RESUMO
Prolonged air travel is associated with an increased incidence of thromboembolic events. The occurrence of stroke was studied in patients with pulmonary embolism after air travel in a review of all flights arriving at Charles de Gaulle Airport in Paris during an 8-year period. Thromboembolic stroke and patent foramen ovale were diagnosed in four patients with pulmonary embolus.
Assuntos
Medicina Aeroespacial , Embolia Paradoxal/etiologia , Comunicação Interatrial/complicações , Embolia Pulmonar/complicações , Acidente Vascular Cerebral/etiologia , Viagem , Idoso , Afasia/etiologia , Infarto Encefálico/etiologia , Evolução Fatal , Feminino , França/epidemiologia , Hemiplegia/etiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico , Recidiva , Estudos Retrospectivos , Tromboembolia/etiologiaRESUMO
BACKGROUND: Air travel is believed to be a risk factor for pulmonary embolism, but the relation between pulmonary embolism and distance flown has not been documented. The aim of this study was to investigate whether the duration of air travel is related to the risk of pulmonary embolism. METHODS: From November 1993 to December 2000, we systematically reviewed all cases of pulmonary embolism requiring medical care on arrival at France's busiest international airport. Data on the geographic origins of all flights and the numbers of passengers were collected in order to evaluate the incidence of pulmonary embolism per 1 million passenger arrivals as a function of the distance traveled. RESULTS: A total of 135.29 million passengers from 145 countries or other areas arrived at Charles de Gaulle Airport during the period of the study, of whom 56 had confirmed pulmonary embolism. The incidence of pulmonary embolism was much higher among passengers traveling more than 5000 km (3000 mi) (1.5 cases per million, as compared with 0.01 case per million among those traveling less than 5000 km). The incidence of pulmonary embolism was 4.8 cases per million for those traveling more than 10,000 km (6000 mi). CONCLUSIONS: A greater distance traveled is a significant contributing risk factor for pulmonary embolism associated with air travel.
Assuntos
Embolia Pulmonar/epidemiologia , Viagem , Medicina Aeroespacial , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/etiologia , Estudos Retrospectivos , Fatores de Risco , Fatores de TempoRESUMO
A composite consisting of a brittle multiphase matrix containing both an Al-based quasicrystalline phase (psi) and an ordered body centred cubic phase (beta) and a relatively ductile ordered body centred cubic intermetallic FeAl phase has been developed as an abrasive wear-resistant coating material. It is applied as a 500 µm thick layer onto stainless steel substrates through plasma spray processing. The microstructure of such materials can be readily examined by optical and scanning electron microscopy, but the inherent difficulty of preparing transmission electron microscope (TEM) samples has inhibited higher resolution studies. However, the relatively recent development of the focused ion beam (FIB) miller as a tool in materials science provides a method ideal for the preparation of TEM specimens of these materials. In this study a coating consisting of a mixture of an Al-Cu-Fe based quasicrystal and FeAl+Cr was deposited on to a 304 stainless steel substrate. TEM specimens were prepared using a FIB and subjected to detailed microstructural characterization. The structure consisted of elongated bands of a FeAl phase about 100 nm in width and several micrometres in length, which enclosed more equiaxed regions about 1 µm in diameter that consisted of fine mixtures of quasicrystal and two Al-Fe-Cu phases isostructurally related to FeAl.