RESUMO
BACKGROUND: With increasing knowledge on the adverse health effects of certain constituents of PM (particulate matter), such as silica, metals, insoluble ions, and black carbon, PM has been under the attention of work safety experts. Previously, we investigated the perceptions of blue-collar workers in highly exposed areas of work. Subsequently, we developed an instruction folder highlighting the most important aspects of PM risk and mitigation, and tested this folder in a digital experiment. The digital experiment yielded positive results with regards to acquired knowledge about PM, but did not on risk perception or safety behavior. METHODS: In this study, we investigate the effects of the folder when combined with a practical assignment involving a PM exposimeter, showing the amount of particulate matter in microgram per cubic meter in real time on its display for various activities. We tested this at six workplaces of four companies in the roadwork and construction branch. RESULTS: The results indicate that the folder itself yields an increased knowledge base in employees about PM, but the effects of the practical assignment are more contentious. Nevertheless, there is an indication that using the assignment may lead to a higher threat appraisal among employees for high exposure activities. CONCLUSION: We recommend implementing our folder in companies with high PM exposure and focusing further research on appropriate methods of implementation.
Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Humanos , Modelos Psicológicos , Material Particulado/análise , Local de TrabalhoRESUMO
BACKGROUND: Particulate matter (PM) exposure is an important health risk, both in daily life and in the workplace. It causes respiratory and cardiovascular diseases and results in 800,000 premature deaths per year worldwide. In earlier research, we assessed workers' information needs regarding workplace PM exposure, the properties and effects of PM, and the rationale behind various means of protection. We also concluded that workers do not always receive appropriate risk communication tools with regards to PM, and that their PM knowledge appears to be fragmented and incomplete. METHODS: We considered several concepts for use as an educational material based on evaluation criteria: ease of use, costs, appropriateness for target audiences and goals, interactivity, implementation issues, novelty, and speed. We decided to develop an educational folder, which can be used to inform employees about the properties, effects and prevention methods concerning PM. Furthermore, we decided on a test setup of a more interactive way of visualisation of exposure to PM by means of exposimeters. For the development of the folder, we based the information needs on our earlier mental models-based research. We adjusted the folder based on the results of ten semi-structured interviews evaluating its usability. RESULTS: The semi-structured interviews yielded commentaries and suggestions for further improvement, which resulted in a number of alterations to the folder. However, in most cases the folder was deemed satisfactory. CONCLUSION: Based on this study, the folder we developed is suitable for a larger-scale experiment and a practical test. Further research is needed to investigate the efficacy of the folder and the application of the exposimeter in a PM risk communication system.
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Material Particulado , Local de Trabalho , HumanosRESUMO
The aged population has been associated with an increased risk of injury in car-crash, creating a critical need for improved assessment of safety systems. Finite element human body models (HBMs) have been proposed, but require representative geometry of the aged population and high mesh quality. A new hybrid Morphing-CAD methodology was applied to a 26-year-old (YO) 5th percentile female model to create average 75YO and subject-specific 86YO HBMs. The method achieved accurate morphing targets while retaining high mesh quality. The three HBMs were integrated into a side sled impact test demonstrating similar kinematic response but differing rib fracture patterns.
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Acidentes de Trânsito , Corpo Humano , Humanos , Feminino , Idoso , Adulto , Modelos Biológicos , Análise de Elementos Finitos , Fenômenos BiomecânicosRESUMO
Whole-body PMHS (Post Mortem Human Surrogate) testing was conducted on the Accelerative Loading Fixture (ALF), which is designed to generate floor and seat loading conditions at the level, rate, location, direction, and extent seen in UBB (Underbody Blast). The overarching goal of this research effort was to examine potential differences in the lower extremity response of females and males under UBB conditions. The ALF consists of an occupant platform that is driven upward by the detonation of an explosive charge. The floor plate undergoes plastic deformation. The occupant platform supports two rigid seats for surrogates. Twenty un-embalmed PMHS were tested, including 50th-percentile males, 75th-percentile females, and 5th-percentile females. Two test series were conducted. Series A had a target floor speed of 8 m/s (2-ms time-to-peak) with a target seat speed of 5 m/s (4-ms time-to-peak). Series B had a target floor speed of 20 m/s (2-ms time-to-peak) with a target seat speed of 4 m/s (7-ms time-to-peak). Major damage occurred to the femur, tibia, fibula, talus, and calcaneus. Lower extremity damage type, incidence, and extent varied between the two sexes. Fifty-percent probability of calcaneus fracture for less than 3-ms time-to-peak is associated with a 781-g peak tibia vertical acceleration for 50th-percentile males, 650-g for 75th-percentile females, and 396-g for 5th-percentile females. Fifty-percent probability of calcaneus fracture, regardless of time-to-peak, is associated with a 368-g peak femur vertical acceleration for 50th-percentile males, 332-g for 75th-percentile females, and 218-g for 5th-percentile females. These results show differences in kinematics and damage outcome between female and male PMHS in UBB conditions. These findings will inform future decisions regarding the requirements for test capabilities that incorporate the female Warfighter. Ultimately, advancements can be made in injury assessment tools such as improved physical surrogates, injury assessment and prediction criteria, modeling and simulation capabilities, test methods, and the optimization of military ground vehicles, personal protective equipment, and injury countermeasures.
