Pulse densitometer indocyanine green dilution curves: a simple applicable and accurate method for determination of cardiac shunts.

Objective: Adequate hemodynamic evaluation is crucial in the management of patients with congenital heart disease. Although non-invasive diagnostic tools have reduced the need for invasive procedures, cardiac catheterization is still mandatory for absolute quantification of pressures, flows and vascular resistances in selected patients. We therefore investigated the feasibility of a new technique, non-invasive pulse densitometry (PD) in patients with intracardiac shunts and compared its results with the established standards: cuvette densitometry (CD) and oximetry (OX).

Misconceptions in reporting oxygen saturation.

Background: We describe some misconceptions that have become common practice in reporting blood gas and cooximetry results. In 1980, oxygen saturation was incorrectly redefined in a report of a new instrument for analysis of hemoglobin (Hb) derivatives. Oxygen saturation (sO2) was redefined as the ratio of oxyhemoglobin (O2Hb) to total Hb instead of the ratio of O2Hb to active Hb (O2Hb + desoxyhemoglobin).