Estimating the rapid haemodynamic effects of passive leg raising in critically ill patients using bioreactance.

BACKGROUND: Rapid detection of changes in cardiac index (CI) in real time using minimally invasive monitors may be of clinical benefit. We tested whether the Starling-SV bioreactance device, which averages CI over a short 8 s period, could assess the effects of passive leg raising (PLR), a clinical test that is recommended to assess fluid responsiveness during septic shock. METHODS: In 32 critically ill patients, we measured CI by transpulmonary thermodilution (PiCCO2, CItd), pulse contour analysis (PiCCO2, CIPulse), and the Starling-SV device (CIStarling) at baseline. CIPulse and CIStarling were measured again at the end of a PLR test. In the 13 patients with a positive PLR test, CItd, CIPulse, and CIStarling were measured before and after a 500 ml saline infusion. The primary outcome was relative changes from baseline measurements in CItd, CIPulse, and CIStarling. Secondary outcomes compared absolute values measured by each method. RESULTS: Relative changes in CIPulse and CItd were significantly correlated (r=0.82; n=45; P<0.001), with an 89% concordance rate (n=45 paired measurements). Relative changes in CIStarling and CItd were also significantly correlated (r=0.59; n=45; P<0.001) with a 78% concordance rate. For absolute measures of CI (n=77 paired measurements), the bias between CIPulse and CItd was 0.01 L min-1 m-2 (limits of agreement, -0.49 and 0.51 L min-1 m-2; 15% percentage error). Bias between CIStarling and CItd was 0.03 L min-1 m-2 (limits of agreement, -1.61 and 1.67 L min-1 m-2; 48% percentage error). CONCLUSIONS: In critically ill patients, a non-invasive bioreactance device with a shorter averaging period assessed a passive leg raising test with reasonable accuracy.

Spin-valley polarization and tunneling magnetoresistance in monomer, dimer, and trimer magnetic silicene superlattices.

Monomer, dimer and trimer semiconductor superlattices are an alternative for bandgap engineering due to the possibility of duplicate, triplicate, and in general multiply the number of minibands and minigaps in a specific energy region. Here, we show that monomer, dimer, and trimer magnetic silicene superlattices (MSSLs) can be the basis for tunable magnetoresistive devices due to the multiplication of the peaks of the tunneling magnetoresistance (TMR). In addition, these structures can serve as spin-valleytronic devices due to the formation of two well-defined spin-valley polarization states by appropriately adjusting the superlattice structural parameters. We obtain these conclusions by studying the spin-valley polarization and TMR of monomer, dimer, and trimer MSSLs. The magnetic unit cell is structured with one seed A with positive magnetization, and one, two, or three seeds B with variable magnetization. The number of B seeds defines the monomer, dimer, and trimer superlattice, while its magnetic orientation positive or negative the parallel (PM) or antiparallel magnetization (AM) superlattice configuration. The transfer matrix method and the Landauer-Büttiker formalism are employed to obtain the transmission and transport properties, respectively. We find multiplication of TMR peaks in staircase fashion according to the number of B seeds in the superlattice unit cell. This multiplication is related to the multiplication of the minibands which reflects as multiplication of the descending envelopes of the conductance. We also find well-defined polarization states for both PM and AM by adjusting asymmetrically the width and height of the barrier-well in seeds A and B.

Tunneling magnetoresistance and spin-valley polarization of aperiodic magnetic silicene superlattices.

Magnetic silicene superlattices (MSSLs) are versatile structures with spin-valley polarization and tunneling magnetoresistance (TMR) capabilities. However, the oscillating transport properties related to the superlattice periodicity impede stable spin-valley polarization states reachable by reversing the magnetization direction. Here, we show that aperiodicity can be used to improve the spin-valley polarization and TMR by reducing the characteristic conductance oscillations of periodic MSSLs (P-MSSLs). Using the Landauer-Büttiker formalism and the transfer matrix method, we investigate the spin-valley polarization and the TMR of Fibonacci (F-) and Thue-Morse (TM-) MSSLs as typical aperiodic superlattices. Our findings indicate that aperiodic superlattices with higher disorder provide better spin-valley polarization and TMR values. In particular, TM-MSSLs reduce considerably the conductance oscillations giving rise to two well-defined spin-valley polarization states and a better TMR than F- and P-MSSLs. F-MSSLs also improve the spin-valley polarization and TMR, however they depend strongly on the parity of the superlattice generation.