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Traumatismos por Explosões , Fraturas Ósseas , Extremidade Inferior/lesões , Aceleração , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Explosões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Caracteres Sexuais , Estresse Mecânico , Adulto JovemRESUMO
Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe.
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An 80-year soil archive, the 42-plot experimental design at the INRA in Versailles (France), is used here to study long-term contamination by 137Cs atmospheric deposition and the fate of this radioisotope when associated with various agricultural practices: fallow land, KCl, NH4(NO3), superphosphate fertilizers, horse manure and lime amendments. The pertinence of a simple box model, where radiocaesium is supposed to move downward by convectional mechanisms, is checked using samples from control plots which had been neither amended, nor cultivated since 1928. This simple model presents the advantage of depending on only two parameters: alpha, a proportional factor allowing the historical atmospheric 137Cs fluxes to be reconstructed locally, and k, an annual loss coefficient from the plow horizon. Another pseudo-unknown is however necessary to run the model: the shape of historical 137Cs deposition, but this function can be easily computed by merging several curves previously established by other surveys. A loss of approximately 1.5% per year from the plow horizon, combined with appropriate fluxes, provides good concordance between simulated and measured values. In the 0-25cm horizon, the residence half time is found to be approximately 18yr (including both migration and radioactive decay). Migration rate constants are also calculated for some plots receiving continuous long-term agricultural treatments. Comparison with the control plots reveals significant influence of amendments on 137Cs mobility in these soils developed from a unique genoform.
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Agricultura , Césio/química , Fertilizantes/análise , Poluentes Radioativos do Solo/química , Solo/análise , Radioisótopos de Césio/química , Modelos Químicos , Fatores de TempoRESUMO
BACKGROUND: Everyday exposure to radiofrequency electromagnetic fields (RF-EMF) emitted from wireless devices such as mobile phones and base stations, radio and television transmitters is ubiquitous. Some people attribute non-specific physical symptoms (NSPS) such as headache and fatigue to exposure to RF-EMF. Most previous laboratory studies or studies that analyzed populations at a group level did not find evidence of an association between RF-EMF exposure and NSPS. OBJECTIVES: We explored the association between exposure to RF-EMF in daily life and the occurrence of NSPS in individual self-declared electrohypersensitive persons using body worn exposimeters and electronic diaries. METHODS: We selected seven individuals who attributed their NSPS to RF-EMF exposure. The level of and variability in personal RF-EMF exposure and NSPS were determined during a three-week period. Data were analyzed using time series analysis in which exposure as measured and recorded in the diary was correlated with NSPS. RESULTS: We found statistically significant correlations between perceived and actual exposure to wireless internet (WiFi - rate of change and number of peaks above threshold) and base stations for mobile telecommunications (GSMâ¯+â¯UMTS downlink, rate of change) and NSPS scores in four of the seven participants. In two persons a higher EMF exposure was associated with higher symptom scores, and in two other persons it was associated with lower scores. Remarkably, we found no significant correlations between NSPS and time-weighted average power density, the most commonly used exposure metric. CONCLUSIONS: RF-EMF exposure was associated either positively or negatively with NSPS in some but not all of the selected self-declared electrohypersensitive persons.
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Doença/etiologia , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental , Adulto , Idoso , Variação Biológica Individual , Telefone Celular , Exposição Ambiental/análise , Feminino , Cefaleia , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Autoavaliação (Psicologia)RESUMO
As an approach to the problem of the nature of the forces responsible for the stacking interactions between the aminoquinoline ring of the antimalarial chloroquine and the monomeric nucleotide bases, we have examined models in which the aromatic nucleus of the drug is linked to the nucleotide bases by a trimethylene chain. The degree of stacking of the models was determined in different conditions of solvent, pH, and temperature by hypochromism measurement in the UV. The results show that forces of the donor-acceptor type, due to the presence of a positive charge on the quinoline ring at neutral pH, do not bring an important contribution to the stacking interaction between the aminoquinoline and the nucleotide bases, while the influence of the solvent water is fundamental.
