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INTRODUCTION: Intraoperative hypotension (IH) is an independent predictor of mortality. Some experts have suggested that ultrasound measurement of the inferior vena cava (IVC) in spontaneous ventilation can predict IH. OBJECTIVE: To evaluate the capacity of ultrasound measures of IVC in spontaneous ventilation to predict episodes of IH after anaesthesia induction. PATIENTS AND METHODS: We studied 55 high-risk cardiac patients undergoing vascular surgery. The maximum (dIVCmax) and minimum (dIVCmin) diameter of the IVC were measured and the collapsibility index CI = (dIVCmax-dIVCmin)/dIVCmax was calculated prior to anaesthesia induction. Three definitions of IH were used: systolic blood pressure (SBP) less than 100 mmHg, mean arterial pressure (MAP) less than 60 mmHg, and a decrease in MAP greater than or equal to 30% compared to baseline. RESULTS: There were no significant differences in dIVCmax or in CI between patients presenting IH after anaesthesia induction and those who did not. ROC curves for dIVCmax showed an area under the curve of 0.55 (0.39-0.70), 0.69 (0.48-0.90), and 0.57 (0.42-0.73) and ROC curves for the CI were 0.62 (0.47-0.78), 0.60 (0.41-0.78) and 0.62 (0.47-0.78) for the 3 definitions of IH (<100 mmHg, MAP < 60 mmHg, and MAP ≥30% baseline), respectively. CONCLUSIONS: Ultrasound measurements of IVC in spontaneous ventilation are not good predictors of IH after anaesthesia induction in these patients. The optimal cut-off points show low specificity and moderate sensitivity for predicting IH.

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We report an unusual case of an amelanotic melanoma in a 7 year old hispanic child with subclinical globe perforation. Uveal melanoma rarely occurs in children. Young affected patients are mostly light-colored eye Caucasian adolescents. Since they are not common, these tumors are usually not recognized and misdiagnosed. Differential diagnoses and therapeutic options are outlined.

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Introducción: La tendencia actual es diferir la cirugía de revascularización de miembros inferiores hasta etapas avanzadas, lo que explica que sean pacientes de mayor complejidad con alta morbimortalidad cardíaca y respiratoria. Los mayores avances para reducirlas, se han desarrollado en la preparación de los pacientes y en las técnicas quirúrgicas. La elección de la técnica anestésica no ha sido considerada un factor determinante. Los bloqueos regionales presentan potenciales ventajas, como mayor estabilidad hemodinámica y respiratoria. Objetivo: Realizar una revisión bibliográfica y presentación de casos clínicos sobre la utilidad de los bloqueos periféricos para anestesia en la cirugía de revascularización de miembros inferiores. Material y métodos: La búsqueda se realizó a través de la base de datos Medline, LILACS y SciELO. Se incluyeron estudios donde los bloqueos periféricos se utilizaron para anestesia. Se describen dos casos clínicos. Resultados: Se seleccionaron 4 artículos originales, 3 de ellos eran estudios descriptivos de la técnica y el cuarto una comparación con anestesia general inhalatoria. 2más correspondieron a casos clínicos. Conclusiones: No existe evidencia suficiente que permita concluir que reducen la mortalidad o la morbilidad cuando se la compara con las demás técnicas anestésicas. Esto puede ser debido al diseño metodológico de los estudios, a la no utilización de la ecografía como guía y la no sistematización de los bloqueos. El análisis de los casos clínicos sugiere que en situaciones específicas como pacientes de alto riesgo cardíaco y respiratorio, bajo tratamiento con anticoagulantes y antiagregantes estos presentan ventajas sobre las otras técnicas.

Background: The current trend is to defer revascularization surgery from lower limbs to advanced stages, which explains why they are more complex patients with high cardiac and respiratory mortality. The choice of anesthetic technique remains controversial. Regional blockades have potential advantages, such as hemodynamic and respiratory stability. Our primary objective was a bibliographic review to assess the peripheral blockages for anesthesia in lower limb revascularization surgery. Our secondary objective was report two clinical cases. Material and methods: The search was performed through the Medline, LILACS and SciELO database. We included studies where peripheral blocks were used for anesthesia. Two clinical cases are described. Results: Four original articles were selected, 3 of which were descriptive studies of the technique and the fourth a comparison with general inhalation anesthesia. 2 more corresponded to clinical cases. Conclusions: There is insufficient evidence to conclude that peripheral nerve block reduce mortality or morbidity when compared with other anesthetic techniques. This may be due to the methodological design of the studies, to the non-use of echocardiography as a guide and the non-systematization of the blocks. The analysis of the clinical cases suggests that this technique is a good option in specific situations as patients with high cardiac and respiratory risk, under treatment with anticoagulants and antiplatelets drugs.

