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1.
Remote Sens Environ ; 211: 105-111, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33510546

RESUMEN

We use the recently released Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Version 4.1 (V4) lidar data to study the smoke plumes transported from Southern African biomass burning areas. Significant improvements in the CALIPSO V4 Level 1 calibration and V4 Level 2 algorithms lead to a better representation of their optical properties, with the aerosol subtype improvements being particularly relevant to smoke over this area. For the first time, we show evidence of smoke particles increasing in size, evidenced in their particulate color ratios, as they are transported over the South Atlantic Ocean from the source regions over Southern Africa. We hypothesize that this is due to hygroscopic swelling of the smoke particles and is reflected in the higher relative humidity in the middle troposphere for profiles with smoke. This finding may have implications for radiative forcing estimates over this area and is also relevant to the ORACLES field mission.

2.
J Clin Monit Comput ; 32(5): 817-823, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29204771

RESUMEN

The aim of this study was to evaluate the accuracy and precision of non-invasive continuous blood pressure measurement by applanation tonometry (AT) in awake or anaesthetised cardiological intensive care patients. Patients suffering from highly impaired left ventricular function atrial fibrillation or severe aortic valve stenosis were included into the study. Arterial blood pressure was recorded by applanation tonometry (T-Line 400, Tensys Medical®, USA) and an arterial line in awake or anaesthetised patients. Discrepancies in mean (MAP), systolic (SAP), and diastolic (DAP) arterial pressure between the two methods were assessed as bias, limits of agreement and percentage error respectively. In 31 patients a total of 27,900 measurements were analyzed. The concordance correlation coefficient was 0.23, 0.45 and 0.06 for MAP, SAP and DAP, respectively. For all patients bias for MAPAT compared to MAPAL was 14.96 mmHg (SAPAT 4.51 mmHg; DAPAT 19.12 mmHg) with limits of agreement for MAPAT of 46.25 and - 16.33 mm Hg (SAPAT 48.00 and - 38.98 mmHg; DAPAT 50.12 and - 11.89 mmHg). Percentage error for MAPAT was 56.8% (42.7% for SAPAT; 75.2% for DAPAT). We conclude that the AT method is not reliable in ICU patients with severe cardiac comorbidities.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Monitorización Hemodinámica/métodos , Manometría/métodos , Anciano , Estenosis de la Válvula Aórtica/fisiopatología , Presión Arterial/fisiología , Fibrilación Atrial/fisiopatología , Determinación de la Presión Sanguínea/estadística & datos numéricos , Unidades de Cuidados Coronarios , Cuidados Críticos , Femenino , Monitorización Hemodinámica/estadística & datos numéricos , Humanos , Masculino , Manometría/estadística & datos numéricos , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Disfunción Ventricular Izquierda/fisiopatología , Análisis de Ondículas
3.
Anaesthesist ; 67(10): 780-789, 2018 10.
Artículo en Alemán | MEDLINE | ID: mdl-30203329

RESUMEN

Central venous pressure (CVP) is deemed to be an important parameter of anesthesia management in liver surgery. To reduce blood loss during liver resections, a low target value of CVP is often propagated. Although current meta-analyses have shown a connection between low CVP and a reduction in blood loss, the underlying studies show methodological weaknesses and advantages with respect to morbidity and mortality can hardly be proven. The measurement of the CVP itself is associated with numerous limitations and influencing factors and the measures to reduce the CVP have been insufficiently investigated with respect to hepatic hemodynamics. The definition of a generally valid target area for the CVP must be called into question. The primary objective is to maintain adequate oxygen supply and euvolemia. The CVP should be regarded as a mosaic stone of hemodynamic management.


