropsychological assessment before liver transplantation and again, 6 to 12 months after transplantation. In 24 patients who underwent the posttransplant assessment, magnetic resonance imaging was performed in addition, with measurement of brain volume and relative concentration of N-acetylaspartate (NAA) and creatine/phosphocreatine (Cr), a neuronal marker, by magnetic resonance spectroscopy. Neuropsychological assessment prior to transplantation identified minimal HE in 28 patients. All cognitive indexes improved after liver transplantation, but 7 patients (13%) showed persistent mild cognitive impairment. Global cognitive function after transplantation was poorer in patients with the following variables before liver transplantation: alcohol etiology, diabetes mellitus, and HE. Brain volume after transplantation was smaller in patients with prior HE. Brain volume correlated to NAA/Cr values (r = 0.498, P = 0.013) and poor motor function (r = 0.41, P = 0.049). In conclusion, the association of HE with cognitive function and brain volume suggests that having experienced HE before liver transplantation impairs the posttransplantation neurological outcome.

Two-dimensional MR spectroscopy of minimal hepatic encephalopathy and neuropsychological correlates in vivo

PURPOSE

To evaluate regional cerebral metabolic and structural changes in patients with minimal hepatic encephalopathy (MHE) using two-dimensional (2D) MR spectroscopy (MRS) and T( (1) )-weighted MRI, to correlate the observed MR changes with neuropsychological (NP) test scores, and to compare the diagnostic accuracy of MRI, 2D MRS, and NP tests in discriminating between patients and healthy subjects.

MATERIALS AND METHODS

Thirty-three MHE patients and 30 healthy controls were investigated. The 2D localized correlated spectroscopy (L-COSY) was performed in the frontal and occipital brain on a 1.5 Tesla (T) MR scanner. The NP test battery included 15 tests, grouped into 6 cognitive domains. Globus pallidus signal intensities were calculated from T(1)-weighted images.

RESULTS

The 2D MRS showed significant differences in ratios of the following metabolite(s) peaks with respect to creatine (Cr): decreased myo-inositol (mI), choline (Ch), mICh, and increased (glutamate plus glutamine) (Glx) in patients compared with healthy subjects in both occipital and frontal lobes. Frontal lobe taurine also showed a decline in patients. The NP test results revealed declines in cognitive speed, motor function, executive function, and global cognitive status. Significant correlations were found between the altered metabolites and NP tests. Alteration in the mICh/Cr ratio was noted as a powerful discriminant between healthy subjects and the patients.

CONCLUSION

The study demonstrates that relative metabolite levels determined by 2D MRS, in particular mICh/Cr, provide the best diagnostic prediction for MHE. The results suggest that depletions of myo-inositol, choline and taurine with respect to creatine correlate with measures of neuropsychological impairment.

Neuropathological changes in the brain of pigs with acute liver failure

OBJECTIVE

Cerebral edema is a serious complication of acute liver failure (ALF), which may lead to intracranial hypertension and death. An accepted tenet has been that the blood-brain barrier is intact and that brain edema is primarily caused by a cytotoxic etiology due to hyperammonemia. However, the neuropathological changes in ALF have been poorly studied. Using a well characterized porcine model we aimed to investigate ultrastructural changes in the brain from pigs suffering from ALF.

MATERIALS AND METHODS

Sixteen female Norwegian Landrace pigs weighing 27-35 kg were randomised into two groups: ALF (n = 8) and sham operated controls (n = 8). ALF was induced with an end-to-side portacaval shunt followed by ligation of the hepatic arteries. Biopsies were harvested from three different areas of the brain (frontal lobe, cerebellum, and brain stem) following eight hours of ALF and analyzed using electron microscopy.

RESULTS

Profound perivascular and interstitial edema were found in all three areas. Disruption of pericytic and astrocytic processes were seen, reflecting breakdown/lesion of the blood-brain barrier in animals suffering from ALF. Furthermore, neurons and axons were edematous and surrounded by vesicles. Severe damage to Purkinje neuron (necrosis) and damaged myelin were seen in the cerebellum and brain stem, respectively. Biopsies from sham operated animals were normal.

CONCLUSIONS

Our data support the concept that vasogenic brain edema plays an important role in the development of intracranial hypertension in pigs with ALF.

