Forewarning of hypotensive events using a Bayesian artificial neural network in neurocritical care.

Traumatically brain injured (TBI) patients are at risk from secondary insults. Arterial hypotension, critically low blood pressure, is one of the most dangerous secondary insults and is related to poor outcome in patients. The overall aim of this study was to get proof of the concept that advanced statistical techniques (machine learning) are methods that are able to provide early warning of impending hypotensive events before they occur during neuro-critical care. A Bayesian artificial neural network (BANN) model predicting episodes of hypotension was developed using data from 104 patients selected from the BrainIT multi-center database. Arterial hypotension events were recorded and defined using the Edinburgh University Secondary Insult Grades (EUSIG) physiological adverse event scoring system. The BANN was trained on a random selection of 50% of the available patients (n = 52) and validated on the remaining cohort. A multi-center prospective pilot study (Phase 1, n = 30) was then conducted with the system running live in the clinical environment, followed by a second validation pilot study (Phase 2, n = 49). From these prospectively collected data, a final evaluation study was done on 69 of these patients with 10 patients excluded from the Phase 2 study because of insufficient or invalid data. Each data collection phase was a prospective non-interventional observational study conducted in a live clinical setting to test the data collection systems and the model performance. No prediction information was available to the clinical teams during a patient's stay in the ICU. The final cohort (n = 69), using a decision threshold of 0.4, and including false positive checks, gave a sensitivity of 39.3% (95% CI 32.9-46.1) and a specificity of 91.5% (95% CI 89.0-93.7). Using a decision threshold of 0.3, and false positive correction, gave a sensitivity of 46.6% (95% CI 40.1-53.2) and specificity of 85.6% (95% CI 82.3-88.8). With a decision threshold of 0.3, > 15 min warning of patient instability can be achieved. We have shown, using advanced machine learning techniques running in a live neuro-critical care environment, that it would be possible to give neurointensive teams early warning of potential hypotensive events before they emerge, allowing closer monitoring and earlier clinical assessment in an attempt to prevent the onset of hypotension. The multi-centre clinical infrastructure developed to support the clinical studies provides a solid base for further collaborative research on data quality, false positive correction and the display of early warning data in a clinical setting.

Alteraciones neuropsicológicas y hallazgos neurorradiológicos en pacientes con conmoción cerebral postraumática. Resultados de un estudio piloto / Neuropsychological alterations and neuroradiological findings in patients with post-traumatic concussion: Results of a pilot study

INTRODUCCIÓN: Los traumatismos craneoencefálicos leves (TCE-L) han sido tradicionalmente considerados acontecimientos sin repercusiones cerebrales significativas, cuya sintomatología remite espontáneamente en unos días. Sin embargo, estos hechos son cada vez más cuestionados. Este estudio pretende objetivar la existencia de alteraciones cognitivas precoces en una serie de pacientes con TCE-L y relacionar los hallazgos con distintos marcadores de lesión cerebral. MÉTODOS: Estudio prospectivo de una cohorte de pacientes con un TCE-L valorados de forma consecutiva durante 12 meses. De un total de 1.144 pacientes, se seleccionó a 41 (3,7%) que habían presentado una conmoción cerebral. Además de la valoración clínica habitual y de la práctica de una tomografía computarizada (TC) cerebral, los pacientes fueron estudiados mediante un test estandarizado para síntomas posconmocionales en las primeras 24h después del TCE-L y al cabo de 1-2 semanas y, coincidiendo con la segunda valoración, mediante una batería neuropsicológica. Los resultados se compararon con los de un grupo de 28 voluntarios sanos de características parecidas. En 20 pacientes se practicó una resonancia magnética (RM) craneal. RESULTADOS: En este análisis exploratorio, la memoria y el aprendizaje verbal fueron las funciones cognitivas más afectadas después del TCE-L. Siete de los 20 pacientes con TC cerebral normal presentaron alteraciones estructurales visibles por RM, que en 2 casos fueron compatibles con la presencia de lesión axonal difusa. CONCLUSIONES: Los resultados de este estudio piloto sugieren la presencia de alteraciones cognitivas precoces y lesiones cerebrales estructurales en un porcentaje no despreciable de pacientes que han presentado una conmoción cerebral recuperada después de un TCE-L

