ABSTRACT
Diabetes Mellitus (DM) affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI) and beat-to-beat systolic blood pressure (SBP) variability of patients during supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control). A statistically significant distinction between control and diabetic subjects was provided by the standard deviation and the higher moments of the distributions (skewness, and kurtosis) with respect to the median. To compare IBI and SBP for different populations, we define a parameter, α, that combines the variability of the heart rate and the blood pressure, as the ratio of the radius of the moments for IBI and the same radius for SBP. As diabetes evolves, α decreases, standard deviation of the IBI detrended signal diminishes (heart rate signal becomes more "rigid"), skewness with respect to the median approaches zero (signal fluctuations gain symmetry), and kurtosis increases (fluctuations concentrate around the median). Diabetes produces not only a rigid heart rate, but also increases symmetry and has leptokurtic distributions. SBP time series exhibit the most variable behavior for recently diagnosed DM with platykurtic distributions. Under controlled breathing, SBP has symmetric distributions for DM patients, while control subjects have non-zero skewness. This may be due to a progressive decrease of parasympathetic and sympathetic activity to the heart and blood vessels as diabetes evolves.
Subject(s)
Blood Pressure/physiology , Diabetes Mellitus, Type 2/physiopathology , Heart Rate/physiology , Adult , Aged , Blood Pressure Determination , Body Mass Index , Case-Control Studies , Female , Humans , Male , Middle Aged , Respiration , Supine Position , Young AdultABSTRACT
BACKGROUND: Endophtalmitis post cataract surgery is one of most feared and devastating complications resulting in serious consequences and an uncertain visual prognosis. Antimicrobial prophylaxis against endophtalmitis must be based on the best knowledge of conjuntival microbiota. OBJECTIVE: To establish microbiological basis for the best antibiotic prophylaxis to prevent endophthalmitis in cataract surgery. MATERIALS AND METHODS: A descriptive, cross-sectional, prospective study. A preoperative conjunctival sample was taken from the lower fornix of 118 pacients, sowing it immediately in culture media. Identification of growing colonies and susceptibility testing were performed by manual or automated methods. RESULTS: 106 (89.8%) of 118 preoperative cultures were positive. 159 bacteria were isolated in single or mixed flora, with 95% of Gram positive organisms. Staphylococci represented 76.1% of isolated bacteria, with 82.6% of coagulase-negative staphylococci (SCN) and 17.4% of Staphylococcus aureus. Forty two percent of SCN and 38% of S. aureus were methicillin resistan; both groups showed high susceptibility to tobramycin and fourth-generation fluoroquinolones. CONCLUSIONS: we recommend the use of topical tobramycin as pre-operative antimicrobial prophylaxis associated with povidone-iodine antisepsis. A fourth-generation quinolone is recommended when there is risk of infection.
Subject(s)
Cataract Extraction , Conjunctiva/microbiology , Endophthalmitis/prevention & control , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , Antibiotic Prophylaxis , Cross-Sectional Studies , Disk Diffusion Antimicrobial Tests , Female , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
Background. Endophtalmitis post cataract surgery is one of most feared and devastating complications resulting in serious consequences and an uncertain visual prognosis. Antimicrobial prophylaxis against endophtalmitis must be based on the best knowledge of conjuntival microbiota. Objective: To establish microbiological basis for the best antibiotic prophylaxis to prevent endophthalmitis in cataract surgery. Materials and Methods: A descriptive, cross-sectional, prospective study. A preoperative conjunctival sample was taken from the lower fornix of 118 pacients, sowing it immediately in culture media. Identification of growing colonies and susceptibility testing were performed by manual or automated methods. Results: 106 (89.8%) of 118 preoperative cultures were positive. 159 bacteria were isolated in single or mixed flora, with 95% of Gram positive organisms. Staphylococci represented 76.1% of isolated bacteria, with 82.6% of coagulase-negative staphylococci (SCN) and 17.4% of Staphylococcus aureus. Forty two percent of SCN and 38% of S. aureus were methicillin resistan; both groups showed high susceptibility to tobramycin and fourth-generation fluoroquinolones. Conclusions: we recommend the use of topical tobramycin as pre-operative antimicrobial prophylaxis associated with povidone-iodine antisepsis. A fourth-generation quinolone is recommended when there is risk of infection.
Introducción: La endoftalmitis post-cirugía de cataratas es una de las complicaciones post-operatorias más temidas y devastadoras, pudiendo ocasionar secuelas graves, con un pronóstico visual incierto. La profilaxis antimicrobiana de esta complicación debe basarse en el conocimiento acabado de la microbiota presente en el territorio conjuntival. Objetivo: Establecer bases microbiológicas para una mejor profilaxis antimicrobiana de la endoftalmitis en cirugía de cataratas. Materiales y Métodos: Estudio descriptivo, de corte transversal, prospectivo. A 118 pacientes se les tomó muestra conjuntival pre-operatoria del fondo de saco inferior, sembrándola de inmediato en medios de cultivo. Las colonias desarrolladas se identificaron por métodos manuales y método de microdilución y difusión en disco. Resultados: De 118 cultivos pre-operatorios, 106 (89,8%) desarrollaron colonias bacterianas. Se aislaron 159 bacterias conjuntivales como especie única o cultivo mixta, siendo 95% grampositivas. El género Staphylococcus representó 76,1% del total de bacterias aisladas, siendo 82,6% Staphylococcus coagulasa negativa (SCN) y 17,4% Staphylococcus aureus. El 42% de los SCN y 38% de S. aureus presentaron resistencia a meticilina, presentando ambos buena susceptibilidad a tobramicina y fluoroquinolonas de cuarta generación. Conclusiones: Considerando nuestros resultados, recomendaríamos a nuestros pacientes tobramicina tópica como antibioprofilaxis, asociada a povidona yodada como antiséptico. Una quinolona de cuarta generación podría usarse cuando existan factores de riesgo de infección.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Cataract Extraction , Conjunctiva/microbiology , Endophthalmitis/prevention & control , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Antibiotic Prophylaxis , Anti-Bacterial Agents/pharmacology , Cross-Sectional Studies , Disk Diffusion Antimicrobial Tests , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Prospective StudiesABSTRACT
Objetivo: avaliar o estágio atual da cirurgia refrativa na América Latina. Material e método: questionário analisando aspectos demográficos de cada país, técnicas realizadas, custo de equipamentos e preços cobrados por serviços säo estudados. Também säo analisadas as sugestöes e críticas ao estado atual da cirurgia refrativa em diferentes regiöes. Os questionários foram respondidos pelos representantes da International Society of Refractive Surgery. A data de término da pesquisa foi de 30/03/97. Resultados: Duas centenas de Excimer Lasers funcionam na América Latina. Os preços dos serviços variam de 200 a 2200 USD com variaçöes regionais. Queixas como comportamento antiético, alto preço dos equipamentos e baixo preço dos serviços se constituem nos ..