Marik and coauthors1 argue that the poor correlation between right atrial or central venous pressure (CVP) and indexes of fluid responsiveness after fluid administration limit the value of CVP measurement and conclude that CVP should not be a factor in fluid administration decisions. This appears to be at odds with the classic principles of circulatory physiology by Guyton and Hall,2 in which right atrial pressure is a key independent variable influencing both systemic venous return and right ventricular output.2–3 In these constructs, venous return may be independent of right atrial pressure at low pressures while right ventricular output may be independent of right atrial pressure at high pressures, in agreement with the review, but not in the middle pressure range. In addition, the failure to find correlations between CVP and indexes of fluid responsiveness might be influenced by ongoing fluid losses or gains that were not necessarily easily measurable. Finally, in many clinical situations, the success or failure of fluid resuscitation measures is not determined by preset goals in terms of cardiac output or other indexes of cardiac performance but by criteria such as pressor requirements or blood lactate concentrations. While the current recommendations guiding fluid replacement use CVP as only one of a number of clinical parameters to follow,4 and while dynamic parameters may have an increasing role in guiding fluid replacement,5 it may be premature to discard CVP measurements in ICU patients.