1. Introduction

Technology progress has given us the opportunity to monitor almost every aspect of the cardiovascular system down to the level of tissue microcirculation. However, the choice of the right tool is often a challenge, depending both on institutional capabilities (availability of the device) and on operator training. The present chapter consists a short literature review about the subject.

It is more than three centuries that Reverend Stephen Hales have made the first invasive measurement of blood pressure and cardiac output [1]. During that time, there has been a tremendous progress both in hemodynamics physiology and pathophysiology understanding and in modes of cardiovascular monitoring. Today, it is considered basic and essential knowledge for every physician. The paradox: the more we know about cardiovascular circulation, the more we understand our ignorance. The present chapter focuses on some of the problems encountered during hemodynamic monitoring.
