Factores predominantes de encefalopatía neonatal: hipoxia e isquemia, un problema global / Predominant factors of neonatal encephalopathy: hypoxic and ischemia, a global problem

Si una dificultad sobreviene durante el nacimiento de un niño, por una anomalía materna o fetal, aguda o crónica, la asfixia del cerebro fetal constituye un riesgo mayor, porque ella podría dar como resultado la destrucción de las neuronas y la posibilidad de evolucionar hacia una encefalopatía hipóxico isquémica con secuelas a largo plazo. En esta revisión se resaltan los aspectos científicos más recientes pero a la vez se ofrece un margen de conocimiento imprescindible en cuanto a la patofisiología, diagnóstico y tratamiento, así como también se ofrece una perspectiva sobre el futuro de la atención clínica de la encefalopatía hipóxico isquémica.

If a difficulty arises during birth, due to a maternal or fetal anomaly, acute or chronic, asphyxia of the fetal brain constitutes a greater risk, because it could result in the destruction of neurons and the possibility of evolving towards a Ischemic Hypoxic Encephalopathy with long -term sequelae. This review highlights the most recent scientific aspects but at the same time it offers an essential margin of knowledge regarding pathophysiology, diagnosis and treatment, as well as offering a perspective on the future of clinical care of ischemic hypoxic encephalopathy.

Effect of hyperbaric oxygenation on mitochondrial function of neuronal cells in the cortex of neonatal rats after hypoxic-ischemic brain damage

The timing and mechanisms of protection by hyperbaric oxygenation (HBO) in hypoxic-ischemic brain damage (HIBD) have only been partially elucidated. We monitored the effect of HBO on the mitochondrial function of neuronal cells in the cerebral cortex of neonatal rats after HIBD. Neonatal Sprague-Dawley rats (total of 360 of both genders) were randomly divided into normal control, HIBD, and HIBD+HBO groups. The HBO treatment began immediately after hypoxia-ischemia (HI) and continued once a day for 7 consecutive days. Animals were euthanized 0, 2, 4, 6, and 12 h post-HI to monitor the changes in mitochondrial membrane potential (ΔΨm) occurring soon after a single dose of HBO treatment, as well as 2, 3, 4, 5, 6, and 7 days post-HI to study ΔΨm changes after a series of HBO treatments. Fluctuations in ΔΨm were observed in the ipsilateral cortex in both HIBD and HIBD+HBO groups. Within 2 to 12 h after HI insult, the ΔΨm of the HIBD and HIBD+HBO groups recovered to some extent. A secondary drop in ΔΨm was observed in both groups during the 1-4 days post-HI period, but was more severe in the HIBD+HBO group. There was a secondary recovery of ΔΨm observed in the HIBD+HBO group, but not in the HIBD group, during the 5-7 days period after HI insult. HBO therapy may not lead to improvement of neural cell mitochondrial function in the cerebral cortex in the early stage post-HI, but may improve it in the sub-acute stage post-HI.

Hipotermia terapêutica para recém-nascidos com encefalopatia hipóxico isquêmica / Hypothermia therapy for newborns with hypoxic ischemic encephalopathy

Resumo Objetivo: A hipotermia terapêutica reduz a lesão cerebral e melhora o desfecho neurológico de recém-nascidos após insulto hipóxico isquêmico. Indicada para recém-nascidos a termo ou próximo do termo com evidência de asfixia perinatal e encefalopatia hipóxico isquêmica (EHI). Fontes dos dados: Foi feita uma procura no PubMed por publicações sobre hipotermia terapêutica em recém-nascidos com asfixia perinatal e selecionadas aquelas julgadas mais relevantes pelos autores. Síntese dos dados: Há duas técnicas de resfriamento corpóreo: hipotermia seletiva da cabeça e hipotermia corpórea total. A temperatura de resfriamento deve ser 34,5 ºC para seletiva de cabeça e 33,5 ºC para corpórea total; temperaturas inferiores a 32 ºC são menos neuroprotetoras e abaixo de 30 ºC há efeitos adversos sistêmicos graves. Indica-se o início da hipotermia terapêutica até seis horas após o nascimento, pois estudos evidenciaram que essa é a janela terapêutica da agressão hipóxico e isquêmica. A hipotermia deve ser mantida por 72 horas com rigorosa monitoração da temperatura corporal do recém-nascido. A hipotermia tem sido efetiva em reduzir sequelas neurológicas, principalmente em recém-nascidos de termo ou próximo do termo com encefalopatia hipóxico isquêmica moderada e em melhorar o prognóstico em longo prazo dos recém-nascidos com EHI. Conclusão: A hipotermia terapêutica é uma técnica neuroprotetora indicada para recém-nascidos com asfixia perinatal.

