39 research outputs found
Neonatal cerebrovascular autoregulation.
Cerebrovascular pressure autoregulation is the physiologic mechanism that holds cerebral blood flow (CBF) relatively constant across changes in cerebral perfusion pressure (CPP). Cerebral vasoreactivity refers to the vasoconstriction and vasodilation that occur during fluctuations in arterial blood pressure (ABP) to maintain autoregulation. These are vital protective mechanisms of the brain. Impairments in pressure autoregulation increase the risk of brain injury and persistent neurologic disability. Autoregulation may be impaired during various neonatal disease states including prematurity, hypoxic-ischemic encephalopathy (HIE), intraventricular hemorrhage, congenital cardiac disease, and infants requiring extracorporeal membrane oxygenation (ECMO). Because infants are exquisitely sensitive to changes in cerebral blood flow (CBF), both hypoperfusion and hyperperfusion can cause significant neurologic injury. We will review neonatal pressure autoregulation and autoregulation monitoring techniques with a focus on brain protection. Current clinical therapies have failed to fully prevent permanent brain injuries in neonates. Adjuvant treatments that support and optimize autoregulation may improve neurologic outcomes
Geotourism, iconic landforms and island-style speciation patterns in National Parks of East Africa:
Many of the national parks in East Africa are equally as famous for their iconic landforms as they are for their diversity and concentrations of fauna and flora. The newly formed Ngorongoro-Lengai Geopark in northern Tanzania is the first geopark to be established in the region, but there is remarkable potential for geotourism in the majority of the national parks. The most spectacular landforms have been shaped by the East African Rift System. Formation of the two major rifts in the region, the Albertine Rift (or western branch) and the Gregory Rift (or eastern branch), was accompanied, or in some cases preceded, by extensive alkaline volcanism. The rifting and volcanism are primarily Late Cenozoic phenomenon that dissected and overprinted the older regional plateaus. Rifting impacted the regional drainage and captured major rivers, including the Victoria Nile
Estudo da validade e confiabilidade intra e interobservador da versão modificada do teste de Schöber modificado em indivÃduos com lombalgia Study of validity and intra and inter-observer reliability of modified-modified Schöber test in subjects with low-back pain
Em pacientes com lombalgia, mensura-se a amplitude de movimento (ADM) da coluna lombar por meio da versão modificada do teste de Schöber modificado (MTSM), mas suas propriedades psicométricas não são comprovadas para uso clÃnico. Este estudo verificou a validade e confiabilidade intra e interobservador do MTSM em indivÃduos com lombalgia, comparando as medidas da ADM com as obtidas por meio de radiografia, método considerado padrão-ouro. Participaram 20 voluntários com lombalgia, de ambos os sexos, funcionários de um Hospital Universitário. O MTSM foi aplicado duas vezes por dois avaliadores. As medidas obtidas pelo teste e por radiografia foram comparadas usando o coeficiente de correlação de Pearson, obtendo-se r=0,14, ou seja, correlação fraca. O coeficiente de correlação intraclasse (CCI) dos MTSM intra-observador foi 0,96 (IC 95% 0,91;0,98) e interobservador 0,93 (IC 95% 0,84;0,97), indicando alta confiabilidade; o teste de Bland & Altman mostrou alta concordância intra e interobservador, com valores de -0,21 e -0,28, respectivamente. Embora tenha sido encontrada alta confiabilidade intra e interobservador na aplicação da versão modificada do teste de Schöber modificado, este apresentou baixa validade para medir a ADM da coluna lombar, quando comparado ao padrão-ouro.<br>In patients with low-back pain the lumbar spine range of motion (ROM) is often measured by the modified version of the modified Schöber test (MMST), but its psychometric properties have not been ascertained for clinical use. The purpose here was to verify intra and inter-observer validity and reliability of the MMST in subjects with low-back pain, and to compare obtained ROM measures to those obtained by radiography, taken as gold standard. The study involved 20 subjects with chronic low-back pain, of both sexes, employees at a university hospital. The MMST was applied twice by two examiners each. The Pearson correlation coefficient found when comparing measures obtained via MMST and radiography was r=0.14, showing a poor correlation between the tests. The intra-observer intraclass correlation coefficient (ICC) found was 0.96 (CI 95% 0.91;0.98), and the inter-observer ICC was 0.93 (IC 95% 0.84;0.97), showing high reliability; the Bland & Altman agreement test showed high agreement intra (-0.21) and inter-observer (-0.21). Although a high reliability both intra and inter-observer was found for the modified-modified Schöber test, the latter showed low validity in assessing lumbar spine range of motion, when compared to the gold standard