The Clinical Research Of Vasopressors’ Influences On Stroke Volume Variation And Pulse Pressure Variation

Research No.1 Comparisons of the different vasopressors’influences on stroke volume variation and pulse pressure variationObjective Studies have shown that induced hypertension decreases PPV and SVV, this study want to discuss whether the different vasopressors’influences on PPV and SVV are the same or not.Methods 94 patients undergoing elective otologic surgery were randomly divided into three groups:Group P (patients were given phenylephrine), Group D (patients were given dopamine), Group E (patients were given ephedrine). When surgery was ongoing and the circulation state was stable, patients were given the vasopressor to increase the systolic arterial pressure (SAP) to the pre-calculated levels:low level,10% <ΔSAP< 20%; medium level,20%<ΔSAP< 30%; high level,30%<ΔSAP< 40%. When invasive arterial pressure reached the target value, PPV, SVV and other parameters were recorded.Results Dopamine decreased the PPV and SVV more significantly than ephedrine, but less significantly than phenylephrine.Conclusion The influences of phenylephrine, dopamine and ephedrine on SVV and PPV are different due to their different pharmacological mechanisms.Research No.2 Comparison of vasopressor’s influences on stroke volume variation and pulse pressure variation under different volume stateObjective We designed this study to investigate whether vasopressor has the same influence on PPV and SW in hypovolemic and hypervolemic state or not.Methods Twenty patients who would undergo otologic surgery were selected. When operation was performing and the circulation state was stable, the patients were given phenylephrine to increase the systolic arterial pressure (SAP) by 20% to 30% compared with baseline. After the SAP never declined and circulation state was stable, the hydroxyethyl starch 130/0.4 sodium chloride injection was infused as fluid therapy. Phenylephrine was then used to increase the SAP by 20% to 30% compared with the pressure after infusion.Results Phenylephrine could decline the SW and PPV value in hypovolemic and hypervolemic state. In hypovolemic state, ASW and APPV was:5.9±1.1 and 6.6± 2.0; In hypervolemic state, ASW and APPV was:4.0±0.9 and 4.4±0.7.Conclusion Under different volume state, phenylephrine influenced on PPV and SW differently.