Bile duct ligation in developing rats: temporal progression of liver, kidney, and brain damage

PURPOSE

Cholestatic liver disease may result in progressive end-stage liver disease and other extrahepatic complications. We explored the temporal progression of bile duct ligation (BDL)-induced cholestasis in developing rats, focusing on brain cognition and liver and kidney pathology, to elucidate whether these findings were associated with asymmetric dimethylarginine and oxidative stress alterations.

MATERIALS AND METHODS

Three groups of young male Sprague-Dawley rats were studied: one group underwent laparotomy (sham), another group underwent laparotomy and BDL for 2 weeks (BDL2), and a third group underwent laparotomy and BDL for 4 weeks (BDL4).

RESULTS

The effect of BDL on liver was represented by transforming growth factor beta1 levels and histology activity index scores, which were worse in the BDL4 rats than in the BDL2 rats. BDL4 rats also exhibited more severe spatial memory deficits than BDL2 rats. In addition, renal injury was more progressive in BDL4 rats than in BDL2 rats because BDL4 rats displayed higher Cr levels, elevated tubulointerstitial injury scores, neutrophil gelatinase-associated lipocalin, and symmetric dimethylarginine levels.

CONCLUSIONS

Our findings highlight the fact that young BDL rats exhibit similar trends of progression of liver, kidney, and brain damage. Further studies are needed to better delineate the nature of progression of organ damage in young cholestatic rats.

Persistence of cognitive impairment after resolution of overt hepatic encephalopathy

BACKGROUND & AIMS

In patients with cirrhosis, hepatic encephalopathy (HE) has acute but reversible as well as chronic components. We investigated the extent of residual cognitive impairment following clinical resolution of overt HE (OHE).

METHODS

Cognitive function of cirrhotic patients was evaluated using psychometric tests (digit symbol, block design, and number connection [NCT-A and B]) and the inhibitory control test (ICT). Improvement (reduction) in ICT lures and first minus second halves (DeltaL(1-2)) were used to determine learning of response inhibition. Two cross-sectional studies (A and B) compared data from stable cirrhotic patients with or without prior OHE. We then prospectively assessed cognitive performance, before and after the first episode of OHE.

RESULTS

In study A (226 cirrhotic patients), 54 had experienced OHE, 120 had minimal HE, and 52 with no minimal HE. Despite normal mental status on lactulose after OHE, cirrhotic patients were cognitively impaired, based on results from all tests. Learning of response inhibition (DeltaL(1-2) > or =1) was evident in patients with minimal HE and no minimal HE but was lost after OHE. In study B (50 additional patients who developed > or =1 documented OHE episode during follow-up), the number of OHE hospitalizations correlated with severity of residual impairment, indicated by ICT lures (r = 0.5, P = .0001), digit symbol test (r = -0.39, P = .002), and number connection test-B (r = 0.33, P = .04). In the prospective study (59 cirrhotic patients without OHE), 15 developed OHE; ICT lure response worsened significantly after OHE (12 before vs 18 after, P = .0003), and learning of response inhibition was lost. The 44 patients who did not experience OHE did not have deteriorations in cognitive function in serial testing.

CONCLUSIONS

In cirrhosis, episodes of OHE are associated with persistent and cumulative deficits in working memory, response inhibition, and learning.

Persistence of cognitive impairment after resolution of overt hepatic encephalopathy

BACKGROUND & AIMS

In patients with cirrhosis, hepatic encephalopathy (HE) has acute but reversible as well as chronic components. We investigated the extent of residual cognitive impairment following clinical resolution of overt HE (OHE).

METHODS

Cognitive function of cirrhotic patients was evaluated using psychometric tests (digit symbol, block design, and number connection [NCT-A and B]) and the inhibitory control test (ICT). Improvement (reduction) in ICT lures and first minus second halves (DeltaL(1-2)) were used to determine learning of response inhibition. Two cross-sectional studies (A and B) compared data from stable cirrhotic patients with or without prior OHE. We then prospectively assessed cognitive performance, before and after the first episode of OHE.