Asunto(s)
Presión Venosa Central/fisiología , Hígado/cirugía , Pérdida de Sangre Quirúrgica/prevención & control , Determinación de la Presión Sanguínea , Hemodinámica , Hepatectomía/métodos , Humanos , Hígado/irrigación sanguínea , Oxígeno/administración & dosificación , Oxígeno/sangre
4.
Br J Anaesth ; 118(1): 68-76, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28039243

RESUMEN

BACKGROUND: Functional imaging by thoracic electrical impedance tomography (EIT) is a non-invasive approach to continuously assess central stroke volume variation (SVV) for guiding fluid therapy. The early available data were from healthy lungs without injury-related changes in thoracic impedance as a potentially influencing factor. The aim of this study was to evaluate SVV measured by EIT (SVVEIT) against SVV from pulse contour analysis (SVVPC) in an experimental animal model of acute lung injury at different lung volumes. METHODS: We conducted a randomized controlled trial in 30 anaesthetized domestic pigs. SVVEIT was calculated automatically analysing heart-lung interactions in a set of pixels representing the aorta. Each initial analysis was performed automatically and unsupervised using predefined frequency domain algorithms that had not previously been used in the study population. After baseline measurements in normal lung conditions, lung injury was induced either by repeated broncho-alveolar lavage (n=15) or by intravenous administration of oleic acid (n=15) and SVVEIT was remeasured. RESULTS: The protocol was completed in 28 animals. A total of 123 pairs of SVV measurements were acquired. Correlation coefficients (r) between SVVEIT and SVVPC were 0.77 in healthy lungs, 0.84 after broncho-alveolar lavage, and 0.48 after lung injury from oleic acid. CONCLUSIONS: EIT provides automated calculation of a dynamic preload index of fluid responsiveness (SVVEIT) that is non-invasively derived from a central haemodynamic signal. However, alterations in thoracic impedance induced by lung injury influence this method.


Asunto(s)
Lesión Pulmonar Aguda/fisiopatología , Impedancia Eléctrica , Fluidoterapia , Volumen Sistólico , Tomografía/métodos , Animales , Respiración con Presión Positiva , Porcinos
5.
Br J Anaesth ; 116(6): 790-6, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27095239

RESUMEN

BACKGROUND: The aim of this study was to evaluate the validity of non-invasive continuous BP measurement by applanation tonometry in morbidly obese patients undergoing bariatric surgery. METHODS: Arterial blood pressure (AP) was recorded intraoperatively both by applanation tonometry (AT) (T-Line 200pro, Tensys Medical(®), USA) and an arterial line (AL) after radial cannulation in obese patients undergoing bariatric surgery. Discrepancies between the two methods were assessed as bias, limits of agreement and percentage error. Mean, systolic, and diastolic arterial pressures were assessed (MAP, SAP, DAP respectively). Trending ability was assessed by concordance based on four-quadrant plotting. RESULTS: Mean (sd) BMI of the 28 patients was 49.4 (9.7 kg m(-2)). A total of 201 907 time points were available for analysis. Bias for MAPAT compared with MAPAL was +3.97 mm Hg (SAPAT +3.45 mm Hg; DAPAT +3.66 mm Hg) with limits of agreement for MAPAT of -14.47 and +22.41 mm Hg (SAPAT -22.0 and +28.9 mm Hg; DAPAT -15.7 and +23.1 mm Hg). Percentage error for MAPAT was 23.5% (23.4% for SAPAT; 30.5% for DAPAT). Trending ability for MAP, SAP, and DAP revealed a concordance of 0.74, 0.72, and 0.71, respectively. CONCLUSIONS: Continuous BP assessment by applanation tonometry is feasible in morbidly obese patients undergoing bariatric surgery. However, despite a low mean difference, 95% limits of agreement and trending ability indicate that the technology needs to be improved further, before being recommended for routine use in this group of patients.


