[Predictivity associated with oxygen-transporting hemodynamic parameters: relation between the cardiac index and oxygen extraction].

Abstract

OBJECTIVE: To verify the predictivity of a diagram with the cardiac index (CI) on the y-axis and the oxygen extraction (O2ER) on the x-axis and to verify if the haemodynamic therapy could change the outcome. DESIGN: A retrospective study on a consecutive series of patients. SETTING: University Intensive Care Unit of Ancona. SUBJECTS: 65 critically ill patients, subdivided in survivors (38) and non survivors (27). INTERVENTIONS: All the patients have been monitored with a Swan-Ganz catheter. MEASUREMENTS: CI and O2ER at the admission (T0), at 12 (T1), 24 (T2) and 48 hours (T3) from T0. The diagram CI/02ER has been subdivided in 9 parts on the basis of the normal values of CI (> or = 2,5 and < or = 3,5 1/min/m2) and of O2ER (< or = 24 and > or = 28%). RESULTS: At T2 most of survivors (73.7%) is on the most favourable part of the diagram, with the CI and the O2ER normal or increased, while only 21.4% of non survivors is in this part. On the contrary only 26.3% of survivors versus 78.6% of non survivors are in the less favourable part of the diagram. The chi 2-test shows a good significantly (p = 0.003) in the different distribution on the diagram between survivors and non survivors. A 2 x 2 table has been made. We found: sensibility 78.6% specificity 73.7% and total correct 75.4%. In any other time it has been found a significant different distribution on the diagram between survivors and non survivors. CONCLUSIONS: This diagram can be useful to predict the short term outcome in non septic patients, because at 24 hours give a correct prediction of the outcome in 3 patients on 4, with a good prediction either of the good outcome or of the exitus.