This video shows a dynamic computed tomography scan (grey scale) of the chest taken for approximately 60 seconds at the hilus in one representative animal during inhibitor price assisted ventilation with BIPAP+SBmean. Acute lung injury was induced by surfactant depletion. See Additional file 3 for comparison with pressure support ventilation (PSV).Click here for file(13M, WMV)Additional file 3:Dynamic computed tomography in a representative animal during pressure support ventilation (PSV). This video shows a dynamic computed tomography scan (grey scale) of the chest taken for approximately 60 seconds at the hilus in a representative animal during assisted ventilation with PSV. Acute lung injury was induced by surfactant depletion. See Additional file 2 for comparison with biphasic positive airway pressure + spontaneous breathing (BIPAP+SBmean).

Click here for file(13M, WMV)AcknowledgementsThis work was supported, in part, by a research grant of the European Society of Anaesthesiology (ESA), Brussels, Belgium. We are indebted to the students of the Pulmonary Engineering Group of the Department of Anesthesiology and Intensive Care Therapy, University Hospital Carl Gustav Carus, Technical University of Dresden, Germany, for their support during the experiments.
In healthy individuals there is a continuous cycle of lactate production and metabolism, which ensures that blood lactate concentrations are normally low [1,2]. Higher blood lactate concentrations occur when lactate production exceeds clearance, when clearance capacity is decreased or more frequently when both occur simultaneously [3,4].

Elevated blood lactate concentrations above the accepted normal reference range (absolute hyperlactataemia) are common and associated with increased hospital mortality in the critically ill [5-12]. Their usefulness in identifying critically ill patients at higher risk of death has led to the adoption of lactate measurement in most blood gas analyzers Anacetrapib and the frequent measurement of lactate in the critically ill.While the normal lactate concentration in unstressed individuals is 1.0 �� 0.5 mmol.L-1 [1,2], patients with critical illness are considered to have normal lactate levels at concentrations of less than 2 mmol.L-1 [13]. Furthermore, this 2 mmol.L-1 cut off may be considered to be a conservative threshold as some have suggested that a level of up to 4 mmol.L-1 is within the normal limits [14].However, it is unknown whether a higher blood lactate concentration within the current reference range (relative hyperlactataemia) might also be associated with increased hospital mortality. This knowledge would be clinically important because the currently used upper reference limit for lactatemia may fail to identify many patients who are at higher risk of death.