INTRODUCTION: Mild traumatic brain injury (mTBI) has traditionally been considered to cause no significant brain damage since symptoms spontaneously remit after a few days. However, this idea is facing increasing scrutiny. The purpose of this study is to demonstrate the presence of early cognitive alterations in a series of patients with mTBI and to link these findings to different markers of brain damage. METHODS: We conducted a prospective study of a consecutive series of patients with mTBI who were evaluated over a 12-month period. Forty-one (3.7%) of the 1144 included patients had experienced a concussion. Patients underwent a routine clinical evaluation and a brain computed tomography (CT) scan, and were also administered a standardised test for post-concussion symptoms within the first 24 hours of mTBI and also 1 to 2 weeks later. The second assessment also included a neuropsychological test battery. The results of these studies were compared to those of a control group of 28 healthy volunteers with similar characteristics. Twenty patients underwent an MRI scan. RESULTS: Verbal memory and learning were the cognitive functions most affected by mTBI. Seven out of the 20 patients with normal CT findings displayed structural alterations on MR images, which were compatible with diffuse axonal injury in 2 cases. CONCLUSIONS: Results from this pilot study suggest that early cognitive alterations and structural brain lesions affect a considerable percentage of patients with post-concussion syndrome following mTBI

KidsBrainIT: A New Multi-centre, Multi-disciplinary, Multi-national Paediatric Brain Monitoring Collaboration.

OBJECTIVES: Validated optimal cerebral perfusion pressure (CPP) treatment thresholds in children do not exist. To improve the intensive care unit (ICU) management of the paediatric traumatic brain injury (TBI) population, we are forming a new paediatric multi-centre collaboration to recruit standardised ICU data for running and reporting upon models for assessing autoregulation and optimal CCP (CPPopt). MATERIALS AND METHODS: We are adapting the adult BrainIT group's approach to develop a new Paediatric Brain Monitoring and Information Technology Group (KidsBrainIT), which will include a repository to store prospectively collected high-resolution physiological, clinical, and outcome data. In the first phase of this project there are 7 UK Paediatric Intensive Care Units, 1 Spanish, 1 Belgium, and 1 Romanian Centre interested in participating. In subsequent phases, we plan to open recruitment to other centres both within Europe, US and abroad. We are collaborating with the Leuven Group and plan to use their LAx (low-frequency autoregulation index), DATACAR (dynamic adaptive target of active cerebral autoregulation), CPPopt and visualisation methodologies. We also plan to use the continuous diffuse optical monitoring and tomography technology developed in Barcelona as an acute surrogate end-point for optimising brain perfusion. This technology allows non-invasive continuous monitoring of deep tissue perfusion and oxygenation in adults but its clinical application in infants and children with TBI has not been studied previously. RESULTS: We report on the current status of setting up this new collaboration and also on pilot analyses in two centres which are the basis of our rationale for the need for a prospective validation study of CPPopt in children. Specifically, we demonstrated that CPPopt varied with time for each patient during their paediatric intensive care unit (PICU) stay, and the median overall CPPopt levels for children aged 2-6 years, 7-11 years and 12-16 years were 68.83, 68.09, and 72.17 mmHg respectively. Among survivors and patients with favourable outcome (GOS 4 and 5), there were significantly higher proportions with CPP monitoring time within CPPopt (p = 0.04 and p = 0.01 respectively). CONCLUSIONS: There is a need and an interest in forming a multi-centre PICU collaboration for acquiring data and performing analyses for determining validated CPPopt thresholds in the paediatric TBI population. KidsBrainIT is being formed to meet that need.

Neuropsychological alterations and neuroradiological findings in patients with post-traumatic concussion: Results of a pilot study. / Alteraciones neuropsicológicas y hallazgos neurorradiológicos en pacientes con conmoción cerebral postraumática. Resultados de un estudio piloto.

INTRODUCTION: Mild traumatic brain injury (mTBI) has traditionally been considered to cause no significant brain damage since symptoms spontaneously remit after a few days. However, this idea is facing increasing scrutiny. The purpose of this study is to demonstrate the presence of early cognitive alterations in a series of patients with mTBI and to link these findings to different markers of brain damage. METHODS: We conducted a prospective study of a consecutive series of patients with mTBI who were evaluated over a 12-month period. Forty-one (3.7%) of the 1144 included patients had experienced a concussion. Patients underwent a routine clinical evaluation and a brain computed tomography (CT) scan, and were also administered a standardised test for post-concussion symptoms within the first 24hours of mTBI and also 1 to 2 weeks later. The second assessment also included a neuropsychological test battery. The results of these studies were compared to those of a control group of 28 healthy volunteers with similar characteristics. Twenty patients underwent an MRI scan. RESULTS: Verbal memory and learning were the cognitive functions most affected by mTBI. Seven out of the 20 patients with normal CT findings displayed structural alterations on MR images, which were compatible with diffuse axonal injury in 2 cases. CONCLUSIONS: Results from this pilot study suggest that early cognitive alterations and structural brain lesions affect a considerable percentage of patients with post-concussion syndrome following mTBI.