Asunto(s)
Presión Arterial , Cirugía Bariátrica/métodos , Determinación de la Presión Sanguínea/métodos , Manometría/métodos , Monitoreo Intraoperatorio/métodos , Obesidad Mórbida/fisiopatología , Obesidad Mórbida/cirugía , Adulto , Anciano , Índice de Masa Corporal , Cuidados Críticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Adulto Joven
6.
Br J Anaesth ; 117(2): 228-35, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27440635

RESUMEN

BACKGROUND: Lung-protective ventilation is claimed to be beneficial not only in critically ill patients, but also in pulmonary healthy patients undergoing general anaesthesia. We report the use of electrical impedance tomography for assessing regional changes in ventilation, during both spontaneous breathing and mechanical ventilation, in patients undergoing robot-assisted radical prostatectomy. METHODS: We performed electrical impedance tomography measurements in 39 patients before induction of anaesthesia in the sitting (M1) and supine position (M2), after the start of mechanical ventilation (M3), during capnoperitoneum and Trendelenburg positioning (M4), and finally, in the supine position after release of capnoperitoneum (M5). To quantify regional changes in lung ventilation, we calculated the centre of ventilation and 'silent spaces' in the ventral and dorsal lung regions that did not show major impedance changes. RESULTS: Compared with the awake supine position [2.3% (2.3)], anaesthesia and mechanical ventilation induced a significant increase in silent spaces in the dorsal dependent lung [9.2% (6.3); P<0.05]. Capnoperitoneum and the Trendelenburg position led to a significant increase in such spaces [11.5% (8.9)]. Silent space in the ventral lung remained constant throughout anaesthesia. CONCLUSION: Electrical impedance tomography was able to identify and quantify on a breath-by-breath basis circumscribed areas, so-called silent spaces, within healthy lungs that received little or no ventilation during general anaesthesia, capnoperitoneum, and different body positions. As these silent spaces are suggestive of atelectasis on the one hand and overdistension on the other, they might become useful to guide individualized protective ventilation strategies to mitigate the side-effects of anaesthesia and surgery on the lungs.


Asunto(s)
Posicionamiento del Paciente , Ventilación Pulmonar , Tomografía/métodos , Resistencia de las Vías Respiratorias , Anestesia General , Cuidados Críticos , Impedancia Eléctrica , Inclinación de Cabeza , Humanos , Masculino , Peritoneo/diagnóstico por imagen , Posición Prona , Prostatectomía , Atelectasia Pulmonar/diagnóstico por imagen , Respiración Artificial , Procedimientos Quirúrgicos Robotizados , Posición Supina
7.
Anaesthesist ; 64(7): 494-505, 2015 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-26081011

RESUMEN

Goal-directed hemodynamic therapy is becoming increasingly more interesting for anesthesiologists and intensive care physicians. Meta-analyses of studies evaluating perioperative therapy algorithms demonstrated a reduction of postoperative morbidity compared to the previous clinical practices. In this review article the basic concepts of goal-directed hemodynamic therapy and the principles of previously employed therapy algorithms are described and discussed. Furthermore, the questions of how these therapy strategies can be transferred into daily clinical practice and whether these therapeutic approaches might even bear risks for patients are elucidated.


Asunto(s)
Fluidoterapia/métodos , Hemodinámica/fisiología , Algoritmos , Gasto Cardíaco , Objetivos , Humanos , Atención Perioperativa , Complicaciones Posoperatorias/prevención & control , Resultado del Tratamiento
8.
Br J Anaesth ; 110(6): 957-65, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23462192

RESUMEN

BACKGROUND: It is unclear what factors affect the uptake of sevoflurane administered through the membrane oxygenator during cardiopulmonary bypass (CPB) and whether this can be monitored via the oxygenator exhaust gas. METHODS: Stable delivery of sevoflurane was administered to 30 elective cardiac surgery patients at 1.8 vol% (inspiratory) via the anaesthetic circuit and ventilator. During CPB, sevoflurane was administered in the oxygenator fresh gas supply (Compactflo Evolution™; Sorin Group, Milano, Italy). Sevoflurane plasma concentration (SPC) was measured using gas chromatography. Changes were correlated with bispectral index (BIS), patient temperature, haematocrit, plasma albumin concentration, oxygenator fresh gas flow, and the sevoflurane concentration in the oxygenator exhaust at predefined time points. RESULTS: The mean SPC pre-bypass was 54.9 µg ml(-1) [95% confidence interval (CI): 50.6-59.1]. SPC decreased to 43.2 µg ml(-1) (95% CI: 40.3-46.1; P<0.001) after initiation of CPB, and was lower still during rewarming and weaning from bypass, 39.4 µg ml(-1) (95% CI: 36.6-42.3; P<0.001). BIS did not exceed a value of 55. SPCs were higher during hypothermia (P<0.001) and with an increase in oxygenator fresh gas flow (P=0.015), and lower with haemodilution (P=0.027). No correlation was found between SPC and the concentration of sevoflurane in the oxygenator exhaust gas (r=-0.04; 95% CI: -0.18 to 0.09; P=0.53). CONCLUSIONS: The uptake of sevoflurane delivered via the membrane oxygenator during CPB seems to be affected by hypothermia, haemodilution, and changes in the oxygenator fresh gas supply flow. Measuring the concentration of sevoflurane in the exhaust from the oxygenator is not useful for monitoring sevoflurane administration during bypass.