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Aminoquinolinas/metabolismo , Antimaláricos/metabolismo , Desoxirribonucleotídeos/metabolismo , Aminoquinolinas/síntese química , Antimaláricos/síntese química , Fenômenos Químicos , Físico-Química , Concentração de Íons de Hidrogênio , Solventes , Espectrofotometria Ultravioleta , TemperaturaRESUMO
Stacking interactions between the aminoquinoline ring of the antimalarial chloroquine and the purine bases have been studied by preparing and examining models in which the quinoline is linked to the base by a trimethylene chain. The degree of stacking of the models which reflects the strength of the interaction was quantitatively determined in water at different temperatures by hypochromism measurement in the uv. Adenine and guanine exhibit equal affinity for the quinoline nucleus as reflected by very close hypochromism values observed for the two models at all temperatures studied.
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Cloroquina , DNA , Guanina , Adenina , Sítios de Ligação , Fenômenos Químicos , Química , Cloroquina/análise , Cloroquina/síntese química , Modelos Químicos , Espectrofotometria Ultravioleta , Temperatura , ÁguaRESUMO
OBJECTIVES: This study was undertaken to explore which diseases of the ear, nose, and throat impact daily functioning of patients in an outpatient setting and to observe how specific demographic variables affect health-related quality of life (HRQOL) in these patients. METHODS: This multicenter observational study was conducted anonymously during a 6-week period at outpatient clinics in adults > or = 18 years of age. The Short Form-12 (SF-12) was used to assess HRQOL. Demographic and clinical variables were recorded for each patient. RESULTS: In data from 5806 patients, the SF-12 physical component score was 43.8, and the mental component score was 49.4. SF-12 physical and emotional functioning scores for ENT patients were poorer than established standards (50 +/- 10) for the U.S. population (P < 0.001). CONCLUSIONS: ENT diseases adversely affect the HRQOL in patients visiting their otolaryngologist. Clinical and demographic variables are important considerations in the measurement of HRQOL.
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Nível de Saúde , Otorrinolaringopatias/fisiopatologia , Qualidade de Vida , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Otorrinolaringopatias/epidemiologia , Inquéritos e QuestionáriosRESUMO
The objectives of the study was to generate data useful to engineers improving crash test dummies and to physicians in anticipating low speed lateral impact injuries to the shoulder. Constant impact mass, distance and variable speeds were used to generate impact forces. Twelve unembalmed human cadavers were studied within 48 hours of death. Pre-test and Post-test physical, X-Ray, and Magnetic Resonance examinations were completed. X-Ray best identified bone injury, Magnetic Resonance intratendinous and intramuscular pathology and autopsy joint instability. Low speed (3.5-7.0 m/sec) impacts under these testing conditions frequently produce soft tissue and bone injuries. Sternoclavicular and acromioclavicular joint instabilities were found in 83% of the cadavers. The most frequent bone fractures were in the distal clavicle of 42% and labral or rotator cuff tears in 13% of the cadavers.
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Acidentes de Trânsito , Lesões do Ombro , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Clavícula/lesões , Feminino , Humanos , Instabilidade Articular/diagnóstico , Instabilidade Articular/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiografia , Ombro/diagnóstico por imagem , Ferimentos e Lesões/diagnósticoRESUMO
OBJECTIVE: This article presents a systematic review of published scientific studies on the potential ecological effects of radiofrequency electromagnetic fields (RF-EMF) in the range of 10 MHz to 3.6 GHz (from amplitude modulation, AM, to lower band microwave, MW, EMF). METHODS: Publications in English were searched in ISI Web of Knowledge and Scholar Google with no restriction on publication date. Five species groups were identified: birds, insects, other vertebrates, other organisms, and plants. Not only clear ecological articles, such as field studies, were taken into consideration, but also biological articles on laboratory studies investigating the effects of RF-EMF with biological endpoints such as fertility, reproduction, behaviour and development, which have a clear ecological significance, were also included. RESULTS: Information was collected from 113 studies from original peer-reviewed publications or from relevant existing reviews. A limited amount of ecological field studies was identified. The majority of the studies were conducted in a laboratory setting on birds (embryos or eggs), small rodents and plants. In 65% of the studies, ecological effects of RF-EMF (50% of the animal studies and about 75% of the plant studies) were found both at high as well as at low dosages. No clear dose-effect relationship could be discerned. Studies finding an effect applied higher durations of exposure and focused more on the GSM frequency ranges. CONCLUSIONS: In about two third of the reviewed studies ecological effects of RF-EMF was reported at high as well as at low dosages. The very low dosages are compatible with real field situations, and could be found under environmental conditions. However, a lack of standardisation and a limited number of observations limit the possibility of generalising results from an organism to an ecosystem level. We propose in future studies to conduct more repetitions of observations and explicitly use the available standards for reporting RF-EMF relevant physical parameters in both laboratory and field studies.