Abstract Objective: Therapeutic hypothermia reduces cerebral injury and improves the neurological outcome secondary to hypoxic ischemic encephalopathy in newborns. It has been indicated for asphyxiated full-term or near-term newborn infants with clinical signs of hypoxic-ischemic encephalopathy (HIE). Sources: A search was performed for articles on therapeutic hypothermia in newborns with perinatal asphyxia in PubMed; the authors chose those considered most significant. Summary of the findings: There are two therapeutic hypothermia methods: selective head cooling and total body cooling. The target body temperature is 34.5 ºC for selective head cooling and 33.5 ºC for total body cooling. Temperatures lower than 32 ºC are less neuroprotective, and temperatures below 30 ºC are very dangerous, with severe complications. Therapeutic hypothermia must start within the first 6 hours after birth, as studies have shown that this represents the therapeutic window for the hypoxic-ischemic event. Therapy must be maintained for 72 hours, with very strict control of the newborn's body temperature. It has been shown that therapeutic hypothermia is effective in reducing neurologic impairment, especially in full-term or near-term newborns with moderate HIE. Conclusion: Therapeutic hypothermia is a neuroprotective technique indicated for newborn infants with perinatal asphyxia and HIE.

Clinical utility of early amplitude integrated EEG in monitoring term newborns at risk of neurological injury / Utilidade clínica de um monitoramento por EEG de amplitude integrada precoce em recém-nascidos a termo com risco de lesão neurológica

OBJECTIVE: to test the clinical utility of an early amplitude-integrated electroencephalography (aEEG) to predict short-term neurological outcome in term newborns at risk of neurology injury. METHODS: this was a prospective, descriptive study. The inclusion criteria were neonatal encephalopathy, neurologic disturbances, and severe respiratory distress syndrome. Sensitivity, specificity, positive and negative predictive values, and likelihood ratio (LR) were calculated. Clinical and demographic data were analyzed. Neurological outcome was defined as the sum of clinical, electroimaging, and neuroimaging findings. RESULTS: ten of the 21 monitored infants (48%) presented altered short-term neurologic outcome. The aEEG had 90% sensitivity, 82% specificity, 82% positive predictive value, and 90% negative predictive value. The positive LR was 4.95, and the negative LR was 0.12. In three of 12 (25%) encephalopathic infants, the aEEG allowed for a better definition of the severity of their condition. Seizures were detected in eight infants (38%), all subclinical at baseline, and none had a normal aEEG background pattern. The status of three infants (43%) evolved and required two or more drugs for treatment. CONCLUSIONS: in infants with encephalopathy or other severe illness, aEEG disturbances occur frequently. aEEG provided a better classification of the severity of encephalopathy, detected early subclinical seizures, and allowed for monitoring of the response to treatment. aEEG was a useful tool at the neonatal intensive care unit for predicting poor short-term neurological outcomes for all sick newborn. .

