Does the systolic pressure variation change in the prone position

Objective The Systolic pressure variation (SPV) is known to be a sensitive indicator of hypovolemia. However, the SPV may be elevated due to other reasons, such as changes in lung compliance or tidal volumes. Using the SPV to monitor the hemodynamic status of patients in the prone position may, therefore, be problematic due to possible effects of increased abdominal pressure on both venous return and lung compliance. The purpose of this study is to examine whether or not the SPV changes significantly when placing the patient in the prone position.