Asunto(s)
Anestésicos por Inhalación/sangre , Procedimientos Quirúrgicos Cardíacos , Puente Cardiopulmonar , Éteres Metílicos/sangre , Oxigenadores de Membrana , Anciano , Anciano de 80 o más Años , Electroencefalografía , Femenino , Humanos , Masculino , Éteres Metílicos/administración & dosificación , Persona de Mediana Edad , Estudios Prospectivos , Sevoflurano
9.
Br J Anaesth ; 111(5): 736-42, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23811425

RESUMEN

BACKGROUND: Predicting the response of cardiac output to volume administration remains an ongoing clinical challenge. The objective of our study was to compare the ability to predict volume responsiveness of various functional measures of cardiac preload. These included pulse pressure variation (PPV), stroke volume variation (SVV), and the recently launched automated respiratory systolic variation test (RSVT) in patients after major surgery. METHODS: In this prospective study, 24 mechanically ventilated patients after major surgery were enrolled. Three consecutive volume loading steps consisting of 300 ml 6% hydroxyethylstarch 130/0.4 were performed and cardiac index (CI) was assessed by transpulmonary thermodilution. Volume responsiveness was considered as positive if CI increased by >10%. RESULTS: In total 72 volume loading steps were analysed, of which 41 showed a positive volume response. Receiver operating characteristic (ROC) curve analysis revealed an area under the curve (AUC) of 0.70 for PPV, 0.72 for SVV and 0.77 for RSVT. Areas under the curves of all variables did not differ significantly from each other (P>0.05). Suggested cut-off values were 9.9% for SVV, 10.1% for PPV, and 19.7° for RSVT as calculated by the Youden Index. CONCLUSION: In predicting fluid responsiveness the new automated RSVT appears to be as accurate as established dynamic indicators of preload PPV and SVV in patients after major surgery. The automated RSVT is clinically easy to use and may be useful in guiding fluid therapy in ventilated patients.


Asunto(s)
Presión Sanguínea/fisiología , Fluidoterapia/métodos , Cuidados Posoperatorios/métodos , Mecánica Respiratoria/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Resistencia de las Vías Respiratorias , Algoritmos , Anestesia General , Presión Arterial/fisiología , Automatización , Gasto Cardíaco/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Periodo Posoperatorio , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Volumen Sistólico/fisiología , Termodilución , Adulto Joven
10.
Br J Anaesth ; 108(6): 922-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22440313

