[Validity of the V/Q index in the monitoring of critical patients].

: The Authors have controlled the validity of VQI to quantify pulmonary shunt (Qs/Qt). The survey involved (group A) patients who had undergone major surgery and (group B) patients hospitalized in ICU for cardiorespiratory failure. Four subgroups were identified in both the groups according to different values of SaO2. A good correlation, already described by Rasanen, was comproved in the groups and subgroups. However a progressive reduction of the coefficient of correlation from the lower to the higher values of SaO2 was noted. Finally the differences observed between group A and group B, are supposed to be dependent on a greater variability of haemoglobin, in the surgical group, in relation to the time of evaluation.