OBJETIVO: testar a utilidade clínica do aEEG precoce em recém-nascidos a termo com risco delesão neurológica, para prever resultados neurológicos de curto prazo. MÉTODOS: estudo prospectivo e descritivo. Os critérios de inclusão foram encefalopatia neonatal, distúrbios neurológicos e bebês com SARA grave. Sensibilidade, especificidade, valor preditivo positivo e negativo e razão de verossimilhança foram calculados. Dados clínicos edemográficos foram analisados. O resultado neurológico foi definido como a soma de conclusões clínicas, de eletro e de neuroimagem. RESULTADOS: dentre os 21 neonatos monitorados, dez (48%) apresentaram resultado neurológico de curto prazo alterado. O aEEG apresentou sensibilidade de 90%, especificidade de 82%, valor preditivo positivo de 82% e valor preditivo negativo de 90%. A VR positiva foi de 4,95, e a RV negativa de 0,12. Em três dos 12 (25%) neonatos com encefalopatia foi possível definir melhora gravidade de sua condição pelo aEEG. Foram detectadas convulsões em oito neonatos (38%), todas subclínicas no início do estudo, e nenhum apresentou um padrão histórico normal no aEEG. O estado de três neonatos (43%) evoluiu e exigiu dois ou mais medicamentos para tratamento. CONCLUSÕES: em neonatos com encefalopatia ou outra doença grave, os distúrbios no aEEGocorrem com mais frequência. O aEEG forneceu uma classificação melhor da gravidade da encefalopatia, detectou convulsões subclínicas precoces e permitiu que fosse feito o monitoramento da resposta ao tratamento. O aEEG é uma ferramenta útil para prever resultados neurológicos de curto prazo em todos os bebês doentes na UTIN. .

Hipoxia perinatal y su impacto en el neurodesarrollo / Perinatal hypoxia and its impact on neurodevelopment

Durante el periodo perinatal el cerebro puede quedar privado de oxígeno por dos mecanismos importantes: la hipoxemia y la isquemia. El primero consiste en una disminución de la concentración de oxígeno en sangre y el segundo en la cantidad de sangre que riega al cerebro. Clínicamente se le conoce como encefalopatía hipoxia-isquémica al síndrome caracterizado por la suspensión o grave disminución del intercambio gaseoso a nivel de la placenta o de los pulmones, que resulta en hipoxemia, hipercapnia e hipoxia tisular con acidosis metabólica. Los cambios metabólicos resultantes provocan a corto plazo daño necrótico y a largo plazo daño apoptótico. Las principales lesiones neurológicas que se presentan son la necrosis neuronal selectiva, la lesión cerebral parasagital y la leucomalacia periventricular, provocando secuelas como la parálisis cerebral, epilepsia, problemas en el habla y el lenguaje, auditivos y neuropsicológicos, siendo los procesos, atencionales, mnémicos, y visuoespaciales los más representativos en este rubro. En México se reporta una incidencia de 14.6 por cada 1,000 recién nacidos vivos, con una letalidad del 8.5 por ciento y un índice de secuelas de 3.6 por ciento. A pesar de la gran cantidad de estos estudios sobre secuelas de la hipoxia perinatal aún son pocos los programas a nivel institucional enfocados en el diagnóstico y tratamiento temprano.

During the perinatal period the brain can be deprived of oxygen by two major mechanisms, hypoxemia and ischemia. The first consists in a decrease in blood oxygen concentration and the second in the amount of blood that irrigates the brain. Clinically, it is known as hypoxic-ischemic encephalopathy; a syndrome characterized by severe suspension or decreased gas exchange in the placenta or lungs, resulting in hypoxemia, hypercapnia and tissue hypoxia with metabolic acidosis. A metabolic short-term change causes necrotic damage and long-term change causes apoptotic damage. The main neurological injuries that occur are selective neuronal necrosis, parasagittal brain injury and periventricular leukomalacia, causing sequelae such as cerebral palsy, epilepsy, speech and language disorders, lost hearing and neuropsychological deficits, especially in attentional, mnemonic, and visuospatial proceses. In our country, an incidence of 14.6 per 1,000 live births, with a mortality rate of 8.5 percent and 3.6 sequels index percent are reported. Despite the large number of studies about consequences of perinatal hipoxia are still few institutional level programs focused on early diagnosis and treatment.