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OBJECTIVE: To evaluate microcirculation in intermediate and high mortality risk patients undergoing cardiac surgery (CS) with cardiopulmonary bypass (CPB). PATIENTS AND METHODS: The study included 22 patients with a Euroscore >3. Using the Videomicroscopy Side Stream Dark Field system, and evaluation was made of, capillary density, proportion of perfused capillaries, density of perfused capillaries, microcirculatory flow index (MFI), and heterogeneity flow index. Three to five video sequences were recorded: after induction of anaesthesia (T1), at the beginning of the CPB (T2), before finalising CPB (T3), at the end of the surgery, and before the patient was transferred to Intensive Care Unit (T4). Mean arterial pressure decreased, while the blood lactate increased significantly, when comparing the initial and final values (P<.05). MFI increased significantly in T3 and T4 (P<.05) with regards to the initial values. When the patients with and without postoperative complications were compared, significant differences were found in, Euroscore, left ventricular ejection fraction, and MFI in T3. CONCLUSIONS: in patients with intermediate/high preoperative risk, CS and CBP can involve an increase in MFI and blood lactate at the end of the study. These alterations suggest the possibility of a functional microcirculatory shunt at tissue perfusion level, secondary to the surgical injury and the CPB. Further investigation is needed to have a better understanding of the mechanisms involved.

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OBJECTIVE: To evaluate the changes over time (trend) in sign and magnitude for SSVO2 and SVO2 during and after cardiac surgery. PATIENTS AND METHODS: A prospective and observational study was conducted on 34 cardiac surgery patients. Venous blood samples were taken simultaneously from the introductor (SVCO2) and distal (SVO2) port of the pulmonary artery catheter at predefined intervals. Systemic and pulmonary hemodynamic variables were measured at the same time. The trend was calculated as the difference between 2 consecutive measurements (tSO2). Data were processed with ANOVA for multiple comparisons, Pearson correlation coefficient and Bland-Altman analysis. RESULTS: There was a significant correlation between SVCO2 and tSVO2 (R(2)=0.55), the mean of the differences was 0.36±7.75%, and the limits of agreement ranged from -15.1 to 15.9%. The sign of the trend was similar in 85.1% of the paired data. However, the magnitude of the changes in tSVCO2 and tSVO2 were not always equivalent. Between 0 and 5% of the change in the tSVCO2 was coincident with only 44.7% of the tSVO2. A wide variation was found between both trends when the signs and magnitudes of the changes were taken into account. CONCLUSIONS: When considering the sign and magnitude, the change over time of central venous O2 saturations were not interchangeable in cardiac surgery patients. Clinical decisions based exclusively on tSVCO2 monitoring should be taken with caution.

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Este trabalho teve como objetivo investigar a composição química, estabelecer a dose letal média (DL50) e avaliar os potenciais efeitos mutagênicos do extrato hidroalcoólico de folhas e inflorescências de Erythrina mulungu Mart. ex Benth por meio do teste de micronúcleo em medula óssea de camundongos. Os ensaios fitoquímicos foram realizados através de reações preliminares com mudança de coloração e/ou formação de precipitado; a DL50, por meio da administração intraperitoneal de três concentrações dos extratos, avaliando-se o número de óbitos após 48 horas e o teste de micronúcleo foi feito por meio do método do esfregaço, após exposição dos animais a cinco dias de tratamento. Os resultados fitoquímicos demonstraram presença de açúcares redutores, fenóis e taninos, proteínas e aminoácidos, flavonóides, alcalóides, depsídeos e depsidonas e derivados de cumarina em ambos os órgãos; saponinas espumídicas e esteróides e triterpenóides nas folhas e glicosídeos cardiotônicos e antraquinônicos e alcalóides nas inflorescências. Para a DL50 a folha demonstrou-se atóxica e a inflorescência moderadamente tóxica. Para o teste de micronúcleo, os resultados indicaram ausência de citotoxicidade e genotoxicidade dose-dependente para as folhas e independente da dose para as inflorescências. Assim, esses resultados sugerem que a planta, nas condições analisadas, possui potencial para induzir danos ao DNA.

