Research advances of fluid responsiveness evaluation by non-invasive circulatory monitoring indicators based on "heart-lung interactions"

Hitherto, dynamic hemodynamic indicators based on "heart-lung interactions" are the gold standard for guiding fluid resuscitation, but such indicators often were obtained by invasive monitoring and complexity process. In recent years, with the emergence of non-invasive methods such as continuous non-invasive arterial pressure (CNAP), hemodynamic monitoring system and ultrasound mon-itoring system were used in clinic, new prospects for the application of heart-lung interactions indicators for volume therapy were opened up. This review describes the dynamic hemodynamics indicators based on "heart-lung interactions" measured by CNAP system and ultra-sound monitoring for estimating the volume responsiveness. Application of both methods has certain debate. Non-invasive monitoring for assessing volume responsiveness is the trend of clinical fluid therapy. However, it is not currently recommended to use a non-invasive method to guide fluid therapy because its application conditions are limited. But it can be used as a supplement of invasive monitoring to help doctors perform proper fluid management and reduce adverse events. Key words: Heart-lung interactions; Ultrasound; Continuous non-invasive arterial pressure; Fluid responsiveness