Title: Does Central Venous Pressure Predict Fluid Responsiveness?
Abstract: To the Editor: Marik and coauthors1Marik PE Baram M Vahid B Does central venous pressure predict fluid responsiveness?.Chest. 2008; 134: 172-178Abstract Full Text Full Text PDF PubMed Scopus (1170) Google Scholar 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,2Guyton AC Hall JE Textbook of medical physiology. 9th ed. WB Saunders, Philadelphia, PA1996Google Scholar in which right atrial pressure is a key independent variable influencing both systemic venous return and right ventricular output.2Guyton AC Hall JE Textbook of medical physiology. 9th ed. WB Saunders, Philadelphia, PA1996Google Scholar, 3Berne RM Levy MN Cardiovascular physiology. 5th ed. CV Mosby, St Louis, MO1986Google Scholar 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,4Rivers E Nguyen B Havstad S et al.Early goal-directed therapy in the treatment of severe sepsis and septic shock.N Engl J Med. 2001; 345: 1368-1377Crossref PubMed Scopus (8115) Google Scholar and while dynamic parameters may have an increasing role in guiding fluid replacement,5Michard F Teboul J-L Predicting fluid responsiveness in ICU patients.Chest. 2002; 121: 2000-2008Abstract Full Text Full Text PDF PubMed Scopus (1044) Google Scholar it may be premature to discard CVP measurements in ICU patients.