Objective: So far, only left ventricular functional preload indices are used as a routine to assess volume responsiveness. Right ventricular (RV) functional preload indices have been described, but offer no continuous monitoring. Design and Measurements: Following ethical approval, a pressure-induced right ventricular failure (RVF) was induced with continuous infusion of a thromboxane-A2-analogue (U46619) in 15 anesthetized and ventilated pigs. Before and after increasing mean pulmonary artery pressure (MPAP) by 50%, right ventricular stroke volume variation (RVSVV) was assessed with an ultrasonic pulmonary artery flow probe. Measurements were repeated following volume depletion (- 300 ml) and stepwise re-transfusion (200 ml of whole blood and 200 ml of a colloid solution). Main Results: A significant and systematic increase in RVSVV during induction of RVF was observed. Volume depletion lead to an increase in RVSVV and re-transfusion lead to a decrease in RVSVV. RVSVV was higher and a significant decrease in RVSVV was present in all animals experiencing an increase in CO by more than 5 % during re-transfusion. Conclusion: RVSVV seems to reflect volume requirement of the right ventricle and it might prove a reliable parameter to assess volume responsiveness in RVF.