Learning and survival memory undergoing a permanent bilateral carotid ligation in rats

PURPOSE: To evaluate the effect of cerebral hypoxia-ischemia on memory and learning survival of rats submitted to permanent bilateral carotid ligation (PBCL). METHODS: Twenty-four survivors of PBCL were evaluated after 30 days with regard to memory and learning using a water survival maze. Twenty-three healthy rats were used as control group. The results were expressed by their means and standard error of the mean (SEM). p<0.05 was used for rejecting the null hypothesis. The study was approved by the Ethics Committee for animal investigation. RESULTS: The mortality rate for the surgery was 44.4%. The latency time to find the survival platform was higher in rats that underwent PBCL (Normal: 10.24 ± 1.85s - Study: 25.30 ± 4.69s - Mann - Whitney p=0.0388). Additionally, the type of swimming and the spatial stability of the studied rats on the survival platform were compromised in these animals. CONCLUSION: The permanent bilateral carotid ligation induces change in the learning and survival memory.

Encefalopatias: etiologia, fisiopatologia e manuseio clínico de algumas das principais formas de apresentação da doença / Encephalopathies: etiology, pathophysiology, and clinical management of some major forms of disease presentation

JUSTIFICATIVA E OBJETIVOS: As encefalopatias compõem um grupo heterogêneo de etiologias, onde a pronta e correta atuação médica direcionada à causa da doença, pode modificar o prognóstico do paciente. O objetivo deste estudo foi rever os aspectos fisiopatológicos das diferentes encefalopatias bem como seus principais fatores desencadeantes e manuseio clínico.CONTEÚDO: Foram selecionadas as mais frequentes encefalopatias observadas na prática clínica e discutir sua fisiopatologia, bem como sua abordagem terapêutica, destacando: encefalopatia hipertensiva, hipóxico-isquêmica, metabólica, Wernicke-Korsakoff, traumática e tóxica.CONCLUSÃO: Trata-se de uma complexa condição clínica que exige rápida identificação e preciso manuseio clínico com o intuito de reduzir sua elevada taxa de morbimortalidade. O atraso no reconhecimento dessa condição clínica poderá ser extremamente prejudicial ao paciente que estará sofrendo lesão cerebral muitas vezes irreversível.

BACKGROUND AND OBJECTIVES: Encephalopathies comprise a heterogeneous group of clinical conditions, in which the prompt and adequate medical intervention can modify patient prognosis. This paper aims to discuss the pathophysiological aspects of different encephalopathies, their etiology, and clinical management.CONTENTS: We selected the main encephalopathies observed in clinical practice, such as hypertensive, hypoxic-ischemic, metabolic, Wernicke-Korsakoff, traumatic, and toxic encephalopathies, and to discuss their therapeutic approaches.CONCLUSION: This is a complex clinical condition that requires rapid identification and accurate clinical management with the aim of reducing its high morbidity and mortality rates. Delay in recognizing this condition can be extremely harmful to the patient who is suffering from often irreversible brain injury.

Decreased levels of pNR1 S897 protein in the cortex of neonatal Sprague Dawley rats with hypoxic-ischemic or NMDA-induced brain damage

Our objective was to investigate the protein level of phosphorylated N-methyl-D-aspartate (NMDA) receptor-1 at serine 897 (pNR1 S897) in both NMDA-induced brain damage and hypoxic-ischemic brain damage (HIBD), and to obtain further evidence that HIBD in the cortex is related to NMDA toxicity due to a change of the pNR1 S897 protein level. At postnatal day 7, male and female Sprague Dawley rats (13.12 ± 0.34 g) were randomly divided into normal control, phosphate-buffered saline (PBS) cerebral microinjection, HIBD, and NMDA cerebral microinjection groups. Immunofluorescence and Western blot (N = 10 rats per group) were used to examine the protein level of pNR1 S897. Immunofluorescence showed that control and PBS groups exhibited significant neuronal cytoplasmic staining for pNR1 S897 in the cortex. Both HIBD and NMDA-induced brain damage markedly decreased pNR1 S897 staining in the ipsilateral cortex, but not in the contralateral cortex. Western blot analysis showed that at 2 and 24 h after HIBD, the protein level of pNR1 S897 was not affected in the contralateral cortex (P > 0.05), whereas it was reduced in the ipsilateral cortex (P < 0.05). At 2 h after NMDA injection, the protein level of pNR1 S897 in the contralateral cortex was also not affected (P > 0.05). The levels in the ipsilateral cortex were decreased, but the change was not significant (P > 0.05). The similar reduction in the protein level of pNR1 S897 following both HIBD and NMDA-induced brain damage suggests that HIBD is to some extent related to NMDA toxicity possibly through NR1 phosphorylation of serine 897.

