心脏前负荷测量进展

心脏前负荷在临床应用有重要的指导价值，但监测方法各有利弊，单一温度稀释法PicCCo技术具有广阔的应用前景，较Swan-Ganz导管技术更敏感，可较准确监测心脏前负荷的变化，为指导临床诊断和治疗提供可靠的依据。因临床上受多种因素所影响，PiCCO所测得的胸腔内血容积等参数作为反映心脏前负荷的指标，仍需进行更深入的分析与探讨。目前在临床上还不能忽视传统技术的应用。

Measurement of cardiac preload

Cardiac preload is a very good index in reflecting cardiac function. End-diastolic volume indices determined by transpulmonary thermodilution（TDCOtp） and pulmonary artery thermodilution may give a better estimate of left ventficular preload than pulmonary capillary wedge pressure monitofing（PCWP） and central venous press（CVP）. The PiCCO system （Pulse Contour Cardiac Output system; Pulsion Medical Systems, Munich, Germany） a newly available system, uses integrated transpulmonary thermodilution to measure the volumetric preload parameter global end-diastolic volume index （GEDVI） and includes the total volumes of cardiac atria and ventricles as well as part of the systemic vascular blood volume. Compared with conventional pressure-derived preload assessment, volumetric preload determination by the PiCCO system has been shown to better reflect left ventricular filling. The PiCCO system provides intermittent cardiac output（CO） assessment by TDCOtp, continuous CO measurement by pulse contour analysis （PCCO）, and an estimation of intrathoracic blood volume （ITBV） from GEDV only by transpulmonary single indicator dilution, which should be a valuable parameter of cardiac pretoad.