Non-cardiac arterial disease in Catalonia: patient profiles and quality of clinical records by characteristics of the Vascular Surgery Unit.

AIM: Non-cardiac arterial disease (NCAD) is a frequent cause of hospital admission. The aim of this study was to investigate differences in patient profiles and clinical records as a function of the size of the Vascular Surgery Unit (VSU). METHODS: Retrospective observational study. Stratified cluster sampling and selection of patients hospitalized for NCAD. ANALYSIS: 1) description of patient profiles, quality of clinical records, and VSU [availability of diagnostic (DR) and therapeutic (TR) resources, and of written protocols (WP)]; 2) association between these variables and size of VSU. RESULTS: The sample consisted of 14 hospitals, 6 with a VSU of 15 or fewer beds (VSU < or = 15B) and 8 with >15 beds (VSU >15B). The mean number of DRs, TRs and WPs was 9, 2.8 and 2 in VSUs < or = 15B, and 11.5, 6.5 and 3.3 in VSUs >15B. The proportion of patients older than 70, female, with ischemic disease, or with coexisting diabetes was significantly higher in VSUs < or = 15B (67%, 31%, 95% and 57%, respectively) than in VSUs >15B (58%, 22%, 69% and 48%). Comorbid conditions and treatment during admission and at discharge were documented significantly less frequently in the clinical records in VSUs < or = 15B. Risk factors were under-reported in the clinical records of both types of VSU. CONCLUSION: Patient profiles and the quality of clinical records vary by size of VSU. Under-reporting of risk factors may hinder the implementation of prevention and treatment measures.

[The efficiency (cost-effectiveness) of palivizumab as prophylaxis against respiratory syncytial virus infection in premature infants with a gestational age of 32-35 weeks in Spain]. / La eficiencia (coste-efectividad) de palivizumab como profilaxis para la infección por virus respiratorio sincitial en prematuros de 32-35 semanas en España.

OBJECTIVES: To evaluate the efficiency (cost-effectiveness) of palivizumab in preventing severe respiratory syncytial virus (RSV) infection in premature infants with a gestational age of 32-35 weeks (GA 32-35) and two or more risk factors (RF) in Spain. DESIGN: decision tree model using data from the scientific literature and the FLIP I and FLIP II studies (cohort of 326 infants with GA 32-35 and two or more RF who received palivizumab) sponsored by the Spanish Society of Neonatology. Main effectiveness measure: quality-adjusted life years (QALY) gained. PERSPECTIVES: the national health service (NHS), which includes direct costs (administration of palivizumab and hospital admissions), and the societal perspective, which also includes indirect costs (the child's future lost productivity). Discount: 3 % annually for effectiveness and indirect costs. Sensitivity analysis: construction of 37 scenarios modifying variables related to effectiveness and costs. RESULTS: Prophylaxis with palivizumab in premature infants with GA 32-35 and two or more RF produced an incremental cost-effectiveness ratio (ICER) of 13,849 euro/QALY from the NHS perspective, and an ICER of 4,605 euro/QALY from the societal perspective. In the sensitivity analysis, from the NHS perspective the ICER ranged from 5,351 euro/QALY (most favorable scenario) to 23,276 euro/QALY (least favorable scenario). CONCLUSIONS: Palivizumab is a cost-effective therapy as prophylaxis against RSV in infants with GA 32-35 and two or more RF. Its use is efficient from the NHS perspective, since the cost of a QALY, even in the least favorable scenarios, is lower than the threshold of 30,000 Euro/QALY considered socially acceptable in Spain.