RESUMEN

BACKGROUND: Cardiac output (CO) monitoring can be useful in high-risk patients during one-lung ventilation (OLV), but it is unclear whether thermodilution-derived CO monitoring is valid during OLV. Therefore, we compared pulmonary artery (CO(PATD)) and transcardiopulmonary thermodilution (CO(TPTD)) with an experimental reference in a porcine model. METHODS: CO(PATD) and CO(TPTD) were measured in 23 pigs during double-lung ventilation (DLV) and 15 min after the onset of OLV, during conditions of normovolaemia and after haemorrhage. An ultrasonic flow probe placed around the pulmonary artery (CO(PAFP)) was used for reference. RESULTS: The range of CO in these experiments was 1.5-3 litre min(-1). Normovolaemia: during DLV and conditions of normovolaemia, the mean (95% limits of agreement) bias for CO(PATD) compared with CO(PAFP) was -0.05 (-0.92 and 0.83) litre min(-1), and 0.58 (-0.40 and 1.55) litre min(-1) for CO(TPTD). During OLV, the bias for CO(PATD) remained unchanged at 0.08 (-0.51 and 0.66) litre min(-1), P=0.15, and the bias for CO(TPTD) increased significantly to 0.85 (0.05 and 1.64) litre min(-1), P=0.047. Hypovolaemia: during DLV, the bias for CO(PATD) compared with CO(PAFP) was 0.22 (-0.20 and 0.66) litre min(-1) and for CO(TPTD) was 0.60 (0.12 and 1.10) litre min(-1). There was no significant change of bias during OLV for CO(PATD) [0.30 (-0.10 and 0.70) (litre min(-1)), P=0.25] or bias CO(TPTD) [0.72 (0.21 and 1.22) (litre min(-1)), P=0.14]. Trending ability during OLV, quantified by the mean of angles θ, showed good values for both CO(PATD) (θ=11.2°) and CO(TPTD) (θ=1.3°). CONCLUSIONS: CO(TPTD) is, to some extent, affected by OLV, whereas CO(PATD) is unchanged. Nonetheless, both methods provide an acceptable estimation of CO and particularly of relative changes of CO during OLV.


Asunto(s)
Gasto Cardíaco , Respiración Artificial , Termodilución/métodos , Animales , Arteria Pulmonar/fisiología , Porcinos
11.
Br J Anaesth ; 106(5): 659-64, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21441547

RESUMEN

BACKGROUND: Predicting the response of cardiac output (CO) to volume administration remains difficult, in particular in patients with acutely compromised cardiac function, where, even small amounts of i.v. fluids can lead to volume overload. We compared the ability to predict volume responsiveness of different functional haemodynamic parameters, such as pulse pressure variation (PPV), stroke volume variation (SVV), the static preload parameter right atrial pressure (RAP), and global end-diastolic volume (GEDV) with the recently proposed respiratory systolic variation test (RSVT) in acutely impaired cardiac function. METHODS: In 13 mechanically ventilated pigs, cardiac function was acutely reduced by continuous application of verapamil to reach a decrease in peak change of left ventricular pressure over time (dP/dt) of 50%. After withdrawal of 20 ml kg(-1) BW blood to establish hypovolaemia, four volume loading steps of 7 ml kg(-1) BW using the shed blood and 6% hydroxyethylstarch 130/0.4 were performed. Volume responsiveness was considered as positive, if CO increased more than 10%. RESULTS: Receiver operating characteristic curve analysis revealed an area under the curve (AUC) of 0.88 for the RSVT, 0.84 for PPV, 0.82 for SVV, 0.78 for RAP, and 0.77 for GEDV. CONCLUSIONS: Functional parameters of cardiac preload, including the RSVT, allow prediction of fluid responsiveness in an experimental model of acutely impaired cardiac function.


Asunto(s)
Fluidoterapia , Disfunción Ventricular Izquierda/fisiopatología , Enfermedad Aguda , Animales , Presión Sanguínea/fisiología , Gasto Cardíaco/fisiología , Modelos Animales de Enfermedad , Hemodinámica/fisiología , Monitoreo Fisiológico/métodos , Respiración con Presión Positiva/métodos , Sus scrofa , Sístole/fisiología
12.
Chirurg ; 91(2): 121-127, 2020 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-32025774

RESUMEN

An appropriate perioperative infusion management is pivotal for the perioperative outcome of the patient. Optimization of the perioperative fluid treatment often results in enhanced postoperative outcome, reduced perioperative complications and shortened hospitalization. Hypovolemia as well as hypervolemia can lead to an increased rate of perioperative complications. The main goal is to maintain perioperative euvolemia by goal-directed therapy (GDT), a combination of fluid management and inotropic medication, to optimize perfusion conditions in the perioperative period; however, perioperative fluid management should also include the preoperative and postoperative periods. This encompasses the preoperative administration of carbohydrate-rich drinks up to 2 h before surgery. In the postoperative period, patients should be encouraged to start per os hydration early and excessive i.v. fluid administration should be avoided. Implementation of a comprehensive multimodal, goal-directed fluid management within an enhanced recovery after surgery (ERAS) protocol is efficient but the exact status of indovodual items remains unclear at present.