[Atypical ganglioglioma with BRAF V600E mutation: a case report and review of the literature]. / Ganglioglioma atipico con mutacion de BRAF V600E: caso clinico y revision de la bibliografia.

INTRODUCTION: Gangliogliomas are rare tumours that affect young patients, appear predominantly in the temporal lobe and usually begin with epileptic seizures. Histologically they have a grade I of malignancy, with an anaplastic form that is catalogued as grade III in the 2007 WHO classification. Yet, there are tumours that do not meet the criteria of either grade and which offer clear prognostic differences with respect to those of grade I. These tumours would be atypical gangliogliomas (grade II), which are not considered in this classification. From the molecular point of view, the best known alteration in gangliogliomas is the BRAF V600E mutation, which worsens the prognosis of the lesion. The possible use of treatments targeted towards this mutated protein is especially relevant in this disorder. CASE REPORT: A 21-year-old male, who had undergone surgery due to a ganglioglioma on two occasions. The neuro-pathological examination revealed histological features consistent with an intermediate grade of malignancy (grade II), with positive BRAF mutation. CONCLUSIONS: The case presented here, together with those previously reported in the literature, reopens the debate on the definition of gangliogliomas in the 2007 WHO classification, and lends support to the fact that the next classification should again include atypical gangliogliomas (grade II), together with possible genetic mutations and molecular disorders.

TITLE: Ganglioglioma atipico con mutacion de BRAF V600E: caso clinico y revision de la bibliografia.Introduccion. Los gangliogliomas son tumores raros que afectan a pacientes jovenes, aparecen predominantemente en el lobulo temporal y suelen comenzar con crisis epilepticas. Histologicamente corresponden a un grado I de malignidad, con una forma anaplasica catalogada como de grado III en la clasificacion de la Organizacion Mundial de la Salud (OMS) de 2007. Sin embargo, existen tumores que no cumplen criterios de uno u otro grado y que presentan claras diferencias pronosticas respecto a los de grado I. Estos tumores corresponderian a gangliogliomas atipicos (grado II), no contemplados en la citada clasificacion. Desde el punto de vista molecular, la alteracion mas conocida en los gangliogliomas es la mutacion de BRAF V600E, que confiere peor pronostico a la lesion. La posibilidad de utilizar tratamientos dirigidos a esta proteina mutada otorga una especial relevancia a esta alteracion. Caso clinico. Varon de 21 años, intervenido de un ganglioglioma en dos ocasiones, en el que el examen neuropatologico objetivo caracteristicas histologicas compatibles con un grado de malignidad intermedio (grado II) con mutacion positiva a BRAF. Conclusiones. El caso presentado, junto con los descritos previamente en la bibliografia, reabre las controversias sobre la definicion de los gangliogliomas en la clasificacion de la OMS de 2007, y apoya el hecho de que la proxima clasificacion de la OMS deberia volver a incluir los gangliogliomas atipicos (grado II) e integrar posibles mutaciones geneticas y alteraciones moleculares.

Epilepsy in patients with malignant middle cerebral artery infarcts and decompressive craniectomies.

UNLABELLED: Patients with malignant middle cerebral artery (MCA) infarctions who have undergone craniectomy are susceptible to the development of vascular epilepsy. Our objective was to study the factors that might influence the occurrence of seizures in this group of patients. MATERIALS AND METHODS: All patients who developed malignant MCA infarction and had undergone decompressive craniectomy in our center between November 2002 and January 2014 were evaluated. In the subsequent follow-up, we evaluated the clinical outcomes and attempted to identify the factors that were related to the occurrence of seizures. RESULTS: We evaluated a total of 80 patients. The median time at which the craniectomy was performed was 40.5h after the stroke. Seizures occurred in 47.5% of all patients. The mortality rate within the first week was 16%, and of those who survived 53.7% developed seizures; 9% of these seizures were acute symptomatic, and 44.8% were remote. The median onset of remote seizures was seven months, and the majority of these were motor seizures with generalization. Notably, the patients with seizures exhibited longer delays from stroke to craniectomy, greater involvements of the temporal lobe and a higher rate of post-craniectomy recanalization of the occluded artery. Regarding the timing of the surgeries, a significantly greater proportion of those who underwent surgery more than 42h after the stroke developed epilepsy (p=0.004). Logistic regression revealed that only prolonged delay (>42h) independently predicted the development of epilepsy (OR 5.166; IC 95% 1.451-18.389; p=0.011). CONCLUSIONS: More than half of patients with malignant MCA infarcts who underwent decompressive craniectomy developed epilepsy. The occurrence of seizures in these patients was related to the delay to the performance of the craniectomy.

