Positive-pressure mechanical ventilation supports gas exchange in patients with respiratory failure but is also responsible for significant lung injury. In this study, we have developed an in vitro model in which isolated lung cells can be submitted to a prolonged cyclic pressure-stretching strain resembling that of conventional mechanical ventilation. In this model, cells cultured on a Silastic membrane were elongated up to 7% of their initial diameter, corresponding to a 12% increase in cell surface. The lung macrophage was identified as the main cellular source for critical inflammatory mediators such as tumor necrosis factor-α, the chemokines interleukin (IL)-8 and -6, and matrix metalloproteinase-9 in this model system of mechanical ventilation. These mediators were measured in supernatants from ventilated alveolar macrophages, monocyte-derived macrophages, and promonocytic THP-1 cells. Nuclear factor-κB was found to be activated in ventilated macrophages. Synergistic proinflammatory effects of mechanical stress and molecules such as bacterial endotoxin were observed, suggesting that mechanical ventilation might be particularly deleterious in preinjured or infected lungs. Dexamethasone prevented IL-8 and tumor necrosis factor-α secretion in ventilated macrophages. Mechanical ventilation induced low levels of IL-8 secretion by alveolar type II-like cells. Other lung cell types such as endothelial cells, bronchial cells, and fibroblasts failed to produce IL-8 in response to a prolonged cyclic pressure-stretching load. This model is of particular value for exploring physical stress-induced signaling pathways, as well as for testing the effects of novel ventilatory strategies or adjunctive substances aimed at modulating cell activation induced by mechanical ventilation.

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Percutaneous tracheostomy is associated with a higher prevalence of perioperative complications and, especially, perioperative deaths and cardiorespiratory arrests. Postoperative complication rates are higher with surgical tracheostomy.

Staffing is a key determinant of healthcare-associated infection in critically ill patients. Assuming causality, a substantial proportion of all infections could be avoided if nurse staffing were to be maintained at a higher level.

Based on the data from this study, the prone position can improve oxygenation in severely hypoxemic ARDS patients without deleterious effects on hemodynamics. This beneficial effect does not immediately disappear on return to the supine position. In our patients, an absence of response to this technique was not accompanied by worsening hypoxemia or hemodynamic instability. Repeated daily trials in the prone position should be considered in the management of ARDS patients with severe hypoxemia.

Despite initial improvement in arterial oxygenation with NIPSV in patients with ARF due to severe CAP, the intubation rate is high. However, the more favorable outcome and shorter ICU and hospital stays when intubation is avoided, as well as the short delay required to assess the success or failure of NIPSV warrants a trial of NIPSV in this setting. The nursing workload remains stable during NIPSV and does not result predominantly from respiratory therapy interventions.

Objective To determine what influences doctors' decisions about admission of patients to intensive care.

Both techniques are associated with a low rate of serious or intermediate complications when performed by experienced surgeons. There were more minor perioperative complications with PcT and more minor long term complications with SgT.