Dynamic variables and fluid responsiveness in patients for aortic stenosis surgery

Area of Science:

• Cardiology
• Anesthesiology
• Critical Care Medicine

Background:

• Aortic stenosis is a prevalent valvular disease associated with increased mortality during non-cardiac surgery.
• Hemodynamic management post-aortic stenosis surgery is challenging.
• Fluid responsiveness prediction in aortic stenosis patients undergoing surgery requires further investigation.

Purpose of the Study:

• To evaluate the efficacy of dynamic variables in predicting fluid responsiveness before and after aortic valve replacement.
• To compare the predictive performance of stroke volume variation, pulse pressure variation, and Pleth variability index.

Main Methods:

• An observational study involving 32 patients undergoing aortic valve replacement.
• Fluid responsiveness was assessed using stroke volume increase (≥15%) following a fluid challenge, measured by esophageal Doppler.
• Dynamic variables (stroke volume variation, pulse pressure variation, Pleth variability index) were analyzed before and after surgery.

Main Results:

• Before aortic valve replacement, stroke volume variation (0.77) and pulse pressure variation (0.75) showed moderate predictive value for fluid responsiveness.
• After surgery, predictive values improved significantly: stroke volume variation (0.90) and pulse pressure variation (0.95).
• Pleth variability index demonstrated limited predictive ability both preoperatively (0.51) and postoperatively (0.72).

Conclusions:

• Arterial pressure-based dynamic variables have limited utility in guiding fluid therapy for aortic stenosis patients preoperatively.
• These variables, especially pulse pressure variation, show enhanced predictive capacity for fluid responsiveness after aortic valve replacement.
• Dynamic variable monitoring may be more beneficial in the postoperative phase for guiding fluid management in these patients.