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Objective: Oxygen consumption (VO2) obtained from respiratory gases by indirect calorimetry (VO2,IC) with a metabolic monitor integrated in a ventilator were to be compared to VO2 obtained by the Fick principle (VO2,Fick) in septic patients following an increase in oxygen delivery (DO2) induced by positive inotropic support.Design: Prospective clinical study.Setting: University Hospital, Surgical Intensive Care Unit (ICU).Patients: Thirty patients suffering from sepsis.Interventions: DO2 was increased by dobutamine infusion, starting with an initial dosage of 5 microg x kg x min, increased to a maximum of 10 microg x kg x min.Measurements and Main Results: Dobutamine infusion induced a dosage-related increase in DO2 (from 577 +/- 192 to 752 +/- 202 ml x min x m2, p < 0.01), which was associated with a statistically significant increase in VO2,IC (from 173 +/- 30 to 188 +/- 28 ml x min x m2, p < 0.01) and in VO2,Fick (from 140 +/- 25 to 156 +/- 24 ml x min x m2, p < 0.01). The comparison between VO2,IC and VO2,Fick revealed differences (bias and precision--33 +/- 32 ml x min x m2).Conclusions: With a metabolic monitor integrated in a ventilator it was possible to carry out continuous monitoring of calorimetric data under clinical conditions. In contrast to previous studies using indirect calorimetry, this study showed a moderate correlation between VO2 and DO2 in septic patients using either method. The clinical relevance of this finding requires further investigation. Different factors (e. g. injectant temperature, pulmonary VO2) produced substantial differences between VO2,IC and VO2,Fick as previously shown. [ABSTRACT FROM AUTHOR]

Data acquired prospectively from 134 patients with acute renal failure requiring dialysis in a medical intensive care unit (ICU) were analysed in order to derive indicators predicting ICU-survival. Mortality in the ICU was 56.7%. Linear discriminant analysis correctly predicted outcome in 79.9% at the start of dialysis, and 84.7% at 48 h after the first dialysis. The most important predictive variables were mechanical ventilation and low blood pressure. On the other hand, the total correct classification rates achieved by a standardised system for scoring ICU-patients (APACHE II) did not exceed 58.2%. It is concluded that outcome prediction by APACHE II and even by the discriminant functions is too inaccurate to become the basis for clinical decisions either concerning the initiation or the continuation of dialysis treatment in ARF. [ABSTRACT FROM AUTHOR]