Neuroprotección mediante hipotermia moderada en recién nacidos con encefalopatía hipóxico-isquémica / Neuroprotection by mild hypothermia in newborn with hypoxic-ischemic encephalopathy

En la mayoría de los países desarrollados el tratamiento con la hipotermia se ha convertido en un pilar fundamental para la neuroprotección del recién nacido con encefalopatía hipóxico-isquémica (EHI). En la unidad de cuidados intensivos neonatales de la universidad de Duke, la hipotermia moderada se aplica desde el 2005. El tratamiento con hipotermia es muy limitado en otros países porque en adición a un equipamiento especializado, requiere de manejo detallado de las disfunciones multiorgánicas, documentación meticulosa de la información clínica con cuidados y control del paciente en forma protocolizada. Como punto de partida, y para facilitar la introducción de la hipotermia en las unidades de cuidados intensivos neonatales en Uruguay, se presenta la evolución de cinco pacientes internados en la unidad de cuidados intensivos del centro hospitalario de Duke (Carolina del Norte, EE.UU.), evaluando la respuesta al tratamiento con hipotermia moderada y su evolución clínica

The modified 2VO ischemia protocol causes cognitive impairment similar to that induced by the standard method, but with a better survival rate

Permanent bilateral occlusion of the common carotid arteries (2VO) in the rat has been established as a valid experimental model to investigate the effects of chronic cerebral hypoperfusion on cognitive function and neurodegenerative processes. Our aim was to compare the cognitive and morphological outcomes following the standard 2VO procedure, in which there is concomitant artery ligation, with those of a modified protocol, with a 1-week interval between artery occlusions to avoid an abrupt reduction of cerebral blood flow, as assessed by animal performance in the water maze and damage extension to the hippocampus and striatum. Male Wistar rats (N = 47) aged 3 months were subjected to chronic hypoperfusion by permanent bilateral ligation of the common carotid arteries using either the standard or the modified protocol, with the right carotid being the first to be occluded. Three months after the surgical procedure, rat performance in the water maze was assessed to investigate long-term effects on spatial learning and memory and their brains were processed in order to estimate hippocampal volume and striatal area. Both groups of hypoperfused rats showed deficits in reference (F(8,172) = 7.0951, P < 0.00001) and working spatial memory [2nd (F(2,44) = 7.6884, P < 0.001), 3rd (F(2,44) = 21.481, P < 0.00001) and 4th trials (F(2,44) = 28.620, P < 0.0001)]; however, no evidence of tissue atrophy was found in the brain structures studied. Despite similar behavioral and morphological outcomes, the rats submitted to the modified protocol showed a significant increase in survival rate, during the 3 months of the experiment (P < 0.02).