Anisakis physeteris y Pseudoterranova decipiens en el pez Mugil Curema comercializado en Tumaco, Colombia / Anisakis physeteris and Pseudoterranova decipiens in the Mugil curema fish caught in Tumaco, Colombia

RESUMEN Objetivo. Identificar nematodos de la familia Anisakidae en el pez de consumo Mugil curema. Materiales y métodos. Para este estudio, se recolectaron 16 peces Lisa (M. curema) del puerto de Tumaco, una ciudad en la costa colombiana del Pacífico. La identificación morfológica de las larvas se realizó mediante taxonomía clásica y se calculó el porcentaje de infestación de larvas. Para la identificación molecular, se realizó una PCR múltiple con cebadores para las especies Anisakis physeteris, Pseudoterranova decipiens, Anisakis simplex sensu stricto, Contracaecum osculatum, Hysterothylacium aduncum y Anisakis pegreffii. Resultados. La revisión taxonómica permitió la identificación de larvas de tipo II del género Anisakis y larvas del género Pseudoterranova. Las larvas se aislaron principalmente del intestino, donde se encontró que el 94% de los peces estaban parasitados por nematodos anisakidos. La PCR multiplex permitió la identificación de la especie A. physeteris (Larva tipo II) y P. decipiens. Conclusiones. Este estudio es el primer reporte de nematodo Anisakidae en Tumaco, Colombia. Estos resultados proporcionan una justificación convincente para un estudio adicional sobre la familia Anisakidae en Colombia, como un problema de salud pública.

ABSTRACT Objective: Identification nematodes Anisakidae family in Mugil curema fish. Materials and methods: For this study, 16 Lisa fish (Mugil curema) were obtained from the port of Tumaco, a city on the Colombian Pacific coast. Morphological identification of larvae was made by classical taxonomy and the percentage of larval infestation was calculated. For molecular identification, a multiplex PCR was carried out with primers for six species, Anisakis physeteris, Pseudoterranova decipiens, Anisakis simplex sensu stricto, Contracaecum osculatum, Hysterothylacium aduncum and Anisakis pegreffii. Results: The taxonomic revision enabled the identification of type II larvae of the genus Anisakis and larvae of the genus Pseudoterranova. The larvae were isolated mainly from the intestine, where it was found that 94% of the fish were parasitized by anisakid nematodes. The multiplex PCR enabled the identification of the species A. physeteris (Larva type II), and P. decipiens. Conclusions: This study is the first report of nematode Anisakidae on Tumaco, Colombia. These results provide a compelling justification for further study into the Anisakidae family in Colombia, as a public health problem.

Gastrointestinal complications associated with cardiopulmonary bypass procedures.

Gastrointestinal complications after cardiopulmonary bypass (CPB) procedures are rare, but when they do occur, they carry a significant incidence of morbidity and mortality. Over a 5-year period spanning 1988-1992, 4923 CPB procedures were performed and 64 patients were identified who suffered a GI complication, giving an incidence of 1.3 per cent. The most frequent complications were GI bleeding (40%) and pancreatitis (34%). Other complications included acute cholecystitis (11%), perforated duodenal ulcer (8%), ischemic bowel (5%), and diverticulitis (2%). Complications occurred most frequently in patients undergoing procedures with longer pump and cross-clamp times, such as valvular and combination (CABG/valve) procedures. Redo procedures and the use of an intra-aortic balloon pump increased the risk of developing a GI complication 2.5 and 12 times, respectively. Patients were treated aggressively both medically and surgically, but suffered a higher mortality (16%) as compared to those not suffering a GI complication (3%). We conclude that GI complications after CPB procedures are infrequent but lethal. Clinical features are often subtle, and a high index of suspicion is needed for early diagnosis and aggressive treatment.

Noniatrogenic pediatric vascular trauma: a ten-year experience at a level I trauma center.

