The Additional value of microcirculatory imaging in critically ill patients

Abstract

Hemodynamic monitoring is essential in the care of every critically ill patient. One of the main goals of hemodynamic support is to preserve tissue perfusion. It is however known that tissue perfusion is more related to microcirculatory perfusion than systemic hemodynamic perfusion. Monitoring of the microcirculation has long been difficult. Due to the recent technologic advances it is nowadays possible to easily assess, microcirculatory perfusion at the bedside of critically ill patients. In this order laser speckle imaging (LSI) technique seems a promising tool to study several physiological and pathophysiological microcirculatory processes especially in settings where direct contact with the studied tissue is unwanted (e.g. during (neuro)surgical procedures). However whether LSI could replace currently used techniques needs further exploration. Furthermore microcirculatory imaging in critically ill patients admitted to the intensive care could be used to guide fluid administration and fluid withdrawal. Using a videomicroscopic device, such as the sidestream dark field (SDF)-imager, fluid responsiveness can be monitored during fluid administration. Moreover, hypotension can be predicted when using peripheral perfusion index during fluid withdrawal. These findings demonstrate that additional microcirculatory imaging could be used to early identify specifically those patients in need of additional (fluid) therapy and open the perspective of microcirculation based fluid resuscitation. However, because we studied rather small sample sizes, it is difficult to discuss whether systemic hemodynamic monitoring can be replaced for microcirculatory monitoring. Although, combining both seems to have sufficient additional value.