Asunto(s)
Fluidoterapia , Atención Perioperativa , Humanos , Periodo Perioperatorio , Complicaciones Posoperatorias/prevención & control , Periodo Posoperatorio
13.
Physiol Meas ; 39(2): 024002, 2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29350189

RESUMEN

OBJECTIVE: Electrical impedance tomography (EIT) is a non-invasive and radiation-free bedside monitoring technology, primarily used to monitor lung function. First experimental data shows that the descending aorta can be detected at different thoracic heights and might allow the assessment of central hemodynamics, i.e. stroke volume and pulse transit time. APPROACH: First, the feasibility of localizing small non-conductive objects within a saline phantom model was evaluated. Second, this result was utilized for the detection of the aorta by EIT in ten anesthetized pigs with comparison to thoracic computer tomography (CT). Two EIT belts were placed at different thoracic positions and a bolus of hypertonic saline (10 ml, 20%) was administered into the ascending aorta while EIT data were recorded. EIT images were reconstructed using the GREIT model, based on the individual's thoracic contours. The resulting EIT images were analyzed pixel by pixel to identify the aortic pixel, in which the bolus caused the highest transient impedance peak in time. MAIN RESULTS: In the phantom, small objects could be located at each position with a maximal deviation of 0.71 cm. In vivo, no significant differences between the aorta position measured by EIT and the anatomical aorta location were obtained for both measurement planes if the search was restricted to the dorsal thoracic region of interest (ROIs). SIGNIFICANCE: It is possible to detect the descending aorta at different thoracic levels by EIT using an intra-aortic bolus of hypertonic saline. No significant differences in the position of the descending aorta on EIT images compared to CT images were obtained for both EIT belts.


Asunto(s)
Aorta/diagnóstico por imagen , Tórax/irrigación sanguínea , Tomografía/métodos , Animales , Impedancia Eléctrica , Humanos , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Porcinos
14.
Aliment Pharmacol Ther ; 46(10): 981-991, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28940225

RESUMEN

BACKGROUND: Refractory ascites (RA) is a frequent complication of cirrhosis, requiring large volume paracentesis or placement of a transjugular intrahepatic portosystemic shunt (TIPSS). The automated low-flow ascites pump (alfapump, Sequana Medical AG, Zurich, Switzerland) is an innovative treatment option for patients with RA. AIM: To assess safety and efficacy of this treatment in patients with a contraindication to TIPSS. METHODS: Fifty-six patients (43 males; mean age 62 years) from centres in Germany, Switzerland, UK and Spain were included and followed for up to 24 months. Complications, device deficiencies, paracentesis frequency and patient survival were recorded. RESULTS: At the time of this analysis, 3 patients completed the 24-month observation period, monitoring of 3 was ongoing, 9 underwent liver transplantation, 17 patients were withdrawn due to serious adverse events and 23 patients died. Most frequently observed technical complication was blocking of the peritoneal catheter. Twenty-three pump-related reinterventions (17 patients) and 12 pump exchanges (11 patients) were required during follow-up. The pump system was explanted in 48% of patients (in 17 patients due to serious adverse events, in 9 at the time of liver transplantation and in 1 due to recovery from RA). Median frequency of paracentesis dropped from 2.17 to 0.17 per month. CONCLUSIONS: The alfapump can expand therapeutic options for cirrhotic patients with RA. Continuous drainage of ascites in a closed loop automated system led to significant reduction in paracentesis frequency. Technical and procedural improvements are required to reduce the rate of adverse events and reinterventions. https://clinicaltrials.gov/ct2/show/NCT01532427.