Brainstem auditory and somatosensory evoked potentials: a methodological study to evaluate the reproducibility of two devices.

We aimed to determine whether statistical significant differences exist between the sets of results obtained from two devices used in our department for measuring brainstem auditory evoked potentials (BAEPs) and somatosensory evoked potentials (SEPs). We obtained BAEP and median and posterior tibial nerve SEP values bilaterally in ten healthy subjects. The tests were performed on the same subject using two devices consecutively. The equipment consisted of a Nicolet Viking-IV (Nicolet, Madison, WI, USA) and a Viking Select (Viasys Healthcare, Madison, WI, USA), and the same recording electrodes and stimulator (auditory and electrical) were used without modifying any postural position of the subject. The stimuli and recording parameters were the same for both devices. We obtained 20 sets of data for each type of test. The Bland­Altman plots as well as the one-sample t-test or Wilcoxon signed rank test were used to compare data between the two groups of data sets. We found no significant differences between the sets of values obtained with the two devices. Our analysis indicates that the two devices are equal in recording all different variables of BAEP and SEP, which allows us to combine the BAEP and SEP data obtained from the two devices for follow-up studies involving quantitative statistical methods. This study received institutional approval (protocol number PRAG-154/2013).

Fenómenos de despolarización cortical propagada en los pacientes con lesiones cerebrales traumáticas e isquémicas. Resultados de un estudio piloto / Cortical spreading depolarization phenomena in patients with traumatic and ischemic brain injuries. Results of a pilot study

OBJETIVOS: Determinar la frecuencia y duración de episodios de despolarización cortical propagada (CSD y CSD-like) en pacientes con lesiones por traumatismo craneoencefálico (TCE) e infartos malignos de la arteria cerebral media (IMACM) que requirieron craneotomía. DISEÑO: Estudio descriptivo-observacional desarrollado durante 19 meses. Ámbito: Pacientes neurocríticos. PACIENTES: Estudio realizado en 16 pacientes (9 IMACM y 7 TCE graves) que requirieron tratamiento quirúrgico. INTERVENCIONES: Colocación de una tira de 6 electrodos en el córtex perilesional para el registro continuo de electrocorticografía (ECoG). Variables de interés principales: En todos los casos se determinó la hora, el número y la duración de los episodios de CSD y CSD-like detectados. RESULTADOS: De los 16 registros de ECoG analizados, 9 presentaron fenómenos CSD y CSD-like, de duración y frecuencias muy variables. CONCLUSIONES: Los episodios de CSD y CSD-like se detectan con frecuencia en el córtex en las regiones de penumbra isquémica y/o traumática de pacientes con un IMACM que han requerido craniectomía descompresiva o afectos de un TCE con contusiones cerebrales

OBJECTIVES: To determine the frequency and duration of cortical spreading depolarization (CSD) and CSD-like episodes in patients with traumatic brain injury (TBI) and malignant middle cerebral artery infarction (MMCAI) requiring craniotomy. DESIGN: A descriptive observational study was carried out during 19 months. SETTING: Neurocritical patients. PATIENTS: Sixteen patients were included: 9 with MMCAI and 7 with moderate or severe TBI, requiring surgical treatment. Interventions A 6-electrode subdural electrocorticographic (ECoG) strip was placed onto the perilesional cortex. MAIN VARIABLES OF INTEREST: An analysis was made of the time profile and the number and duration of CSD and CSD-like episodes recorded from the ECoGs. RESULTS: Of the 16 patients enrolled, 9 presented episodes of CSD or CSD-like phenomena, of highly variable frequency and duration. CONCLUSIONS: Episodes of CSD and CSD-like phenomena are frequently detected in the ischemic penumbra and/or traumatic cortical regions of patients with MMCAI who require decompressive craniectomy or of patients with contusional TBI

Alteraciones del sueño, un síndrome olvidado en los pacientes con malformación de Chiari tipo I / Sleep disturbance: a forgotten syndrome in patients with Chiari I malformation

