Guidelines for the prevention of ventilator-associated pneumonia and their implementation. The Spanish "Zero-VAP" bundle

BACKGROUND

"Zero-VAP" is a proposal for the implementation of a simultaneous multimodal intervention in Spanish intensive care units (ICU) consisting of a bundle of ventilator-associated pneumonia (VAP) prevention measures.

METHODS/DESIGN

An initiative of the Spanish Societies of Intensive Care Medicine and of Intensive Care Nurses, the project is supported by the Spanish Ministry of Health, and participation is voluntary. In addition to guidelines for VAP prevention, the "Zero-VAP" Project incorporates an integral patient safety program and continuous online validation of the application of the bundle. For the latter, VAP episodes and participation indices are entered into the web-based Spanish ICU Infection Surveillance Program "ENVIN-HELICS" database, which provides continuous information about local, regional and national VAP incidence rates. Implementation of the guidelines aims at the reduction of VAP to less than 9 episodes per 1000 days of mechanical ventilation. A total of 35 preventive measures were initially selected. A task force of experts used the Grading of Recommendations, Assessment, Development and Evaluation Working Group methodology to generate a list of 7 basic "mandatory" recommendations (education and training in airway management, strict hand hygiene for airway management, cuff pressure control, oral hygiene with chlorhexidine, semi-recumbent positioning, promoting measures that safely avoid or reduce time on ventilator, and discouraging scheduled changes of ventilator circuits, humidifiers and endotracheal tubes) and 3 additional "highly recommended" measures (selective decontamination of the digestive tract, aspiration of subglottic secretions, and a short course of iv antibiotic).

DISCUSSION

We present the Spanish VAP prevention guidelines and describe the methodology used for the selection and implementation of the recommendations and the organizational structure of the project. Compared to conventional guideline documents, the associated safety assurance program, the online data recording and compliance control systems, as well as the existence of a pre-defined objective are the distinct features of "Zero VAP".

Selective ion-induced intermixing and damage in low-dimensional GaN/AlN quantum structures

Ion-induced intermixing and damage is evaluated in GaN/AlN superlattices of quantum dots (QDs) and quantum wells (QWs) using 100 keV Ar(+) implantation at low temperature (15 K). Despite the similar damage build up at low fluences, a significant increase of the damage accumulation takes place for QDs at high fluences. Elemental depth profiles were fitted with a diffusion model, revealing the higher intermixing efficiency in QD superlattices, significantly higher than for QWs. The scaling of diffusion length with the local fluence and defect concentration is understood on the basis of cascade mixing and migration of defects in the cation sublattice. The selective intermixing/damage of QDs is explained by the promotion of lateral diffusion mechanisms that result in smooth interfaces, as well as by an enhanced diffusivity due to the characteristic strain distribution in QD superlattices.

Is there a link between influenza and type I diabetes? Increased incidence of TID during the pandemic H1N1 influenza of 2009 in Chile

Pandemic H1N1 2009 had the highest incidence in the middle-high income area of Santiago and affected mostly school age patients. Influenza A virus (IAVs) causes systemic and most commonly non-systemic infection. Interestingly, it is able to replicate only in the presence of trypsin-like enzymes, as lung and pancreas.

HYPOTHESIS

IAVs infection may trigger beta cell destruction and increase the incidence of T1DM.

METHODS

A retrospective observational study of new T1DM pediatric patients from database of Clinica Las Condes between 1995 and 2012.

RESULTS

From 58 patients, 44.7% were diagnosed between 2009 and 2010, coincident with the H1N1 virus outbreak. There were no differences in clinical neither metabolic parameters between those patients from the 2009-2010 period and the rest. From those patients with available antibody panel, it was negative in 30% of the 2009-2010 group vs. 12.5% of the rest of the cohort (p < 0.05). Only one 5.8 year old boy had history of H1N1 virus infection three months prior to the DM1 onset with negative antibodies.

