Critical care : the official journal of the Critical Care Forum
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Comparative Study
Effects of descending positive end-expiratory pressure on lung mechanics and aeration in healthy anaesthetized piglets.
Atelectasis and distal airway closure are common clinical entities of general anaesthesia. These two phenomena are expected to reduce the ventilation of dependent lung regions and represent major causes of arterial oxygenation impairment in anaesthetic conditions. In the present study, the behavior of the elastance of the respiratory system (Ers), as well as the lung aeration assessed by CT-scan, was evaluated during a descendent positive end-expiratory pressure (PEEP) titration. This work sought to evaluate the potential usefulness of the Ers monitoring to set the PEEP in order to prevent tidal recruitment and hyperinflation of healthy lungs under general anaesthesia. ⋯ In healthy piglets under a descending PEEP protocol, the PEEP at minimum Ers presented a compromise between maximizing NA areas and minimizing tidal re-aeration and hyperinflation. High levels of PEEP, greater than 8 cmH2O, reduced tidal re-aeration but enlarged hyperinflation with a concomitant decrease in normally aerated areas.
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Comparative Study
Effects of thoraco-pelvic supports during prone position in patients with acute lung injury/acute respiratory distress syndrome: a physiological study.
This study sought to assess whether the use of thoraco-pelvic supports during prone positioning in patients with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) improves, deteriorates or leaves unmodified gas exchange, hemodynamics and respiratory mechanics. ⋯ The application of thoraco-pelvic supports decreases chest wall compliance, increases pleural pressure and slightly deteriorates hemodynamics without any advantage in gas exchange. Consequently, we stopped their use in clinical practice.
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The purpose of this study was to determine if noninvasive transcranial oxygen saturation (StcO2) and Bispectral Index (BIS) correlate with severe traumatic brain injury intensive care unit (ICU) outcomes. ⋯ Numerous significant associations with ICU outcomes indicate that BIS and StcO2 are clinically relevant. The independent associations of BIS, StcO2, and ICP with outcomes suggest that noninvasive multi-modal monitoring may be beneficial. Future studies of patients with BIS > or =60 or StcO2 > or =70 will determine if select patients can be managed without ICP monitoring and whether marginal ICP can be observed. An increased CAP index is associated with poor outcome.
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Comparative Study
Influence of fluid resuscitation on renal microvascular PO2 in a normotensive rat model of endotoxemia.
Septic renal failure is often seen in the intensive care unit but its pathogenesis is only partly understood. This study, performed in a normotensive rat model of endotoxemia, tests the hypotheses that endotoxemia impairs renal microvascular PO2 (microPO2) and oxygen consumption (VO2,ren), that endotoxemia is associated with a diminished kidney function, that fluid resuscitation can restore microPO2, VO2,ren and kidney function, and that colloids are more effective than crystalloids. ⋯ The loss of kidney function during endotoxemia could not be explained by an oxygen deficiency. Renal oxygen redistribution could for the first time be demonstrated during fluid resuscitation. HES130/0.4 had no influence on the VO2,ren and restored renal function with the least increase in the amount of renal work.
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Review Meta Analysis
Kinetic bed therapy to prevent nosocomial pneumonia in mechanically ventilated patients: a systematic review and meta-analysis.
Nosocomial pneumonia is the most important infectious complication in patients admitted to intensive care units. Kinetic bed therapy may reduce the incidence of nosocomial pneumonia in mechanically ventilated patients. The objective of this study was to investigate whether kinetic bed therapy reduces the incidence of nosocomial pneumonia and improves outcomes in critically ill mechanically ventilated patients. ⋯ While kinetic bed therapy has been purported to reduce the incidence of nosocomial pneumonia in mechanically ventilated patients, the overall body of evidence is insufficient to support this conclusion. There appears to be a reduction in the incidence of nosocomial pneumonia, but no effect on mortality, duration of mechanical ventilation, or intensive care or hospital length of stay. Given the lack of consistent benefit and the poor methodological quality of the trials included in this analysis, definitive recommendations regarding the use of this therapy cannot be made at this time.