Stroke volume variation (SVV) and pulse pressure variation (PPV) are dynamic preload indicators. Specific interactions of the cardiovascular system and lungs under mechanical ventilation cause cyclic variations of SVV and PPV. Real time measurement of SVV and PPV by arterial pulse contour analysis is useful to predict volume responsiveness in septic patients. Results of a prospective, 2-year observational study conducted at Department of Anesthesiology, Resuscitation and Intensive Care, Zagreb University Hospital Center, are presented. Volume responders and non-responders were defined. Correlation between SW, PPV, stroke volume index (SVI) and other hemodynamic data in septic patients was analyzed. The study was conducted from September 2009 to December 2011. Sepsis group included 46 patients (22 male, age 46 +/- 6, APACHE II score 26 +/- 5, and 24 female, age 41 +/- 6, APACHE II score 24 +/- 4) undergoing major abdominal surgery with clinically and laboratory confirmed sepsis, defined according to the international criteria.