CONCLUSIONS

The temporal coincidence suggests a possible link between T1DM and H1N1 virus, might be thought to be through direct cytopathic damage. Unfortunately we could only confirm H1N1 previous infection in only one case. Prospective studies in new T1DM cases are necessary to test this hypothesis.

[Outcome at two years corrected age of a cohort of very low birth weight infants from hospitals within the neonatal SEN1500 network]

OBJECTIVE

To describe growth and neurodevelopmental status of 4,944 children who completed a follow-up at two years of corrected age out of the 10,456 newborns with weight ≤1500g born between the years 2002-2007 and discharged from hospitals within the network SEN1500. A total of 522 newborns were excluded as they had some type of malformation. The total number of children assessed represents the 49.76% of children discharged alive and without malformations.

METHODS

A retrospective review was conducted using prospectively collected data in the SEN1500 database. We compared growth data at two years of corrected age according to birth weight and sex. Motor impairment, incidence of cerebral palsy, visual and hearing disabilities, and abnormal neurodevelopment for gestational age were analysed between groups. We studied the associations between cerebral palsy (CP) and perinatal factors.

RESULTS

At 2 years of age 44.2% of children had a weight <2 SD for corrected age. Children with birth weight ≤1000g showed worse outcomes in growth. Some type of motor impairment was observed in 6.96% of the infants, and 4.56% of them were diagnosed with CP. The incidence was higher among males with birth weight ≤1000g. There was an incidence of 5.21% of visual disability, with 0.5% of children being blind in one or both eyes. Cerebral palsy was associated with retinopathy of prematurity, severe intraventricular haemorrhage, and periventricular leukomalacia, in particular cystic periventricular leukomalacia.

Design and characterization of biofunctional magnetic porous silicon flakes

Magnetic porous silicon flakes (MPSF) were obtained from mesoporous silicon layers formed by multi-step anodization and subsequent composite formation with Fe oxide nanoparticles by thermal annealing. The magnetic nanoparticles adhered to the surface and penetrated inside the pores. Their structure evolved as a result of the annealing treatments derived from X-ray diffraction and X-ray absorption analyses. Moreover, by tailoring the magnetic load, the dynamic and hydrodynamic properties of the particles were controlled, as observed by the pressure displayed against a sensor probe. Preliminary functionality experiments were performed using an eye model, seeking potential use of MPSF as reinforcement for restored detached retina. It was observed that optimal flake immobilization is obtained when the MPSF reach values of magnetic saturation >10(-4)Am(2)g(-1). Furthermore, the MPSF were demonstrated to be preliminarily biocompatible in vitro. Moreover, New Zealand rabbit in vivo models demonstrated their short-term histocompatibility and their magnetic functionality as retina pressure actuators.

Real-time RT-PCR detection of betanodavirus in naturally and experimentally infected fish from Spain

Infections with betanodavirus affect a wide range of wild and farmed fish species throughout the world, mostly from the marine environment. The aim of this work was to develop and validate real-time RT-PCR assays for sensitive and specific detection of nodavirus in diseased or carrier fish. The new detection assay was used to study the transmission and development of nodavirus infection in juvenile sea bass, Dicentrarchus labrax (L.), challenged by different routes, and also to screen for nodavirus in various farmed fish species. On average, the sensitivity was 10-100 times higher than a standard RT-PCR, and the assay was able to detect asymptomatic carrier fish that otherwise could have been classified as free of infection. Clinical signs of nodavirus infection were reproduced in fish infected following bath exposure or intramuscular injection, demonstrating horizontal transmission of the disease. Nodavirus was always detected in the brain of diseased fish but also in many recovered fish. The new assay enables us to confirm the presence of the virus at an early phase in the production cycle and may represent a useful tool to prevent or slow down the spread of nodavirus to new locations.

