Julio Cesar Martins de Oliveira

Efficacy of Antibiotic Prophylaxis Before the Implantation of Pacemakers and Cardioverter-Defibrillators: Results of a Large, Prospective, Randomized, Double-Blinded, Placebo-Controlled Trial

Background—Although routinely administered, definitive evidence for the benefits of prophylactic antibiotics before the implantation of permanent pacemakers and implantable cardioverter-defibrillators from a large double-blinded placebo-controlled trial is lacking. The purpose of this study was to determine whether prophylactic antibiotic administration reduces the incidence of infection related to device implantation. Methods and Results—This double blinded study included 1000 consecutive patients who presented for primary device (Pacemaker and implantable cardioverter-defibrillators) implantation or generator replacement randomized in a 1:1 fashion to prophylactic antibiotics or placebo. Intravenous administration of 1 g of cefazolin (group I) or placebo (group 2) was done immediately before the procedure. Follow-up was performed 10 days, 1, 3, and 6 months after discharge. The primary end point was any evidence of infection at the surgical incision (pulse generator pocket), or systemic infection related to be procedure. The safety committee interrupted the trial after 649 patients were enrolled due to a significant difference in favor of the antibiotic arm (group I: 2 of 314 infected patients—0.63%; group II: 11 of 335 to 3.28%; RR=0.19; P=0.016). The following risk factors were positively correlated with infection by univariate analysis: nonuse of preventive antibiotic (P=0.016); implant procedures (versus generator replacement: P=0.02); presence of postoperative hematoma (P=0.03) and procedure duration (P=0.009). Multivariable analysis identified nonuse of antibiotic (P=0.037) and postoperative hematoma (P=0.023) as independent predictors of infection. Conclusions—Antibiotic prophylaxis significantly reduces infectious complications in patients undergoing implantation of pacemakers or cardioverter-defibrillators.

STATE-SPACE APPROACH FOR THE ANALYSIS OF SOIL WATER CONTENT AND TEMPERATURE IN A SUGARCANE CROP

The state-space approach is used to describe surface soil water content and temperature behaviour, in a field experiment in which sugarcane is submitted to different management practices. The treatments consisted of harvest trash mulching, bare soil, and burned trash, all three in a ratoon crop, after first cane harvest. One transect of 84 points was sampled, meter by meter, covering all treatments and borders. The state-space approach is described in detail and the results show that soil water contents measured along the transect could successfully be estimated from water content and temperature observations made at the first neighbour.

Field spatial and temporal patterns of soil water content and bulk density changes

Umidade (q) e densidade do solo (rs) influenciam importantes processos no solo e planta tais como: movimento de agua, compactacao do solo, aeracao do solo e desenvolvimento radicular. Baseado neste fato, questoes referentes a variabilidade espacial e temporal de q e rs para diferentes periodos do ano e diferentes fases de desenvolvimento da cultura do cafe tornam-se de extremo interesse. Este trabalho teve como objetivo caracterizar padroes espaciais e temporais de q e rs durante diferentes periodos do ano e verificar se existem mudancas temporais significativas de rs na superficie do solo quando submetida a ciclos de umedecimento/secagem. O experimento foi conduzido em campo cultivado com cafe em um solo classificado como Nitossolo Vermelho Eutrofico. O experimento iniciou-se em maio de 2001 com espacamento de 1,75 m entre linhas e 0,75 m entre plantas. Medidas de q e rs foram feitas metro a metro ao longo de 200 m usando uma sonda de superficie neutron/gama. Durante o periodo umido nao houve padroes de diferenca espacial para q, enquanto que para o periodo seco o contrario foi observado. Estes padroes podem ser associados a eventos de precipitacao alterando a estrutura de correlacao espacial para observacoes adjacentes de q. Para rs existem mudancas temporais na superficie do solo ao longo do periodo estudado como uma consequencia dos ciclos de umedecimento/secagem no campo.

Nitrogen dynamics in a soil-sugar cane system

Results of an organic matter management experiment of a sugar cane crop are reported for the first cropping year. Sugar cane was planted in October 1997, and labeled with a 15N fertilizer pulse to study the fate of organic matter in the soil-plant system. A nitrogen balance is presented, partitioning the system in plant components (stalk, tip and straw), soil components (five soil organic matter fractions) and evaluating leaching losses. The 15N label permitted to determine, at the end of the growing season, amounts of nitrogen derived from the fertilizer, present in the above mentioned compartments.

Incorrect Application Technique of Metered Dose Inhalers by Internal Medicine Residents : Impact of Exposure to a Practical Situation

We evaluated residents regarding maintenance treatment of asthma and the technique for using metered dose inhalers. Methods. Residents were asked to prescribe a treatment for a patient with poorly controlled persistent asthma and to demonstrate the use of metered dose inhaler (MDI) medication. Results. 76% of 239 residents correctly identified the medication indicated for the case; only 30% of them adequately performed the inhalation technique (49% from HCFMUSP vs. 19% from other institutions; p < 0.001). Conclusions. The results demonstrate that, when seeing a typical patient with uncontrolled persistent asthma, most residents are able to correctly identify the drugs indicated for treatment but not adequately instruct the MDI technique use.