RESULTS

In study A (226 cirrhotic patients), 54 had experienced OHE, 120 had minimal HE, and 52 with no minimal HE. Despite normal mental status on lactulose after OHE, cirrhotic patients were cognitively impaired, based on results from all tests. Learning of response inhibition (DeltaL(1-2) > or =1) was evident in patients with minimal HE and no minimal HE but was lost after OHE. In study B (50 additional patients who developed > or =1 documented OHE episode during follow-up), the number of OHE hospitalizations correlated with severity of residual impairment, indicated by ICT lures (r = 0.5, P = .0001), digit symbol test (r = -0.39, P = .002), and number connection test-B (r = 0.33, P = .04). In the prospective study (59 cirrhotic patients without OHE), 15 developed OHE; ICT lure response worsened significantly after OHE (12 before vs 18 after, P = .0003), and learning of response inhibition was lost. The 44 patients who did not experience OHE did not have deteriorations in cognitive function in serial testing.

CONCLUSIONS

In cirrhosis, episodes of OHE are associated with persistent and cumulative deficits in working memory, response inhibition, and learning.

Neurocognitive-neurological complications of liver transplantation: a review

Neurological complications are common after liver transplantation (LT) and they are associated with a significant morbidity. Long-term effects of LT on cognitive and psychological outcomes are not clear. The objective of this study was to summarize the present knowledge on the neurological and cognitive complications of LT, resulting from a systematic review of the literature in the last 10 years. Several studies have investigated the incidence and the pathophysiology of neurological complications; in contrast, the knowledge of cognitive and psychological status after LT is poor. Currently, the effect of LT on mental performance is debated. Some studies have shown an improvement of cognitive function after OLTX and, at the same time, a persistence of different cognitive deficits. In addition, the quality of life (QoL) and the psychological status after LT seem to improve but LT recipients have significant deficiencies in most QoL domains. Consequently, future studies are necessary in order to investigate cognitive alterations and QoL in LT recipients.

Neuropsychological abnormalities in cirrhosis include learning impairment

BACKGROUND/AIMS

Minimal hepatic encephalopathy is a neurocognitive disorder secondary to liver failure that is characterized by a pattern of subcortical impairment. The most conspicuous neuropsychological abnormalities are on attention and psychomotor tests; memory has been inconsistently implicated. We designed a study to assess the presence of memory abnormalities in cirrhotic patients and the effects of liver transplantation.

METHODS

Ninety-seven cirrhotics without overt hepatic encephalopathy underwent neuropsychological assessment, including the Auditory Verbal Learning Memory Test. The results were compared to those of healthy controls (n=75) and the assessment was repeated at one year of follow-up (n=33) or after liver transplantation (n=23).

RESULTS

Cirrhotic patients exhibited multiple neuropsychological abnormalities, including several disturbances of the Auditory Verbal Learning memory test: learning, long-term memory and recognition. Abnormalities of long-term memory and recognition were corrected after adjusting for learning impairment. Memory abnormalities correlated to attention impairment and to parameters of liver function. Neuropsychological indexes following liver transplantation did not differ from controls. Repeated testing did not have a major effect on neuropsychological tests in healthy subjects and in non-transplanted cirrhotics.

CONCLUSIONS

Learning impairment is present in cirrhotic patients with neuropsychological abnormalities. This abnormality is consistent with attention deficit secondary to minimal hepatic encephalopathy.

Multidimensional assessment of neuro-psychiatric symptoms in patients with low-grade hepatic encephalopathy: A clinical rating scale

AIM: To evaluate the feasibility of a new clinical rating scale for a standardized assessment of cirrhosis-associated neuro-psychiatric symptoms.

METHODS: Forty patients with liver cirrhosis (LC, with or without low-grade hepatic encephalopathy) were invest-igated using a clinical neuro-psychiatric rating scale based on a comprehensive list of neurological, psychomotor, cognitive, affective, behavioral symptoms, and symptoms of disturbed bioregulation.

RESULTS: The analysis revealed that the majority of cirrhotic patients showed, besides characteristic neurological symptoms of hepatic encephalopathy, various psychomotor, affective and bioregulatory symptoms (disturbed sleep and sexual dysfunction). Patients were impaired in the following subscales: sleep and biorhythm disorder (75.0% of patients), Parkinsonoid symptoms (25.0%), affective symptoms (17.5%), and psychomotor retardation (12.5%). The increase of total neuro-psychiatric clinical score was significantly associated with the degree of hepatic enceph-alopathy.

CONCLUSION: This study suggests that a substantial number of patients with LC and low-grade hepatic encephalopathy manifest various clinical neuro-psychiatric symptoms. The use of a rating scale, which explores clinical dimensions of hepatic encephalopathy, would improve the management of patients with LC.