[Inflammatory myxohyaline tumor of the distal extremities]

Inflammatory myxohyaline tumor of the distal extremities is an extremely rare low-grade sarcoma with a tendency to produce local recurrence after surgical excision, but with a low metastatic potential. We present the case of a 49-year-old woman with a slow-growing asymptomatic tumor on the right pretibial region that was initially considered to be a lipoma. Histopathology revealed the presence of a polymorphic inflammatory infiltrate within a myxoid and hyaline matrix. Interspersed between the inflammatory cells were 3 different populations of neoplastic cells: atypical spindle-shaped cells; bizarre epithelioid cells, some of which were multinucleated and resembled the virocytes or Reed-Sternberg cells; and cells with abundant, vacuolated cytoplasm, similar to lipoblasts. These clinical-pathologic findings led to a diagnosis of inflammatory myxohyaline tumor of the distal extremities. Although the tumor was excised with wide surgical margins, local recurrence developed after 3 months and was treated with re-excision and radiotherapy.

Impact of peritonitis on long-term survival of peritoneal dialysis patients

The impact of each episode of peritonitis on long-term survival of peritoneal dialysis (PD) patients has yet to be defined.

OBJECTIVES

To determine the risk that each episode of peritonitis poses for patient survival and for the PD technique.

PATIENTS

1515 patients included in the Levante registry from 1 January 1993 to 31 December 2005.

METHODS

Retrospective analysis of a multicentre registry using Cox regression for time-dependent variables.

RESULTS

We analysed 1609 episodes of peritonitis in 716 patients (47.2%). In the univariate analysis, each case of peritonitis treated in the outpatient unit was associated with an increase in mortality (hazard ratio [HR] 1.99, P<.001), which was greater for episodes that required hospitalisation (HR 3.62, P<.001). Mortality increased with each successive episode in the same patient. Multivariate analysis confirmed the association of each case of peritonitis with lower long-term survival (HR 2.01, P<.001), with a different risk for episodes due to gram-positive and gram-negative bacteria and fungi (HR 1.73, 2.43 and 5.71, respectively; P<.001). Other variables associated with mortality were age, low residual renal function, absence of vascular access and comorbidity. Peritonitis was the only independent variable associated with technique failure (HR 1.29, P<.001), with a different risk for episodes due to gram-positive and gram-negative bacteria and fungi (HR 1.73, 2.43 and 5.71, respectively; P<.001).

CONCLUSIONS

Episodes of peritonitis negatively influence long-term survival of patients on PD.

Nutritive value of herbage from mountain hay meadow managed under traditional and intensive harvest systems as affected by nitrogen fertilisation and time of cutting

The aim of this study was to investigate the influence of harvest season and nitrogen (N) fertilisation on chemical composition and digestibility of the herbage harvested from a mountain meadow (of the vegetation type Arrhenatheretalia). Four rates of N fertiliser (0, 60, 120 and 180 kg N/ha per year in a single spring application of calcium ammonium nitrate) were compared in field-replicated plots. The experiment lasted 7 years. During the first 3 years each plot was harvested twice per year (June and September) according to a traditional harvest system, whereas in the last 3 years (after a transitional year) each plot was harvested three times per year (spring, summer and autumn) following a more intensive harvest system. In both harvest systems, herbage collected in the first cut (early or late June) had higher fibre contents and lower digestibility (P < 0.001) than herbage collected in the regrowth. N fertiliser increased significantly (P < 0.001) the annual yield of herbage in the 2-harvest system, but did not affect (P > 0.10) herbage yield in the 3-cuts system. N fertiliser changed the botanical composition of herbage and promoted grass growth, resulting in increased (P < 0.05) fibre content and decreased (P < 0.05) digestibility and rate of degradation of herbage, these effects being variable in the different harvest seasons. Our results suggest that the more intensive management system without N fertilisation could be considered a suitable practice for the management of these botanically complex mountain meadows. These results may contribute to design fertilisation and management practices of mountain hay meadows to optimise their productivity and sustainability.