Introducción: La malformación de Chiari tipo I (MC-I) se caracteriza por la existencia de una ectopia de las amígdalas del cerebelo que se sitúan por debajo del foramen mágnum, lo que puede asociarse a fenómenos compresivos del tronco del encéfalo, de la médula espinal alta y de los pares craneales. Las manifestaciones clínicas más frecuentes suelen ser las cefaleas occípitonucales y los mareos, aunque el cortejo sintomático puede ser muy extenso. Sin embargo, un aspecto menos conocido es la repercusión de la malformación sobre las alteraciones respiratorias nocturnas y los trastornos del sueño. Fuentes: MEDLINE e información de pacientes con MC-I valorados en los servicios de neurocirugía y neurofisiología del Hospital Universitario Vall d’Hebron. Desarrollo: Artículo de revisión realizado a partir del análisis de todos los estudios publicados en MEDLINE a partir del año 1966, localizados a través del motor de búsqueda PubMed, utilizando combinaciones de las palabras clave: «Chiari malformation» o «Arnold-Chiari malformation» y «sleep apnea» o «sleep disorders». Conclusiones: Los pacientes con una MC-I presentan una mayor prevalencia de trastornos del sueño que la población general. En algunos estudios el 50% de los pacientes con MC-I presentan un síndrome de apnea-hipopnea del sueño (SAHS), habiéndose descrito incluso casos de muerte súbita probablemente relacionados con estos fenómenos. Estos resultados recomiendan incluir el análisis de los parámetros respiratorios nocturnos en el estudio de los pacientes con MC-I. Identificar la presencia de un SAHS contribuye a optimizar el tratamiento de estos pacientes, mejorando la calidad de vida y su pronóstico

Introduction: Chiari type I malformation (CM-I) is characterised by caudal ectopia of the cerebellar tonsils through the foramen magnum. This is associated with brain stem, high spinal cord, and cranial nerve compression phenomena. The most frequent symptoms are occipital headaches and dizziness. Less well-known symptoms are sleep disorders and nocturnal respiratory abnormalities. Sources: MEDLINE and information from patients evaluated at the Neurosurgery and ClinicalNeurophysiology Departments at Hospital Universitario Vall d’Hebron. Development: Review article based on data obtained from MEDLINE articles since 1966, using combinations of the following keywords: «Chiari malformation» or «Arnold-Chiari malformation» and «sleep apnea» or «sleep disorders». Conclusions: CM-I patients show a higher prevalence of sleep disorders than that observed in the general population. Some studies report a 50% prevalence of sleep apnea-hypopnea syndrome (SAHS), probably associated with sudden death in some cases. These results support analysing sleep respiratory parameters in theses patients. Identifying SAHS symptoms may help optimise treatment, thereby improving quality of life and prognosis

Sleep disturbance: a forgotten syndrome in patients with Chiari I malformation.

INTRODUCTION: Chiari type I malformation (CM-I) is characterised by caudal ectopia of the cerebellar tonsils through the foramen magnum. This is associated with brain stem, high spinal cord, and cranial nerve compression phenomena. The most frequent symptoms are occipital headaches and dizziness. Less well-known symptoms are sleep disorders and nocturnal respiratory abnormalities. SOURCES: MEDLINE and information from patients evaluated at the Neurosurgery and Clinical Neurophysiology Departments at Hospital Universitario Vall d'Hebron. DEVELOPMENT: Review article based on data obtained from MEDLINE articles since 1966, using combinations of the following keywords: «Chiari malformation¼ or «Arnold-Chiari malformation¼ and «sleep apnea¼ or «sleep disorders¼. CONCLUSIONS: CM-I patients show a higher prevalence of sleep disorders than that observed in the general population. Some studies report a 50% prevalence of sleep apnea-hypopnea syndrome (SAHS), probably associated with sudden death in some cases. These results support analysing sleep respiratory parameters in theses patients. Identifying SAHS symptoms may help optimise treatment, thereby improving quality of life and prognosis.

[Cortical spreading depolarization phenomena in patients with traumatic and ischemic brain injuries. Results of a pilot study]. / Fenómenos de despolarización cortical propagada en los pacientes con lesiones cerebrales traumáticas e isquémicas. Resultados de un estudio piloto.

