Yield of intermittent versus continuous EEG in comatose survivors of cardiac arrest treated with hypothermia.

INTRODUCTION: Electroencephalography (EEG) has a central role in the outcome prognostication in subjects with anoxic/hypoxic encephalopathy following a cardiac arrest (CA). Continuous EEG monitoring (cEEG) has been consistently developed and studied; however, its yield as compared to repeated standard EEG (sEEG) is unknown. METHODS: We studied a prospective cohort of comatose adults treated with therapeutic hypothermia (TH) after a CA. cEEG data regarding background activity and epileptiform components were compared to two 20 minute sEEG extracted from the cEEG recording (one during TH, and one in early normothermia). RESULTS: In this cohort, 34 recordings were studied. During TH, the agreement between cEEG and sEEG was 97.1% (95% CI: 84.6 - 99.9%) for background discontinuity and reactivity evaluation, while it was 94.1% (95% CI 80.3 - 99.2%) regarding epileptiform activity. In early normothermia, we did not find any discrepancies. Thus, concordance was very good during TH (kappa 0.83), and optimal during normothermia (kappa=1). The median delay between CA and the first EEG reactivity testing was 18 hours (range: 4.75 - 25) for patients with perfect agreement and 10 hours (range: 5.75 - 10.5) for the three patients in whom there were discordant findings (P=0.02, Wilcoxon). CONCLUSION: Standard intermittent EEG has comparable performance than continuous EEG both for variables important for outcome prognostication (EEG reactivity) and identification of epileptiform transients in this relatively small sample of comatose survivors of CA. This finding has an important practical implication, especially for centers where EEG resources are limited.

Congenital disorder of glycosylation type Id (CDG Id): phenotypic, biochemical and molecular characterization of a new patient.

Congenital disorders of glycosylation (CDG) are a family of multisystem inherited disorders caused by defects in the biosynthesis of N- or O-glycans. Among the many different subtypes of CDG, the defect of a mannosyltransferase encoded by the human ALG3 gene (chromosome 3q27) is known to cause CDG Id. Six patients with CDG Id have been described in the literature so far. We further delineate the clinical, biochemical, neuroradiological and molecular features of CDG Id by reporting an additional patient bearing a novel missense mutation in the ALG3 gene. All patients with CDG Id display a slowly progressive encephalopathy with microcephaly, severe psychomotor retardation and epileptic seizures. They also share some typical dysmorphic features but they do not present the multisystem involvement observed in other CDG syndromes or any biological marker abnormalities. Unusually marked osteopenia is a feature in some patients and may remain undiagnosed until revealed by pathological fractures. Serum transferrin screening for CDG should be extended to all patients with encephalopathy of unknown origin, even in the absence of multisystem involvement.

Characteristics of patients with chronic hepatitis C who develop hepatocellular carcinoma.

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is the most frequent form of primary liver cancer and chronic infection with hepatitis C virus is one of the main risk factors for HCC. This study analyses the characteristics of the patients with chronic hepatitis C participating in the Swiss Hepatitis C Cohort Study who developed HCC. METHODS: Analysis of the database of the Swiss Hepatitis C Cohort Study, a multicentre study that is being carried out in eight major Swiss hospitals since the year 2000. Patients with chronic hepatitis C and HCC were regrouped and compared to the patients without HCC. RESULTS: Among the 3,390 patients of the cohort, 130 developed an HCC. Age was one of the determining factors. Cirrhosis and its complications ascites and porto-systemic encephalopathy were associated with HCC. Males presented a higher risk for HCC than females. Alcohol consumption was associated with HCC. Diabetes mellitus was an important risk factor, especially in patients with low fibrosis. Patients with Hepatitis C genotype 2 had significantly less HCC than patients with other genotypes. A low socioeconomic status (income, education, profession) was associated with HCC. CONCLUSIONS: Beside the expected characteristics (age, gender, cirrhosis, alcohol), these data stress the role of diabetes mellitus and reveal the importance of low socioeconomic status as a risk factor for HCC in Swiss patients infected with hepatitis C virus. This vulnerable population should be closely monitored.

The neuro-ICU patient and electroencephalography paroxysms: if and when to treat.