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Campos Eletromagnéticos , Ondas de Rádio , Animais , EcologiaRESUMO
The effects of mineral-supplement delivery system on patterns of supplement use by grazing beef cows were measured in 2 studies. Study 1 was conducted on 4 pastures grazed by pregnant, mature beef cows (BW = 562 ± 38 kg) from February to May. Study 2 was conducted on 4 pastures grazed by lactating beef cows (BW = 579 ± 54 kg) and their calves from May to September. Treatments were mineral delivered in salt-based, granular form (salty) or mineral provided in a low-protein, cooked, molasses-based block (sweet); both were fed ad libitum. The salty supplement was supplied to cattle via a covered mineral feeder; the sweet supplement was supplied via an open-topped barrel. Both salty and sweet supplements were deployed in each pasture. No additional salt was supplied to cattle. Forage use in the vicinity of each supplement-deployment site and the frequency and duration of herd visits to each supplement-deployment site were measured during four 14-d periods during study 1 and seven 14-d periods during study 2. Supplements were moved to new locations within pastures at the beginning of each period. Consumption of the sweet supplement was greater than salty during each data-collection period in study 1; however, relative differences in consumption diminished over time (treatment × time, P = 0.03). In study 2, sweet consumption was greater than salty in periods 1, 6, and 7 but was not different from salty during periods 2, 3, 4, and 5 (treatment × time, P < 0.01). Increased consumption of the sweet supplement in study 1 translated to greater frequency of herd visits to supplement-deployment sites compared with the salty sites (2.82 vs. 2.47 herd visits/d; P = 0.02) and longer herd visits to supplement-deployment sites compared with the salty sites (125.7 vs. 54.9 min/herd visit; P < 0.01). The frequency of herd visits to mineral feeding sites in study 2 was similar (P > 0.10) between treatments for periods 1 through 6; however, herds visited the sweet sites more often than salty during period 7 (P < 0.01). Herd visits to the sweet sites were longer than those to the salty sites in study 2 (83.8 vs. 51.4 min/herd visit; P < 0.01). Forage disappearance within 100 m of supplement-deployment sites was not influenced (P ≥ 0.54) by treatment in either study. Results were interpreted to suggest that the sweet supplement influenced the location of grazing cattle more strongly than the salty supplement and may be more effective for luring cattle into specific areas of pasture during the winter, spring, and early fall but not during summer.
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Criação de Animais Domésticos/métodos , Comportamento Animal/fisiologia , Bovinos/psicologia , Suplementos Nutricionais , Animais , Animais Lactentes , Bovinos/fisiologia , Feminino , Lactação , Distribuição Aleatória , PaladarRESUMO
Extensive research, intervention equipment, money, and media coverage have been directed at controlling Escherichia coli O157:H7 in beef cattle. However, much of the focus has been on controlling this pathogen postcolonization. This study was conducted to examine the performance, health, and shedding characteristics of beef calves that were vaccinated with an E. coli O157:H7 SRP bacterial extract. These calves had been born to cows vaccinated prepartum with the same vaccine. Cows and calves were assigned randomly to one of four treatments: (i) neither cows nor calves vaccinated with E. coli O157:H7 SRP (CON), (ii) cows vaccinated with E. coli O157:H7 SRP prepartum but calves not vaccinated (COWVAC), (iii) calves vaccinated with E. coli O157:H7 SRP but born to cows not vaccinated (CALFVAC), (iv) cows vaccinated with E. coli O157:H7 SRP prepartum and calves also vaccinated (BOTH). Calves born to vaccinated cows had significantly higher titers of anti-E. coli O157:H7 SRP antibodies (SRPAb) in circulation at branding time (P < 0.001). Upon entry to the feedlot, overall fecal E. coli O157:H7 prevalence was 23 % among calves, with 25 % in the CON treatment group, 19 % in the CALFVAC group, 32 % in the COWVAC group, and 15 % in the BOTH group (P > 0.05). Fecal shedding of E. coli O157 on arrival to the feedlot was not correlated with fecal shedding at slaughter (Spearman's rho = -0.02; P = 0.91). No significant effects of cow or calf E. coli O157:H7 SRP vaccination treatment were found on feedlot calf health or performance (P > 0.05), prevalence of lung lesions or liver abscess (P > 0.05), or morbidity, retreatment, or mortality numbers (P > 0.05). The findings of this study indicate that the timing of vaccination of calves against E. coli O157:H7 may be an important consideration for maximizing the field efficacy of this vaccine.