We retrospectively reviewed all pediatric patients (< 18 years old) who presented to a Level I trauma center from 1984 to 1994 with noniatrogenic vascular trauma. There were 48 patients (42 male and 6 female) ages 2 to 17 years. Mechanism of injury included gunshot wounds (34) stab wounds (10), and blunt trauma (4). The lower extremities were most commonly injured (31), followed by upper extremity (17), trunk (8), and neck (4). Twenty-one (44%) patients had associated nonvascular injuries (primarily orthopedic or peripheral nerve). Eighteen (37%) patients underwent preoperative angiography for suspected extremity (15) or carotid injuries (3). Twenty-nine patients went to surgery without angiography based on severe ischemia (11) or hemorrhage (18). Arterial injuries (45) were managed by interposition reverse saphenous vein graft (16), primary repair (15), ligation (5), or other operative (5) and nonoperative treatment (4). Venous injuries (15) were treated with primary repair (8), patch (3), ligation (3), and nonoperative management (1). Fasciotomy was performed in six (12%). There were three deaths (6%), all due to aortic and/or caval injuries. Limb salvage in survivors was 100 per cent. There were no complications from angiography. Postoperative duplex scans demonstrated patency in six of the seven patients studied with venous injuries. We conclude that 1) noniatrogenic pediatric vascular trauma is uncommon, and 2) using an aggressive approach to both the diagnosis and treatment of these injuries can achieve excellent limb salvage rates with a low morbidity and mortality.

[Methods of investigation in clinical cardiology. VIII. Socioeconomic evaluation of clinical cardiology practice]. / Métodos de investigación en cardiología clínica (VIII). Evaluación socioeconómica de la práctica clínica cardiológica.

Health services are systems whose mission is to improve the health status of both individuals and society in general. In recent decades, these systems have faced challenges such as their increasing complexity, limited resources, rapid innovation and diffusion of medical technologies, pressures on demand from society and professionals, and the lack of knowledge of the effects of these factors on costs and society's health. In addition, health care expenditures have grown twice as fast as wealth in industrialized countries during the last 25 years. These problems have prompted cost containment as a key issue in health policy and, at the same time, have promoted the development of socioeconomic evaluation as a scientific activity in the frame of health services research. Socioeconomic evaluation tries to determine if the sacrifice made by society, which devotes part of its limited resources to health care, maximizes the outcomes for population. This article describes basic concepts and methods of economic appraisal in health services which are illustrated with examples of clinical practice in cardiology. Common methods of evaluation are described; the relation between the clinical outcome of a procedure and its associated costs is emphasized in explaining the types of efficiency analysis (cost-efficacy, cost-effectiveness, cost-utility, and cost-benefit); and finally a guide for socioeconomic evaluation is provided.

[The libraries of the public hospitals in Spain. An economic analysis. The Research Group on Libraries]. / Las bibliotecas de los hospitales públicos en España. Un análisis económico. Grupo de Investigación en Bibliotecas.

BACKGROUND: The continuous increase in scientific knowledge in the health field, the development of new technologies and the rising cost of publications means that libraries are essential for patient care, medical education and research. In Spain some deficiencies have been seen in hospital libraries, and their cost is unknown. OBJECTIVE: To analyze the cost of public hospital libraries in Spain and to estimate the cost of adapting them to international standards. METHODS: Cross-sectional survey of public hospitals larger than 100 beds, or smaller public hospitals with teaching accreditation. Information on the variables of interest was collected by questionnaire mailed to the libraries and followed up by telephone. Data collection was completed in 1996. The information on costs is for 1994. A sensitivity analysis was done to examine the effects of imprecise estimates and assumptions. RESULTS: Of the 314 hospitals identified, 211 (67.2%) had libraries. The 1994 cost of the of the 211 libraries was 3,060 million pesetas (mean cost: 14.5 million pesetas). Personnel costs were the most important item (38% of the total), followed by the cost of subscriptions (29%). The cost of hospital libraries represented 0.08% of national public expenditures on health. The cost of correcting inadequacies in accordance with international standards would increase spending by about 400 million pesetas the first year (0.01% of public spending on health). CONCLUSIONS: The cost of hospital libraries represents only a small fraction of public spending on health. Correction of the observed deficiencies and the importance of libraries in the health system would require increasing spending to about 0.1% of public spending on health.

[Primary prevention actions in AIDS and sexually transmitted diseases in adolescents]. / Acciones de prevencion primaria en sida y enfermedades de transmision sexual en adolescentes.

