[en] In 11 anaesthetised pigs the accuracy of the three-element (WK3) and the four-element (WK4) Windkessel models to describe hemodynamic properties of the pulmonary circulation was compared during six different experimental conditions increasing pulmonary arterial pressure: increase in left atrial pressure, increase in alveolar pressure, increase in pulmonary blood flow, endotoxin shock, mechanical obstruction of left pulmonary artery or histamine infusion. Our results showed that WK4 fitted better the data than did WK3 because values of 1-R2 decreased from 6 percent (WK3) to 1.4 percent (WK4) when WK4 was used (P < 0.0005). 1-R2 was an adequate marker of the accuracy of the linear regression used to solve equations of both models. Compliance values estimated by WK4 were decreased by 5% comparatively to WK3 (P = 0.008). However, this difference can be considered as not physiologically relevant. Values of characteristic resistance corresponding to R1 + (L/R2C) in WK4 and to R1 in WK3 were not different (P = 0.22). The relative changes in R1, R2, and C observed due to the different experimental conditions were comparable regardless of the model. In conclusion, the conversion of WK3 in WK4 by adding an inductance, whose physiological meaning is not clear, resulted in an increased statistical accuracy of the model, but did not seem to have relevant influence on parameters or their evolution during experimental conditions.
Disciplines :
General & internal medicine
Author, co-author :
Lambermont, Bernard ; Centre Hospitalier Universitaire de Liège - CHU > Frais communs médecine
Gérard, Paul ; Université de Liège - ULiège > Département de mathématique > Statistique (aspects expérimentaux)
Detry, Olivier ; Centre Hospitalier Universitaire de Liège - CHU > Chirurgie abdominale- endocrinienne et de transplantation
Kolh, Philippe ; Université de Liège - ULiège > Département des Sciences biomédicales et précliniques > Service de Biochimie et de Physiologie humaines, normale et pathologique
Potty, P.
Defraigne, Jean-Olivier ; Université de Liège - ULiège > Département des sciences biomédicales et précliniques > Biochimie générale
D'Orio, Vincenzo ; Université de Liège - ULiège > Département des sciences cliniques > Médecine d'urgence - bioch. et phys. hum. normales et path.
Marcelle, Roland ; Université de Liège - ULiège > Relations académiques et scientifiques (Médecine)
Language :
English
Title :
Comparison between Three- and Four-Element Windkessel Models to Characterize Vascular Properties of Pulmonary Circulation
AUDI S, DAWSON C, RICKABY DA, LINEHAN JH (1991): Localization of the sites of pulmonary vasomotion by use of arterial and venous occlusion. J Appl Physiol 70: 2126-2136.
BERGEL DH, MILNOR WH (1965): Pulmonary vascular impedance in the dog. Circ Res 16: 401-415.
BURATTINI R, GNUDI G (1982): Computer identification of models for the arterial tree input impedance: comparison between two new simple models and first experimental results. Med Biol Eng Comp 20: 134-144.
D'ORIO V, HALLEUX J, RODRIGUEZ LM, WAHLEN C, MARCELLE R (1986): Effects of Escherichia coli endotoxin on pulmonary vascular resistance in intact dogs. Crit Care Med 14: 802-806.
DUJARDIN J, STONE DN, FORCINO CD, PAUL LT, PIEPER HP (1982): Effects of blood volume changes on characteristic impedance of the pulmonary artery. Am J Physiol 242: H197-H202.
FANG K, KRAHMER RL, RYPINS EB, LAW WR (1996): Starling resistor effects on pulmonary artery occlusion pressure in endotoxinic shock provide inaccuracies in left ventricular compliance assessments. Crit Care Med 24: 1618-1625.
FITZPATRICK JM, GRANT BJB (1990): Effects of pulmonary vascular obstruction on right ventricular afterload. Am Rev Resp Dis 141: 944-952.
FRANK O (1899): Die Grundform des arterielen Pulses erste Abhandlung: mathematische Analyse. Z Biol 37: 483-526.
GRANT BJB, PARADOWSKI LJ (1987): Characterization of pulmonary arterial input impedance with lumped parameters models. Am J Physiol 252: H585-H593.
GRANT BJB, CANTY JM (1989): Effect of cardiac output on pulmonary hemodynamics. Resp Physiol 76: 303-318.
HOPKINS RA, HAMMON JW, MCHALE PA, SMITH PK, ANDERSON RW (1980): An analysis of the pulsatile hemodynamic responses of the pulmonary circulation to acute and chronic pulmonary venous hypertension in the awake dog. Circ Res 47: 902-910.
KUSSMAUL WG, NOORDERGRAAF A, LASKEY WK (1992): Right ventricular-pulmonary arterial interactions. Ann Biomed Eng 20: 63-80.
LIEBER BB, GRANT BJB (1994): Beat-by-beat changes of viscoelastic and inertial properties of the pulmonary arteries. J Appl Physiol 76: 2348-2355.
LINEHAN JH, DAWSON CA, RICKABY DA (1982): Distribution of vascular resistance and compliance in a dog lung lobe. J Appl Physiol 53: 158-168.
PIENE H (1986): Pulmonary arterial impedance and right ventricular function. Phys Rev 66: 606-652.
PIENE H, HAUGE A (1976): Reduction of pulsatile hydraulic power in the pulmonary circulation caused by moderate vasoconstriction. Cardiovasc Res 10: 503-513.
PIENE H, SUND T (1982): Does normal pulmonary impedance constitute the optimum load for the right ventricle? Am J Physiol 242: H154-H160.
POCHET T, GERARD P, MARNETTE JM, D'ORIO V, MARCELLE R, FATEMI M, FOSSION A, JUCHMES J (1992): Identification of three-element Windkessel model: comparison of time and frequency domain techniques. Arch Int Physiol Bioch 100: 295-301.
POCHET T, GERARD P, LAMBERMONT B, DETRY O, D'ORIO V, DEFRAIGNE JO, FOSSION A, LIMET R (1996): Selection and identification of lumped models of the arterial vasculature using multiple regression and backward elimination in the time domain. Med Biol Eng Comp 34, Suppl. 1, part 1: 107-108.
POULEUR H, LEFEVRE J, VAN EYLL C, JAUMIN PM, CHARLIER AA (1978): Significance of pulmonary input impedance in right ventricular performance. Cardiovasc Res 12: 617-629.
SHIM Y, PASIPOULARIDES A, STRALEY CA, HAMPTON TG, SOTO PF, OWEN CH, DAVIS JW, GLOWER DD (1994): Arterial Windkessel parameter estimation: a new time-domain method. Ann Biomed Eng 22: 66-77.
STERGIOPOULOS N, MEISTER JJ, WESTERHOF N (1995): Evaluation of methods for estimation of total arterial compliance. Am J Physiol 268: H1540-H1548.
WESTERHOF N, BOSMAN F, VRIES CJD, NOORDERGRAAF A (1969): Analog studies of the human systemic arterial tree. J Biomech 2: 121-143.
WESTERHOF N, SIPKEMA P, VAN DEN BOS GC, ELZINGA G (1972): Forward and backward waves in the arterial system. Cardiovasc Res 6: 648-656.
WESTERHOF N, SIPKEMA P, ELZINGA G, MENGO JP (1979): Arterial impedance. In: Hwang NHC, Cross DR, Patels DJ, Eds., Cardiovascular Studies, Clinical and Research Applications of Engineering Principles, Baltimore, pp. 129-130.