Ventricular remodeling in right ventricular apical pacing.

OBJECTIVE To determine ventricular remodeling (VR) and the role of clinical and functional variables in patients with normal cardiac function who underwent right ventricular apical pacing (RVAP). METHODS Among the 268 consecutive patients with standard pacemaker due to complete atrioventricular block (CAVB), those with left ventricular ejection fraction (LVEF) < 55% and left ventricular end-diastolic diameter (LVEDD) > 53 mm on Doppler echocardiography were excluded. Ventricular remodeling was defined as echocardiographic changes documented at least six months after implantation, namely, a >10% increase in LVEDD and a > 20% decrease in LVEF. The following variables were analyzed: underlying heart disease, NYHA functional class of heart failure (HF), time of ventricular stimulation, and QRS duration. Statistical analysis included likelihood ratio test, Fishers exact test, and Wilcoxon rank-sum test. A p value < 0.05 was considered statistically significant. RESULTS The study included 75 patients, mean age 70.9 +/- 14, of whom 22.6% were male. Mean time between both evaluations was 80.2 months. Before implantation, mean LVEF was 72% and LVEDD was 46 mm; after implantation this values were 69.7% (p = 0.0025) and 48.5 mm (p = 0.0001), respectively. Mean QRS duration after implantation was 156 ms. Ventricular remodeling was observed only in four patients (5.3%), and no exploratory variable specified this behavior. CONCLUSION In a long-term follow-up, patients without ventricular dysfunction who underwent RV apical pacing (RVAP) showed low VR rate, and no analyzed variable was associated with its occurrence.

Soil spatial variability and the estimation of the irrigation water depth

A influencia da variabilidade espacial da umidade do solo em uma situacao pre-irrigacao e da capacidade de campo e avaliada no calculo da lâmina de irrigacao. O experimento constou de cultura de feijao (Phaseolus vulgaris L.) estabelecida em um ARGISSOLO da regiao de Piracicaba, SP, irrigada por pivo central, tendo as medidas de umidade sido feitas com sonda de neutrons, em uma malha de 20x4 pontos, espacados de 0.5 m. Em determinada situacao, os 80 valores de lâmina de irrigacao calculados apresentaram um coeficiente de variacao de 29.3%, para uma media de 18 mm, com valor minimo de 9 mm e maximo de 41mm. E concluido que a unica forma pratica de irrigacao e o uso de uma lâmina media devido a variabilidade inerente ao solo, e que a procura de melhores valores para a capacidade de campo nao implica em melhores estimativas da lâmina de irrigacao.

Response to the Letter Regarding Article “Efficacy of Antibiotic Prophylaxis Before the Implantation of Pacemakers and Cardioverter-Defibrillators”

We agree with Khan et al that Clostridium difficile –associated diarrhea (CDAD) is a major concern when using antibiotics. The choice of a single dose of cefazolin before the implantation of a pacemaker or cardioverter-defibrillator was done so for practical purposes.1 It is commonly used as the prophylactic antibiotic of choice before device implantation in many institutions throughout the world. We thought that it was important to perform a trial that reflected the current standard of care for the study to be applicable for clinicians. Of note, flucloxacillin was …

Soil hydraulic conductivily measurement on a sloping field

A field methodology is presented for the measurement of the soil hydraulic conductivity in a sloping field, minimizing the leveling soil movement before water pounding and redistribution. The assurance of vertical flow only is performed through soil water potential isolines. The hydraulic conductivity was determined by the instantaneous profile method. Results for the nine neutron probe access tubes indicate that one single K(q) relation is sufficient to represent the experimental site.E apresentada, aqui, uma metodologia de campo para a determinacao da condutividade hidraulica de um solo em declive, minimizando o corte de terra para posterior inundacao e redistribuicao da agua. A garantia da ocorrencia de fluxo de agua apenas na vertical, e feita atraves de isolinhas de potencial da agua. A condutividade hidraulica foi determinada pelo metodo do perfil instantâneo e os resultados para os nove tubos de acesso de sonda de neutrons indicaram que uma unica relacao K(q) e suficiente para representar a parcela.

Determinação da condutividade hidráulica em área com declive

A field methodology is presented for the measurement of the soil hydraulic conductivity in a sloping field, minimizing the leveling soil movement before water pounding and redistribution. The assurance of vertical flow only is performed through soil water potential isolines. The hydraulic conductivity was determined by the instantaneous profile method. Results for the nine neutron probe access tubes indicate that one single K(q) relation is sufficient to represent the experimental site.E apresentada, aqui, uma metodologia de campo para a determinacao da condutividade hidraulica de um solo em declive, minimizando o corte de terra para posterior inundacao e redistribuicao da agua. A garantia da ocorrencia de fluxo de agua apenas na vertical, e feita atraves de isolinhas de potencial da agua. A condutividade hidraulica foi determinada pelo metodo do perfil instantâneo e os resultados para os nove tubos de acesso de sonda de neutrons indicaram que uma unica relacao K(q) e suficiente para representar a parcela.