Considering primary prevention of ETS a priority in Adolescent Health care, we decided to investigate knowledge and attitudes of 205 students in relation to these pathologies. Results were used to organize an educational proposal based on groupal training of ¿¿Youth Health Promotors''. It is also shown the necessity of joint work between family and school in order to think and revise together with the young people involved, themes and values, in order to make a coherent, creative and holistic approach to human sexuality.

[Cost of childhood asthma in Spain: a cost evaluation model based on the prevalence]. / Coste del asma en pediatría en España: un modelo de evaluación de costes basado en la prevalencia.

INTRODUCTION: Asthma is the most common chronic disease in childhood, reduces the quality of life of children and their families, and produces high social and health care costs. In Spain, the cost of managing paediatric asthma is unknown. OBJECTIVE: To estimate the cost of managing paediatric asthma in Spain and to examine its variability depending on asthma severity. PATIENTS AND METHODS: The cost of asthma in children under 16 years in 2008 was estimated by building a costs assessment model including the factors that influence the cost of asthma in children: prevalence, distribution of disease severity, age, frequency of resources use depending on severity, and the cost of each resource. A sensitivity analysis was conducted to evaluate the underlying uncertainty depending on the variability of the estimators of resource use, the unit cost of each resource, and the prevalence. RESULTS: According to the model, the total cost of paediatric asthma in Spain is around 532 million euros, with a range of 392 to 693 million euros. Direct costs (health care costs) represent 60% of the total costs, and indirect costs (carer time), 40%. The mean annual cost per child with asthma is 1,149 euros, ranging from 403 euros for the mildest category of the disease to 5,380 euros for the most severe. CONCLUSIONS: The cost of paediatric asthma in Spain is very high and depends on disease severity. Although the most important costs are for the health care system, indirect costs are not negligible.

[Quality of life of preterm infants and admissions due to respiratory infections]. / Calidad de vida en lactantes nacidos prematuros según ingresos por infección respiratoria.

INTRODUCTION: Study of the association between lower respiratory tract infection hospitalisations and health related quality of life (HRQoL) in preterm infants of 32-35 weeks of gestational age. METHODS: Survey study nested into a prospective follow-up cohort study of preterm infants (FLIP-2). During the last FLIP-2 visit, 216 preterm-parent pairs were interviewed. The structured questionnaire included measures of HRQoL (QUALIN modified scale for the infant, and SF-12 for the parent, and Visual scales for both), caregiver overload (Zarit modified scale and indirect measurements). RESULTS: From October 2006 to March 2007 (RSV season), there were 71 respiratory hospitalisations (33%). Triplets and infants living in homes with >5 inhabitants were most likely to be hospitalised. Parents of hospitalised children were most likely, to have more and longer times off work for child care (47% vs. 18%), to have higher overload, and to obtain lower values in the physical dimension of SF-12. Multiple regression model associated infant HRQoL with higher gestational age, having 0-3 year-old siblings, being recommended palivizumab and had received it, lower caregiver overload, higher caregiver mental HRQoL and no absence from work for child care. CONCLUSIONS: Although respiratory hospitalisations were not associated with infant HRQoL, caregivers' HRQoL and overload were. Preterm infant HRQoL is associated with their caregivers' HRQoL and overload, and with receiving RSV prophylaxis when their risk profile recommends it.

Cryptosporidium spp, comparative diagnosis and geospatial distribution in diarrheic calves from dairy farms, Valdivia, Chile / Diagnóstico comparativo y distribución geoespacial de Cryptosporidium spp, en terneros diarreicos en lecherías de Valdivia, Chile