This study aimed to investigate the chemical composition, to establish the mean lethal dose (LD50) and to assess the potential mutagenic effects of hydroalcoholic extract of leaves and inflorescences of Erythrina mulungu Mart. ex Benth by using micronucleus test in bone marrow of mice. Phytochemical assays were carried out through preliminary reactions with color change and/or precipitate formation; the LD50 was obtained by intraperitoneal administration of three concentrations of the extracts, assessing the number of deaths after 48 hours, and the micronucleus test was done by the smear method, after exposure of animals to five days of treatment. Phytochemical results showed the presence of reducing sugars, phenols and tannins, proteins and amino acids, flavonoids, alkaloids, depsides, depsidones and coumarin derivatives in both organs; foaming and steroidal saponins and triterpenes in the leaves and cardiotonic and anthraquinonic glycosides and alkaloids in the inflorescences. Considering the LD50, the leaf was atoxic and the inflorescence was moderately toxic. As regards the micronucleus test, results indicated absence of cytotoxicity while genotoxicity was dose-dependent for leaves and dose-independent for inflorescences. Thus, these results suggest that the plant, under the tested conditions, has the potential to induce damages to the DNA.

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BACKGROUND: The coronary sinus oxygen saturation (SO2) can affect the oxygen saturation of the superior vena cava (superior cava SO2) and the pulmonary artery (pulmonary artery SO2), causing a gradient between the latter two (ΔSO2), as has been observed in different physiological and pathological conditions. The objective of the study was to evaluate the different determinants of ΔSO2 in cardiac surgery patients. METHODS: An observational, prospective study was carried out on 18 patients undergoing elective cardiac surgery. Blood samples were obtained from the superior vena cava, the pulmonary artery, the inferior vena cava, and the coronary sinus before extracorporeal circulation. RESULTS: The following measurements were made: superior cava SO2, pulmonary artery SO2, coronary sinus SO2, and inferior cava SO2. The mean values (± SD) were as follows: superior cava SO2=76.4±12.6%; inferior cava SO2=72.7±15.8%; coronary sinus SO2=46.6±17.0%; and pulmonary artery SO2=71.9±12.9%. The ΔSO2 was 4.5±5.5%. The average oxygen saturation (SO2avg=[Superior cava SO2 + inferior cava SO2]/2) was 74.6±13.7%. The superior cava SO2 was significantly higher than the pulmonary artery SO2, and the ΔSO2 was significantly different from zero (P≤0.05). No significant differences were found between the superior cava SO2 and the inferior cava SO2, and both were significantly different from the coronary sinus SO2. The difference between SO2avg and the pulmonary artery SO2 was 2.74±4.4%. CONCLUSION: The observed ΔSO2 could only be explained by dilution of the superior cava SO2 with blood with a lower SO2. The coronary sinus blood contributed to generate this gradient.

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Aging and gender are factors that affect the variation of physical work capacity. The present paper highlights the importance of the metabolism used by ergonomics to establish the appropriate limits of loads at work. This study compares the aerobic capacity of people from 20 to 71 years old split in 5 different groups. The laboratory experiment tested 33 volunteers (19 women and 14 men). A submaximal step test was used to measure the VO(2) using a portable breath by breath metabolic system and a telemetric heart rate monitor. Three methods to estimate the VO(2max) were compared: 1) a direct measurement of VO(2), 2) estimation by heart rate, and 3) a step test method using predetermined charts. Significant difference was encountered among the estimation methods as well as among the age ranges (F(2,92)=6.43, p<0.05 y F(4,92)=7.18, p<0.05 respectively). The method of direct measurement and the method of predetermined charts were different for the estimation of the VO(2max) with a confidence level of 95%. The method of predetermined charts is better adapted for males and people younger than 30 years. The estimation through non invasive heart rate apparatus was a good appraiser of the maximal oxygen consumption considering both genders and all the age groups.

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We report a systematic collection of Triatominae inside houses and in the peridomestic environment of Alto Beni, department of La Paz, Bolivia. This area is free of Triatoma infestans and although we detected previously seropositivity for Trypanosoma cruzi, the Alto Beni region is not officially considered as endemic for Chagas disease. From 11 houses of five localities, we collected adults, nymphs and eggs of a Rhodnius species, which was confirmed by morphological and morphometric analysis as Rhodnius stali. This little-known species has long been confused with R. pictipes, and was originally described from museum specimens labelled as R. pictipes. Our data show that R. stali is able to establish colonies in domestic and peridomestic habitats in Bolivia, and it is probably the vector responsible for Chagas disease seropositivity observed in the indigenous population of Alto Beni.