Long-chain polyunsaturated fatty acid concentration in patients with inborn errors of metabolism

INTRODUCTION

Long-chain polyunsaturated fatty acid (LCPUFA) can be provided by diet (fatty fish, eggs, viscera and human milk) or synthetised from essential fatty acids linoleic and α-linolenic acids through the microsomal pathway. However, endogenous LCPUFA synthesis is rather low, especially for docosahexaenoic (DHA), and seems insufficient to achieve normal DHA values in individuals devoid of preformed dietary supply. Inborn errors of metabolism (IEMs) are therefore diseases with a special risk for LCPUFA deficient status.

AIM

Our aim was to evaluate LCPUFA status in 132 patients with different IEMs.

METHODS

We performed a cross-sectional study of plasma and erythrocyte LCPUFA composition of 63 patients with IEMs treated with protein-restricted diets compared with data from 69 patients with IEMs on protein-unrestricted diets, and 43 own reference values.

RESULTS

Erythrocyte and plasma DHA and arachidonic acid concentrations were significantly decreased in patients treated with protein-restriction compared with those on protein-unrestricted diets and with our reference values (p < 0.0001). In the protein-restricted group, 45% of patients showed decreased erythrocyte and plasma DHA values (only 7% and 10%, respectively in the protein-unrestricted group) (p < 0.0001). Erythrocyte and plasma DHA values correlated with the natural protein intake in patients on protein-restriction (r = 0.257; p = 0.045; r = 0.313; p = 0.014, respectively).

CONCLUSION

Plasma and erythrocyte DHA concentrations are decreased in patients with IEMs treated with protein restriction. DHA concentration correlates with the patients' protein intake. Supplementation of patients with LCPUFA would have a beneficial influence on their nutritional status.

Size and surface effects in the magnetic properties of maghemite and magnetite coated nanoparticles

An increasing number of promising applications for future technology is arising from size constraints in nanoparticles (NPs) and from the chemical manipulation of their surfaces. In this work, we analyse the finite-size and surface effects on polyacrylic acid-coated Fe(3)O(4) NPs and oleic acid-coated gamma-Fe(2)O(3) NPs by studying their magnetization curves at different temperatures. The measured thermal dependence of the saturation magnetization is no longer explained by the typical T(3/2) Bloch law, yielding higher values than those expected for its exponent. When incorporated in polymeric matrixes to form magnetic transparent nanocomposites, the oleic acid-coated gamma-Fe(2)O(3) NPs also deviate from Bloch's law, but following the opposite trend observed in free coated NPs.

An evaluation of a macroalgal bioassay tool for assessing the spatial extent of nutrient release from offshore fish farms

In this study we develop and evaluate a macroalgal bioassay tool for monitoring the spatial extent of dissolved wastes loaded from offshore fish farms into the marine coastal ecosystem. This tool is based on the analysis of the nitrogen stable isotope ratio (delta(15)N) in tissues of several benthic primary producers (macroalgae and Posidonia oceanica epiphytes) incubated, by means of incubation devices, in the water column at increasing distances (from 0 m to 1000 m) from the fish cages. The bioassays were performed in three fish farms situated in different geographical locations (the Canary Islands, Murcia and Catalonia) and we test: the suitability of the different macroalgae species used in relation with their resistance to incubation and their sensitivity to fish farm wastes and the most appropriate incubation depth (5 m or approximately 20 m) and incubation time (2, 4 or 6 days) to detect the spatial distribution of delta(15)N around fish farms. In general terms, the results showed a significant increment of delta(15)N values toward the fish cages with respect to the reference (initial) and control values for all the species of macroalgae tested except for the red algae Asparagopsis taxiformis from Canary Islands. The magnitude and shape of the reported spatial responses varied as a function of the experimental settings analyzed as well as a function of the nutrient regime characteristics of each coastal area. The spatial gradient was more consistent in the shallow part of the water column (5 m depth), than in the deeper part ( approximately 20 m) and was statistically significant after an incubation period of four days. These results confirm the effectiveness and reliability of the method proposed, enabling the spatial extent of nutrients derived from fish farms to be assessed in an effective and simple manner, suitable for use in monitoring programs around offshore fish farms.