OBJECTIVES: To determine the frequency and duration of cortical spreading depolarization (CSD) and CSD-like episodes in patients with traumatic brain injury (TBI) and malignant middle cerebral artery infarction (MMCAI) requiring craniotomy. DESIGN: A descriptive observational study was carried out during 19 months. SETTING: Neurocritical patients. PATIENTS: Sixteen patients were included: 9 with MMCAI and 7 with moderate or severe TBI, requiring surgical treatment. INTERVENTIONS: A 6-electrode subdural electrocorticographic (ECoG) strip was placed onto the perilesional cortex. MAIN VARIABLES OF INTEREST: An analysis was made of the time profile and the number and duration of CSD and CSD-like episodes recorded from the ECoGs. RESULTS: Of the 16 patients enrolled, 9 presented episodes of CSD or CSD-like phenomena, of highly variable frequency and duration. CONCLUSIONS: Episodes of CSD and CSD-like phenomena are frequently detected in the ischemic penumbra and/or traumatic cortical regions of patients with MMCAI who require decompressive craniectomy or of patients with contusional TBI.

Impact of chronic kidney disease on the risk of clinical outcomes in patients with cancer-associated venous thromboembolism during anticoagulant treatment.

BACKGROUND: Information on recurrent venous thromboembolic events (VTEs) and major bleeding risks during anticoagulant treatment in patients with cancer-associated VTEs and chronic kidney disease (CKD) is scarce, although it is of relevance in establishing better tailored management strategies in these patients. OBJECTIVES: We compared risks of recurrent VTEs and major bleeds in cancer-associated VTE patients with and without CKD. METHODS: A total of 1684 patients diagnosed with a cancer-associated VTE between 2001 and 2011 were followed for 180 days after VTE diagnosis. Patients were treated mainly with low-molecular-weight heparin (LMWH) or vitamin-K antagonists (VKA). Primary outcomes were recurrent VTE and major bleeding. Secondary outcome was fatal bleeding. RESULTS: Recurrent VTEs occurred in 15.9/100 patient years (py) in patients without CKD (eGFR > 60 mL min(-1) ), 19.5/100 py in those with CKD stage 3A (eGFR 45-60 mL min(-1) ), 14.9/100 py in those with CKD 3B (eGFR 30-45 mL min(-1) ), and 6.8/100 py in patients with CKD 4-5 (eGFR < 30 mL min(-1) ). Major bleeding occurred in 11.4/100 py in patients without CKD, 18.5/100 py in those with CKD stage 3A, 16.0/100 py in those with CKD 3B, and 40.8/100 py in patients with CKD 4-5. Fatal bleeding occurred in 1.1/100 py, 3.4/100 py, 6.3/100 py and 15.7/100 py, respectively. These increased bleeding risks in CKD patients were mainly observed in those on LMWH treatment, not VKA. CONCLUSIONS: The risk of major bleeding was increased in CKD patients with VTE and cancer, and was most prominent in those treated with LMWH and an eGFR < 30 mL min(-1) . These results indicate that LMWH should be used with caution in this specific population.

Pupilometría por infrarrojos. Descripción y fundamentos de la técnica y su aplicación en la monitorización no invasiva del paciente neurocrítico / Infrared pupillometry. Basic principles and their application in the non-invasive monitoring of neurocritical patients

Introducción: La exploración de las pupilas constituye una parte fundamental de la exploración neurológica. El tamaño y la reactividad a la luz de ambas pupilas deben registrarse de forma individual y periódica, dado que una alteración en estos parámetros puede constituir el único signo detectable de deterioro neurológico en determinados pacientes. Sin embargo, existe una gran variabilidad intra-observadores e inter-observadores al analizar estos parámetros, debido a la influencia de una serie de factores tales como la variabilidad en la luz ambiental, la agudeza visual y experiencia del propio observador, intensidad del estímulo luminoso y el método utilizado para dirigir este estímulo. En los últimos años las cámaras digitales han incorporado dispositivos de infrarrojos que han permitido desarrollar equipos digitales portátiles y de fácil manejo, que permiten realizar estudios repetidos y no invasivos del tamaño y reactividad pupilar a la luz con un método objetivo, accesible y económico. Desarrollo: El objetivo de esta revisión es describir los fundamentos de la pupilometría por infrarrojos y discutir sus posibles aplicaciones en la monitorización del paciente neurocrítico. En esta revisión también se incluyen una serie de recomendaciones metodológicas a considerar en la exploración de las pupilas. Conclusiones: La posibilidad de evaluar los cambios en la reactividad pupilar de forma precoz, objetiva y quasi-continua aporta un nuevo método de monitorización no invasivo que podría mejorar el factor predictivo del deterioro neurológico y monitorizar el estado neurológico a la cabecera del paciente, evitando así exámenes innecesarios y permitiendo intervenciones terapéuticas precoces(AU)

