Mathematical Behavior of MEFV Curves in Childhood Asthma and the Role of Curvature in Quantifying Flow Obstruction
Figure 2
Corresponding plots of second derivative, , versus expired volume, V, for the pediatric patients presented in Figure 1. Coordinates are as shown in the top left corner subplot. Note that all plots illustrate a similar characteristic behavior: (1) an initial monotonically increasing profile where which (2) settles towards a small finite positive steady-state value, with . Several examples illustrate an overshoot before converging towards a steady-state value (e.g. fifth row, second column), while others show a period of oscillation about the x-axis before reaching their steady-state value (e.g. first row, second column). Steady-state values of are indicated in each subplot.
