1,720,958 research outputs found
Pulmonary hypertension in sickle cell disease children under 10 years of age
No full textBr J Haematol. 2010 Sep;150(5):601-9. Epub 2010 Jun 10.
Pulmonary hypertension in sickle cell disease children under 10 years of age.
Colombatti R, Maschietto N, Varotto E, Grison A, Grazzina N, Meneghello L, Teso S, Carli M, Milanesi O, Sainati L.
Source
Department of Paediatrics, University of Padova, Padova, Italy. [email protected]
Abstract
Despite the finding of elevated Tricuspid Regurgitant Velocity (TRV) in children below 5 years of age, the prevalence and evolution of Pulmonary Hypertension (PH) in young children with sickle cell disease (SCD) are unclear. In order to identify predictive factors of precocious PH development, SCD children > or =3 years old, at steady state, underwent annual echocardiography and Tissue Doppler Imaging (TDI). Patients receiving chronic transfusion were excluded. Thirty-seven of seventy-five patients were > or =3 years, with measurable TRV. In our young population (mean age 6.2 years) of mainly African, HbS/HbS patients, 8/37 (21.6%) had TRV > or =2.5 m/s, 8% being only 3 years old. Significant correlation was found between precocious TRV elevation and high platelet and reticulocyte counts and frequent acute chest syndromes (ACS). In multivariate analysis, ACS was the only variable predicting TRV > or =2.5 m/s. TDI of the 37 patients showed signs of diastolic dysfunction of the left ventricle. At follow-up all eight patients with high TRV displayed further increase and seven more developed TRV > or =2.5 m/s. PH seems to begin in children earlier than expected. Factors involved in its early onset might be different from the ones causing its development in older children or adults. African children might benefit from early screening and re-assessment once a year.
PMID:
20553267
[PubMed - indexed for MEDLIN
A new device (Neonatal Helmet-CPAP) for administration of continuous positive airway pressure in preterm infants: Comparison with a standard nasal-CPAP system
No full textI.F. 2.83
A new device for administration of continuous positive airway pressure in preterm infants: comparison with a standard nasal CPAP continuous positive airway pressure system.
No full textOBJECTIVE:
We compared the effectiveness of a new continuous positive airway pressure (CPAP) device (neonatal helmet CPAP) with a conventional nasal CPAP system in preterm neonates needing continuous distending pressure.
DESIGN AND SETTING:
Randomized, physiological, cross-over study in a tertiary referral, neonatal intensive care unit in a university teaching hospital.
PATIENTS:
Twenty very low birth weight infants with a postnatal age greater than 24 h who were receiving nasal CPAP for apnea and/or mild respiratory distress were enrolled.
INTERVENTIONS:
CPAP delivered by neonatal helmet CPAP and nasal CPAP in random order for two subsequent 90-min periods.
MEASUREMENTS AND RESULTS:
Were continuously measured the Neonatal Infant Pain Scale (NIPS) score, oxygen requirements, respiratory rate, heart rate, oxygen saturation, transcutaneous PO(2) (tcPO(2)) and PCO(2) (tcPCO(2)), blood pressure, and desaturations. NIPS scores were significantly lower when the infants were on the neonatal helmet CPAP than when they were on nasal CPAP (0.26+/-0.07 vs. 0.63+/-0.12). The other studied parameters did not differ between the two CPAP modes. The number of desaturations was reduced during the neonatal helmet CPAP treatment (18 vs. 32), although this difference was not significant.
CONCLUSIONS:
In this short-term physiological study the neonatal helmet CPAP appears to be as good as the golden standard for managing preterm infants needing continuous distending pressure, with enhanced tolerability. Further evaluation in a randomized clinical trial is needed to confirm these findings
Does helmet CPAP reduce cerebral blood flow and volume by comparison with Infant Flow driver CPAP in preterm neonates?
No full textOBJECTIVE:
We compared neonatal helmet continuous positive airway pressure (CPAP) and the conventional nasal Infant Flow driver (IFD) CPAP in the noninvasive assessment of absolute cerebral blood flow (CBF) and relative cerebral blood volume changes (DeltaCBV) by near-infrared spectroscopy.
DESIGN AND SETTING:
A randomized crossover study in a tertiary referral NICU.
PATIENTS AND INTERVENTIONS:
Assessment of CBF and DeltaCBV in 17 very low birth weight infants with respiratory distress (median age 5 days) treated with two CPAP devices at a continuous distending pressure of 4 mbar.
MEASUREMENTS AND RESULTS:
Neonates were studied for two consecutive 60-min periods with helmet CPAP and with IFD CPAP. Basal chromophore traces enabled DeltaCBV changes to be calculated. CBF was calculated in milliliters per 100 grams per minute from the saturation rise integral and rate of rise O(2)Hb-HHb. Median (range) CBF with helmet CPAP was 27.37 (9.47-48.20) vs. IFD CBF 34.74 (13.59-60.10)(p=0.049) and DeltaCBV 0.15 (0.09-0.28) with IFD and 0.13 (0.07-0.27) with helmet CPAP (NS). Using helmet and IFD CPAP, the neonates showed no difference in mean physiological parameters (transcutaneous carbon dioxide and oxygen tension, pulse oximetry saturation, heart rate, breathing rate, mean arterial blood pressure, desaturation rate, axillary temperature).
CONCLUSION:
Assessing CBF and DeltaCBV measured by near-infrared spectroscopy with two CPAP devices revealed no differences in relative blood volume, but CBF was lower with helmet CPAP. Greater active vasoconstriction and/or passive capillary and/or venous vessel compression seem the most likely reason, due to a positive pressure around the head, neck, and shoulders by comparison with the airway pressure
Laryngeal mask airway used as a delivery conduit for the administration of surfactant to preterm infants with respiratory distress syndrome
No full textBackground: The laryngeal mask airway (LMATM, Laryngeal Mask Co. Ltd, Jersey, UK) is a supraglottic device used to administer positive pressure ventilation (PPV) in adults, pediatric and neonatal patients. Objectives: To avoid endotracheal intubation, we evaluated the feasibility and practicality of administering surfactant via the LMATM in preterm infants with respiratory distress syndrome (RDS). Methods: Infants less than 72 h old with a gestational age of ≤ 35 weeks and a birth weight of >800 g, treated with nasal continuous positive airway pressure (CPAP, 5 cm H2O) for RDS were eligible for inclusion in the study if the arterial-to-alveolar oxygen tension ratio (a/APO2) was 60 min. Results: Eight preterm infants, median gestational age 31 (range 28-35) weeks; birth weight 1,700 (880-2,520) g, treated with nasal CPAP for RDS were enrolled. Three hours after surfactant instillation, the mean a/APO2 was significantly increased (0.13 ± 0.04 to 0.34 ± 0.11; p < 0.01) without complications. Conclusions: The LMATM may be a useful and noninvasive conduit for the administration of surfactant therapy. A large randomized comparative clinical trial will be required to confirm the efficacy of this technique. Copyright © 2005 S. Karger AG
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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