A continuous monitoring technique for management of acute pulmonary failure.

Continuous monitoring of mixed venous oxygen saturation (SvO2) and arterial oxygen saturation (SaO2) was used to guide cardiovascular and pulmonary physiologic manipulations in three patients. An index, termed the "shunt index" (SI), of venoarterial admixture (Qva/Qt) was calculated at the bedside. SI correlated significantly in each patient with Qva/Qt (p less than .01). In one of the patients, continuous end-tidal CO2(ETCO2) was also monitored, allowing rapid titrations of ventilator settings and cardiovascular support free from the need to sample arterial and mixed venous blood to assess the effect of each intervention.