Objective. To determine the Cryptosporidium spp. infection frequency by using Ziehl-Neelsen and Auramine stains on samples obtained from diarrheic calves from milking farms of the Valdivia province. To compare both diagnostic tests and to determine the geospatial distribution of the infections caused by this protozoan. Materials and methods. 221 fecal samples of diarrheic calves of 24 milking farms of the Valdivia province were studied. The processing and analysis of the samples was done by Ziehl-Neelsen (ZN) and Auramine (AU) staining techniques, and the results were compared by McNemar statistical test and the concordance level was determined by kappa index. A map was also generated to determine the geospatial distribution of Cryptosporidium infections. Results. 57.9% of all the animals tested were classified as positive with the ZN stain test, while 55.6% of all the animals turned out positive for the AU stain test. The McNemar test showed no significant difference between both diagnostic techniques (p>0.05), while the kappa index showed proper concordance between tests (k=0.73). 100% of the farms studied showed protozoan presence demonstrating the broad distribution of the parasite, however, and considering the previous factor, it was not possible to determine geospatial associations for the parasite distribution. Conclusions. The infection frequency of Cryptosporidium is higher than 50% in the milking farms studied from the Valdivia province. No difference between the Ziehl-Neelsen and Auramine staining techniques was demonstrated showing very consistent results. It was possible to detect that the number of farms infected correspond to 100% of the farms analyzed.

Objetivo. Determinar la frecuencia de infección por Cryptosporidium spp., mediante las tinciones de Ziehl-Neelsen y Auramina en terneros diarreicos de predios lecheros de la provincia de Valdivia. Comparar ambas pruebas diagnósticas y determinar la distribución geoespacial de las infecciones causadas por este protozoo. Materiales y métodos. Se estudiaron 221 muestras fecales de terneros diarreicos pertenecientes a 24 predios de la provincia de Valdivia. El procesamiento y análisis de las muestras se realizó mediante tinción de Ziehl-Neelsen (ZN) y Auramina (AU); y ambas técnicas se compararon mediante la prueba estadística de McNemar y su nivel de concordancia se determinó mediante índice kappa. Se generó además un mapa para determinar la distribución geoespacial de las infecciones por Cryptosporidium. Resultados. Del total de animales muestreados, 57.9% resultaron positivos a ZN, mientras que 55.6% fueron positivo para AU. En la prueba de McNemar no hubo diferencia significativa entre los métodos diagnósticos estudiados (p>0.05), en tanto el índice kappa determinó una concordancia buena entre ambas pruebas (k=0.73). Del total de predios georeferenciados el 100% resultó positivo a la presencia del protozoo; demostrándose que ésta parasitosis tiene una amplia distribución; sin embargo, dado este factor, no fue posible determinar asociaciones geoespaciales sobre la distribución de éste. Conclusiones. La frecuencia de infección por Cryptosporidium supera el 50% en los predios lecheros de la provincia de Valdivia. No hubo diferencia entre las técnicas Ziehl-Neelsen y Auramina con resultados concordantes. Fue posible detectar que el número de predios infectados corresponde al 100% de los predios analizados.

Superoxide dismutase, catalase, and glutathione peroxidase in the testis of the Mexican big-eared bat (Corynorhinus mexicanus) during its annual reproductive cycle.

The reproductive physiology of Corynorhinus mexicanus includes a testes growth-involution cycle. Testis recrudescence begins in May-June, peaks in August and then undergoes a profound involution being totally regressed in November. Adult, male individuals were captured monthly during one year and ROS scavenging enzyme activities were measured in testes and expressed per total wet-weight and per mg protein. SOD total activity is very low from October to February; increases sharply one full month before testes recrudescence starts, and in August, when testis activity was at its peak, SOD is 3-4 times lower than in July. Catalase total activity is bimodal. The main peak of activity occurs during testicular recrudescence with an additional smaller peak, two months before the onset of recrudescence. Glutathione peroxidase total activity parallels almost exactly the testis growth cycle, increases in July, reaches a peak in August and decreases through September to almost disappear in October. SOD specific activity shows a pre-testicular increase of activity, maintains its activity from March to July and then descends drastically to almost nil in August, maintaining these low values until February. Catalase specific activity is particularly important during the period of testicular regression. GPX specific activity is low from March to July, months of testicular recrudescence; whereas its activity increases in August and peaks in November, when testes regression occurs. Our data show that ROS-scavenging enzymes may play a very important role during testes involution-recrudescence in C. mexicanus, and we believe their participation could be equally important in all seasonally breeding mammals.