Influence of temperature and predation on survival of Salmonella enterica serovar Typhimurium and expression of invA in soil and manure-amended soil

The effects of three temperatures (5, 15, and 25 degrees C) on the survival of Salmonella enterica serovar Typhimurium in topsoil were investigated in small microcosms by three different techniques: plate counting, invA gene quantification, and invA mRNA quantification. Differences in survival were related to the effect of protozoan predation. Tetracycline-resistant Salmonella serovar Typhimurium was inoculated into soil and manure-amended soil at 1.5 x 10(8) cells g soil(-1). Population densities were determined by plate counting and by molecular methods and monitored for 42 days. Simultaneous extraction of RNA and DNA, followed by quantitative PCR, was used to investigate invA gene levels and expression. Analysis by these three techniques showed that Salmonella serovar Typhimurium survived better at 5 degrees C. Comparing DNA and CFU levels, significantly higher values were determined by DNA-based techniques. invA mRNA levels showed a fast decrease in activity, with no detectable mRNA after an incubation period of less than 4 days in any of the soil scenarios. A negative correlation was found between Salmonella serovar Typhimurium CFU levels and protozoan most probable numbers, and we propose the role of the predator-prey interaction as a factor to explain the die-off of the introduced strain by both culture- and DNA quantification-based methods. The results indicate that temperature, manure, and protozoan predation are important factors influencing the survival of Salmonella serovar Typhimurium in soil.

Phase mapping of aging process in InN nanostructures: oxygen incorporation and the role of the zinc blende phase

Uncapped InN nanostructures undergo a deleterious natural aging process at ambient conditions by oxygen incorporation. The phases involved in this process and their localization is mapped by transmission electron microscopy (TEM)-related techniques. The parent wurtzite InN (InN-w) phase disappears from the surface and gradually forms a highly textured cubic layer that completely wraps up a InN-w nucleus which still remains from the original single-crystalline quantum dots. The good reticular relationships between the different crystals generate low misfit strains and explain the apparent easiness for phase transformations at room temperature and pressure conditions, but also disable the classical methods to identify phases and grains from TEM images. The application of the geometrical phase algorithm in order to form numerical moiré mappings and RGB multilayered image reconstructions allows us to discern among the different phases and grains formed inside these nanostructures. Samples aged for shorter times reveal the presence of metastable InN:O zinc blende (zb) volumes, which act as the intermediate phase between the initial InN-w and the most stable cubic In(2)O(3) end phase. These cubic phases are highly twinned with a proportion of 50:50 between both orientations. We suggest that the existence of the intermediate InN:O-zb phase should be seriously considered to understand the reason for the widely scattered reported fundamental properties of thought to be InN-w, as its bandgap or superconductivity.

[Intraoperative complications of corticosubcortical mapping]