PURPOSE OF REVIEW: To review recent clinical data and summarize actual recommendations for the management of electrographic seizures and status epilepticus in neuro-ICU patients. RECENT FINDINGS: Electrographic, 'nonconvulsive', seizures are frequent in neuro-ICU patients including traumatic brain injury, subarachnoid hemorrhage, intracerebral hemorrhage and hypoxic-ischemic encephalopathy. Continuous electroencephalography monitoring is thus of great potential utility. The impact of electrographic seizures on outcome however is not entirely established and it is also unclear what type of electroencephalography paroxysms require treatment and when and how exactly to treat them. Evidence from randomized studies is lacking and will not be available in the near future. Given robust animal and human evidence showing the potential negative impact of seizures on secondary cerebral damage and outcome, treatment of seizures appears reasonable, particularly if related to status epilepticus. On the contrary, over-aggressive antiepileptic therapy entails risks. The management of seizures should therefore be guided individually, based on the underlying cause, the severity of illness and patient comorbidities. SUMMARY: We provide a pragmatic approach for the management of electrographic seizures in neuro-ICU patients. International consensus guidelines on continuous electroencephalography monitoring and seizure therapy are needed and would represent the rationale for a future multicenter randomized trial.

Clinical correlates of frontal intermittent rhythmic delta activity (FIRDA).

Objectives: To investigate the clinical correlates of frontal intermittent rhythmic delta activity (FIRDA). Methods: we prospectively assessed all EEG studies recorded in our center over 3 months for the presence of frontal intermittent rhythmic delta activity (FIRDA). The FIRDA group was compared with a randomly selected control group from among EEGs recorded during the same period. Comparisons among FIRDA and non-FIRDA groups were performed using uni- and multi-variate analyses. Results: We found 36 patients with FIRDA among 559 EEG recordings (6%); the control group consisted of 80 subjects. While epilepsy was more frequent in the control group, structural brain lesions and encephalopathy were independently associated with the occurrence of FIRDA, but we could not identify any specific etiology. Asymmetric FIRDA was associated with an underlying brain lesion. Occasionally, FIRDA was recorded in otherwise healthy subjects during hyperventilation. Conclusion: FIRDA appears more common than previously reported, and is associated with a wide range of lesions and encephalopathic conditions. Significance: FIRDA occurrence should prompt investigations for toxic-metabolic disturbances and for structural lesions (particularly if asymmetric), but does not suggest an epileptic predilection.

Impaired chemical coupling of cerebral blood flow is compatible with intact neurological outcome in neonates with perinatal risk factors.

Early detection of pathophysiological factors associated with permanent brain damage is a major issue in neonatal medicine. The aim of our study was to evaluate the significance of the CO2 reactivity of cerebral blood flow (CBF) in neonates with perinatal risk factors. Fourteen ventilated neonates with perinatal risk factors (pathological cardiotocogramm, low cord pH, postpartal encephalopathy) were enrolled into this prospective study. The study was performed 18-123 h after birth. CBF was measured using the noninvasive intravenous 133Xe method. Two measurements were taken with a minimal PaCO2-difference of 5 mm Hg. From the two CBF values the CO2 reactivity was calculated. Outcome was evaluated 1 year after birth. The CBF values at a lower PaCO2 ranged from 6.6 to 115. 2 ml/100 g brain issue/min (median = 18.2) and at a higher PaCO2 level from 7.1 to 125.7 ml/100 g brain tissue/min (median = 18.75). The calculated CO2 reactivity ranged from -9.6 to 6.6% (median 1.1%) change in CBF/mm Hg change in PaCO2. CO2 reactivity correlated with lowest pH (r2 = 0.35, p = 0.02). Two infants died, one of neonatal sepsis, the other of heart failure. Neurological outcome at the age of 1 year was normal in 11 patients, 1 had severe cerebral palsy. From the 12 surviving patients the patient with severe neurological deficit showed the highest CBF values (125.7 ml/100 g/min). Impaired chemical coupling of cerebral blood flow is compatible with intact neurological outcome in neonates with perinatal risk factors. CO2 reactivity in these newborns correlates with the lowest pH and may reflect the severity of perinatal asphyxia.

Prognostic Importance of the Cuse of Renal Failure in Patients With Cirrhosis

BACKGROUND & AIMS: The prognostic value of the different causes of renal failure in cirrhosis is not well established. This study investigated the predictive value of the cause of renal failure in cirrhosis. METHODS: Five hundred sixty-two consecutive patients with cirrhosis and renal failure (as defined by serum creatinine 1.5 mg/dL on 2 successive determinations within 48 hours) hospitalized over a 6-year period in a single institution were included in a prospective study. The cause of renal failure was classified into 4 groups: renal failure associated with bacterial infections, renal failure associated with volume depletion, hepatorenal syndrome (HRS), and parenchymal nephropathy. The primary end point was survival at 3 months. RESULTS: Four hundred sixty-three patients (82.4%) had renal failure that could be classified in 1 of 4 groups. The most frequent was renal failure associated with infections (213 cases; 46%), followed by hypovolemia-associated renal failure (149; 32%), HRS (60; 13%), and parenchymal nephropathy (41; 9%). The remaining patients had a combination of causes or miscellaneous conditions. Prognosis was markedly different according to cause of renal failure, 3-month probability of survival being 73% for parenchymal nephropathy, 46% for hypovolemia-associated renal failure, 31% for renal failure associated with infections, and 15% for HRS (P .0005). In a multivariate analysis adjusted for potentially confounding variables, cause of renal failure was independently associated with prognosis, together with MELD score, serum sodium, and hepatic encephalopathy at time of diagnosis of renal failure. CONCLUSIONS: A simple classification of patients with cirrhosis according to cause of renal failure is useful in assessment of prognosis and may help in decision making in liver transplantation.