Asunto(s)
Ascitis/terapia , Cirrosis Hepática/complicaciones , Paracentesis/métodos , Derivación Portosistémica Intrahepática Transyugular/métodos , Ascitis/etiología , Drenaje/métodos , Femenino , Humanos , Trasplante de Hígado/métodos , Masculino , Persona de Mediana Edad
15.
Sportverletz Sportschaden ; 1(2): 81-5, 1987 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-3508012

RESUMEN

In a randomised study the anterior cruciate ligament (ACL) was resected in 16 sheep and replaced by a PTFE-Ligament prosthesis. The device was examined 1/2 year and 1 year after implantation. 1 year after implantation the signs of wear were considerably greater than 1/2 year after implantation and the tensile strength was significantly decreased. As a result of the implantation technique and by the large volume, the device underwent an unphysiologically high mechanical stress, leading to early breakage. The improved implantation technique should result in lower mechanical stress in the larger human knee joint and a longer lifetime should be expected.


Asunto(s)
Ligamentos Articulares/cirugía , Politetrafluoroetileno , Prótesis e Implantes , Animales , Fenómenos Biomecánicos , Falla de Prótesis , Ovinos
16.
Sportverletz Sportschaden ; 2(4): 172-7, 1988 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-3245033

RESUMEN

Epiphyseolysis of the proximal tibia is a most unusual injury. The case reports show that there was no adequate trauma leading to this damage. One has to argue, that disposition could be a predisposing factor. Therapy and prognosis of this injury are presented.


Asunto(s)
Traumatismos en Atletas/etiología , Epífisis Desprendida/etiología , Traumatismos de la Rodilla/etiología , Educación y Entrenamiento Físico , Adolescente , Traumatismos en Atletas/cirugía , Niño , Epífisis Desprendida/cirugía , Humanos , Traumatismos de la Rodilla/cirugía , Masculino , Factores de Riesgo
17.
Orthopade ; 37(8): 783-7, 2008 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-18629468

RESUMEN

BACKGROUND: This retrospective study was performed to investigate the clinical and radiological results after STAR total ankle replacement. MATERIAL AND METHODS: Between January 2000 and September 2004, 49 patients with an average age of 62.5 years underwent total ankle replacement with the STAR prosthesis. At an average follow-up of 30.4 months, 48 patients were examined clinically and radiologically. The Kofoed ankle score and the patients' subjective satisfaction were evaluated. RESULTS: The operation improved the Kofoed ankle score significantly, from 28 to 86 points, 90% of the patients were satisfied with the results. The revision rate was 10%. CONCLUSION: The early results after implantation of the STAR ankle prosthesis are encouraging. With correct indication, a high rate of pain reduction and patient satisfaction can be achieved. The long-term benefit of this procedure has yet to be determined.


Asunto(s)
Articulación del Tobillo/cirugía , Prótesis Articulares , Osteoartritis/cirugía , Vitalio , Adulto , Anciano , Articulación del Tobillo/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/diagnóstico por imagen , Satisfacción del Paciente , Cuidados Posoperatorios , Complicaciones Posoperatorias/diagnóstico por imagen , Diseño de Prótesis , Radiografía , Rango del Movimiento Articular , Reoperación
18.
Appl Opt ; 46(8): 1261-78, 2007 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-17318246

RESUMEN

The latest in a series of solar occultation satellite instruments, Stratospheric Aerosol and Gas Experiment (SAGE) III, was placed into orbit in December 2001, and data were obtained until March 2006. Measurements were made of the extinction attributable to aerosols and cloud at a number of wavelengths between 290 and 1550 nm. The analysis of data obtained by its predecessor, SAGE II, has shown that an intercomparison of such data at two or more wavelengths may be used to separate the effects of cloud and aerosol. This analysis has been done on a routine basis for many years using SAGE II data at 525 and 1020 nm and applied extensively to global studies of tropospheric cloud and aerosol. Here we describe the aerosol-cloud separation algorithm developed for use with the SAGE III data, which uses the extinction at 525, 1020, and 1550 nm. This algorithm is now being used to produce vertical profiles of cloud presence as a standard SAGE III data product. These profiles have a vertical resolution of 0.5 km and cover the altitude range from 6.0 to 30.0 km, and data are presently available from March 2002 onward. An outline is given of the development of this algorithm, the nature of the SAGE III data, and the algorithm performance. To maintain continuity with SAGE II cloud data, the relative performances of the SAGE II and SAGE III algorithms are also examined. An example of the application of the algorithm to SAGE III tropospheric data is shown and discussed.

