20 research outputs found
Cisatracurio
El cisatracurio es uno de los 10 isómeros que forman la mezcla racémica de atracurio (el 51W89 o 1R-cis, 1’Rcis atracurio). Se caracteriza por ser 3 veces más potente que el atracurio y por su estabilidad hemodinámica debido a la escasa liberación de histamina.
Se hidroliza básicamente por la vía de Hofmann (77%) y en menor proporción se metaboliza de modo órgano-dependiente (fundamentalmente por el riñón [16%]). Debido a esto, apenas precisa modificaciones de la dosificación en caso de enfermedad hepática, renal o cardiovascular, o en los pacientes ancianos.
La dosis eficaz 95 se ha calculado en 0,05 mg•kg-1 (0,04 mg•kg-1 en los niños), aunque clínicamente se utiliza de 2-4 veces esta dosis para reducir el tiempo necesario para la intubación traqueal debido a su lento inicio del bloqueo, especialmente si se compara con el rocuronio. Al incrementar la dosis se prolonga el período de bloqueo profundo (sin respuesta a la neuroestimulación), pero al iniciarse la recuperación cursa de forma dosis-dependiente, con índices de recuperación similares.
La utilización del cisatracurio en cuidados intensivos ha resultado ser útil por su estabilidad hemodinámica, equiparable a los derivados esteroides, pero con recuperación más rápida del bloqueo al suspender su administración, y por su metabolismo predominante mediante la vía de Hofmann, con menor formación de laudanosina que el atracurio.
El cisatracurio se perfila corno un miorrelajante no despolarizante de elección en procedimientos quirúrgicos de duración media-larga, en los pacientes hemodinámicamente inestables o con enfermedad renal o hepática y en el bloqueo neuromuscular en cuidados intensivos
Reducción de los requerimientos de hemoderivados en el trasplante hepático con aprotinina
Prophylactic use of aprotinin during surgery has a beneficial effect on hemostatic mechanisms, reducing the need for blood products. A reduction in fibrinolysis seems to contribute to this effect
Depresión del sistema mononuclear-fagocítico provocada por altas dosis de morfínico
We evaluated in human monocytes the effect of high doses of alfentanyl on the expression of vimentin filaments, the phagocytic activity and the membrane display of HLA-DR molecules in the subjects undergoing surgery. The study was performed on 30 patients, ASAI-II. The patients received 100 mcg/kg i.v. of Alfentanil and the maintenance of anaesthesia was made with Alfentanil (2-3 mcg/kg/min.). The patients were randomized in two groups. The patients were ventilated with N2O:O2 (1:1) (Group I) or air: O2 (1:1) (Group II). After surgery, all patients of the Group II received Naloxone (0.2-0.4 mg). Central venous blood samples were obtained before induction, one and two hours after induction of anaesthesia and at the end of surgery. Separation of monocytes was performed according to Boyum technique. CD35 and HLA-DR molecules and vimentin filaments were studied by indirect immunofluorescence method using monoclonal antibodies. Percentage of positive cells were read with a cytofluorometer. The phagocytic function of monocytes was determined by ingestion of latex particles. Cortisol and ACTH plasma levels were determined by RIA. High doses of Alfentanyl depress phagocytic function and membrane display of CD35 and HLA-DR molecules in monocyte and induce marked changes in the organization of vimentin filaments in these cells in patients undergoing surgery. This monocytic depression was more marked in the patients ventilated with N2O. In our results there was uninhibition of ACTH and cortisol plasma levels responses to surgical stress by Alfentanil administration. Since the effects of Alfentanil were reversed by Naloxone, an opioid receptor mechanism seems to mediate these event
Validación de un paratrike como plataforma para la captación de imágenes de alta resolución en formaciones de Abies pinsapo Boiss.