Effect of an isolated mild to moderate ischemic brain injury in the gastric emptying of liquids in rats / Efeito de lesão cerebral hipóxico-isquêmica isolada no esvaziamento gástrico de uma solução salina em ratos

PURPOSE: To evaluate the effect of hypoxic-ischemic brain injury over the gastric emptying of liquids in rats. METHODS: Fifty-two Wistar rats aged six weeks and weighing between 100g and 150g were divided in three groups. A Control group (C), a Sham group (S) undergoing sham procedure, and a Hypoxic-ischemic group (HI) consisting of 18 animals undergoing surgical ligature of the left carotid artery and exposure to hypoxic environment for three hours. Half of the animals were studied in the third day post-HI procedure (Early) and nine in the 14th day post-HI procedure (Late). Gastric emptying was evaluated by an infusion technique using fenolsulftalein as a marker. RESULTS: After the HI procedure, all animals displayed left eyelid ptosis, and six animals showed minor sideway gait. Histological examination confirmed de brain injury in all animals from the HI group. There was no statistical significant difference among the mean gastric retention values of the three groups neither in the Early nor in the Late evaluation. CONCLUSION: Isolated HI brain injury was not associated with delayed gastric emptying.

OBJETIVO: Avaliar o efeito de lesão cerebral hipoxico-isquêmica sobre esvaziamento gástrico (EG) de líquidos em ratos. MÉTODOS: Cinqüenta e dois ratos Wistar com seis semanas de idade e pesando entre 100g e 150g foram divididos em três grupos. Um grupo Controle (C), um grupo Sham (S) de 18 animais submetidos a manipulação da artéria carótida esquerda sem ligadura e um grupo Hipoxico-isquêmico (HI) que consistiu de 18 animais submetidos a ligadura cirúrgica da artéria carótida esquerda e exposição a ambiente hipóxico por três horas. Metade dos animais foi estudada no terceiro dia pós-procedimento (Precoce) e a outra metade no 14º dia pós-procedimento (Tardio). O EG de uma solução salina foi avaliado por uma técnica de infusão usando a fenolsulftaleína como um marcador. RESULTADOS: Após o procedimento de HI, todos os animais apresentaram ptose palpebral à esquerda e seis animais mostraram leve desvio da marcha. O exame histológico do cérebro confirmou lesão cerebral em todos os animais do grupo HI. Não foi observada diferença estatística significativa entre os valores médios da retenção gástrica dos três grupos nem nas observações Precoces nem nas Tardias. CONCLUSÃO: A lesão cerebral difusa isolada provocada por um episódio HI não esta associada com retarde de esvaziamento gástrico de uma refeição líquida não calórica.

Relação entre índice de resistência obtido pela ultra-sonografia Doppler transfortanela e o neurodesenvolvimento até o primeiro ano de vida em recém-nascidos a termo com encefalopatia hipóxico-isquêmica leve e moderada / Relation between the resistance index obtained by the transfontanellar Doppler ultrasonography and the neurological development until the first year of life in term infants with mild or moderate hypoxic-ischaemic encephalopathy

OBJETIVO: Avaliar a relação do índice de resistência (IR) obtido pela ultra-sonografia Doppler transfontanela com o neurodesenvolvimento até um ano de idade, em recém-nascidos (RN) a termo com encefalopatia hipóxica-isquêmica (EHI) leve a moderada, secundária à asfixia intra-parto. MÉTODO: Estudo prospectivo em 20 RN com EHI leve a moderada, IR elevado no primeiro exame de Doppler, e sem doenças associadas ou anormalidades morfológicas cerebrais. Foram realizados exames seriados bimensais de Doppler transfontanela a partir do sétimo dia de vida, e avaliações clínicas mensais do neurodesenvolvimento no primeiro ano de vida. RESULTADOS: Houve normalização progressiva dos valores de IR até o último exame realizado. Cinco pacientes apresentaram normalização clínico-neurológica no período neonatal, após o primeiro exame de Doppler. Quinze lactentes apresentaram alterações neurológicas com resolução a partir do segundo trimestre de vida. CONCLUSÃO: Houve relação entre os períodos em que ocorreu a normalização dos valores de IR e a melhora clínica-neurológica.