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Doenças dos Bovinos/prevenção & controle , Infecções por Escherichia coli/veterinária , Escherichia coli O157/imunologia , Escherichia coli O157/isolamento & purificação , Vacinas contra Escherichia coli/administração & dosagem , Fezes/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/transmissão , Qualidade de Produtos para o Consumidor , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/transmissão , Proteínas de Escherichia coli/imunologia , Feminino , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Carne/microbiologia , Gravidez , Cuidado Pré-NatalAssuntos
Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/instrumentação , Doença das Coronárias/terapia , Embolização Terapêutica/efeitos adversos , Migração de Corpo Estranho/epidemiologia , Migração de Corpo Estranho/terapia , Stents/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão/métodos , Estudos de Casos e Controles , Estudos de Coortes , Doença das Coronárias/diagnóstico , Doença das Coronárias/mortalidade , Remoção de Dispositivo , Embolização Terapêutica/instrumentação , Feminino , Seguimentos , Migração de Corpo Estranho/diagnóstico , Migração de Corpo Estranho/etiologia , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Probabilidade , Sistema de Registros , Medição de Risco , Taxa de SobrevidaRESUMO
HISTORY AND CLINICAL FINDINGS: A 58-year-old man, previously resident in Russia, was known since the age of 18 years to have arterial hypertension of unknown cause in only the right arm. A single syncope was the only previous symptom. On examination the pressure was 230/110 mmHg in the right arm, 150/100 mmHg in the left one. The pulse in the right arm and neck was strong and heaving, that in the left arm and the legs much more weakly palpable. INVESTIGATIONS: Electrocardiogram and echocardiogram showed left ventricular hypertrophy. The chest radiogram demonstrated rib notching. Digital subtraction angiography revealed aortic arch atresia just distal to the common carotid artery. No other cardiovascular abnormalities were found. TREATMENT: The patient declined operative treatment. Cautious antihypertensive drug treatment with Atenolol (25 mg daily) reduced the pressure in the right arm to 180/90 mmHg. CONCLUSION: This rare malformation of aortic arch atresia should be considered in the differential diagnosis of asymmetrical arterial hypertension in an adult.
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Aorta Torácica/anormalidades , Hipertensão/etiologia , Antagonistas Adrenérgicos beta/administração & dosagem , Angiografia Digital , Anti-Hipertensivos/administração & dosagem , Aorta Torácica/diagnóstico por imagem , Atenolol/administração & dosagem , Diagnóstico Diferencial , Eletrocardiografia , Alemanha , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Federação Russa/etnologiaRESUMO
A new model for experimental research in pigs is reported. It allows comparative analyses in blood, bile and urine in the unanaesthetized pig. Preliminary results to the physiology of biliary excretion and multicompartmental analysis of conjugated bile acids emphasize the applicability of the experimental model. On the basis of these results it is pointed out, that it is possible to analize the distribution and excretion kinetics of conjugated bile acids, namely C14-glycocholic acid, by a 3-compartmental analysis.
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Sistema Biliar/fisiologia , Ácidos Cólicos/metabolismo , Ácido Glicocólico/metabolismo , Modelos Biológicos , Suínos/fisiologia , Administração Oral , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Bile/metabolismo , Bilirrubina/sangue , Cateterismo , Colecistectomia , Veias Jugulares , Cinética , Cateterismo UrinárioRESUMO
Out of a total of 1640 consecutive left heart catheterizations, 70 (58 males and 12 females; mean age 56 +/- 8 years) were performed via the right brachial artery, in most instances because of occlusive disease of the arteries in the pelvic region. 5F catheters were then successfully used for both the coronary and left-ventricular angiographies. Noninvasive examinations after two days (Doppler ultrasound, oscillography at rest and on exercise, acral plethysmography and colour-coded duplex sonography) revealed small haematomas in the region of the arterial puncture in four and a haemodynamically insignificant fistula between brachial artery and vein in one patient but no aneurysm, stenosis or thrombosis at the puncture site. This procedure is thus a valuable addition to invasive cardiological diagnosis.