THE HEMODYNAMIC CORRELATIONS OF THE CARDIOPULMONARY FLOW INDEX, A RELATIVELY NON INVASIVE TECHNIQUE FOR DIAGNOSIS OF MYOCARDIAL PUMP INSUFFICIENCY

The cardiopulmonary flow index (CPFI) is the ratio of cardiopulmonary blood volume to stroke volume. Objective. To compare the CPFI derived from a first-pass radiocardiogram and electrocardiogram with the usual haemodynamic measurements obtained by bedside catheterisation. Design . Sixty-one patients in a coronary care unit who had flow-directed pul monary artery catheterisation for clinical indications had a CPFI reco rded together with the usual haemodynamic measurements and calculation s. Results. In patients with myocardial pump failure without significa nt pulmonary disease, linear regression analysis indicated that the be st fit for the CPFI could be obtained with a model that used the inver se of stroke index and pulmonary capillary wedge pressure as independe nt variables. Ninety-six per cent of the variation in CPFI can be expl ained by variations in pulmonary capillary wedge pressure and stroke i ndex. The CPFI correlated less well with these variables in patients w ith concomitant lung disease. Conclusion. The CPFI is a potentially us eful and relatively non-invasive index of haemodynamic function in acu tely ill patients without significant pulmonary disease.