Intensive care medicine
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Intensive care medicine · Jul 1999
The aetiology and pathogenesis of cardiopulmonary bypass-associated metabolic acidosis using polygeline pump prime.
The pathogenesis of the metabolic acidosis of cardiopulmonary bypass (CPB) is not fully understood. New quantitative methods of acid-base balance now make it possible to describe it more clearly. Accordingly, we studied acid-base changes during CPB with polygeline pump prime and defined and quantified the factors which contribute to metabolic acidosis. ⋯ Using quantitative biophysical methods, it can be demonstrated that, in patients receiving a pump prime rich in chloride and polygeline, the metabolic acidosis of CPB is mostly due to iatrogenic increases in serum chloride concentration and unmeasured strong anions (SIG). Its development is partially attenuated by iatrogenic hypoalbuminaemia. Changes in lactate concentrations did not play a role in the development of metabolic acidosis in our patients.
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Intensive care medicine · Jul 1999
Comparative StudyComparison of different methods for dead space measurements in ventilated newborns using CO2-volume plot.
The aim of the study was to test the applicability of Ventrak 1550/Capnogard 1265 (V-C) for respiratory dead space (VD) measurement and to determine anatomic (VDana), physiologic (VDphys), and alveolar dead spaces (VDalv) in ventilated neonates. ⋯ In ventilated newborns, dead space measurements were possible only in one-third by SBT-CO2, but in all cases by Bohr/Enghoff equations. Improved software could further reduce the time needed for one analysis.
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Intensive care medicine · Jul 1999
Aspiration of dead space allows normocapnic ventilation at low tidal volumes in man.
Aspiration of dead space (ASPIDS) improves carbon dioxide (CO2) elimination by replacing dead space air rich in CO2 with fresh gas during expiration. The hypothesis was that ASPIDS allows normocapnia to be maintained at low tidal volumes (VT). ⋯ The results of this study suggest that ASPIDS may be a useful and safe modality of mechanical ventilation that limits alveolar pressure and minute ventilation requirements while keeping PaCO2 constant.