Diagnostic and prognostic value of cerebral 31P magnetic resonance spectroscopy in neonates with perinatal asphyxia.

The impact of depressed neonatal cerebral oxidative phosphorylation for diagnosing the severity of perinatal asphyxia was estimated by correlating the concentrations of phosphocreatine (PCr) and ATP as determined by magnetic resonance spectroscopy with the degree of hypoxic-ischemic encephalopathy (HIE) in 23 asphyxiated term neonates. Ten healthy age-matched neonates served as controls. In patients, the mean concentrations +/- SD of PCr and ATP were 0.99 +/- 0.46 mmol/L (1.6 +/- 0.2 mmol/L) and 0.99 +/- 0.35 mmol/L (1.7 +/- 0.2 mmol/L), respectively (normal values in parentheses). [PCr] and [ATP] correlated significantly with the severity of HIE (r = 0.85 and 0.9, respectively, p < 0.001), indicating that the neonatal encephalopathy is the clinical manifestation of a marred brain energy metabolism. Neurodevelopmental outcome was evaluated in 21 children at 3, 9, and 18 mo. Seven infants had multiple impairments, five were moderately handicapped, five had only mild symptoms, and four were normal. There was a significant correlation between the cerebral concentrations of PCr or ATP at birth and outcome (r = 0.8, p < 0.001) and between the degree of neonatal neurologic depression and outcome (r = 0.7). More important, the outcome of neonates with moderate HIE could better be predicted with information from quantitative 31P magnetic resonance spectroscopy than from neurologic examinations. In general, the accuracy of outcome predictability could significantly be increased by adding results from 31P magnetic resonance spectroscopy to the neonatal neurologic score, but not vice versa. No correlation with outcome was found for other perinatal risk factors, including Apgar score.

Limited role of the c-Jun N-terminal kinase pathway in a neonatal rat model of cerebral hypoxia-ischemia

D-JNKI1, a cell-permeable peptide inhibitor of the c-Jun N-terminal kinase (JNK) pathway, has been shown to be a powerful neuroprotective agent after focal cerebral ischemia in adult mice and young rats. We have investigated the potential neuroprotective effect of D-JNKI1 and the involvement of the JNK pathway in a neonatal rat model of cerebral hypoxia-ischemia. Seven-day-old rats underwent a permanent ligation of the right common carotid artery followed by 2h of hypoxia (8% oxygen). Treatment with D-JNKI1 (0.3mg/kg intraperitoneally) significantly reduced early calpain activation, late caspase-3 activation and, in the thalamus, autophagosome formation, indicating an involvement of JNK in different types of cell death: necrotic, apoptotic and autophagic. However the size of the lesion was unchanged. Further analysis showed that neonatal hypoxia-ischemia induced an immediate decrease in JNK phosphorylation (reflecting mainly P-JNK1) followed by a slow progressive increase (including P-JNK3 54kDa), whereas c-jun and c-fos expression were both strongly activated immediately after hypoxia-ischemia. In conclusion, unlike in adult ischemic models, JNK is only moderately activated after severe cerebral hypoxia-ischemia in neonatal rats and the observed positive effects of D-JNKI1 are insufficient to give neuroprotection. Thus, for perinatal asphyxia, D-JNKI1 can only be considered in association with other therapies.

Brain perfusion in sepsis.

Brain dysfunction is a frequent complication of sepsis, usually defined as "sepsis-associated encephalopathy" (SAE). Its pathophysiology is complex and related to numerous processes and pathways, while the exact mechanisms producing neurological impairment in septic patients remain incompletely elucidated. Alterations of the cerebral blood flow (CBF) may represent a key component for the development of SAE. Reduction of CBF may be caused by cerebral vasoconstriction, either induced by inflammation or hypocapnia. Endothelial dysfunction associated with sepsis leads to impairment of microcirculation and cerebral metabolic uncoupling that may further reduce brain perfusion so that CBF becomes inadequate to satisfy brain cellular needs. The natural autoregulatory mechanisms that protect the brain from reduced/ inadequate CBF can be impaired in septic patients, especially in those with shock or delirium, and this further contributes to cerebral ischemia if blood pressure drops below critical thresholds. Sedative agents alter cerebro-vascular reactivity and may significantly reduce CBF. Although disorders of brain perfusion and alteration of CBF and cerebral autoregulation are frequently observed in humans with sepsis, their exact role in the pathogenesis of SAE remains unknown. Brain perfusion can further become inadequate due to cerebral microcirculatory dysfunction, as evidenced in the experimental setting. Microvascular alterations can be implicated in the development of electrophysiological abnormalities observed during sepsis and contribute to neurological alterations in septic animals. The aim of this review is to provide an update on the pathophysiology of brain perfusion in sepsis, with a particular focus on human clinical investigation and novel tools for CBF monitoring in septic patients.