In this MSc Project, a paratrike was enabled to capture high-resolution images of Abies pinsapo Boiss formations. The formation in this study is located in Sierra de Las Nieves Natural Park, in the municipality of Parauta (Málaga). Three sensors; RGB, multispectral and thermal, were simultaneously installed in the paratrike. A coupling was created for the purpose of keeping the sensors well fixed to the vehicle during the execution of theflight. The field sampling was stratified and directed only to individuals of Spanish firs in order to produce adefoliation and mortality cartography, associated with the fungus H. abietinum that causes root rot and the barkbeetle C. numidicus, which causes death of the highest parts by ringing the shaft. Four types of damage were identified in this fieldwork; class 0, healthy, class 1, affected by C. numidicus, class 2, possibly affected by H.abietinum and class 3, dead individuals. The cartographic products obtained by the Sequoia Parrot sensor were of high quality. The same can not be said for the other two built in sensors. Due to the difficulties encountered during the flight (thermal turbulence), the predetermined flight plan was not carried out exhaustively and therefore the overlap between images was insufficient for the Gobi 640 GiGe thermal sensor. The integration of LiDAR data in this study was key to identify Spanish firs in the overflown area. The high biodiversity of Sierra de las Nieves made very difficult distinguishing species through their spectral signature, but LiDAR allowed us to detect the ‘pinsapos’ (Spanish firs) by discriminating the individuals below 8 meters height. The calculation of numerous vegetation indexes (NDVI, GNDVI, NDRE, MSR, WDRVI, SAVI and NGRDI) allowed characterizing the forest mass according to its vigor. After carrying out a statistical analysis of the degree of histogram separation for the different types of damage, it was determined that the GNDVI is the index that fits the most. After the reclassification of damage types, a map of the health status of the ‘pinsapar’ was obtained. The results obtained validated the methodology followed when enabling the low cost air vehicle, and allowed classifying the health status of the pinsapar in the study area, a formation of high ecological value.Se habilitó un paratrike para la captación de imágenes de alta resolución en formaciones de Abies pinsapo Boiss. Dicha formación se localiza en el P.N. Sierra de Las Nieves, en Parauta (Málaga). Se embarcaron, de forma simultánea, tres sensores, un RGB, un multiespectral y un térmico. Para ello se creó un acople para mantenerlos bien fijos al vehículo durante la ejecución del vuelo. El muestreo de campo fue estratificado y dirigido únicamente a individuos de pinsapos con la finalidad de producir una cartografía de defoliación y mortandad por la asociadas al hongo H. abietinum que provoca podredumbre radical, y al escolítido C. numidicus, que provoca muerte de las partes más altas por anillamiento del fuste. Los productos cartográficos obtenidos por el sensor Sequoia Parrot, fueron de alta calidad. No se puede decir lo mismo de los otros sensores incorporados, cómo es el caso del sensor térmico Gobi 640 GiGe, ya que por las dificultades encontradas durante el vuelo (turbulencias térmicas), no se llevó a cabo exhaustivamente el plan de vuelo predeterminado. La integración de datos LiDAR en este estudio fue necesaria para la detección de pinsapos en la zona sobrevolada. Al encontrarnos en una zona con muy alta biodiversidad, fue muy complicado distinguir entre especies a través de su firma espectral. Es por ello que, la información LiDAR hizo posible la detección de los pinsapos, discriminando todos los individuos que se encontraran por debajo de los 8 metros de altura. El cálculo de numerosos índices de vegetación, permitió caracterizar la masa forestal según su vigorosidad. Tras llevar a cabo un análisis estadístico del grado de separación de los histogramas de las distintas clases de daños, se determinó que el GNDVI es el índice que mayor se ajusta. Tras la reclasificación a clases de daños se obtuvo un mapa del estado sanitario del pinsapar. Los resultados obtenidos validaron la metodología seguida y permitieron clasificar el estado sanitario en el que se encuentra el pinsapar de la zona de estudio, tratándose de una formación de alto valor ecológico con un 28.88% de afectación por pagas y enfermedades
Sintering behaviour of steatite materials with barium carbonate flux
Steatite porcelains show excellent properties for insulating applications. New applications as small insulators for halogen bulbs lighting for
instance, place increasing demands on material performance. The purpose of this work is to study the sintering behaviour and microstructural
development of steatite ceramics formulated with BaCO3 flux. Both constant heating rate and isothermal sintering experiments together with
microstructure characterization have revealed important differences related to the presence of BaCO3 and different amounts of clay. Increasing the
amount of clay leads to higher vitreous/crystalline phase ratios but also to smaller grain sizes. This result is interesting because of the relevant role
played by the grain size for the protoenstatite to clinoenstatite transformation, which in turns is the origin of material aging and degradation.Peer reviewe
Reducción de los requerimientos de hemoderivados en el trasplante hepático con aprotinina
Prophylactic use of aprotinin during surgery has a beneficial effect on hemostatic mechanisms, reducing the need for blood products. A reduction in fibrinolysis seems to contribute to this effect
Dosis bajas de haloperidol en combinación con ondansetrón no son eficaces para la profilaxis de náuseas y vómitos postoperatorios en pacientes propicios a esta complicación
Introducción
El objetivo de este estudio fue evaluar la eficacia y los efectos secundarios de distintas combinaciones de antieméticos para la profilaxis de náuseas y vómitos postoperatorios (NVPO) en pacientes propicios a presentarlos tras cirugía muy emetógena.