19.
Arch Orthop Trauma Surg ; 126(1): 45-8, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16333631

RESUMEN

INTRODUCTION: Improving the longevity and reliability of cemented total knee arthroplasty (TKA) remains a major step to achieve. It is still unclear, whether a cemented tibial stem reduces micromotion of the tibial tray and produces therefore a better initial stability or not. The higher conformity of rotating platform design and the possible rotary forces to the tibial platform may produce higher micromotion when the tibial stem remains cementless (hybrid fixation). MATERIALS AND METHODS: An in vitro study was performed using the PFC mobile bearing tibial tray (DePuy, Warswa, IN, USA) to test the hypothesis that the addition of cement surrounding the tibial stem reduces micromotion of the tibial tray in cemented TKA with mobile bearing design. Ten tibial trays with mobile design were implanted in sawbones with a 3-mm cement mantle beneath the baseplate of the tibial tray and with or without the cemented stem. Tibial trays were loaded additionally in the ventral, lateral, medial and posterior positions with 2,500 N using the Zwick Z010 instrumentation and HBM pick up Hottinger Baldwin. RESULTS: In this study, a significant increased mean maximum liftoff was found when only cementing the tibial baseplate (hybrid fixation), compared to the fully cemented tibial tray (P<0.02). CONCLUSION: In conclusion, the stem of mobile bearing tibial components should be cemented to provide increased micromotion and earlier loosening.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Cementación/instrumentación , Análisis de Falla de Equipo , Fijadores Internos , Tibia/cirugía , Artroplastia de Reemplazo de Rodilla/métodos , Cementos para Huesos , Cementación/métodos , Humanos , Técnicas In Vitro , Diseño de Prótesis , Falla de Prótesis
20.
Knee Surg Sports Traumatol Arthrosc ; 14(7): 605-11, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16362360

RESUMEN

Mobile and fixed bearing in total knee replacement are still discussed controversially. In a retrospective, matched-pair study, we investigated 40 patients with computer-assisted (BrainLAB) primary total knee replacement (PFC Sigma, DePuy) performed two years before. Twenty patients each received a mobile bearing and a fixed bearing. We compared Womac Score, Knee Society Score, postoperative ROM, fluoroscopic measurement of knee stability in flexion and extension and isokinetic muscle strength using a Biodex-3 dynamometer. Both groups showed similar results concerning WOMAC Score (total rotating bearing: 23.05; fixed bearing: 22.57), KSS (rotating bearing: 174.89; fixed bearing: 176.1). Isokinetic muscle force demonstrated statistically significant superior results for knee flexion in the rotating bearing group. Medio-lateral stability revealed statistically significant superior results for the rotating bearing compared to fixed bearing in extension (P>0.05). In flexion only lateral stability was superior (P>0.05). Two-year clinical follow-up after computer-assisted total knee replacement resulted in good clinical outcome with high patient satisfaction. Statistically significant better values for the rotating platform group were found for the medio-lateral stability in extension and the peak flexion torque.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Inestabilidad de la Articulación/fisiopatología , Articulación de la Rodilla/fisiopatología , Prótesis de la Rodilla , Anciano , Fenómenos Biomecánicos , Femenino , Fluoroscopía , Estudios de Seguimiento , Humanos , Inestabilidad de la Articulación/cirugía , Articulación de la Rodilla/cirugía , Masculino , Análisis por Apareamiento , Fuerza Muscular/fisiología , Dinamómetro de Fuerza Muscular , Satisfacción del Paciente , Diseño de Prótesis , Rango del Movimiento Articular/fisiología , Estudios Retrospectivos , Cirugía Asistida por Computador , Resultado del Tratamiento
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