Preoperative optimization of patients with liver disease

PURPOSE OF REVIEW

Recent papers relevant to the preoperative evaluation and optimization of patients with severe liver disease will be discussed. The emphasis will be placed on cardiovascular, pulmonary, and renal complications. Other aspects such as preoperative management of hepatitis B and C, other infectious issues, and liver cancer will not be discussed because this rarely involves the anesthesiologist.

RECENT FINDINGS

Dobutamine stress echocardiography has been the cornerstone of cardiac evaluation of liver transplant candidates. Combining liver transplantation with cardiac procedures has been shown to be feasible. While mild hepatopulmonary syndrome is well-tolerated, severe hepatopulmonary syndrome carries a fairly high mortality rate. New treatment modalities of severe portopulmonary hypertension have been introduced, and may have advantages over epoprostenol administration. Hepatic hydrothorax requires similar therapy to ascites [repeated thoracentesis or paracentesis, and transjugular intrahepatic portosystemic shunt (TIPS)], but refractory hydrothorax may require other interventions. Hepatorenal syndrome may improve by increasing renal blood flow through the use of vasoconstrictors (vasopressin, norepinephrine) in combination with albumin administration. Interventional radiologists can now change the flow through an established TIPS. Hepatic encephalopathy may result in some irreversible changes in the brain. It remains difficult to predict whether a patient with acute fulminant failure will recover spontaneously. Support devices that include hepatocytes show early promising results. The coagulation changes in living donors are incompletely understood. Finally, autonomic neuropathy as a complication of severe liver disease results in more hemodynamic instability.

SUMMARY

Recent advances in preoperative evaluation and optimization are presented and discussed.

Diagnostic value of fine motor deficits in patients with low-grade hepatic encephalopathy

AIM: The role of motor dysfunction in early diagnosis of low-grade hepatic encephalopathy remains uncertain. We performed a pilot study to comparatively investigate the kinematic characteristics of small and large rapid alternating movements in patients with liver cirrhosis and low-grade hepatic encephalopathy.

METHODS: A kinematic analysis of alternating handwriting (7.5 mm) and large drawing movements (DM, 175 mm) was performed in 30 patients with liver cirrhosis (no hepatic encephalopathy: n = 10; minimal hepatic encephalopathy: n = 9; grade I hepatic encephalopathy: n = 11; healthy controls: n = 12). The correlation between kinematic parameters, clinical neuro-psychiatric symptoms of cerebral dysfunction and the grade of encephalopathy was investigated.

RESULTS: Both movement types, handwriting and drawing, were significantly slower in cirrhotic patients. In contrast to large DM, the deterioration of handwriting movements significantly correlated with the increase of symptoms of motor dysfunction and differentiated significantly within the group of cirrhosis patients corresponding to the degree of hepatic encephalopathy.

CONCLUSION: The deterioration of fine motor control is an important symptom of low-grade hepatic encephalopathy. The kinematic analysis of handwriting allows the quantitative analysis of alterations of motor function and is a possible tool for diagnostics and monitoring of motor dysfunction in patients with low-grade hepatic encephalopathy.

Portal hypertension

PURPOSE OF REVIEW

Report on significant advances in the pathophysiology, diagnosis, and management of the complications of portal hypertension that have occurred in the last year.

RECENT FINDINGS

The specific areas reviewed refer to experimental studies aimed at modifying the factors that lead to portal hypertension (increased intrahepatic vascular resistance and splanchnic vasodilatation) and recent advances in the diagnosis and management of the complications of portal hypertension. The specific complications reviewed in this paper are varices and variceal bleeding (primary prophylaxis, treatment of the acute episode, and secondary prophylaxis), ascites and some of its complications (hyponatremia, hepatic hydrothorax), hepatorenal syndrome, spontaneous bacterial peritonitis, and hepatic encephalopathy.

SUMMARY

Important studies, mostly prospective, regarding the management of the complications of portal hypertension are reviewed, including trials that demonstrate the value of the hepatic venous pressure gradient in predicting these complications, a trial of beta-blockers in patients with small varices, a randomized trial of transjugular intrahepatic portosystemic shunt using covered stents and another pilot study using this shunt in the treatment of hepatorenal syndrome, a trial of antibiotic prophylaxis in preventing early variceal rebleeding, and a trial of synbiotic therapy in hepatic encephalopathy. These trials will contribute to advancing the practice of hepatology and defining future research areas.