Métodos
Tras revisar retrospectivamente las historias clínicas de pacientes sometidos a cirugía electiva muy emetógena bajo anestesia general durante el periodo 2009 a 2011, seleccionamos 368 mujeres con puntuación de Apfel ≥3 y que recibieron una combinación de 2 antieméticos como profilaxis. Analizamos la incidencia de NVPO a las 2, 6, 12 y 24 h del postoperatorio, rescates antieméticos, patrón de aparición de NVPO, efectos secundarios y nivel de sedación. Valoramos la respuesta completa como ausencia de NVPO en las primeras 24 h.
Resultados
Ondansetrón 4 mg i.v. en combinación con dexametasona 8 mg i.v. (O&Dex), haloperidol 1 mg i.v. (O&Hal1), haloperidol 2 mg i.v. (O&Hal2) o droperidol 1,25 mg i.v. (O&Dro) fueron las combinaciones más empleadas. La respuesta completa fue mayor en los grupos O&Dex: 68,5% (IC: 58-78); O&Hal2: 64,1% (IC: 53-74) y O&Dro 63% (IC: 52-73) que en el grupo O&Hal1: 41,3% (IC: 31-52) (p < 0,01). La máxima incidencia de NVPO ocurrió entre las 2 y 6 h del postoperatorio. La incidencia de efectos secundarios fue mayor en el grupo O&Hal2.
Conclusiones
En pacientes con elevado riesgo de NVPO sometidos a cirugía muy emetógena, la eficacia de dosis bajas de haloperidol (1 mg) en combinación con ondansetrón es escasa. Dosis mayores (2 mg) son altamente eficaces, pero se asocian a una alta incidencia de efectos secundarios.Background
In this observational study we reviewed the efficacy and side effects of different antiemetic combinations used in our hospital for postoperative nausea and vomiting (PONV) prophylaxis in high-risk women undergoing highly emetogenic surgery.
Methods
After reviewing retrospectively the medical records of patients undergoing highly emetogenic elective surgeries under general anaesthesia, we selected 368 women whose Apfel risk score was ≥ 3 and receiving a combination of 2 antiemetics for PONV prophylaxis. We analysed the incidence of PONV at 2, 6, 12 and 24 h after surgery, antiemetic rescue requirements, pattern of occurrence of PONV, side effects and level of sedation were also assessed. The main goal was complete response defined as no PONV within 24 h after surgery.
Results
Ondansetron 4 mg i.v. plus dexamethasone 8 mg i.v. (O&Dex), haloperidol 1 mg i.v. (O&Hal1), haloperidol 2 mg i.v. (O&Hal2) or droperidol 1.25 mg i.v. (O&Dro) were the combinations most frequently used. The complete response was better in groups O&Dex: 68.5% (CI: 58-78), O&Hal2: 64.1% (CI: 53-74) and O&Dro 63% (CI: 52-73) than in group O&Hal1: 41.3% (CI: 31-52) (p < 0,01). Peak incidence of PONV occurred within the 2-6 h period. The incidence of side effects was higher in group O&Hal2.
Conclusion
In high risk patients for PONV who underwent highly emetogenic surgeries, the efficacy of low-dose haloperidol (1 mg) in combination is limited. Higher doses (2 mg) are more effective but its use is associated with a high incidence of side effects
Depresión del sistema mononuclear-fagocítico provocada por altas dosis de morfínico
We evaluated in human monocytes the effect of high doses of alfentanyl on the expression of vimentin filaments, the phagocytic activity and the membrane display of HLA-DR molecules in the subjects undergoing surgery. The study was performed on 30 patients, ASAI-II. The patients received 100 mcg/kg i.v. of Alfentanil and the maintenance of anaesthesia was made with Alfentanil (2-3 mcg/kg/min.). The patients were randomized in two groups. The patients were ventilated with N2O:O2 (1:1) (Group I) or air: O2 (1:1) (Group II). After surgery, all patients of the Group II received Naloxone (0.2-0.4 mg). Central venous blood samples were obtained before induction, one and two hours after induction of anaesthesia and at the end of surgery. Separation of monocytes was performed according to Boyum technique. CD35 and HLA-DR molecules and vimentin filaments were studied by indirect immunofluorescence method using monoclonal antibodies. Percentage of positive cells were read with a cytofluorometer. The phagocytic function of monocytes was determined by ingestion of latex particles. Cortisol and ACTH plasma levels were determined by RIA. High doses of Alfentanyl depress phagocytic function and membrane display of CD35 and HLA-DR molecules in monocyte and induce marked changes in the organization of vimentin filaments in these cells in patients undergoing surgery. This monocytic depression was more marked in the patients ventilated with N2O. In our results there was uninhibition of ACTH and cortisol plasma levels responses to surgical stress by Alfentanil administration. Since the effects of Alfentanil were reversed by Naloxone, an opioid receptor mechanism seems to mediate these event