Thermodilution transpulmonaire : vers une approche intégrée du cœur et des poumons

Abstract

Most of hemodynamically unstable or severely hypoxemic patients are instrumented with a central venous line and an arterial line. In this context, cardio-respiratory monitoring by transpulmonary thermodilution simply requires the use of a specific thermodilution arterial catheter. In patients with shock, the transpulmonary thermodilution technique allows the simultaneous and rapid assessment of cardiac output, cardiac preload (global end-diastolic volume), cardiac contractility/function (global ejection fraction) and the prediction of fluid responsiveness (pulse pressure and stroke volume variations). In contrast to echocardiography, transpulmonary thermodilution is a non-operator dependent technique that can be used by all care givers, in all ICUs, as often as necessary. In hypoxemic patients, transpulmonary thermodilution allows the identification of patients with pulmonary edema (elevated extravascular lung water) who might benefit from fluid restriction/depletion, assessment of pulmonary vascular permeability, a better understanding of the pathophysiological mechanisms of hypoxemia (pulmonary edema, low cardiac output, right-to-left intracardiac shunt) and the prediction of the possible deleterious hemodynamic effects of PEEP. In summary, the transpulmonary thermodilution technique provides the care giver a simple, reproducible and integrated approach of the heart and the lungs that cannot be considered separately in most of clinical situations.