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Toro Toro (T) and Yungas (Y) have been described as genetically well differentiated populations of the Lutzomyia longipalpis (Lutz & Neiva, 1912) complex in Bolivia. Here we use geometric morphometrics to compare samples from these populations and new populations (Bolivia and Nicaragua), representing distant geographical origins, qualitative morphological variation ("one-spot" or "two-spots" phenotypes), ecologically distinct traits (peridomestic and silvatic populations), and possibly different epidemiological roles (transmitting or nor transmitting Leishmania chagasi). The Nicaragua (N) (Somotillo) sample was "one-spot" phenotype and a possible peridomestic vector. The Bolivian sample of the Y was also "one-spot" phenotype and a demonstrated peridomestic vector of visceral leishmaniasis (VL). The three remaining samples were silvatic, "two-spots" phenotypes. Two of them (Uyuni and T) were collected in the highlands of Bolivian where VL never has been reported. The last one (Robore, R) came from the lowlands of Bolivia, where human cases of VL are sporadically reported. The decomposition of metric variation into size and shape by geometric morphometric techniques suggests the existence of two groups (N/Y/R, and U/T). Several arguments indicate that such subdivision of Lu. longipalpis could correspond to different evolutionary units

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This is the first report of adult and nymphs (20 nymphs of all stages and 4 adults) of Microtriatoma trinidadensis (Lent 1951) (Hemiptera: Reduviidae: Triatominae) collected in peridomestic environment, in the department of La Paz, Bolivia. These specimens were associated to Rhodnius stali Lent, Jurberg & Galvão 1993. The exceptional finding of M. trinidadensis in peridomestic environment, illustrates the general tendency of triatominae to adapt to human dwellings and dependences.

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This is the first report of adult and nymphs (20 nymphs of all stages and 4 adults) of Microtriatoma trinidadensis (Lent 1951) (Hemiptera: Reduviidae: Triatominae) collected in peridomestic environment, in the department of La Paz, Bolivia. These specimens were associated to Rhodnius stali Lent, Jurberg & Galväo 1993. The exceptional finding of M. trinidadensis in peridomestic environment, illustrates the general tendency of triatominae to adapt to human dwellings and dependences

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Toro Toro (T) and Yungas (Y) have been described as genetically well differentiated populations of the Lutzomyia longipalpis (Lutz & Neiva, 1912) complex in Bolivia. Here we use geometric morphometrics to compare samples from these populations and new populations (Bolivia and Nicaragua), representing distant geographical origins, qualitative morphological variation ("one-spot" or "two-spots" phenotypes), ecologically distinct traits (peridomestic and silvatic populations), and possibly different epidemiological roles (transmitting or nor transmitting Leishmania chagasi). The Nicaragua (N) (Somotillo) sample was "one-spot" phenotype and a possible peridomestic vector. The Bolivian sample of the Y was also "one-spot" phenotype and a demonstrated peridomestic vector of visceral leishmaniasis (VL). The three remaining samples were silvatic, "two-spots" phenotypes. Two of them (Uyuni and T) were collected in the highlands of Bolivian where VL never has been reported. The last one (Robore, R) came from the lowlands of Bolivia, where human cases of VL are sporadically reported. The decomposition of metric variation into size and shape by geometric morphometric techniques suggests the existence of two groups (N/Y/R, and U/T). Several arguments indicate that such subdivision of Lu. longipalpis could correspond to different evolutionary units.

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It is generally accepted that halothane reduces airway and tissue resistance in lungs with preexisting airway tone. However, under conditions of resting airway tone, pulmonary resistance remains unaltered. In this study, we have determined the effects of halothane on respiratory system, pulmonary and chest wall resistive, elastic and viscoelastic mechanical properties, and related the results to findings from lung histology in intact normal rats. Sixteen adult male Wistar rats were allocated randomly to one of two groups (n = 8 in each group): control or halothane group. In the control group, animals were sedated with diazepam 5 mg i.p. and anaesthetized with pentobarbital 20 mg kg-1 i.p. In the halothane group, the anaesthetic was administered at an end-tidal concentration of I MAC throughout the study. Rats were paralysed and underwent mechanical ventilation. Halothane decreased airway resistance but increased the tissue component of resistance (caused by viscoelastic elements and lung inhomogeneity). Static and dynamic elastance also increased with halothane anaesthesia. Pulmonary resistance remained unchanged. Lung histopathology demonstrated airway dilatation and a greater degree of lung collapse and hyperinflation in the halothane group. We conclude that halothane anaesthesia acts both on airway and lung tissue. In airway tissue, dilatation occurs but the lung periphery stiffens. Consequently, these opposing effects result in no overall apparent change in mechanical properties, although changes are observed during halothane anaesthesia in normal animal and subjects.

