PHYSIOLOGICAL MODELLING AND ANALYSIS OF THE PULMONARY MICROCIRCULATION IN SEPTIC PATIENTS

摘要

A physiological model integrating a pulsatile cardiovascular system model with a model of the pulmonary capillary fluid exchange based on the Starling's equations is proposed in order to analyse the micro-circulatory physiological alterations which occur during the evolution of sepsis. Sepsis-induced acute lung injury is typically characterized by an increased microvascular permeability and interstitial edema. Pulmonary edema occurs because the capillary filtration capacity increases and the reflection coefficient to proteins decreases causing fluid leak across the capillary barrier. Patients with severe sepsis may develop respiratory failure and hence requiring ventilatory support. These signs represent the clinical expression of the acute respiratory distress syndrome (ARDS) and are associated with high mortality in medical intensive care units (ICU). The proposed model is used to simulate the cardiovascular hemodynamics under these complex pathophysiological conditions.