Figure 1. Composite left pulmonary vascular pressure-flow (LPQ) plots in seven dogs at baseline and after U46619 preconstriction (P < 0.01) in the conscious state and during isoflurane anesthesia. Composite LPQ plots were generated using the regression parameters from each continuously measured LPQ plot, as described in Materials and Methods. Compared with the conscious state, isoflurane had no net effect on the baseline LPQ relation. The dose of U46619 was titrated to achieve the same degree of preconstriction in the conscious and isoflurane-anesthetized states.