Mathematical Behavior of MEFV Curves in Childhood Asthma and the Role of Curvature in Quantifying Flow Obstruction

  • Spycher B
  • Frey U
  • Wildhaber J
  • et al.
N/ACitations
Citations of this article
6Readers
Mendeley users who have this article in their library.

Abstract

Maximal expiratory flow-volume (MEFV) curves of pediatric patients are investigated using differentiation schemes and by computing their second derivative, d2V˙/dV2 . Results show that spirometric tracings illustrate a characteristic well-defined behavior, where two distinct regions of the MEFV curve may be identified: (1) a concave profile during the initial expiratory maneuver, and (2) a convex profile over the greater lower region of the descending phase of the MEFV curve; this latter region is characterized by an approximately constant positive value of d2V˙/dV2 such that the descending MEFV limb may be captured by a quadratic function. Based on simple expiratory flow modeling, we show that d2V˙/dV2 , and alternatively the local geometrical curvature κ(V) , yield a measure of the relative degree of flow obstruction. In view of future clinical applications, we make use of an “average curvature index”, to assist clinician’s assessment of asthma severity, by quantifying curvature and summarizing global information in MEFV curves.

Cite

CITATION STYLE

APA

Spycher, B., Frey, U., Wildhaber, J. H., & Sznitman, J. (2012). Mathematical Behavior of MEFV Curves in Childhood Asthma and the Role of Curvature in Quantifying Flow Obstruction. ISRN Pulmonology, 2012, 1–13. https://doi.org/10.5402/2012/305176

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free