Fig. 2. Change in the proportion of inert gas shunt (bottom ), low ventilation–perfusion (˙Va/˙Q;middle ), and normal ˙Va/˙Q units (top ) with increasing perfluorocarbon dose during partial liquid ventilation in an acute lung injury (ALI) model. Note that most of the shunt units were converted to low ˙Va/˙Q units at all the doses. A small proportion of shunt units was converted to normal ˙Va/˙Q units at the functional residual capacity dose. Other ˙Va/˙Q units (high ˙Va/˙Q, Vd/Vt) are not shown in the stack bar. * P < 0.05 compared with ALI.