Introduction: Pupil assessment is a fundamental part of the neurological examination. Size and reactivity to light of each pupil should be recorded periodically since changes in these parameters may represent the only detectable sign of neurological deterioration in some patients. However, there is great intraobserver and interobserver variability in pupil examination due to the influence of many factors, such as the difference in ambient lighting, the visual acuity and experience of the examiner, the intensity of the luminous stimulus, and the method used to direct this stimulus. In recent years, digital cameras have incorporated infrared devices allowing the development of user-friendly portable devices that permit repeated, non-invasive examinations of pupil size and its reactivity to light with an objective, accessible and inexpensive method. Development: The purpose of this review is to describe the fundamentals of infrared pupillometry and discuss potential applications in the monitoring of neurocritical patients. We also present some recommendations in the routine assessment of pupils in neurocritical patients. Conclusions: The possibility of evaluating the changes in pupil reactivity in an early, objective and almost continuous way provides a new non-invasive monitoring method. This method could improve the predictive factor of neurological deterioration and the bedside monitoring of the neurological state of the patient, avoiding unnecessary examinations and enabling early therapeutic intervention(AU)

Infrared pupillometry. Basic principles and their application in the non-invasive monitoring of neurocritical patients.

INTRODUCTION: Pupil assessment is a fundamental part of the neurological examination. Size and reactivity to light of each pupil should be recorded periodically since changes in these parameters may represent the only detectable sign of neurological deterioration in some patients. However, there is great intraobserver and interobserver variability in pupil examination due to the influence of many factors, such as the difference in ambient lighting, the visual acuity and experience of the examiner, the intensity of the luminous stimulus, and the method used to direct this stimulus. In recent years, digital cameras have incorporated infrared devices allowing the development of user-friendly portable devices that permit repeated, non-invasive examinations of pupil size and its reactivity to light with an objective, accessible and inexpensive method. DEVELOPMENT: The purpose of this review is to describe the fundamentals of infrared pupillometry and discuss potential applications in the monitoring of neurocritical patients. We also present some recommendations in the routine assessment of pupils in neurocritical patients. CONCLUSIONS: The possibility of evaluating the changes in pupil reactivity in an early, objective and almost continuous way provides a new non-invasive monitoring method. This method could improve the predictive factor of neurological deterioration and the bedside monitoring of the neurological state of the patient, avoiding unnecessary examinations and enabling early therapeutic intervention.

Fisiopatología de las tormentas eléctricas en el encéfalo del paciente con una lesión cerebral aguda. Resultados preliminares de un estudio piloto / Pathophysiology of electrical storms in the brain of patients with acute brain injury. Preliminary results of a pilot study

Los fenómenos de despolarización cortical propagada (CSD y CSD-like) son despolarizaciones celulares que se extienden en forma de onda y están implicados en la progresión de las lesiones en pacientes con ictus y traumatismo craneoencefálico (TCE). Son detectables en el registro de electrocorticografía (ECoG). Experimentalmente inducen hipoxia cerebral e incrementa la permeabilidad de la barrera hematoencefálica. Objetivos: Determinar la frecuencia y duración de estos episodios en pacientes con TCE o infarto maligno de la arteria cerebral media (IMACM) que requieran craniectomía. Material y métodos: 20 pacientes a los que se les colocó, en el córtex perilesional, una tira de seis electrodos. Análisis del número y la duración de los episodios de CSD registrados. Resultados: En cuatro, de los ocho registros de ECoG analizados, se identificaron episodios de CSD o CSD-like de duración y frecuencia variable. Conclusiones: Se detectan frecuentemente episodios de CSD y CSD-like en pacientes con IMACM y TCE (AU)

The phenomena of cortical spreading depolarization (CSD and CSD-like phenomena) are cellular depolarization waves involved in the progression of lesions in patients with stroke and traumatic brain injury (TBI). Which are detected by an electrocorticographic (ECoG) recording. Experimentally, CSD induces cerebral hypoxia and increases the permeability of the blood-brain barrier. Objectives: To determine the frequency and duration of CSD episodes in patients with TBI and malignant middle cerebral artery infarction (MMCAI) requiring craniectomy. Material and methods: 20 patients were included. A strip of 6 electrodes was placed in the perilesional cortex. Analysis of the number and duration of CSD episodes in the ECoG recording was performed. Results: In four, of the eight ECoG recordings that was fully analyzed, CSD or CSD-like phenomena were identified with a variable frequency and duration. Conclusions: Episodes of CSD and CSD-like phenomena are frequently detected in patients with MMCAI and TBI (AU)

Glucose control and outcome in patients with stable diabetes and previous coronary, cerebrovascular or peripheral artery disease. Findings from the FRENA Registry.