OBJECTIVE: To evaluate the relation between the resistance index (RI) obtained by transfontanellar Doppler ultrasonography, and the neurodevelopment until one year of life, at term newborns with mild or moderate hypoxic-ischaemic encephalopathy due to intrapartum asphyxia. METHOD: 20 term newborns, with mild or moderate hypoxic-ischemic encephalopathy, high values of resistance index in the first exam, and without cerebral morfologic abnormalities or other diseases. They were submitted to serial bimonthly transfontanellar Doppler ultrasonography, from the seventh day of life on, and monthly clinical neurodevelopment assessment until one year of life. RESULTS: There was a progressive normalization of RI values until the last examination. In five cases there were clinical neurologic normalization in the neonatal period after the first Doppler exam. Fifteen infants presented neurologic abnormalities, with normalization after the second trimester of life. CONCLUSION: There was a relation between the normal RI values with the normalization of the clinical assessment.

The value of brainstem evoked potential in clinical decision of a patient with hypoxic-ischemic encephalopathy

Establishing a prognosis for hypoxic-ischemic encephalopathy during the neonatal period is extremely difficult, as the neuroplasticity of the developing brain makes it almost impossible to measure the affected area. This case report describes a newborn with severe perinatal asphyxia and neonatal neurological syndrome including absent suck reflex. Normal brainstem auditory evoked potential led the diagnosis towards a transitory dysfunction of deglutition, and the subject received daily stimulation in the hospital environment. Suck developed satisfactorily by day of life 30 and the patient was released without having to be tube fed. Neurophysiologic tests can be of value in the clinical decisions and analysis of functional prognosis of patients with hypoxic-ischemic encephalopathy.

Estabelecer o prognóstico da encefalopatia hipóxico-isquêmica durante o período neonatal é extremamente difícil, devido à neuroplasticidade do cérebro em desenvolvimento que impede a medida exata das áreas afetadas. Este relato descreve um recém-nascido a termo com grave asfixia perinatal e síndrome neurológica pós-natal, incluindo ausência do reflexo de sucção. O potencial evocado auditivo do tronco cerebral foi normal, sugerindo o diagnóstico de disfunção transitória da deglutição. Após estimulação diária no hospital a sucção foi obtida satisfatoriamente, e o paciente recebeu alta sem necessidade de alimentação enteral. Os testes neurofisiológicos podem ser de grande valor em decisões clínicas e análise funcional prognóstica de pacientes com encefalopatia hipóxico-isquêmica.

La encefalopatía hipóxico isquémica: una aproximación medicolegal / Ischemic hypoxic encephalopathy: A medicolegal approach

La encefalopatía hipóxico isquémica es el daño que resulta en el sistema nervioso central por el suministro inadecuado de oxígeno y sangre. Su fisiopatología es diferente en el periodo neonatal y en las otras etapas de la vida. Se hace una revisión de la fisiopatología y de las aplicaciones medicolegales...

Coma anóxico-isquémico en 46 pacientes: Evolución a treinta días y su relación con los reflejos de tronco / The absence of brainstem reflexes does not predict short term mortality in anoxic ischemic coma

Background: Anoxic-ischemic coma has a poor outcome with a high rate of mortality and morbidity. Therefore, clinical predictors of prognosis are needed for therapeutic decision-making. Patients and methods: Prospective analysis of 46 patients, 31 male, age range 19-85 years, with anoxic-ischemic coma following cardiac arrest. All the patients included in our study remained comatose with a Glasgow Coma Scale (GCS) score of six or less points, after their stabilization in the Intensive Care Unit. They were evaluated clinically using the pupillary light reflex, corneal reflex and vestibulo-ocular reflex testing, induced by caloric stimulation with cold water. Survival was evaluated using life tables. All patients were followed until the thirtieth day after the anoxic-ischemic event. Results: Thirty five patients (76%) died within the next twenty-nine days, 8 patients (18%) reached the vegetative state, 2 patients (4%) achieved a recovery with disability, and only 1 patient (2%) was discharged without sequelae. One day, five and 30 days survival rates were 89, 53 and 29%, respectively. The abolition of all brainstem reflexes was not a predictor of mortality. Conclusion: Thirty day survival in this group of patients was 29% and the absence of brainstem reflexes was not a predictor of mortality.