By looking through our cases and literature, an analysis of the surgical complications derived from direct cerebral stimulation under general anesthesia and local anesthesia and sedation was made. A retrospective descriptive study was performed including patients who were intervened in our centre from 2004 to 2008 and had the cortico-subcortical mapping technique. Common pre-operation variables were as follow: Age, sex, tumor localization and tumor's pathology; On patients intervened while awake, we collected the ASA, BMI and duration of the intervention. Afterwards, variable like epileptic attacks and cerebral edema were included in two groups. In addition, on those awake, respiratory and circulatory complications, local anesthesia toxicity, poor level of sedation, nausea and vomiting, pain and feeling uncomfortable with body posture were collected as well. A total of 20 patients had surgery. 10 of them were operated under local anesthesia and sedation with a mean age of 41 years, mean BMI of 26.8 and a pre-operatory ASA score of I or II ( except one patient with ASA III). The mean time duration of the surgical procedure was 5 hours and 20 minutes. On the other side, 10 patients were intervened with general anesthesia with a mean age of 55 years. There were no cases of cerebral edema in either group, although in 4 patients had epileptic attacks which resolved with cold saline irrigation. Five patients with local anesthesia and sedation did not have any complication, 2 patients showed desaturation episodes without further complications, three manifested hypertension episodes and two signs of feeling uncomfortable with body posture. None of the intra-operatory complications registered interfered wit the overall surgical procedure. This is a safe technique if performed following recommended indications and parameters. Regarding complications, respiratory complications are the most common and the most dangerous, as they can influence in the surgical procedure for difficult cases.

Grass pollen, aeroallergens, and clinical symptoms in Ciudad Real, Spain

BACKGROUND

In allergic individuals, onset of symptoms is related to atmospheric pollen grain counts and aeroallergen concentrations. However, this relationship is not always clear.

OBJECTIVES

To analyze the correlation between grass pollen grain and aeroallergen concentrations in Ciudad Real, Spain, during the year 2004 and establish their association with symptoms in patients with allergic asthma, rhinitis, or both.

METHODS

Two different samplers were used to assess allergen exposure: a Burkard spore trap to collect pollen grains and a high-volume air sampler to collect airborne particles. Individual filters were extracted daily in phosphate-buffered serum and analyzed by enzyme-linked immunosorbent assay based on serum containing high titers of specific immunoglobulin (Ig) E to grasses. The study population comprised 27 grass-allergic patients whose symptoms and medication were recorded daily.

RESULTS

Grass pollens were detected between April 28 and July 18. There was a positive correlation between pollen grain counts and symptoms (r = 0.62; P > .001). Grass aeroallergens were detected not only during the grass pollination period, but also before and after this period. There was also a very significant correlation between aeroallergen levels and symptoms (r = 0.76; P < .0001). The threshold level for grass pollen was 35 grains/m3.

CONCLUSIONS

Grass-related allergenic activity is present throughout the year, demonstrating the existence of aeroallergens outside the pollen season. Symptoms in allergic patients may be related to airborne particle concentrations. This fact should be taken into account in the clinical follow-up and management of allergic patients.

[Effect of gastric bypass on the metabolic syndrome and on cardiovascular risk]

BACKGROUND

Obesity is associated with increased morbimortality cardiovascular. Individual with metabolic syndrome (MS) are a high risk of developing cardiovascular disease (CVD). The aim of this study was to determine the prevalence of the MS in morbidly obese patients enrolling in a bariatric surgery program and to evaluate the impact of weigh loss induced by gastric bypass on the MS and on the predicted 10-year cardiovascular risk.

MATERIAL AND METHODS

We studied 46 morbidly obese patients who underwent laparoscopic gastric bypass and were followed for 2 years. MS was defined following the IDF 2005 criteria and the insulin resistance (IR) was calculated by using HOMA index. Risk assessment for estimating 10-year ECV risk was carried out according to Framingham score.

RESULTS

Before surgery, 67.2% of patients had IR and 60,9% met the definition of the MS. 17.3% of patients had an elevated cardiovascular risk category. 2 years after gastric bypass, the percentage of excess body weight lost was 72%. All patients restored their HOMA index and only 1 patient (3.6%) had MS. Resolution of hypertension, disglucemia and dislipemia has been observed in 85%, 93.8% and 95.6% of patients. Estimated cardiovascular risk decreased from 4.5% at baseline to 1% at 2 years after surgery.

CONCLUSIONS

SM is common in morbidly obese patients. Bypass gastric is associated with an improvement or resolution in cardiovascular risk factors and IR and result in a significant reduction in MS prevalence and of predicted 10-year cardiovascular risk.