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La hipertensión arterial afecta la función y la estructura cardiovascular, con hipertrofia y disfunción ventricular frecuentes, en especial en pacientes con cardiopatía isquémica asociada. Evaluamos 20 pacientes entre 40 y 70 años de edad, con diagnóstico de hipertensión esencial (presión arterial diastólica entre 95 y 115 mmHg) asociada a disfunción ventricular (fracción de eyección ó 45 por ciento). Se estudiaron por angiografía radioisotópica la función sistólica, la función diastólica y la circulación periférica en las siguientes etapas: A) al final del período lavado-placebo (pretratamiento); B) en fase aguda, a las 6 horas de amlodipina (10 mg) por vía oral; C) en fase crónica, al final de 8 semanas de igual tratamiento con monodosis. El tratamiento en fase aguda y crónica mostró una disminución significativa de la presión arterial sistólica, diastólica y de la resistencia periférica total (en un 15 por ciento, 14 por ciento y 20 por ciento respectivamente). El pico de llenado del ventrículo izquierdo basal fue 1,9 ñ 0,4 (VFD/S), mejorando un 21 por ciento en el tratamiento crónico en reposo y 17 por ciento durante el ejercicio ergométrico, lo que evidenció una mejoría de la función diastólica del ventrículo izquierdo (p<0,01). El volumen de fin de sístole o residual, aumentado como expresión de la falla de bomba, disminuyó en 15 y 19 por ciento en reposo y esfuerzo. En el pretratamiento los parámetros hemodinámicos muestran disfunción ventricular sistólica y diastólica del ventrículo izquierdo con compromiso del ventrículo derecho, tanto en reposo como en esfuerzo, con disminución de la reserva cardíaca. El efecto vasodilatador de la amlodipina, con disminución de la poscarga, produjo efectos hemodinámicos favorables, tanto en el control de la hipertensión arterial como en la mejoría de la disfunción biventricular asociada (AU)

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La hipertensión arterial afecta la función y la estructura cardiovascular, con hipertrofia y disfunción ventricular frecuentes, en especial en pacientes con cardiopatía isquémica asociada. Evaluamos 20 pacientes entre 40 y 70 años de edad, con diagnóstico de hipertensión esencial (presión arterial diastólica entre 95 y 115 mmHg) asociada a disfunción ventricular (fracción de eyección ó 45 por ciento). Se estudiaron por angiografía radioisotópica la función sistólica, la función diastólica y la circulación periférica en las siguientes etapas: A) al final del período lavado-placebo (pretratamiento); B) en fase aguda, a las 6 horas de amlodipina (10 mg) por vía oral; C) en fase crónica, al final de 8 semanas de igual tratamiento con monodosis. El tratamiento en fase aguda y crónica mostró una disminución significativa de la presión arterial sistólica, diastólica y de la resistencia periférica total (en un 15 por ciento, 14 por ciento y 20 por ciento respectivamente). El pico de llenado del ventrículo izquierdo basal fue 1,9 ñ 0,4 (VFD/S), mejorando un 21 por ciento en el tratamiento crónico en reposo y 17 por ciento durante el ejercicio ergométrico, lo que evidenció una mejoría de la función diastólica del ventrículo izquierdo (p<0,01). El volumen de fin de sístole o residual, aumentado como expresión de la falla de bomba, disminuyó en 15 y 19 por ciento en reposo y esfuerzo. En el pretratamiento los parámetros hemodinámicos muestran disfunción ventricular sistólica y diastólica del ventrículo izquierdo con compromiso del ventrículo derecho, tanto en reposo como en esfuerzo, con disminución de la reserva cardíaca. El efecto vasodilatador de la amlodipina, con disminución de la poscarga, produjo efectos hemodinámicos favorables, tanto en el control de la hipertensión arterial como en la mejoría de la disfunción biventricular asociada

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With the objective of finding reliable, valid, and economic diagnostic tests to identify Chlamydia trachomatis in conjunctival smears, the sensitivity, specificity, and positive and negative predictive values of Lendrum and Giemsa stains were evaluated using direct immunofluorescence as the gold standard. In addition, inter- and intraobserver reproducibility were estimated through the use of two independent observers, who were blinded to the results during their readings. The prevalence of ocular chlamydiosis in the study area was around 50%. In all, 103 persons (206 eyes) were studied. Three smears from each eye were taken for each subject. The kappa statistic was used to estimate the reproducibility of the stains. Interobserver reproducibility was null, and intraobserver reproducibility ranged between 0.35 and 0.79. The sensitivity of the Giemsa stain was a bit higher than that of the Lendrum stain (28% and 22%, respectively), and the specificity was similar (82% and 85%, respectively). Based on these results, the ability of both stains to detect positive cases was judged to be low, as was their reliability. The Lendrum and Giemsa stains are not adequate tests for the diagnosis of ocular chlamydiosis. For this purpose the use of direct immunofluorescence is recommended.

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