Predicting neurological outcome after cardiac arrest.

Purpose of reviewTherapeutic hypothermia and aggressive management of postresuscitation disease considerably improved outcome after adult cardiac arrest over the past decade. However, therapeutic hypothermia alters prognostic accuracy. Parameters for outcome prediction, validated by the American Academy of Neurology before the introduction of therapeutic hypothermia, need further update.Recent findingsTherapeutic hypothermia delays the recovery of motor responses and may render clinical evaluation unreliable. Additional modalities are required to predict prognosis after cardiac arrest and therapeutic hypothermia. Electroencephalography (EEG) can be performed during therapeutic hypothermia or shortly thereafter; continuous/reactive EEG background strongly predicts good recovery from cardiac arrest. On the contrary, unreactive/spontaneous burst-suppression EEG pattern, together with absent N20 on somatosensory evoked potentials (SSEP), is almost 100% predictive of irreversible coma. Therapeutic hypothermia alters the predictive value of serum markers of brain injury [neuron-specific enolase (NSE), S-100B]. Good recovery can occur despite NSE levels >33 mu g/l, thus this cut-off value should not be used to guide therapy. Diffusion MRI may help predicting long-term neurological sequelae of hypoxic-ischemic encephalopathy.SummaryAwakening from postanoxic coma is increasingly observed, despite early absence of motor signs and frank elevation of serum markers of brain injury. A new multimodal approach to prognostication is therefore required, which may particularly improve early prediction of favorable clinical evolution after cardiac arrest.

Detection of PrPres in genetically susceptible fetuses from sheep with natural scrapie

Scrapie is a transmissible spongiform encephalopathy with a wide PrPres dissemination in many non-neural tissues and with high levels of transmissibility within susceptible populations. Mechanisms of transmission are incompletely understood. It is generally assumed that it is horizontally transmitted by direct contact between animals or indirectly through the environment, where scrapie can remain infectious for years. In contrast, in utero vertical transmission has never been demonstrated and has rarely been studied. Recently, the use of the protein misfolding cyclic amplification technique (PMCA) has allowed prion detection in various tissues and excretions in which PrPres levels have been undetectable by traditional assays. The main goal of this study was to detect PrPres in fetal tissues and the amniotic fluid from natural scrapie infected ewes using the PMCA technique. Six fetuses from three infected pregnant ewes in an advanced clinical stage of the disease were included in the study. From each fetus, amniotic fluid, brain, spleen, ileo-cecal valve and retropharyngeal lymph node samples were collected and analyzed using Western blotting and PMCA. Although all samples were negative using Western blotting, PrPres was detected after in vitro amplification. Our results represent the first time the biochemical detection of prions in fetal tissues, suggesting that the in utero transmission of scrapie in natural infected sheep might be possible.

The impact of a register on the management of neonatal cooling in Switzerland.

BACKGROUND: Therapeutic hypothermia following hypoxic ischaemic encephalopathy in term infants was introduced into Switzerland in 2005. Initial documentation of perinatal and resuscitation details was poor and neuromonitoring insufficient. In 2011, a National Asphyxia and Cooling Register was introduced. AIMS: To compare management of cooled infants before and after introduction of the register concerning documentation, neuromonitoring, cooling methods and evaluation of temperature variability between cooling methods. STUDY DESIGN: Data of cooled infants before the register was in place (first time period: 2005-2010) and afterwards (second time period: 2011-2012) was collected with a case report form. RESULTS: 150 infants were cooled during the first time period and 97 during the second time period. Most infants were cooled passively or passively with gel packs during both time periods (82% in 2005-2010 vs 70% in 2011-2012), however more infants were cooled actively during the second time period (18% versus 30%). Overall there was a significant reduction in temperature variability (p < 0.001) comparing the two time periods. A significantly higher proportion of temperature measurements within target temperature range (72% versus 77%, p < 0.001), fewer temperature measurements above (24% versus 7%, p < 0.001) and more temperatures below target range (4% versus 16%, p < 0.001) were recorded during the second time period. Neuromonitoring improved after introduction of the cooling register. CONCLUSION: Management of infants with HIE improved since introducing the register. Temperature variability was reduced, more temperature measurements in the target range and fewer temperature measurements above target range were observed. Neuromonitoring has improved, however imaging should be performed more often.