Clinical assessment of the effect of digital filtering on the detection of ventricular late potentials

Ventricular late potentials are low-amplitude signals originating from damaged myocardium and detected on the body surface by ECG filtering and averaging. Digital filters present in commercial equipment may interfere with the ability of arrhythmia stratification. We compared 40-Hz BiSpec (BI) and classical 40- to 250-Hz band-pass Butterworth bidirectional (BD) filters in terms of impact on time domain variables and diagnostic properties. In a transverse retrospective age-adjusted case-control study, 221 subjects with sinus rhythm without bundle branch block were divided into three groups after signal-averaged ECG acquisition: GI (N = 40), clinically normal controls, GII (N = 158), subjects with coronary heart disease without sustained monomorphic ventricular tachycardia (SMVT), and GIII (N = 23), subjects with heart disease and documented SMVT. Conventional variables analyzed from vector magnitude data after averaging to 0.3 µV final noise were obtained by application of each filter to the averaged signal, and evaluated in pairs by numerical comparison and by diagnostic agreement assessment, using conventional and optimized thresholds of normality. Significant differences were found between BI and BD variables in all groups, with diagnostic results showing significant disagreement between both filters [kappa value of 0.61 (P<0.05) for GII and 0.31 for GIII (P = NS)]. Sensitivity for SMVT was lower with BI than with BD (65.2 vs 91.3%, respectively, P<0.05). Filters provided significantly different numerical and diagnostic results and the BI filter showed only limited clinical application to risk stratification of ventricular arrhythmia

Desenvolvimento de software para interpretação de dados gasométricos aplicável em unidades de terapia intensiva Software development for gasometric data interpretation applicable in intensive care units

O objetivo deste estudo foi desenvolver um software para interpretação de dados gasométricos aplicável em UTIs. Trata-se de estudo de caráter experimental, sendo selecionada uma base teórica em Java com a IDE NetBeans 6.8 por meio de parceria com profissionais capacitados em Sistemas de Informação. O desenvolvimento do programa foi baseado na criação de um algoritmo, uma sequência de instruções bem definidas e não ambíguas a serem executadas mecanicamente com a finalidade de fornecer um diagnóstico desejado. Foi criado um software aplicável em UTIs denominado InterGas, que é um programa de fácil instalação, possui interface de fácil compreensão e utilização, além de processar os dados rapidamente e de forma precisa, oferecendo como resultado final o diagnóstico para o distúrbio do equilíbrio ácido-básico. O desconhecimento de outra ferramenta que reúna todos os componentes do InterGas o torna um software pioneiro que facilita a tomada de decisão à medida que caracteriza a ocorrência de distúrbios mistos utilizando fórmulas de compensação. Com isso, futuros estudos deverão ser feitos com o objetivo de avaliar aspectos relacionados à implementação e eficácia do software desenvolvido.<br>The objective of this study was to develop a software for data interpretation of gasometric applicable in Intensive Care Units that can provide a diagnosis for disorders of acid-base balance. This is an experimental study being selected on a theoretical basis with the Java IDE NetBeans 6.8 through a partnership with professionals trained in Information Systems. The program development was based on creating an algorithm, a sequence of well-defined and unambiguous to be performed mechanically in order to provide a desired diagnosis. We created a software applicable in intensive care units called InterGas, which is a program easy to install, has an interface easy to understand and use, and to process the data quickly and accurately providing as the final diagnosis for the disorder the acid-base balance. The lack of another tool that brings together all the components of InterGas makes it a pioneering software that facilitates decision-making, as it characterizes the occurrence of mixed disturbances using compensation formulas

HIV-related risky practices among Brazilian young men, 2007

Behavioral surveillance surveys have been carried among military conscripts, in Brazil, since 1996. This paper presents the results of the 2007 survey and compares actual findings with those obtained in previous studies carried out in the period 1999-2002. The conscripts were selected with a two stage sampling stratified by geographical region. The study included a self-reported questionnaire and blood collection for HIV and syphilis testing. Data from 35,432 conscripts aged 17-20 years old were analyzed. The findings show a reduction in regular condom use, with fixed and casual partners, mainly among those with poor educational level. The proportion of conscripts that have sex with other men was maintained (3.2%), but the index of risky sexual behavioral showed worsening results in this group. Also, the HIV prevalence rate increased from 9 to 11.3 per 10,000 in 2007, though the increase was not statistically significant. In conclusion, the evidences found in this paper indicate the need of reformulate policy among young adults