Outcome after unilateral lung volume reduction surgery in patients with severe emphysema

Objective: Bilateral lung volume reduction surgery (LVRS) has emerged as a palliative treatment option in patients with severe pulmonary emphysema. However, it is not known if a sustained functional improvement can be obtained using an unilateral approach. Methods: We hypothesized that a palliative effect can also be obtained by unilateral LVRS and prospectively assessed lung function, walking distance, and dyspnea before and 3, 6, 12, 18, 24 and 36 months after unilateral LVRS. Results: Twenty-eight patients were operated by the use of video-assisted thoracoscopic surgery (VATS) with a mean follow-up of 16.5 months (range 3-36 months). Forced expiratory volume in 1 s (FEV1) was significantly improved up to 3 months (1007±432 compared to 1184±499 ml, P≪0.001), residual volume up to 24 months (4154±1126 compared to 3390±914 ml, P≪0.01), dyspnea up to 12 months (modified Borg dyspnea scale 6.6±1.8 compared to 3.9±1.8, P=0.01) and walking distance up to 24 months (343±107 compared to 467±77 m, P≪0.05) after unilateral LVRS compared to preoperative values. Overall, 25 of 28 patients reported a subjective benefit after unilateral LVRS. There was no 30-day mortality. Only two patients required surgery on the contralateral side after 4.5 and 6 months, respectively, both suffering from α-1-antitrypsin deficiency. Conclusions: Unilateral LVRS by the use of VATS results in a sustained beneficial effect, improving walking distance and dyspnea for up to 24 months in patients with severe emphysema. The preservation of the contralateral side for future intervention if required renders unilateral LVRS an attractive concept in this difficult palliative situatio

Ultrafine Particles Cross Cellular Membranes by Nonphagocytic Mechanisms in Lungs and in Cultured Cells

High concentrations of airborne particles have been associated with increased pulmonary and cardiovascular mortality, with indications of a specific toxicologic role for ultrafine particles (UFPs; particles < 0.1 μm). Within hours after the respiratory system is exposed to UFPs, the UFPs may appear in many compartments of the body, including the liver, heart, and nervous system. To date, the mechanisms by which UFPs penetrate boundary membranes and the distribution of UFPs within tissue compartments of their primary and secondary target organs are largely unknown. We combined different experimental approaches to study the distribution of UFPs in lungs and their uptake by cells. In the in vivo experiments, rats inhaled an ultrafine titanium dioxide aerosol of 22 nm count median diameter. The intrapulmonary distribution of particles was analyzed 1 hr or 24 hr after the end of exposure, using energy-filtering transmission electron microscopy for elemental microanalysis of individual particles. In an in vitro study, we exposed pulmonary macrophages and red blood cells to fluorescent polystyrene microspheres (1, 0.2, and 0.078 μm) and assessed particle uptake by confocal laser scanning microscopy. Inhaled ultrafine titanium dioxide particles were found on the luminal side of airways and alveoli, in all major lung tissue compartments and cells, and within capillaries. Particle uptake in vitro into cells did not occur by any of the expected endocytic processes, but rather by diffusion or adhesive interactions. Particles within cells are not membrane bound and hence have direct access to intracellular proteins, organelles, and DNA, which may greatly enhance their toxic potential