AIM: The aim of this study was to address the controversy over the influence of intensive glucose control on the risk for cardiovascular events in patients with Type 2 diabetes. METHODS: FRENA is an ongoing registry of stable outpatients with symptomatic coronary artery disease, cerebrovascular disease or peripheral artery disease. We compared the incidence of subsequent ischaemic events (myocardial infarction, stroke or critical limb ischaemia) in patients with Type 2 diabetes and mean HbA(1c) levels < 7.0% (< 53 mmol/mol) vs. those with HbA(1c) levels > 7.0% (> 53 mmol/mol). RESULTS: Of 974 patients with Type 2 diabetes, 480 (49%) had mean HbA(1c) levels < 7% (< 53 mmol/mol). Over a mean follow-up of 14 months, 126 patients (13%) had subsequent ischaemic events: myocardial infarction (43), stroke (29) and critical limb ischaemia (64). The incidence of subsequent ischaemic events was significantly lower in patients with mean HbA(1c) levels < 7.0% (< 53 mmol/mol) than in those with HbA(1c) levels > 7.0% (> 53 mmol/mol) (8.6 vs. 14 per 100 patient-years; rate ratio 0.6; 95% CI 0.4-0.9). These differences persisted after adjusting for potential confounders. However, this better outcome was only found in patients presenting with coronary artery disease (rate ratio 0.4; 95% CI 0.2-0.8), not in those with cerebrovascular disease (rate ratio 0.9; 95% CI 0.4-2.0) or peripheral artery disease (rate ratio 0.8; 95% CI 0.5-1.3). Patients with mean HbA(1c) levels < 7.0% (< 53 mmol/mol) also had a lower mortality (rate ratio 0.6; 95% CI 0.3-0.99). CONCLUSIONS: In secondary prevention, patients with diabetes and HbA(1c) levels < 7.0% (< 53 mmol/mol) had a lower incidence of subsequent ischaemic events and a lower mortality than those with HbA(1c) levels > 7.0% (> 53 mmol/mol). These differences appeared only in patients with coronary artery disease.

[Primary decompressive craniectomy in patients with aneurysmatic subarachnoid hemorrhage. Results of a pilot study in 11 cases]. / Craniectomía descompresiva primaria en la hemorragia subaracnoidea aneurismática. Resultados deun estudio piloto en 11 casos.

INTRODUCTION: Despite the scientific and technical advances of recent years, aneurysmal subarachnoid hemorrhage (aSAH) continues to present a high morbidity and mortality. This fact, together with the impressive results of the primary decompressive craniotomy (PDC) in the malignant infarction of the middle cerebral artery suggests a possible beneficial effect of decompressive technique in aSAH. We present our experience of a pilot study that PDC was used in patients with poorgrade aSAH with associated intracerebral hematoma. PATIENTS AND METHODS: Between March 1st, 2002 and 31st April, 2008, 342 patients with aneurysmatic subarachnoid hemorrhage (aSAH) were treated at our hospital. Of these, 64 had a poor neurological grade (scores of 4 or 5 of the World Federation of Neurosurgical Societies) at the time of admission. The present study examines 11 of those patients who underwent PDC, which is performed in the same clipping and / or evacuation of an associated hematoma. RESULTS: In three patients PDC was performed after endovascular aneurysm treatment because of the need to evacuate an associated hematoma. In the eight remaining patients, PDC was performed in the same clipping and evacuation of the associated hematoma. Outcome evaluation of these eleven patients was conducted 1 year after the operation assessed by the Glasgow Outcome Scale. Six patients survived, and four of them with good results. The PDC was effective in controlling intracranial pressure in all six surviving patients. However, two of these six patients had unfavorable outcomes. Of the five who didn't survive, one patient died from a delayed epidural-subgaleal hematoma as a complication of the decompressive technique, and the other four patients died because of refractory intracranial hypertension. CONCLUSIONS: Primary DC may be beneficial in selected subgroups of patients with poor-grade aSAH. However, there is a lack of definitive evidence to support a clear recommendation for its use.