The Trendelenburg Maneuver versus Passive Leg Raising for Predicting Fluid Responsiveness in High-Risk Postoperative Surgical Patients: A Randomized Controlled Parallel-Group Study

Abstract

Abstract Background: Optimizing intravascular volume in high-risk postoperative surgical patients in the intensive care unit (ICU) requires a reliable assessment of fluid responsiveness, yet commonly used methods have important limitations. Passive leg raising (PLR) is well validated but may be impractical or contraindicated in certain clinical scenarios. The Trendelenburg maneuver (TM) produces a similar preload challenge, but its diagnostic performance in high-risk postoperative patients remains uncertain. Materials and Methods: This prospective, randomized, parallel-group study enrolled 60 high-risk postoperative surgical patients with hypoperfusion in the ICU. Participants were randomly allocated to undergo either TM or PLR. Hemodynamic and echocardiographic variables, including velocity–time integral (VTI), stroke volume, cardiac output (CO), and capillary refill time (CRT), were measured at baseline and 1 min after the assigned maneuver. Fluid responsiveness was defined as an increase in SV or VTI >10%. Diagnostic performance was assessed using receiver operating characteristic analysis. Results: Both TM and PLR produced significant increases in VTI, SV, and CO, along with significant reductions in CRT, with no significant differences between groups. The proportion of fluid responders was similar between TM (40%) and PLR (46.7%). Percentage change in VTI reliably predicted fluid responsiveness in both groups, with an area under the curve of 0.944 for TM and 0.996 for PLR ( P = 0.228). A significant inverse correlation was observed between CRT and percentage change in VTI ( r = −0.268, P = 0.038). Conclusions: TM demonstrates diagnostic performance comparable with PLR for predicting fluid responsiveness in high-risk postoperative surgical ICU patients. TM may represent a practical alternative when PLR was contraindicated or infeasible, supporting more individualized hemodynamic management.