Intensive care medicine
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Intensive care medicine · Jan 1998
Multicenter StudyEvaluation of the uniformity of fit of general outcome prediction models.
To compare the performance of the New Simplified Acute Physiology Score (SAPS II) and the New Admission Mortality Probability Model (MPM II0) within relevant subgroups using formal statistical assessment (uniformity of fit). ⋯ Concerning the performance of the models, very large differences were apparent in relevant subgroups, varying from excellent to almost random predictive accuracy. These differences can explain some of the difficulties of the models to accurately predict mortality when applied to different populations with distinct patient baseline characteristics. This study stresses the importance of evaluating multiple diverse populations (to generate the design set) and of methods to improve the validation set before extrapolations can be made from the validation setting to new independent populations. It also underlines the necessity of a better definition of the patient baseline characteristics in the samples under analysis and the formal statistical evaluation of the application of the models to specific subgroups.
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Intensive care medicine · Jan 1998
Increased microvascular water permeability in patients with septic shock, assessed with venous congestion plethysmography (VCP).
To investigate microvascular water permeability (filtration capacity, Kf) in patients with septic and non-septic shock using a new non-invasive method for studying microvascular parameters in man. ⋯ An increase in permeability of microvessels will cause a loss of intravascular fluid and may therefore partially explain the large fluid requirements of patients in shock. It will also favour the development of oedema, which is often found in septic patients. We propose that changes in Kf are useful indices of microvascular malfunction and that VCP allows the non-invasive assessment of these parameters.