Immunohistochemical identification of the endocrine cells in the pancreatic islets of the camel, horse and cattle

This study considers the distribution of various endocrine cells in islets of Langerhans in the pancreas of several species of domestic animal, including the dromedary camel (Camelus dromedarius) using immunohistochemistry, and relates our observations with reference to the well-documented general histology of the mammalian pancreas. The pancreatic islets were observed as compact areas of pale cells surrounded by darker presumably exocrine tissue. The most distinct delineation of the islets from the surrounding acini was in the horse and the least was in cattle. Insulin-immunoreactive cells (β-cells) were most abundant followed by glucagon- (α-), somatostatin- (∆-), and pancreatic polypeptide-immunoreactive (F- or PP-) cells in decreasing order, in all species except cattle where PP-cells were second to β-cells in their distribution. The most prominent special pattern was observed in the distribution of α- and β- cells in the pancreatic islet of the horse where α-cells were located in the center of the islet surrounded by β-cells. In the camel, β-cells were distributed throughout the islet in the center and the periphery. Alpha cells were mostly observed as clumps in the periphery area. Clumps of small number of ∆-cells and a few PP cells were found throughout the islet. In cattle, β-cells were distributed throughout the islets. Other cells occupied a more peripheral location. The physical differences in distribution of endocrine cells might result in differences in the need and interaction of hormones to each other in different species

No disponible

Monitorización de la sedación / Monitoring of sedation

Una vez asegurada la analgesia, la sedación adquiere especial relevancia en el tratamiento integral del paciente crítico ventilado. Los sedantes se deben ajustar a las necesidades individuales del paciente, administrando la mínima dosis necesaria para conseguir el objetivo. Este objetivo debe ser claramente identificado, definido al inicio de la terapéutica y revisado de forma regular, idealmente al menos una vez por turno. La estrategia de sedación debe prever las distintas necesidades a lo largo del día, enmarcándose dentro del contexto de la denominada sedación dinámica. La profundidad de sedación necesaria dependerá de las características psicológicas del paciente, de la naturaleza y gravedad de su situación clínica, de la evolución prevista y de su tolerancia a las técnicas de soporte usadas para el tratamiento. La monitorización de la sedación permite identificar y corregir situaciones de infra o sobresedación que pueden influir negativamente en la evolución de los pacientes críticos. El concepto de sobresedación deberá aplicarse a toda aquella situación en la que al paciente se le administre más sedación de la que realmente necesite. La Richmond agitation sedation scale, por su conexión con el Confusion Assessment Method para la Unidad de Cuidados Intensivos (CAM-ICU), es la recomendada por el Grupo de Trabajo para la monitorización de los pacientes con necesidades de sedación no profunda y la monitorización con el análisis biespectral (BIS®) en los que necesitan sedación profunda. En este caso, valores inferiores de 40 en el BIS® no aportan beneficios, salvo en aquellos pacientes en los que se requiera disminuir al máximo el metabolismo neuronal. La monitorización con BIS® es muy recomendable en los pacientes tratados con bloqueo neuromuscular para impedir los fenómenos de recall (AU)

Once analgesia is assured, sedation has special relevance in the critically ill ventilated patient’s global treatment. Sedatives should be adjusted to individual needs, by administering minimal effective doses to achieve the aim. This aim must be clearly identified, defined at the beginning of the treatment and revised on a regular basis, ideally at least once per shift. Sedation strategies should foresee the different needs throughout the day within dynamic sedation concept framework. Required sedation depth de- pends on the patient’s psychological characteristics, foreseen evolution and patient tolerance to the support techniques used in treatment. Sedation monitoring permits identification and correction of under- or over-sedation, either of which could negatively influence critically ill patient evolution. The over-sedation concept must be applied to all situations where patients receive more sedation than required. This Spanish Society of Critical Care Medicine’s Analgesia and Sedation Work Group recommends the Richmond Agitation Sedation Scale, due to its interrelationship with the Confusion Assessment Method Scale (CAM-ICU), for sedation monitoring in patients under light sedation while it recommends bispectral index sedation monitoring in patients under deep sedation. In the latter case, maintaining values under 40 on the bispectral index doesn’t produce any benefits except in patients who re- quire a maximum decrease in neuronal metabolism. To avoid recall phenomena, bispectral monitoring is highly advisable in patients treated with neuromuscular blockers (AU)